ISES 2009 Abstract Book

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Table of Contents Arranged by Session Number with Title

Note: Sessions are numbered as follows:

• First letter indicates day (M=Monday, T=Tuesday, W=Wednesday, R=Thursday) • Text after hyphen indicates session type (SY=symposium, PL=platform,

P=poster, IP=interactive poster) • First digit of the three digit number indicates order of parallel session groupings

(100s=first parallel sessions of the day, 200s=second parallel sessions, 300s=third parallel sessions)

• Last digits of the three digit number are unique numbers For example, M-SY101 is a symposium and is offered during the first set of parallel sessions on Monday. Monday, November 2, 2009 M-SY101: Environmental Influences on Epigenetic Processes and Complex Disease ..... 5 M-SY102: Exposure Assessment Studies in East Asia Countries...................................... 9 M-SY103: Methods and Strategies for the Assessment of Consumer Exposure: Discussion on Approaches to Improve Modeling of the Variability of Consumer Behavior........................................................................................................................................... 13 M-SY104: Enhancing Exposure Assessment for Air Pollution Health Studies: EPA/NERL Cooperative Agreement Program ................................................................. 17 M-SY201: Environmental Influences on Epigenetic Processes and Complex Diseases II........................................................................................................................................... 22 M-SY202: Cookstove Intervention and Indoor Air Pollution Studies in the Developing World – Exposure Assessment and Health Impact - Session A ....................................... 26 M-PL201: Climate, Exposure, and Health........................................................................ 31 M-PL202: Exposure Modeling ......................................................................................... 34 M-P001a: Monday: Exposure, Risk, Epidemiology - Theme: Environmental Epidemiology, Tracking, and Linkages ............................................................................ 37 M-P001b: Monday: Exposure, Risk, Epidemiology - Theme: Air Exposures ................. 47 M-P001c: Monday: Exposure, Risk, Epidemiology - Theme: Developing Exposure Science .............................................................................................................................. 52 M-P001d: Monday: Exposure, Risk, Epidemiology - Theme: Risk Analysis.................. 56 M-P001e: Monday: Exposure, Risk, Epidemiology - Theme: Biomonitoring-Exposure 64 M-P001f: Monday: Exposure, Risk, Epidemiology - Theme: Biomonitoring-Emerging Research & Methods......................................................................................................... 68 M-SY301: Exposure Modeling for Mobile Populations................................................... 73 M-SY302: Cookstove Intervention and Indoor Air Pollution Studies in the Developing World – Exposure Assessment and Health Impact - Session B........................................ 76 M-SY303: From Source to Biomarkers: Linking PBPK with Multimedia Fate and Exposure Models .............................................................................................................. 80 M-PL301: Exposure Assessment in Minnesota................................................................ 85 M-PL302: Exposure and Vulnerable Groups ................................................................... 89

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Tuesday, November 3, 2009 T-SY101: Old vs. New Persistent Organic Pollutants (POPs) - Some Exposure Surprises........................................................................................................................................... 95 T-SY102: Semivolatile Contaminants Indoors: Advances in Environmental Chemistry and Human Exposure Assessment .................................................................................... 99 T-SY103: Exposures in Aircraft Cabins – ACER-RITE FAA Center of Excellence..... 102 T-PL101: Exposure Determinants for Environmental Health Studies ........................... 106 T-IP101: Dietary Exposure ............................................................................................. 111 Wednesday, November 4, 2009 W-SY101: Residential Exposures to Endocrine Disrupting Compounds from Consumer Products and Building Materials: Recent Findings and Future Directions..................... 118 W-PL101: Global Exposure Management...................................................................... 123 W-SY102: Use of Molecular Tools for Source Identification and Risk Assessment in Water Contaminated by Feces ........................................................................................ 127 W-PL102: Engineered Nanomaterials ............................................................................ 131 W-PL201: Biological Exposures .................................................................................... 134 W-SY201: Integrative Exposure Biology and Computational Toxicology for Risk Assessment - Session A .................................................................................................. 138 W-PL202: Microbial Occurrence in the Environment.................................................... 142 W-PL203: Relating Indoor-Outdoor Air ........................................................................ 145 W-PL301: Occupational Exposure Assessment ............................................................. 150 W-SY301: Integrative Exposure Biology and Computational Toxicology for Risk Assessment - Session B .................................................................................................. 154 W-SY302: The Validity and Reliability of Urinary Metabolites as Exposure Biomarkers......................................................................................................................................... 158 W-PL302: Local and Regional Exposure Issues ............................................................ 162 W-IP301: Indoor Air....................................................................................................... 166 W-P001a: Wednesday: Occupational, Water, Pesticides - Theme: Characterizing the Exposure Pathway........................................................................................................... 172 W-P001b: Wednesday: Occupational, Water, Pesticides - Theme: Case Studies .......... 186 W-P001c: Wednesday: Occupational, Water, Pesticides - Theme: Strategies for Exposure Assessments .................................................................................................................... 202 Thursday, November 5, 2009 R-P001a: Thursday: Air - Theme: Methods ................................................................... 208 R-P001b:Thursday: Air - Theme: Exposure Modeling .................................................. 211 R-P001c: Thursday: Air - Theme: Exposure Issues ....................................................... 215 R-P001d:Thursday: Air - Theme: Personal Exposure .................................................... 221 R-P001e: Thursday: Air - Theme: Indoor Exposures ..................................................... 225 R-P001f: Thursday: Air - Theme: Indoor/Outdoor Exposures ....................................... 229 R-P001g: Thursday: Air - Theme: Remote Sensing ....................................................... 232 R-P001h: Thursday: Air - Theme: Outdoor Exposures .................................................. 234 R-SY101: Biomonitoring and CDC Environmental Public Health Tracking................. 245 R-SY102: Community Engagement to Facilitate Exposure Assessment and Environmental Health Research ..................................................................................... 249 R-SY103: Emerging Methods for Comprehensive Measurement of Personal Exposures: Discussion of Emerging Issues in Applying Measures for Exposure, Diet, Physical

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Activity, Stress and Biological Response in the NIH Genes, Environment, and Health Initiative .......................................................................................................................... 253 R-SY104: Biomarkers and Other Measures of Exposure as Tools to Evaluate Exposure of Humans to Pathogens...................................................................................................... 258 R-IP101: Exposure Science for Prioritizing and Evaluating Chemicals ........................ 261 R-SY201: Approaches to Interpreting Biomonitoring Data from Population-level Studies......................................................................................................................................... 267 R-PL201: Time-Activity Patterns ................................................................................... 271 R-SY202: Demonstrations of Emerging Methods for Comprehensive Measurement of Personal Exposures Including Diet, Physical Activity, Stress and Biological Response in the NIH Genes, Environment, and Health Initiative....................................................... 275 R-PL202: Phthalates and Flame Retardants ................................................................... 279 R-IP201: Measuring, Modeling, and Managing Urban Air Contaminants..................... 283

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Monday, November 02, 2009

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Symposium

M-SY101: Environmental Influences on Epigenetic Processes and Complex Disease

A concerted effort has been made by the research community to merge toxicology research with studies of epigenetic mechanisms resulting in the materialization of exposure biology studies that focus on environmental toxins impact on known epigenetic mechanisms or marks, primarily DNA methylation and histone modifications to influence the pathogenesis of complex human diseases. Some aspects of exposure influenced epigenetic aberrant processes NIEHS supported scientists are studying include: • defining the role of CpG island methylation of tumor suppressor genes in the development of human adenocarcinoma of the lung and the influence of environmental exposures on which genes are targeted; • asking whether in utero exposure to an environmentally relevant dose of arsenite accelerates puberty onset and alters mammary gland development; • testing a hypothesis that perinatal exposure to persistent organic polybrominated diphenyl ethers (PBDE) may result in epigenetic changes in developing neurons that impact the development of social and cognitive behavior; • using unbiased epigenetic profiling coupled to high-resolution confirmatory approaches to address the hypothesis that environmental arsenicals act as epimutagens – toxicants that form aberrant epigenetic states that are maintained and heritable even in the absence of the initiating toxicant. • testing the hypothesis that exogenous agents decrease S-adenosylmethionine (SAM) synthesis and dinucleotide methyltransferase1 (Dnmt1) levels or activity would be additive or synergistic in increasing expression of methylation sensitive T cell genes and contribute to the development of autoimmunity; • testing the hypothesis that developing germ cells, which undergo genome-wide epigenetic reprogramming, are especially vulnerable to the epigenetic effects of endocrine disruptors; • the impact of low-dose exposures to ubiquitous environmental estrogens and effect on the prostate epigenome during development and, as well as, promotion of prostate disease with aging; and • exploring whether transplacental exposure to PAHs in humans induces epigenetic reprogramming involving aberrant DNA methylation of specific genes that might be mechanistically related to childhood asthma or airway inflammation; The session also will provide a brief update on the NIH Roadmap Epigenome Program that will inform of opportunities for utilization of Roadmap generated resources. Confirmed presenters for this proposed session are: Steven Belinsky (Lovelace Respiratory Research Institute), Max Costa (New York University), Shuk-Mei Ho (University of Cincinnati), Mary Beth Martin (Georgetown University), Randy Jirtle (Duke University), Brad Upham (Michigan State University), Bernie Futscher (University of Arizona), Bruce Richardson (University of Michigan), Piroska Szabo (City of Hope Cancer Center), and Frederick Tyson (NIEHS).

2009-P-182-ISES

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Epigenetics, Imprinting, and Human Disease Susceptibility

R. L. Jirtle; Duke University, Durham, NC

Human epidemiological and animal experimental data indicate that the risk of developing adult-onset chronic diseases such as cardiovascular disease, diabetes, obesity, and cancer is influenced by persistent adaptations to prenatal and early postnatal exposure to exposure to environmental conditions such as nutritional privation. Two epigenomic targets that potentially link early nutritional effects to adult disease susceptibility are imprinted genes and those with metastable epialleles. Genes with metastable epialleles have highly variable functions because of stochastic allelic changes in the epigenome rather than mutations in the genome. Genomic imprinting is an unusual epigenetic form of gene regulation that results in monoallelic, parent-of-origin dependent gene expression. It evolved in mammals with the development of the placenta and the advent of viviparity, but the process of imprinted gene formation is dynamic, allowing for both its establishment and loss during evolution. The potential importance of these two novel subsets of epigenetically labile genes in normal human variation, and the etiology of environmentally-induced diseases will be discussed.

2009-P-184-ISES

Epigenetics Links Early to Later-life Disease Susceptibility and Outcome

S. Ho; University of Cincinnati, Cincinnati, OH

Evidence is mounting that early-life exposure to environmental pollutants contributes to adverse disease outcomes in later life. The theory of developmental origin of disease stems from epidemiological studies demonstrating low birth weight as a risk factor of coronary heart disease, type II diabetes, osteoporosis, behavioral disorders, and other complex childhood, adolescent and adult diseases. Examples include gestational exposure to diethylstilbestrol and the development of reproductive abnormalities in affected individuals and the long-term behavioral impacts observed in children exposed to lead. Although many theories have been proposed to explain the early origin of human disease, the epigenetic theory is rapidly gaining ground as a mechanism underlying the phenomenon. It argues that adverse developmental conditions or specific environmental factors alter pathways of organ differentiation via epigenetic modifications of the genome. These epigenetic marks or “memories” can have long lasting effects on gene expression and functional capacity of the affected organs. Conjointly, the resulting molecular, biochemical and physiological changes brought about by an altered epigenome(s) change disease susceptibility and outcomes in individuals as well as in populations within a relatively short evolutionary time. In this presentation, through the use of relevant animal models and human specimens, we further advance the concept that specific early-life epigenetic memories can lie dormant until adulthood and then be reactivated by a specific late-life stimulus (stimuli) leading to the expression of an aberrant phenotype. This concept argues that dormant epigenetic memories induced by

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early-life exposures to environmentally active compounds may render harmless if the later-life triggers were to be identified and eliminated.

2009-P-394-ISES

Epigenetic Remodeling by Environmental Arsenicals

B. W. Futscher; University of Arizona, Tucson, AZ

Environmental exposures to arsenicals are a significant health concern to U.S. and world populations, since arsenicals are widely distributed in the environment and are involved in the etiology of a variety of human diseases, including bladder cancer. We hypothesized that arsenicals participate in human disease through their ability to disrupt normal epigenetic control. To address this hypothesis, we used human gene promoter microarrays to examine the extent and temporal nature of changes in DNA methylation and histone modification in a model of arsenical-induced malignant transformation of immortalized human urothelial cells. Our data suggest that during arsenical-induced malignant transformation, aberrant changes in DNA methylation and histone modification occurs non-randomly and progresses gradually at hundreds of gene promoters. These epigenetic changes are linked to changes in the expression of the associated gene and that these changes are coincident with the acquisition of malignant properties, such as anchorage independent growth and tumor formation in immunocompromised mice. These arsenical-induced DNA methylation and histone modification changes are stable, since malignantly transformed cells removed from exposure to the transforming arsenical exhibited no reversion in DNA methylation or histone modification state, associated gene expression, or malignant phenotype. These data suggest that arsenicals act as epimutagens and directly link their ability to induce malignant transformation to their actions on the epigenome.

2009-P-395-ISES

Epigenetic Mechanisms of Nickel Ion Carcinogenesis

M. Costa; NYU Scool of Medicine, New York, NY

Water insoluble nickel (Ni) compounds are carcinogenic due to the delivery of high concentrations of Ni ions into cells by phagocytosis and dissolution. A major target of Ni ions in cells is the iron-, ascorbic acid-, oxoglutarate-dependent dioxygenase enzymes. The newly-discovered family of histone H3 demethylases are an example of these enzymes. The reason for the specificity in the Ni inhibition is they contain loosely bound Fe within a 2-His-1-carboxylate triad termed the JMJC domain. Since Fe binding to this domain is required for catalytic activity and Ni ions readily displace the Fe from all of these enzymes, Ni exposure results in essentially inactive enzyme. Nickel ions were found to induce global DNA methylation and H3K9 methylation by inhibiting H3K9

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histone demethylase of which JHDM2A is an example. Preincubation of recombinant JHDM2A with 5 uM Ni ions essentially inactivated the enzyme since even 2000 uM Fe ions were not able to displace the Ni ions from the active site of the enzyme. A ratio of Ni ions to enzyme molecules of approximately 1:1 was required for complete inhibition. Since Ni ions are one of the least toxic metal ions, this ratio was easily achievable at levels of Ni ions that are not toxic to cells. Transfection of flag-tagged JHDM2A resulted in a loss of H3K9 Dimethylation which was prevented when cells were treated with Ni ions, indicating that this enzyme was a Ni target in cells. Ni ion exposure as well as knockdown of JHDM2A resulted in the down-regulation of a number of genes which remained low in expression for as much as 25 days after Ni ions were removed from the media, suggesting that there is epigenetic inheritance of gene expression changes brought about by Ni ion exposure. The genes that were the most stabily downregulated by Ni ion exposure had greater H3K9 Dimethylation changes in their promoter based upon Chip assays.

2009-P-396-ISES

Environmental Effects on Lupus T Cell DNA Methylation and Gene Expression

B. Richardson; University of Michigan, Ann Arbor, MI

Inhibiting DNA methylation in CD4+ T cells causes overexpression of genes normally suppressed by DNA methylation, including CD11a, IFN-?, perforin, CD70 and KIRs, and the increase is due at least in part to demethylation of their promoters. T cell DNA also demethylates with age, and aging is associated with the development of anti-nuclear antibodies in most people and lupus in a genetically predisposed subset. T cell DNA demethylation in lupus and aging is due in part to decreased ERK pathway signaling, which diminishes DNA methyltransferase 1 (Dnmt1) upregulation during mitosis and thereby impairs replication of DNA methylation patterns. DNA methylation pattern replication is also dependent on S-adenosylmethionine (SAM) levels and inhibited by S-adenosylhomocysteine (SAH). We hypothesized that exogenous agents decreasing SAM levels, increasing SAH levels, or decreasing Dnmt1 levels or activity would be synergistic in increasing expression of methylation sensitive T cell genes that contribute to autoimmunity. Decreasing folate or methionine levels, together with increasing homocysteine or decreasing Dnmt enzyme levels with ERK pathway inhibitors, caused overexpression of T cell genes in young people. Lupus patients were found to have normal methionine and folate levels but elevated homocysteine levels. In contrast, T cells from older (>60 years) people had lower Dnmt1 levels than younger controls, and restricting methionine or folate alone was sufficient to cause demethylation and overexpression of methylation sensitive genes in their T cells, and homocysteine was synergistic. These results indicate that decreases in Dnmt activity due to aging and/or xenobiotics affecting Dnmt levels or function, elevated homocysteine levels, and a diet poor in methyl donors are synergistic in affecting methylation sensitive gene expression, and may contribute to the development of lupus in genetically predisposed people.

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Symposium

M-SY102: Exposure Assessment Studies in East Asia Countries

East Asia is experiencing a unique environmental health challenges from economic growth, extraordinary advances in technology, natural disaster and environmental deterioration. Although sharing common features of global environmental health issues, this region has different aspects of problems and addresses unique approach to generate future solutions to complex environmental health problems. This symposium will provide a forum for the presentation and discussion of key environmental health issues facing researchers in East Asian countries. With new establishment of East Asia Chapter of International Society of Exposure Sciences, this forum will be a magnet for regional researchers as well as other researchers who may be interested in collaboration with this region. This symposium will consist of five presenters from three countries and introduce recent major exposure assessment studies in several East Asian Countries. 1) “Activity pattern and personal exposures to VOCs in Korean population” Wonho Yang, Daegu Catholic University, Daegu, Korea, Since personal exposure is affected by microenvironmental concentration and activity pattern, we measured activity pattern and microenvironmental volatile organic compound (VOC) concentrations along with personal exposure of 400 subjects. 2) “Change of chemical properties and released inflammatory mediators by urban air particles during the Asian dust (Yellow sand) period in Korea” Dongchun Shin, Yonsei University, Seoul, Korea The Asian dust storm travels from the China’s Gobi Desert through some of China’s biggest industrial centers, picking up pollutants such as PAHs and metals on the way. We study to analyze the chemical composition and to evaluate the cell toxicity of ambient PM10 and PM2.5 in Asian dust storm. 3) “Exposure assessment of PCBs in the current Japanese people” Chisato Mori, Graduate School of Medicine, Chiba University, Japan We will introduce the current exposure level of total PCBs in 526 Japanese people from prenatal period to 80 years old. Adult blood PCB level increased according to aging. Adult males and females without pregnant experience showed similar association pattern between age and PCB levels. On the other hand, PCB levels of females who have been pregnant were lower than those of males and females without pregnant experience during lactation period and afterward. 4) “Estimation of dietary intake of toxic substances in Japan” Satoshi Nakai, Yokohama National University, Japan It is important to evaluate exposure levels of toxic substances for risk assessment. The dietary intakes of cadmium were estimated by using Monte Carlo simulation. The data of National Nutrition Survey conducted in Japan and the data of cadmium surveillance were used as the food consumption data and cadmium concentration data. 5) “Submicron Particles Exposure at a Bus Station and a Scooter Garage in Taipei, Taiwan” Chang-Chuan Chan, College of Public Health, National Taiwan University, Taipei, Taiwan Buses and scooters are two important transportation tools in developing countries. Bus stations and parking garages are two places where high concentrations of these particles may exist in urban environment. We conducted this study to characterize number concentrations of submicron particles at a bus station and a scooter garage in Taipei, Taiwan.

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2009-P-140-ISES

Activity Pattern and Personal Exposures to VOCs in Korean Population

W. Yang; Daegu Catholic University, Daegu, Republic of Korea

Personal exposure is critical information to determine extent of risk and identify factors associated the risk. Since personal exposure is affected by microenvironmental concentration and activity pattern, we measured activity pattern and microenvironmental volatile organic compound (VOC) concentrations along with personal exposure of 400 subjects. The subjects were recruited in four different areas and the measurement was repeated in summer and winter. Activity pattern of these 400 subjects were compared with those of 32,000 subjects. The 32,000 subjects were recruited from the entire countries proportionally to the population distribution. This exposure study can provide valuable information to understand population exposure and impact from exposure-related behaviors.

2009-P-141-ISES

Change of Chemical Properties and Released Inflammatory Mediators by Urban Air Particles During the Asian Dust (Yellow Sand) Period in Korea

D. Shin, J. Yang, Y. Lim, Y. Lee, J. Jang, J. Kim; The Institute for Environmental Research, Yonsei University, College of Medicine, Seoul, Republic of Korea

The Asian dust storms appear annually and blow across most of Korea and can even reach Japan. The Asian dust storm travels from the China’s Gobi Desert through some of China’s biggest industrial centers, picking up pollutants such as PAHs and metals on the way. We study to analyze the chemical composition and to evaluate the cell toxicity of ambient PM10 and PM2.5 in Asian dust storm. The contribution ratios of hazardous metals (such as Fe, Zn, Mg, Mn) of the fine particle matter were much more than that in non-dust storm days. The dust storm PM significantly decreased the cell viability and increased the pro-inflammatory cytokine levels at low dosage. Its toxic effects might be attributed to oxidative damage mediated by pro-oxidant/antioxidant imbalance or excess free radicals.

2009-P-142-ISES

Exposure Assessment of PCBs in the Current Japanese People

C. Mori; Chiba University, Chiba, Japan

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We will introduce the current exposure level of total PCBs in 526 Japanese people from prenatal period to 80 years old. Adult blood PCB level increased according to aging. Adult males and females without pregnant experience showed similar association pattern between age and PCB levels. On the other hand, PCB levels of females who have been pregnant were lower than those of males and females without pregnant experience during lactation period and afterward. Average values of total PCBs are 0.04 ng/g-wet in cord bloods. Blood PCB levels of infants increased according to the length of the lactation period. In the case of the infants older than 2 years old, there was correlation between the length of the lactation period and blood PCB levels. Using the results of our studies, we proposed to establish the health examination system for women at reproductive age (Mori and Todaka, 2009). If women go through health examination of chemicals and if life intervention or medication is taken to those who are highly contaminated women, the risk to future babies will decrease. It will contribute to health promotion of future generation by preventing fetal and lactational exposure of POPs.

2009-P-143-ISES

Estimation of Dietary Intake of Toxic Substances in Japan

S. Nakai; Yokohama National University, Yokohama, Japan

It is important to evaluate exposure levels of toxic substances for risk assessment. The dietary intakes of cadmium were estimated by using Monte Carlo simulation. The data of National Nutrition Survey conducted in Japan and the data of cadmium surveillance were used as the food consumption data and cadmium concentration data. The 95th percentile dietary intake of cadmium was below the PTWI. In addition, Dioxins and Cadmium intake distributions among expected high-exposure groups were estimated, and a simultaneous exposure assessment for dioxins and cadmium was examined. There was no regional difference for dioxins but cadmium showing regional differences. Those whom intake of both contaminants exceeded TDI were found out in all the areas.

2009-P-144-ISES

Submicron Particles Exposure at a Bus Station and a Scooter Garage in Taipei, Taiwan

C. Chan; National Taiwan University, Taipei, Taiwan

Buses and scooters are two important transportation tools in developing countries. Potential health risks may exist for people who are exposed to diesel and gasoline particles emitted from these vehicles. Bus stations and parking garages are two places where high concentrations of these particles may exist in urban environment. We conducted this study to characterize number concentrations of submicron particles at a

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bus station and a scooter garage in Taipei, Taiwan. The Sequential Mobility Particle Sizer and Counter (SMPS+C, Grimm Model 5.403) was used to measure submicron particle number concentrations, temperature and humidity in these two locations. The count median diameters (CMD) of aerosols were 24.7-27.0 nm in the bus station and scooter garage. Averaged total number concentrations of aerosols with diameters from 11.1 to 1083.3 nm (NC11.1-1083.3) were 1.19×105 cm-3 and 1.02×105 cm-3 for bus station and scooter garage. There was significant diurnal variation in concentrations with four times difference at the bus station and 11 times difference at the scooter garage between rush hours and non-rush hours. There was positive correlation between concentrations and traffic volumes. The regression equations were: Y=1857.5X+2401.4, R2=0.5234 for the bus station and Y=162.78X+13483, R2=0.826 for the scooter garage. There was one peak of submicron particles at the bus station with NC11.1-12.1 was the highest among different sizes of NC11.1-1083.3 with the number concentration of 70100 cm-3 and 90641 cm-3 for bus station and scooter garage, respectively.

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Symposium

M-SY103: Methods and Strategies for the Assessment of Consumer Exposure: Discussion on Approaches to Improve Modeling of the Variability of Consumer Behavior

Methods and the data required to assess exposure from consumer products are still under development especially compared to the related field of worker exposure. For assessing worker exposure, closely defined and controlled situations with experienced personal are being modeled. However, consumers’ use of products is both more variable and less understood. Furthermore, the range of products a consumer can use or come into contact with is quite wide, ranging from personal cleansing products such as hand soap, to cleaning products, to home use pesticides, to clothing and furniture, etc. Furthermore, for any given consumer product individual consumers can handle these products in very different ways. For example, some users follow use instructions, some do not. Finally, some consumers use a product regularly while others never use the product in their lifetime. Under the requirements of the new European chemicals legislation REACH the assessment of consumer exposure to chemicals will gain new impetus. For registration under REACH consumer exposure scenarios have to be developed. When registering a product the exposure for all the substances constituting the product need to be assessed. Without this assessment registration will be denied. Adequate risk management measures in some cases will be needed for existing applications, and therefore insight into consumer behavior (their habits and practices of use of products) is needed for identifying and eliminating situations, which create an unacceptable consumer risk. Introducing consumer behavior into human risk assessment asks for even closer cooperation between social and natural sciences than has been practiced up to now. The goal of this symposium would be to bring together people who are already familiar with and involved in collecting consumer product habits and practices data and using them in exposure and risk assessments with people from various disciplines such as natural sciences, social sciences, and mathematics/statistics to discuss methods and strategies for improving the understanding of consumer product use, and subsequent exposure assessment. Key questions: - Where are the most critical knowledge gaps with regard to consumer behaviour? - How can these knowledge gaps be filled, are there promising methods at hand? - What can be learned from other disciplines for modeling consumer exposure?

2009-P-72-ISES

Estimating Exposure to Consumer Products: Method, Data, and Future Directions

C. E. Cowan-Ellsberry; The Procter & Gamble Company, Cincinnati, OH

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Methods and the data required to assess exposure from consumer products are still under development. Consumers’ use of products can be quite variable among consumers. For example, the range of products a consumer can use or come into contact with is quite wide, ranging from personal cleansing products such as hand soap, to cleaning products, to home use pesticides, to clothing and furniture, etc. Furthermore, for any given consumer product individual consumers can handle these products in very different ways. Finally, some consumers use a product regularly while others never use the product in their lifetime. This variability can lead to quite different exposures to products for individual consumers and makes understanding and estimating this exposure difficult. Despite this wide range of issues and questions related to how to estimate consumer exposure, there is a need under existing and emerging regulations to generate estimates of these exposures in order to evaluate whether chemicals used in these types of products are safe. To meet this need, industry has been developing and publishing habits and practices data for various types of consumer products. This presentation will discuss the methods used to obtain data to understand and quantify how consumers handle products and how these could potentially vary with age, ethnicity, and sex. The strengths and limitations of these various approaches are discussed and the public sources for these data described.

2009-P-73-ISES

Modeling the Variability In Consumer Product Use Patterns

P. Williams; E Risk Sciences, LLP, Boulder, CO

Consumer product exposure and risk assessment is of growing importance due to REACH internationally as well as other programs within the United States. In this presentation we will address several aspects related to the development of exposure scenarios and analyses that incorporate the variability in consumer product use patterns among different population groups. Specifically, we will discuss: (1) tiered approaches to exposure assessment, (2) existing consumer product models and software tools, and (3) exposure factors and computation methods often used to evaluate occupational exposures to different solvents and products. For example, one of the most important statistical methodologies in assessing consumer product use scenarios is the use of probabilistic (Monte Carlo) techniques. Probabilistic analyses are particularly useful when there is significant variability among consumer products, use patterns, and activities and uncertainty in exposure factors (such as in the use of professional judgment to fill data gaps). The use of higher-tired analyses will be contrasted with screening-level techniques that are used in lower-tiered assessments, and criteria for when to use simpler versus more refined tools will be discussed. Additionally, we will discuss some of the strengths and limitations of existing consumer product models and software tools, such as CONSEXPO, CARES, SHEDS, and E-FAST, for use in consumer product exposure and risk assessments. Finally, we will describe exposure factors and computational methods commonly used to assess occupational exposures from various product releases that may be useful for evaluating consumer product exposures.

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2009-P-74-ISES

Modeling Consumer Behavior Variability for the Assessment of Aggregate Consumer Exposure to Chemicals

N. von Götz; ETH Zurich, Zurich, Switzerland

Consumers are exposed to chemicals from various sources via different pathways. Additionally, consumer exposure mostly is influenced by consumer behavior, which can be highly variable. For modeling the total or an aggregate consumer exposure to a chemical it is necessary to significantly reduce the complexity of the relationship between substance and consumer. Therefore, the sources of the substance as well as the consumers have to be grouped in a meaningful way. Ideally, the groups should be homogenous concerning the factors of highest impact. For example, a product group for the exposure assessment to lipophilic substances might consist of all fatty food or a consumer group might consist of consumers sharing a specific behavior critical for substance uptake. In reality, group segmentation will also depend on data availability and groups constructed for data generation. In many cases age and gender are the most influencing factors not only for consumer physiology but also for consumer behavior. For exposure assessment, however, also sector specific sources and activities have to be taken into account, which may impose further differentiation of age and gender based consumer groups. Exposure to engineered nanoparticles from cosmetics, for example, differs significantly between consumers of similar age and gender, depending on their behavior patterns. The least exposed non-users contrast with the highly exposed very frequent users. Here, we constructed comparatively small and homogenous distinct consumer groups basing on detailed market research data on consumer behavior and calculated exposure levels for each consumer group. Apart from forming distinct consumer groups another possibility of quantitatively taking into account consumer behavior variability is to use distribution functions for the consumer behavior. This probabilistic approach is illustrated with the example of assessing an aggregate consumer exposure to brominated flame retardants.

2009-P-76-ISES

What Do Consumer Research and Exposure Assessment Offer Each Other?

J. Scholderer; Aarhus School of Business, Aarhus University, Aarhus, Denmark

Consumer researchers have a long tradition of collecting data that can be useful in the construction of exposure scenarios. The data used in consumer research are always multivariate, often representative, and either collected from household panels (longitudinal), product use surveys (cross-sectional) or preference and choice studies (experimental). The typical structure of such data sets will be demonstrated, including the most common types of measures. Major sources of uncertainty and variability will be discussed, together with state-of-the-art approaches for their modelling. The emphasis

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will be on latent variable and finite mixture models. Furthermore, heuristic tools such as usage situation mapping will be demonstrated which can be helpful for identifying sources of heterogeneity.

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Symposium

M-SY104: Enhancing Exposure Assessment for Air Pollution Health Studies: EPA/NERL Cooperative Agreement Program

The objective of this symposium is to explore and discuss the development and application of alternative and refined approaches to exposure assessment techniques in air pollution health studies for PM, PM species, ozone and other co-pollutants. Since direct personal exposure measurements on all or most of the health study subjects cannot be practically obtained, it is important to consider various alternative surrogates or indicators of exposures -- ranging from simple to more complex (e.g., monitoring data, GIS-based kriging or land-use regression modeling, regional and local-scale air quality modeling, data fusion methodologies, surrogates for air exchange, infiltration or other exposure factors, and probabilistic exposure models), depending on the particulars of the epidemiologic study design and availability of exposure-related information. Based on the design of the epidemiological study adopted and the sophistication of the exposure estimation approach selected, different levels of exposure misclassification may be introduced during the course of air pollution health effects analysis. A number of different surrogates for personal exposures have already been used in criteria air pollution epidemiology studies but new and improved approaches for estimating exposures are emerging. The 2009 ISES conference provides a timely opportunity for the exposure and epidemiological communities to discuss the advantages and limitations of various exposure assessment techniques employed during ongoing or anticipated future investigations of air pollution health effects. This symposium consists of a total of six overview and project-specific presentations focusing on predictors of exposures to PM2.5, PM2.5 components and gaseous co-pollutants. The presentations will be based on the early findings from the recently initiated two-year Cooperative Agreement program (the “Air Pollution Exposure and Health Program”) with Emory University, Rutgers and University of Washington. The health outcomes considered will be obtained from both population level data (e.g. zipcode or MSA level) data sets (such as emergency department visits, myocardial infarctions) and cohort study data (e.g., birth outcomes, implantable cardioverter defibrillators, MESA and WHI study subjects). Presenters will emphasize lessons-learned from their studies and how these results may provide insights into future exposure and health effects studies.

2009-P-87-ISES

Overview of EPA/NERL Cooperative Agreement Research Program on Air Pollution Exposure and Health

H. Özkaynak; USEPA, RTP, NC

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National Exposure Research Laboratory (NERL) of US EPA’s Office of Research and Development (ORD) recently initiated a two-year Cooperative Agreement Research Program between EPA and three academic Institutions in the US: Emory University., Rutgers University and University of Washington. The overall goal of this “Air Pollution Exposure and Health Program” is to enhance the results from epidemiologic studies of ambient PM and gaseous air pollution through the use of more reliable approaches for characterizing personal and population exposures. The main objectives of research carried out under this Coop program are, to: 1) develop and apply innovative approaches for exposure prediction by utilizing available or modeled information based on monitoring data, meteorological data, exposure factors data, air quality and exposure modeling results, and 2) conduct analyses of available health data using the various tiers and alternative exposure metrics developed. The research goals each of the academic groups funded by EPA/NERL under this new Cooperative Agreement Program are highly complimentary. The Emory/Georgia Tech University group is in the process of developing and evaluating five exposure metrics for ambient traffic-related (CO, NOx, PM2.5 and PM2.5 EC) and regional (O3 and SO42-) pollutants in Atlanta. They will then be applying these exposure metrics to two ongoing Emory epidemiologic studies examining ambient air pollution and acute morbidity in Atlanta, GA. TheRutgers/EOHSI-LBL group is examining associations between PM2.5 mass and species and adverse health for two established epidemiology studies using different tiers for exposure specification. The University of Washington team is attempting to improve PM2.5 air pollution epidemiology study health effect estimates through exposure modeling, particularly with respect to spatially varying exposure to PM2.5 and NOx. This presentation will provide an overview of the different exposure tiers that are being developed by these academic groups and the specific health data sets which these alternative PM2.5 mass and species, and gaseous air pollution exposure surrogates will be applied during the ongoing two-year EPA/NERL sponsored assistance program.

2009-P-90-ISES

Examining Associations Between Traffic-related and Regional Air Pollution and Acute Health Using Alternative Exposure Assignment Methods

J. A. Sarnat,1 S. E. Sarnat,1 M. Klein,1 J. Mulholland,2 A. G. Russell,2 W. D. Flanders,1 L. A. Waller,1 P. E. Tolbert1; 1Emory University, Atlanta, GA, 2Georgia Institute of Technology, Atlanta, GA

Our analysis explores variability in acute health risk estimates when using alternative metrics of exposure that vary in their degree of spatial resolution. Specifically, we examine associations between traffic-related (CO, NO2, EC) and regional (O3, SO42-) pollutant exposure metrics and two acute adverse health outcomes, cardiorespiratory emergency department (ED) visits and cardiac events in patients with implantable cardioverter defibrillators, in Atlanta, GA. Our exposure metrics address various tiers of exposure refinement, including the use of 1) ambient receptor data, 2) emissions data, and 3) exposure factors data. Our previous epidemiologic results for associations involving

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ambient fixed-site monitoring data suggest that monitoring site location and the distance of a monitoring site to a population of interest do not meaningfully impact estimated associations for any traffic-related or regional pollutant when using data from urban sites located within 20 miles from the population under study (Sarnat et al. in press). This finding supports use of pollutant data from an urban central site to assess population exposures within a geographically dispersed study population. However, for CO and NO2, these factors were important when using data from sites located greater than 30 miles from the population, likely due to exposure measurement error. In our current analyses, we focus on alternative exposure metrics for these traffic-related pollutants and we also consider factors that could potentially lead to differences in health effect estimates, including spatial variation of pollutant-specific personal-ambient relationships (e.g., due to differential infiltration patterns). Here, we will present and compare the results of several analyses using our alternative exposure metrics. We will also discuss the benefits of using increasingly detailed exposure assessment approaches in air pollution epidemiology as well as interpretations and limitations of each exposure assignment method.

2009-P-92-ISES

Resolving the Intra-Urban Air Pollution Field by Fusing Grid- and Point-Based Air Quality Models and Ambient Monitor Observations

J. L. Crooks,1 S. E. Sarnat,2 J. Sarnat,2 J. Mulholland,3 A. G. Russell,3 H. Özkaynak,1 V. Isakov1; 1US EPA, RTP, NC, 2Emory University, Atlanta, GA, 3Georgia Tech University, Atlanta, GA

Recent interest in near-road exposure to air pollutants and related health and environmental justice issues has engendered a desire to improve the accuracy of ambient exposure estimates by resolving the intra-urban concentration field. Unfortunately, except in rare cases no single source of information can accurately estimate the ambient concentration at the spatial and temporal resolution and over the time period that is required. However, it is possible to combine information from several sources so as to exploit the strengths and offset the weaknesses of each and thus produce accurate estimates. Specifically, we can combine data from ambient monitors with output from computer models of known physical and chemical processes. Monitor networks are sparse in both space and time, are costly to maintain, and are often designed purposely to avoid detecting local features. Two types of computer models can compensate for these drawbacks. One type, grid-based regional photochemical simulations such as CMAQ, yield data for large areas at high time resolution but cannot resolve features smaller than a grid cell, usually a few or a few tens of kilometers across. The second type, plume dispersion models such as AERMOD, can resolve these features but cannot track long-range transport or chemical reactions. We present a new Bayesian method that blends these three sources of information to resolve the intra-urban pollution field. This method represents the latent field using a 2D wavelet basis, which allows direct, efficient comparison to data at of multiple types and at multiple levels of resolution. We use it to

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estimate daily Atlanta-area 1 hour maximum PM2.5 concentration at census block-group centroids for the year 2002.

2009-P-97-ISES

Refined Exposure Surrogates for Ambient PM in Epidemiology Studies: Accounting for Temporal/Spatial Variations in Infiltration

B. Turpin,1 M. Lunden,2 H. Özkaynak,3 T. Barzyk,3 J. Burke,3 L. Baxter,3 D. Rich,4 L. Kamat,4 P. Ohman-Strickland4; 1Rutgers University, New Brunswick, NJ, 2Lawrence Berkeley National Laboratory, Berkeley, CA, 3US EPA, RTP, NC, 4Robert B. Wood Johnson University/EOHSI, New Brunswick, NJ

Outdoor fine particulate matter (PM2.5) mass/species concentrations are frequently used as surrogates of exposure to outdoor-generated PM2.5. However, human exposure to outdoor-generated PM differs from central site PM because of variations in outdoor concentrations, human activity patterns, particle losses with outdoor-to-indoor transport, and losses in indoor spaces. People spend the vast majority of time in indoor environments, and particle infiltration (the penetration of outdoor particles into indoor spaces and their persistence indoors) varies spatially and temporally due to variations in air exchange rate/ housing stock/ventilation practices and variations in particle properties/source mix. This presentation examines two modeling approaches that can be used to modify central site PM2.5 to account for particle infiltration. Other refinements, for example time-activity data, will be considered as well. We plan, ultimately to use these refined exposure surrogates in two epidemiology studies: The New Jersey (NJ) Triggering of Myocardial Infarction (MI) Study and the NJ Adverse Birth Outcomes Study. This paper uses field measurements to illustrate a variety of reasons why the relationship between actual exposure and an exposure surrogate (Central site PM2.5) can vary spatially and temporally, and examines potential limitations and prospects for providing refined exposure surrogates that account for these processes. Ultimately, use of more accurate exposure surrogates should lead to reduced uncertainties in exposure and risk estimates. These, in turn, facilitate more effective exposure/risk mitigation strategies for public health protection.

2009-P-93-ISES

Modeled Estimates of Personal Exposure to PM2.5 Compared to Ambient Measurement Records and an Assessment of Contributing Factors that Account for Deviations

T. M. Barzyk, J. Burke, L. Baxter, H. Özkaynak; US EPA, RTP, NC

The population-based Stochastic Human Exposure and Dose Simulation model (SHEDS) estimates personal exposures to PM2.5 mass and species. For each exposure factor,

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SHEDS uses a probabilistic approach to randomly sample from distributions of available data to predict the distribution of exposures for the population of interest. Two important exposure factors include human activity patterns based on the Consolidated Human Activity Database, and regional estimates of air exchange rates (AER), neither of which are included when ambient measurements are used as surrogates for personal exposure. SHEDS will be applied to two New Jersey cohorts, and the personal exposure estimates for each cohort will be used as inputs for epidemiological analyses, one addressing myocardial infarctions, and another adverse birth outcomes. This presentation focuses on the comparison between SHEDS personal exposure estimates and ambient measurements of PM2.5 recorded within 10 km of cohort participants. Several factors will be assessed to determine which ones cause SHEDS estimates to deviate from ambient records, including human activity patterns and AER. A refined methodology for producing and incorporating localized estimates of AER will also be examined. This work supports a cooperative agreement between the Environmental Protection Agency (EPA) and Rutgers University that investigates associations between air pollution and health using alternative estimates of human exposure.

2009-P-96-ISES

Spatio-temporal Estimation for Improved Exposure Assessment in Epidemiological Studies

P. Sampson,1 A. Szpiro,1 J. Lindstrom,1 L. Sheppard2; 1University of Washington, Seattle, WA, 2University of Washington, Seatlle, WA

This work is motivated by the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air), a cohort study funded by the U.S. Environmental Protection Agency (EPA). MESA Air exposure assessment emphasizes accurate prediction of individual ambient-source exposures in order to accomplish its primary aim of assessing the relationship between chronic exposure to air pollution and progression of sub-clinical cardiovascular disease. Air pollution cohort studies have increasingly used predicted ambient air quality based on GIS-based covariates in "land use regression" models, and more recently some studies have used predicted exposure from spatial regression models to account for spatial correlation structure. However, few exposure prediction models have also incorporated the temporal structure in air pollutant concentrations in a spatio-temporal framework. Furthermore, most geostatistical and/or land use regression methods in the literature are not applicable to the MESA Air study because they require a nearly complete space-time data matrix. We build on geostatistics concepts to provide spatio-temporal predictions of ambient pollutant concentrations in MESA Air and other air pollution cohort studies. The model incorporates spatially varying seasonal trends and complex spatial correlation structures. This research performed under the EPA/NERL exposure and health cooperative agreement extends the MESA Air spatio-temporal model to integrate new sources of information, specifically deterministic air quality model output and sub-grid scale predictors.

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Symposium

M-SY201: Environmental Influences on Epigenetic Processes and Complex Diseases II

A concerted effort has been made by the research community to merge toxicology research with studies of epigenetic mechanisms resulting in the materialization of exposure biology studies that focus on environmental toxins impact on known epigenetic mechanisms or marks, primarily DNA methylation and histone modifications to influence the pathogenesis of complex human diseases. Some aspects of exposure influenced epigenetic aberrant processes NIEHS supported scientists are studying include: • defining the role of CpG island methylation of tumor suppressor genes in the development of human adenocarcinoma of the lung and the influence of environmental exposures on which genes are targeted; • asking whether in utero exposure to an environmentally relevant dose of arsenite accelerates puberty onset and alters mammary gland development; • testing a hypothesis that perinatal exposure to persistent organic polybrominated diphenyl ethers (PBDE) may result in epigenetic changes in developing neurons that impact the development of social and cognitive behavior; • using unbiased epigenetic profiling coupled to high-resolution confirmatory approaches to address the hypothesis that environmental arsenicals act as epimutagens – toxicants that form aberrant epigenetic states that are maintained and heritable even in the absence of the initiating toxicant. • testing the hypothesis that exogenous agents decrease S-adenosylmethionine (SAM) synthesis and dinucleotide methyltransferase1 (Dnmt1) levels or activity would be additive or synergistic in increasing expression of methylation sensitive T cell genes and contribute to the development of autoimmunity; • testing the hypothesis that developing germ cells, which undergo genome-wide epigenetic reprogramming, are especially vulnerable to the epigenetic effects of endocrine disruptors; • the impact of low-dose exposures to ubiquitous environmental estrogens and effect on the prostate epigenome during development and, as well as, promotion of prostate disease with aging; and • exploring whether transplacental exposure to PAHs in humans induces epigenetic reprogramming involving aberrant DNA methylation of specific genes that might be mechanistically related to childhood asthma or airway inflammation; The session also will provide a brief update on the NIH Roadmap Epigenome Program. Confirmed presenters for this proposed session are: Steven Belinsky (Lovelace Respiratory Research Institute), Max Costa (New York University), Shuk-Mei Ho (University of Cincinnati), Mary Beth Martin (Georgetown University), Randy Jirtle (Duke University), Brad Upham (Michigan State University), Bernie Futscher (University of Arizona), Bruce Richardson (University of Michigan), Piroska Szabo (City of Hope Cancer Center), and Frederick Tyson (NIEHS). Additionally Janine LaSalle (University of California-Davis) has been invited.

2009-P-397-ISES

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Effect of Endocrine Disruptors on the Epigenome of Fetal Mouse Germ Cells

P. E. Szabo; Beckman Research Institute, Duarte, CA

Several hormone-like synthetic chemicals act as endocrine disruptors, and some have been shown to cause aberrations in epigenetic regulation. Exposure of pregnant mothers to endocrine disruptors can affect not only the mother and the embryo/fetus inside the mother’s uterus but also the developing germ cells inside the embryo/fetus. We hypothesized that developing embryonic/fetal germ cells, in fact, might be especially vulnerable to hormone-like substances, because these cells undergo genome-wide epigenetic remodeling. These remodeling events include the erasure and reestablishment of global DNA methylation and also histone composition patterns. It is critical to look for epigenetic changes in germ cells after exposure to endocrine disruptors. If aberrant methylation is induced in germ cells, it can affect gene expression and cell function, development and fertility, and, importantly, may also be transmitted to consecutive generations. To determine possible epigenetic perturbations caused by endocrine disruptors, we treated pregnant females with di-(2-ethylhexyl)-phthalate (DEHP), bisphenol A (BPA) or vinclozolin (VIN), then purifed embryonic and fetal germ cells and assessed the transcriptional profile of these cells using RNA microarrays. To find aberrant hyper- or hypo-methylation at a global level we pulled down methylated CpG rich regions from normal and in in utero exposed male and female germ cells, using the methylated-CpG island recovery assay (MIRA) assay and hybridized these DNA fragments to CpG island microarrays and genomic tiling microarrays. Our findings and their implications will be discussed.

2009-P-187-ISES

Arsenite and Epigenetic Regulation of Gene Expression

M. B. Martin; Georgetown University, Washington, DC

Endocrine disruptors are thought to be an underlying cause for the high incidence of hormone related diseases such as early puberty onset and breast cancer. Published studies from this laboratory demonstrate that the metalloid arsenite activates ER? through a high affinity interaction (Ki = 10-10 M) with the hormone binding domain of the receptor involving amino acids C381, C447, H524, K529 and/or K531, andN532. More importantly, we have shown that an environmentally relevant dose of arsenite mimics the effects of estradiol on the growth and expression of genes in MCF-7 breast cancer cells.

2009-P-398-ISES

Environmental Gene Repression Can Induce Aberrant Epigenetic Silencing

M. Turker; Oregon Health & Science University, Portland, OR

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Aberrant epigenetic silencing plays a causal role in cancer because it leads to tumor suppressor gene inactivation. However, the initiating events of silencing are not known. Gene repression, which occurs commonly from a variety of environmental exposures, can cause repressive histone modifications. We therefore hypothesized that transient and reversible gene repression could trigger aberrant epigenetic silencing and conducted a series of experiments to test this hypothesis. For a proof of principle experiment, a tetracycline (tet) repressible promoter (pTRE) was ligated to the selectable human HPRT cDNA and transfected stably into a mouse cell line. Results from these experiments demonstrated the histone deacetylation was required for repression-induced silencing and that DNA methylation was a secondary event. We next tested repression-induced silencing with a bona fide tumor suppressor promoter, BRCA1 using a 218 bp bidirectional BRCA1 promoter fragment. Mouse Aprt was ligated in place of the upstream transcript (NBR2) and HPRT cDNA was ligated in place of the downstream transcript (BRCA1). The Aprt-BRCA1-HPRT construct was transfected stably into the mouse cells and hypoxic conditions shown to induce silencing of the HPRT transcript without causing silencing of the Aprt transcript. This result showed that hypoxia could induce silencing of the BRCA1 promoter, but that silencing was unidirectional. A similar result of unidirectional inducible silencing was obtained when CoCl2 was used to repress the BRCA1 promoter. Therefore, the 218 bp BRCA1 promoter can simultaneously support both a silenced transcript and an expressed transcript. In conclusion, a transient repression in promoter expression can induce aberrant epigenetic silencing. The implications of these results for a novel epigenetic relation between cancer and environmental exposure will be discussed.

2009-P-188-ISES

Key Roles of Gap Junctional Communication in the Toxico-epigenomics of Chronic Diseases

B. L. Upham; Michigan State University, East Lansing, MI

Epigenetic mechanisms control the expression genes that regulate cell proliferation, differentiation, apoptosis, senescence and adaptive responses of cells in a multicellular organism. These mechanisms involve alteration in gene expression at the transcriptional, translational and posttranslational levels in stem, progenitor (transit-amplifying) and terminally differentiated cells. Three intricately connected communication processes, namely extra-, intra-, and gap junctional inter-cellular communication (GJIC) transfer signaling ions/molecules to trigger signal transduction between and within cells. Both endogenous (hormones, growth factors, cytokines, etc.) and exogenous (pollutants, drugs, toxins, food additives, etc) can act as extra-cellular triggers of many intra-cellular signaling pathways within a cell that can (a) modulate (increase or decrease) GJIC between cells and cause intracellular changes leading to altered gene expression. From the single fertilized egg to the mature adult containing 100 trillion cells, normal development and maintenance of homeostatic health is dependent on a balance these communication processes with GJIC playing a central regulatory role. Disruption of cell

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communication via a number of different mechanisms in (a) embryonic and fetal development, leading to birth defects; (b) during sexual maturation/germ cell development leading to reproductive dysfunction; (c) “initiated” organs can promoter tumor growth; (d) brain tissues causing neurotoxicities and (e) immune tissue can lead to immunotoxicities. Today, many environmental toxicants/toxins , which can contribute to multiple pathologies, such as DDT, PCBs, PBBs, PAHs, PFOA, TCDD, bis-phenol A, are known to act via epigenetic mechanisms. Thus, we have used GJIC to anchor our functional genomic studies, particularly at the proteome level, to map out novel signaling pathways activated in response to environmental toxicants.

2009-P-462-ISES

NIH Roadmap Epigenomics Program

F. L. Tyson; NIEHS, RTP, NC

The overall hypothesis of the NIH Roadmap Epigenomics Program is that the origins of health and susceptibility to disease are, in part, the result of epigenetic regulation of the genetic blueprint. Specifically, epigenetic mechanisms that control stem cell differentiation and organogenesis contribute to the biological response to endogenous and exogenous forms of stimuli that contribute to normal health, development, aging, and disease. The program is addressing the hypothesis with five integrated research elements. The reference epigenome mapping centers (REMCs) are developing comprehensive reference maps of known epigenetic marks, e.g., DNA methylation, various histone modifications, and non-coding RNAs for a number of cell types, including human embryonic stem cells, induced pluripotent stem cells, and selected differentiating and differentiated cells relevant to human disease. The technology and development component is developing technologies that will revolutionize epigenetic profiling and/or whole epigenome studies. The novel marks program supports research to identify stable, long term changes in epigenetic processes and establish the utility of these marks in mammalian cells. The health and human disease component of Roadmap program is supporting research on fundamental epigenomic changes or mechanisms underlying specific diseases; conditions of development or aging; or response to exposures (physical, chemical, behavioral, and social factors). The Epigenomics Data Analysis and Coordinating Center (EDACC) is providing data analysis and coordination for all of the REMCs, as well as importing all other Roadmap Epigenomics Program data generated outside of the mapping centers. In addition, the EDACC is responsible for coordinating with the National Center for Biotechnology Information (NCBI) to develop and implement a data pipeline for transferring and tracking standardized data to NCBI for banking and public utility.

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Symposium

M-SY202: Cookstove Intervention and Indoor Air Pollution Studies in the Developing World – Exposure Assessment and Health Impact - Session A

Target Audience: indoor air pollution exposure assessment/environmental epidemiology researchers, clinicians, other researchers interested in exposure to woodsmoke and related indoor air pollution from cookstoves and replacement intervention stoves in the developing world. Objectives: 1. To review the state of the knowledge regarding recent and current cookstove intervention studies and programs in the developing world – including exposure assessment and environmental epidemiologic aspects of these programs; 2. to review lessons learned from past cookstove intervention studies and programs, including exposure assessment tools, health outcome evaluation, stove design/installation/maintenance issues, and policy related issues. Summary of session content: It is estimated that around 50% of the world’s population, with as many as 90% in some developing countries, rely on biomass fuels (wood, dung, and crop residues), which are typically burnt in open stoves, for cooking and sometimes heating. Such small-scale open combustion of biomass fuels results in extremely high levels of indoor air pollution, including particles; thus, on a worldwide basis, it is these populations that have the greatest exposures. It is hypothesized that high exposures to emissions from biomass cooking and heating fuels is a risk factor for low birth weight, acute respiratory infections (ARI) and other forms of ill-health in the developing world. This symposium will review recent developments in the area of cookstove intervention programs in recent past or currently ongoing – with a specific focus on investigations of adverse health effects associated with exposure to emissions from biomass cooking and reduced exposures and improved health in these settings related to newly installed replacement intervention stoves. Policy implications will also be discussed.

2009-P-575-ISES

An Overview of Biomass Cookstove Intervention Programs Around the Developing World

L. P. Naeher; University of Georgia, College of Public Health, Dept of Environmental Health Science, Athens, GA

(10 minutes)

2009-P-579-ISES

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Socio-demographic Characteristics and Principal Cooking Fuel Type in Sri Lanka: Analysis of the Demographic and Health Survey Data

Y. Sumal Nandasena,1 A. R. Wickremasinghe,1 N. Sathiyakumar2; 1Department of Public Health, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka, 2Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL

(15 minutes) Introduction: Indoor air pollution is a growing public health concern due to its well documented ill effects. Biomass cooking fuel is the main source of indoor air pollution in the majority of households in the developing world. Methods: Determinants and the use of cooking fuel in households in Sri Lanka were abstracted from data collected by the Demographic Health Surveys (DHS) of 2000 and 2007. The DHS was based on a representative sample of the whole country except the provinces afflicted by the war. The results are based on a sample of 8169 households in year 2000 and 19,862 households in year 2007. Results: Firewood was the principal type of cooking fuel in 78.3% and 79.6% of households in 2000 and 2007, respectively. In 2007, 96.3% of estate sector households used firewood as compared to 84.2% in the rural sector and 34.6% in the urban sector. Similar trends were seen in year 2000 as well. In 2000, electricity was the main source of lighting in 68% households; in 2007, electricity was used for lighting in 81.5% of households. In 2000, 25.9% of the houses having electricity used clean fuel, the rest relying on biomass or kerosene. The higher the educational level of the respondent, the more likely the household will use a clean fuel (p<0.001). Conclusion: The shift from firewood to cleaner fuels in Sri Lanka is negligible from 2000 to 2007. Improving the quality of life and economic status of the population does not predict a shift towards the use of cleaner cooking fuels.

2009-P-580-ISES

Biomass Use and Indoor Air Quality in Roma Villages in Slovakia and Romania - Results from the IARQ-ROMA Study

M. Majdan,1 A. Coman,2 E. Gallova,1 J. Duricov,1 L. Bosak,1 A. Brizaniuc2; 1Trnava University, School of Public Health, Trnava, Slovakia, 2Babes-Bolyai University, School of Public Health, Cluj-Napoca, Romania

(15 minutes) Background Large part of the Roma population in Slovakia and Romania lives in segregated villages without standard infrastructure in houses built of wood and mud. They are dependent on biomass as fuel for heating and cooking. Especially in winter they spend the majority of the day inside the house and is exposed to pollutants from biomass burning. Objectives

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The objective of this study was to assess the quality of the indoor air of houses in a Roma village in Slovakia and Romania during the winter season and during summer. We hypothesized that the concentration levels are higher in winter and thus the exposure is increased during this season. Methods Using the GrayWolf IQ410 indoor air quality probe we have measured a log of carbon monoxide and carbon dioxide levels, temperature and relative humidity in 17 houses in a Slovakian Roma village in winter (February) and in summer (late May) and in 11 houses in a Romanian Roma village in winter (February). One measurement took from 5 to 10 minutes with a concentration measured every 10 seconds. We divided every house into quarters or halves depending on the size and did separate measurements in every part. Results The median levels of CO in Slovakian houses ranged in winter from 1.1 to 19.7 mg/m3 and in summer from 0.4 to 2.65 mg/m3. In Romania the CO levels ranged from 2.8-17.8 mg/m3. We found significant differences in medians of CO levels measured in the same houses in winter and summer in Slovakia (p<0.001 in all 17 houses). The medians of CO2 levels ranged in Slovakia in winter from 1684 to 2811936 mg/m3 and in summer from 978-1664 mg/m3. The differences between summer and winter were significant (p<0.001 in all 17 houses). The medians of CO2 levels in Romania ranged in winter from 727 to 3551 mg/m3. Median relative humidity in Slovakia ranged from 29-97% in winter and 31-64% in summer and in Romania from 39-44% in winter. Summer measurements have not been done yet in Romania. The majority of houses comprised of a single room serving as kitchen, living room and bedroom. The chimney outlets in many cases end up in attics and do not exhale the smoke outside. The windows are often broken and can not be opened. Conclusions Although continuous sampling is not feasible in the settings included in the study, based on a series of short-term point measurements we found significant differences in levels of CO and CO2 between summer and winter in Slovakia. As the inhabitants spend the majority of the day inside the house, the total exposure burden may get significant (especially in sensitive populations such as children or pregnant women). Based on observations we conclude that the situation might be improved by relatively simple and cheap measures such as better isolated chimney outlets or windows allowing better ventilation.

2009-P-576-ISES

Baseline Air Pollution and Health Assessments for an Improved Cookstove Intervention Study in a Rural Nicaraguan Community

M. L. Clark,1 H. Bazemore,1 S. J. Reynolds,1 J. M. Heiderscheidt,1 A. Shaw,2 S. Conway,2 J. Volckens,1 J. L. Peel1; 1Colorado State University, Fort Collins, CO, 2Trees, Water & People, Fort Collins, CO

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(15 minutes) Introduction: Cooking in many developing countries usually consists of burning solid fuels over open fires or in traditional stoves that emit high levels of air pollutants. Large variations in air pollutant concentrations have been reported within stove types. Several respiratory endpoints have been associated with these exposures, although little research has been performed on cardiovascular health. Methods: We conducted the baseline assessment of an improved cookstove intervention among 130 households using traditional cookstoves in Granada (El Fortin neighborhood), Nicaragua. Indoor carbon monoxide (CO) and particulate matter (PM2.5) concentrations were assessed for 48 hours in each home. Health endpoints were assessed in nonsmoking primary household cooks. Dried blood spot samples were collected and stored for future analysis of inflammatory markers. Results: Mean 48-hr concentrations were 1478.3 µg/m3 (standard deviation [SD], 2270.7) and 26.6 ppm (SD, 24.4) for PM2.5 and CO, respectively. PM2.5 and CO were correlated with each other (48-hr mean, r=0.76). The average age of the primary cooks was 35.6 years (SD, 16.1). Average body mass index was 28.1 kg/m2 (SD, 6.7). The women cooked an average of 19.2 meals per week and spent 4.4 hrs in the kitchen while the fire was burning. Symptoms of cough, phlegm, wheeze, and headache during cooking were reported among 21.4%, 18.4%, 21.4%, and 61.1%, respectively. Doctor diagnosed asthma, chronic bronchitis, and cardiovascular disease was reported among 12.4%, 9.1%, and 9.1%, respectively. Mean FEV1 was 2.40 L (SD, 0.57); mean oxygen saturation was 97.6% (SD, 0.9); and mean systolic and diastolic blood pressure were 121.6 mmHg (SD, 22.0) and 76.5 mmHg (SD, 13.0), respectively. Conclusion: Elevated air pollution concentrations with large variations were observed among households using traditional stoves. Baseline exposure and health endpoints will be examined in relation to follow-up measures assessed after the introduction of the improved stoves.

2009-P-581-ISES

Testing the Effectiveness of Two Improved Cookstove Interventions in the Santiago de Chuco Province of Peru

C. Fitzgerald,1 M. Aguilar-Villalobos,2 S. Rathbun,3 L. P. Naeher1; 1The University of Georgia, College of Public Health, Department of Environmental Health Science, Athens, GA, 2Asociación del Aire Ambiental, Lima, Peru, 3The University of Georgia, College of Public Health, Department of Epidemiology and Statistics, Athens, GA

(15 minutes) Three Andean communities within the Santiago de Chuco province of Peru received two different models of improved cookstoves; one from the Juntos National Program (stove 1) and one from Barrick Corporation, as provided by its community relations area (stove 2). The impact of these stoves in reducing personal exposures and kitchen concentrations of particulate matter (PM2.5) and carbon monoxide (CO) was evaluated separately in 64 homes (32 homes with each stove model) with the use of air monitoring equipment. Due to a variety of study subject issues, some homes in each community were lost to follow-up over the course of the study, and only homes with complete pre- and post-intervention

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data were included in the final analyses. In the community receiving stove 1, baseline aggregate 48-hr personal exposure (n = 27) and kitchen concentrations (n = 26) of PM2.5 were 116.4 and 207.3 µg/m3, respectively, and 48-hr personal (n = 25) and kitchen (n = 25) CO levels were 1.2 and 3.6 ppm. After introducing the new stove to this community, exposures to PM2.5 reduced to 68.4 and 84.7 µg/m3, and exposures to CO reduced to 0.4 and 0.8 ppm, representing reductions of 41.3%, 59.2%, 69.6% and 77.7%. In the communities receiving stove 2, corresponding pre-intervention levels of PM2.5 were 126.3 µg/m3 (n = 18), 173.4 µg/m3 (n = 19), and CO levels were 0.9 ppm (n = 19), and 2.6 ppm (n = 17). After installation of new stoves, levels of PM2.5 reduced to 58.3, 51.1 µg/m3 and levels of CO to 0.6, 1.0 ppm. Overall, homes receiving stove 2 saw reductions of 53.8, 70.5, 25.8 and 63.6%. All values are statistically significant (p < 0.05) with the exception of personal CO reductions in the stove 2 community. Both stoves were effective at improving indoor air quality.

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Platform

M-PL201: Climate, Exposure, and Health

2009-A-392-ISES

Public Health Impacts Of Climate Change In Washington State: Projected Mortality Risks Due To Heat Events And Air Pollution

R. A. Fenske, E. Jackson, M. G. Yost, C. Karr, R. A. Rosenblatt; University of Washington, Seattle, WA

Health effects from heat and worsening air quality are core public health concerns. We examined the relationship (1980-2006) between mortality and heat events in Washington State to determine relative risks, and applied these to population and climate projections for 2025, 2045 and 2085. We found a significant dose-response relationship between heat event duration and daily non-traumatic mortality rate in the Seattle area for persons aged 45 and above, peaking at four days of exposure to humidex values above the 99th percentile. Using a moderate warming scenario, those 65 and older are expected to have 96, 148, and 266 excess deaths in 2025, 2045 and 2085, respectively. Excess deaths due to ground-level ozone concentrations were estimated for 2045-2054 in King and Spokane counties. Daily maximum 8-hour ozone concentrations were forecasted to increase 16-28%, resulting in increased total non-traumatic ozone mortality rates from baseline (per 100,000) of 0.026 to 0.033 for King, and 0.05 to0.068 for Spokane, and cardiopulmonary death rate increases of 0.011 to 0.015 in King, and 0.027 to 0.032 in Spokane. Public health interventions are needed to prevent deaths, especially among older adults. Morbidity will likely be reduced by the same measures.

2009-A-356-ISES

Impact Of Wildifres On Exposures To Ambient Ozone And Particulate Matter

I. G. Kavouras, G. Nikolich, D. DuBois, V. Etyemezian; Desert Research Institute, Las Vegas, NV

Wildfires contribute significant amounts of vapors (including greenhouse gases) and particulate matter (PM) into the atmosphere. Biomass burning emissions primarily consist of carbon, water and trace quantities of other elements. Approximately 40% of global particulate organic carbon (OC) and more than 80% of elemental carbon (EC) are originated from wildfires. It is estimated that more than 35-55% of PM2.5 mass is comprised of organic carbon that is primarily dominated by wildfires emissions in western US, Canada and Alaska. A suite of criteria pollutants, carbonaceous aerosol and smoke tracers were monitored in Boise, Idaho. The influence of wildfire smoke was also

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verified by transport modeling and satellite imagery. The factors that affected exposures included local emissions, regional fires, and local air circulation. Regional fires occurred on an episodic basis and were associated with high PM and volatile organic compounds (VOC) levels. The contribution of local emissions (mobile, point and area sources) was more constant and associated with regular activities such as motor vehicle traffic.

2009-A-429-ISES

Effect Of Heat Waves In European Cities

P. Michelozzi,1 D. D'Ippoliti,1 C. Marino,1 F. K. de'Donato,1 K. Katsouyanni,2 K. Katsouyanni,2 A. Analitis,2 B. Menne,3 C. Perucci1; 1Local Health Authority Rome E, Rome, Italy, 2Department of Hygiene, Epidemiology and Medical Statistics, Medical School, Athens University, Athens, Greece, 3Global Change and Health, WHO Regional Office for Europe, Rome, Italy

Background Different studies have estimated the impact of heat waves, however comparisons are difficult given the large variability in the methodological approaches used. Objective A multi-city project funded by the European Union (EuroHEAT) was carried out to evaluate the excess mortality associated to heat waves using an integrated and standardized approach in nine European cities (Athens, Barcelona, Budapest, London, Milan, Munich, Paris, Rome, Valencia) during summers in the study period 1990-2004. Methods Heat-waves were defined using both maximum apparent temperature and minimum temperature and are classified in terms of intensity, duration and timing within summer. GEE models were used to estimate the impact on mortality by gender, age and cause of death. Results were pooled into “Mediterranean” and “North -Continental” cities. Results The greatest impact of heat waves was observed in 2003, especially in Paris (+105%), Milan (+48%), London (+35.7%) and Valencia (+21.4%). In the other years a great heterogeneity in the impact was observed among cities. The risk of mortality was up to 3 times greater for heat waves of long duration and high intensity. A higher susceptibility was observed among females with an increasing effect by age. The impact was greater in Mediterranean cities (+21.8%) than in North-Continental cities (+12.4%), and the strongest association was for respiratory diseases (+52.8% and +20.2% respectively). Conclusions Although heterogeneous, an impact of heat waves on mortality was observed in all European cities considered. During 2003 the highest effect was in cities where heat waves are not typically observed. These results may be explained by the different levels of exposure and susceptibility of the resident population. Public health interventions need to address these aspects in order to prevent a possible additional burden of disease during summer.

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2009-A-426-ISES

Urban Heat Islands And Their Impact On Mortality During Heat Wave Events In Rome, Italy

P. Michelozzi, F. de'Donato, M. Leone, R. Fabrizi, C. Perucci; Local Health Authority Rome E, Rome, Italy

Background High temperatures have an impact on health however, few studies have addressed the heterogeneous impact within urban areas. Urban areas are typically warmer than the surrounding rural areas, this phenomenon is typically known as urban heat island (UHI). The objective of the present study was to define the UHI in Rome using satellite data during summer and assess the spatial variation in the impact of heat on health within the urban area of Rome. Methods Satellite data for the period 2003-2006 were used to define the UHI during summer. The urban area of Rome covers about 300km2 and within this area the spatial resolution of our UHI indicator was of 1km by 1km. Cloud-free days were derived combining satellite data and cloud cover observations. The UHI intensity was calculated as difference between rural and urban values of temperature during the evening. Results The urban heat island phenomenon identified in Rome was similar in all the 60 cloud-free days considered, thus suggesting the robustness of our UHI indicator. The warmest areas were concentrated around the city centre extending to the east of the city, with land surface temperatures LST values on average +2-3°C higher than the rural area. When considering vegetated areas within the city, the UHI indicator accurately discriminated these cooler areas. This indicator was used to analyze the differential impact of heat on mortality during heat waves in Rome the period 2003-2006. Mortality and socio-economic status data, by census tract of residence, are considered to indentify “hotspot areas” which are more at risk during heat waves because of the UHI effect. Results from this analysis can be used in public health to intensify prevention measures in areas most at risk during heat waves.

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Platform

M-PL202: Exposure Modeling

2009-A-444-ISES

A Modeling Framework For Estimation Of Individual Exposure To Air Pollution

L. E. Gerharz, E. J. Pebesma; University of Münster, Institute for Geoinformatics, Münster, Germany

Human exposure to ambient air pollution can differ considerably from stationary measurements in a city and between individuals, depending on their trajectories through time and space. To assess these differences and avoid resource consuming personal measurements, spatially and temporally highly resolved estimations of air quality as well as knowledge about the locations people visit over the day are necessary. Urban regions deserve special interest, due to high intra-urban concentration variability and the large number of people living in those areas. Based on a pilot study in Münster, Germany, we developed a framework to combine modeling techniques for PM10 concentrations with individual positional information to estimate exposure burdens for individuals. To model the spatio-temporal distribution of the PM10 concentration a tiered approach, realized as geospatial web service architecture, is used. The background concentration is estimated by near real-time interpolation of background measurements on a regional scale (5 km x 5 km). Additive to the background, the local distribution of air pollutant emission sources is estimated by a dispersion model (250 m x 250 m) in combination with real-time urban measurements. The contribution of outdoor PM10 concentration to indoor environments is estimated by an indoor mass balance model, using estimated distributions of the parameters. Individual positions are measured by GPS cell phones or trackers, allowing the extraction of information not only of the geographical location but also about transportation mode and characterization of indoor stops. In a case study, weekly GPS profiles sampled in Münster were used to estimate individual exposure to outdoor PM10 retrospectively. As the individual results are subject to large uncertainties, aggregation over time (day, week) is necessary to average parts of these uncertainties out. The individual exposure results show clear differences to the measured ambient concentration and between each other, reflecting individual differences in behavior.

2009-A-432-ISES

Assessing Bisphenol A Internal And Biologically Effective Dose During Infancy

D. Sarigiannis, A. Gotti, S. Karakitsios; JRC, Ispra (VA), Italy

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Bisphenol A (BPA) is used in the manufacture of polycarbonate plastic food contact materials and has been associated with potential effects on human reproduction and neurodevelopment. Newborn infants are known to have significantly reduced metabolic activity (about 5% of the adults), making them vulnerable even at low exposure levels. Thus, an integrated computational platform was developed starting from BPA migration rates from several food contact materials, composing feeding scenarios that include breast feeding and implementing two coupled PBTK models, one for the mother including the expected BPA concentrations in mother’s milk, and one for infants. The PBTK model incorporates all basic concepts of the related models, incorporates BPA glucuronidation and tracks the internal dose of free BPA in the whole body including target organs (e.g. brain and gonads) continuously over time taking into account time-dependent physiologic and biochemical parameters as well as the changes in nutritional needs of humans during infancy. Taking into account the migration from food contact materials and the typical adult feeding scenarios, the concentration in the food, in the blood of the mother and finally in the breast milk was determined. Results show that for the first three months the typical exposure to BPA ranged from 0.1 to 0.5 μg/kg BW/d and the expected plasma concentrations below 0.01 μg/l. Plasma concentrations tend to decrease month by month due to increased enzymatic activity; however, due to the increase of daily intake (0.2 to 13 μg/kg BW/d) linked to the transition from breast feeding to bottle feeding a significant increase is noticed (up to 0.1 μg/l). The mechanistic approach outlined herein is able to link possible changes in food contact materials directly to internal doses throughout infancy and to quantitatively couple biomarkers such as concentration of free BPA in the urine to biologically effective dose and risk assessment.

2009-A-442-ISES

A Two-box Numerical Integration Model Used To Estimate Formaldehyde Exposure From Chamber Emissions Studies

B. D. Landenberger, S. M. Arnold, P. S. Price; The Dow Chemical Company, Midland, MI

Chamber emission studies have been performed on formaldehyde release from paints preserved with a formaldehyde-releasing biocide. These data indicate that formaldehyde is released to the air in a complex emission rate that changes as the paint dries. Emission data must be modeled to give accurate estimates of exposure to a human receptor. In 2008, the United States Environmental Protection Agency (USEPA) Office of Prevention, Pesticides, and Toxic Substances Antimicrobial Division developed a risk assessment for use of a latex paint preserved with a formaldehyde-releasing biocide. The USEPA used their Wall Paint Exposure Model (WPEM) to estimate exposure during indoor painting. Unfortunately, the USEPA’s disclaimer for WPEM states that it is not applicable for chemicals that are “generated” during the curing or drying of paint and thus is not appropriate for this type of assessment. As an alternative, we developed a two-box numerical integration model to estimate formaldehyde exposure concentrations based upon chamber emission studies for paint products. The numerical integration model was

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selected since it allows the model to capture the complex emission rate and the process of paint application over time. In this paper, we present the results of a chamber emission study for one of Dow’s formaldehyde-releasing biocides applied to a series of exposure scenarios. The results of the 2-box model gave a lifetime average daily concentration ranging from 0.072 ug/m3 to 0.20 ug/m3 for the non-professional painter, depending on the scenario, and 13 ug/m3 for the professional painter.

2009-A-499-ISES

The Mismeasure Of Dermal Absorption

J. C. Kissel; U. of Washington, Seattle, WA

Many of the “usual suspects” encountered in risk assessment of commercial chemicals are nonionic, low molecular weight, moderately lipophilic organic compounds. These compounds are well suited to penetrate human skin. Nevertheless, the dermal exposure pathway is frequently dismissed as unimportant when exposures to these compounds are assessed. This outcome is frequently the result of compounded non-conservatism, i.e., the multiplication of an underestimate of dermal potential dose by an underestimate of dermal availability. The assumption that dermal absorption, expressed as fraction of potential dose, is independent of mass loading contributes importantly to underestimation of the latter. Logical application of rudimentary principles of physics, chemistry and mathematics leads to the conclusion that this assumption is not well founded. Empirical evidence from in vivo and in vitro absorption studies, transfer studies, and human exposure studies in which environmental and biomonitoring data are adequate to permit mass balance provide additional support for the view that the dermal availability of many compounds of interest is dependent upon mass loading on the skin. To aid understanding of underlying phenomena, a dimensionless dermal number is proposed representing surface area normalized delivery rate divided by potential absorptive flux. Application of this tool to some commonly cited experimental results involving pesticides reveals that low fractional absorption is expected under flux-limited conditions, but that high fractional absorption should be expected under delivery-limited conditions and that delivery-limited conditions are very likely to be encountered in many exposure scenarios of interest.

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Poster

M-P001a: Monday: Exposure, Risk, Epidemiology - Theme: Environmental Epidemiology, Tracking, and Linkages

2009-A-337-ISES

Association Between Exposure To Organochlorines And The Occurrence Of Atopic Dermatitis In Japanese Infant

H. Fukata,1 S. Suzuki,2 N. Shimojo,1 Y. Kono,1 C. Mori1; 1Chiba University, Chiba, Japan, 2Shimoshizu National Hospital, Yotsukaido, Japan

To investigate association between exposure to organochlorines and an allergy disease in the infant, we collected 210 umbilical cords in Chiba City (Japan), and we did questionary survey on atopic dermatitis (AD) at 7-months old. We measured concentrations of organochlorines (polychlorinated biphenyls [PCBs], β-hexachlorocyclohexane [HCH], p,p'-DDTs, p,p'-DDE, nonachlor, oxychlordane, hexachlorobenzene [HCB], mirex) and heavy metals (Hg, Cd, Pb) in the 105 cases. There is no association between atopic dermatitis and heavy metal concentrations. On the other hand, PCB concentrations on AD group (n=30) are 68±46 pg/g-wet weight (mean±S.D.), non-AD group (n=58) 57±31 pg/g-wet weight, HCH concentrations are 108±117 pg/g-wet weight and 62±42 pg/g-wet weight, respectively. Odds ratio are significant at 120 pg/g-wet weight for PCBs and 40 pg/g-wet weight for HCH, respectively. Although these results are led by a few samples, our present data indicated an association between exposure to organochlorines and the occurrence of AD in Japanese infants. It is not unclear that the association is due to combine effects of chemicals and is due to fetal exposure or breast milk exposure. This study was approved by the “Congress of Medical Bioethics” of Chiba University and University of Yamanashi, and all the samples were obtained after receipt of written informed consent.

2009-A-313-ISES

The Relation Of Steroid Hormone And Gender Role Behavior To Prenatal And Postnatal Exposure To Phthalates In Pre-school Children

H. Y. Ku,1 P. H. Su,2 P. C. Liao,3 H. L. Huang,4 J. Angerer,5 S. L. Wang1; 1Division of Environmental Health & Occupational Medicine, National Health Research Institutes, Miaoli, Taiwan, 2The Department of Pediatrics, Chung Shan Medical University, Taichung, Taiwan, 3Department of Environmental and Occupational Health, Medical College National Cheng Kung University, Tainan, Taiwan, 4Department of Psychology, Kaohsiung Medical University, Kaohsiung, Taiwan, 5Institute and Outpatient Clinic of

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Occupational, Social and Environmental Medicine, Friedrich-Alexander University, Erlangen, Germany

Phthalates exposure was found associated with decreased anogenital index in male newborns. It is hypothesized that male sex hormone might be altered and gender role behavior changed according to phthalates exposure. We assess the relation of steroid hormones and Pre-School Activities Inventory (PSAI) at 5 years to phthalate exposure at 0, 2, 5 years in a birth cohort established in 2001 and followed till 2006 in central Taiwan. Eleven phthalate monoester metabolites representing the exposure to five commonly used phthalates (DEHP, DiBP, DnBP, BBzP, DiNP) were measured in maternal and children’s urine by LC-MS/MS. Urinary phthalate metabolites were associated with decreased serum testosterone concentrations at the age of 2-3, and 5-6 years, with more significant correlation in girls at 2 and 5 years (ie:2-3 year girls : DEHP metabolites r= -0.59~-0.66, p<0.05 , MiBP r=-0.65 p<0.05; 5-6 year girls: MBzP r=-0.49, p<0.001). Maternal exposure to phthalates was correlated with decreased maternal estrogen (5oxo-MEHP: r=-0.39, p<0.05) in those who gave birth to male baby, and increased estrogen in those who gave birth to female baby (5oxo-MEHP: r=0.29 p<0.05). Maternal testosterone was positively correlated with PSAI score in boys (Pearson correlation coefficient=0.25, p value<0.10 ), and maternal estrogen was negatively correlated with PSAI score for girls(r=-0.22, p value=0.10). In addition, urinary MiBP, MBzP and DiNP metabolites were positively correlated with PSAI score in 5-6 year old boys, after adjusting for potential confounders. In 5 year old girls, there was a significant negative correlation between urinary MnBP, MiBP and MBzP and PSAI scores.It is firstly reported that testosterone levels decreased with increasing phthalates exposure consistently in young children. Maternal steroid hormone may associate with gender role behavior in children at the age of 5 years. Postnatal exposure to MnBP, MiBP and MBzP in girls was associated with increased feminine-typical characteristics.

2009-A-261-ISES

Correlation Between The Level Of Dioxins And The Level Of Indicators (Total-cholesterol, Triglyceride And Hba1c) Of Diabetes And Hyperlipoproteinemia In Japanease Adault

Y. Mochida, H. Fukata, Y. Matsuno, K. Sakurai, C. Mori; Chiba University, Chiba, Japan

Correlation between the level of dioxins and the level of indicators (total-cholesterol, triglyceride and HbA1c) of diabetes and hyperlipoproteinemia in Japanease adault. Yoji MOCHIDA1, Hideki FUKATA2, Yoshiharu MATSUNO3, , Kenichi Sakurai4, , Chisato MORI1,2,3, 1Dept of Bioenvironmental Med,Grad Sch of Med,Chiba Univ.,Japan. 2Center for Preventive Medical Science,Chiba Univ. 3Center Environ Health Field Sci,Chiba Univ. 4Clinical Cell Biology Grad Sch of Med,Chiba Univ. Purpose: Hyperlipidemia and diabetes have been implicated as risk factors for metabolic

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syndromes (MS). The association of persistent organic pollutants(POPs) with MS is also reported in previous cohort studies. We investigated the relevant data of biochemical examinations to find the association between MS and blood concentration of dioxins. Method: The samples we have collected during the period from 2006 through 2008 were retrospectively compared between the total dioxins (polychloro-dibenzo-p-dioxin PCDD, polychloro-dibenzofran PCDF and coplanar polychlorinated benzen Co-PCB) level and the levels of total-cholesterol (TC) , triglycerid (TG), and HbA1c. Result: 81 subjects aged 46.4 on average were at the total dioxin level of 0.094pg-TEQ/g wet-weight on average, whereas all the subjects were at the total dioxin level of < 0.05pg-TEQ/g wet-weight, with TC ≥ 220 (odds ratio, 13.5 95 percent confidence interval, 2.9 to 62.5), and HbA1c ≥ 5.8% (odds ratio, 4.12 95 percent confidence interval, 1.16 to 14.62). Conclusion: The total dioxins level is associated with the levels of TC, TG, and HbA1c, suggesting that dioxins and/or other POPs may be one of the risk factors for metabolic syndromes including hyperlipidemia and diabetes.

2009-A-269-ISES

Content Of Organochlorine Pesticides In Breast Milk Of Rural Women From Ararat Valley, Armenia

A. Tadevosyan,1 A. Tadevosyan2; 1Yerevan S|tate Medical University, Yerevan, Armenia, 2Yerevan State Medical University, Yerevan, Armenia

Content of Organochlorine Pesticides in Breast Milk of Rural Women from Ararat Valley, Armenia Artashes Tadevosyan1, Natalya Tadevosyan1, Zemphira Navasardyan2, Mary Samsonyan2 1Yerevan State Medical University, 2Artashat Medical Center, Armenia In previous study we evaluated OCP exposure and the possible relationship with adverse birth outcomes by analyzing breast milk samples of rural women from pre-mountainous Armenia. We enlarged the scope and studied OCP content in breast milk of rural women from Ararat valley, region with the most intensive use of pesticides. 30 samples were randomly collected during the first 2-3 days after delivery from a subset of women in the maternity department of the Artashat Medical Center. Residues of lindane and DDT (and its metabolites DDD and DDE) were measured using gas chromatography. DDE was detected in all samples and γ-HCH in 96.7% of samples. Mean concentration of γ-HCH was 0.00329±0.00089 mg/l, DDE - 0.0130±0.0026 mg/l; sum of pesticides made 0.022412±0.0083 mg/l. There were not statistically significant differences in OCP content in primaparous and multiparous women’s milk. Almost 67% of women experienced several complications of pregnancy and labor, including toxicosis, preterm or obstructed labor, history of miscarriages. Statistically not significant increase of OCP’s concentration in the group of women with complications of labor was detected (0.020206 mg/l vs. 0.012694 mg/l). We compared these findings with data from pre-mountainous region of Armenia. The concentration of OCP’s in breast milk of women from Ararat valley was significantly higher and made 0.022412±0.0083mg/l versus 0.005425±0.0013 mg/l (p<0.0001) with frequency of detection 100% versus 80% correspondingly.

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In a pooled sample of women from both regions the frequency of complications of pregnancy and labor were analyzed. The top and bottom quartiles of OPC’s concentrations were compared. High level of exposure to OPC’s was associated with high risk of complications: OR=6.00; 95% confidence interval 1.30, 31.52.

2009-A-402-ISES

HFE H63D Polymorphism, Accumulative Lead Exposure and Blood Pressure: A Gene-Environment Interaction

A. Zhang,1 S. Park,1 R. Wright,2 B. Mukherjee,1 D. Sparrow,3 P. S. Vokonas,4 H. Nie,2 H. Hu1; 1University of Michigan, Ann Abor, MI, 2Harvard University, Boston, MA, 3Harvard University and Veterans Affairs Boston Healthcare System, Boston, MA, 4Veterans Affairs Boston Healthcare System, Boston, MA

Background and Objective: Environmental lead exposure and one of the hemochromatosis (HFE) gene mutations, H63D, have been associated with an increased risk of hypertension. However, it is unclear whether the HFE H63D mutation modifies the association of accumulative lead burden with blood pressure. The present study assessed effect modification of bone lead by the H63D mutation in association with blood pressure in community-dwelling older men. Methods: We examined 695 participants with a total of 1585 observations of systolic (SBP) and diastolic (DBP) blood pressure (median SBP=135 mm Hg and DBP=81 mm Hg) in the Normative Aging Study between 1991 -2002. We used K-x-ray fluorescence for bone lead measurements, standard mercury sphygmomanometer for systolic and diastolic blood pressure measurements, multiplex PCR for HFE genotyping, and linear mixed effects regression models with a random intercept adjusted for covariates of interest. Results: Of 695 subjects, 93 (13.4%) and 169 (24.3%) carried the HFE H63D and C282Y variants, respectively. After adjusting for age, race, body mass index, waist circumference, family history of hypertension, education, alcohol consumption, cigarette smoking, heart rate, fasting glucose, and calcium intake, bone lead levels measured at the first visit were associated with steeper increases in SBP in men with at least one H63D allele (p-values for interaction = 0.02 for tibia and <0.01 for patella), compared with men with either the wild-type allele or C282Y allele. Among H63D variants, interquartile range increases in lead levels in tibia (13 μg/g) and patella (19 μg/g) were associated with 3.72 mm Hg (95% confidence interval (CI), 0.59-6.84 mm Hg) and 4.16 mm Hg (95% CI, 1.12-7.20 mm Hg) increases in SBP, respectively. No effect modification in relation to DBP was found. Conclusion: The HFE H63D polymorphism, but not the C282Y mutation, enhances susceptibility to the deleterious impact of cumulative lead exposure on SBP.

2009-A-491-ISES

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Exposure Assessment To Chlorination By-products In A Case-control Study On Reproductive Outcomes

P. Levallois,1 S. Gingras,1 C. Legeay,2 C. Catto,3 G. Charest-Tardif,3 M. Rodriguez,2 R. Tardif,4 S. Marcoux2; 1INSPQ-CHUQ, Quebec, QC, Canada, 2Université Laval, Quebec, QC, Canada, 3Université de Montréal, Montréal, QC, Canada, 4Université Montréal, Montréal, QC, Canada

The objective of the study is to compare different methods of exposure assessment to Trihalomethanes (THM) in a case-control study of intrauterine growth retardation (IUGR). This study was conducted in the Québec metropolitan area (Canada) from August 2006 to April 2008. This preliminary analysis was conducted on 264 cases and 875 controls. Nine water distribution systems supplied by surface water were involved. The monitoring of THM was conducted every month on 45 sampling locations in order to estimate monthly variations in residence’s tapwater. A phone interview on lifestyle habits during pregnancy was completed within three months after the birth. Exposure of our subjects to Total THM (TTHM) and chloroform (CHCl3) during the last trimester of pregnancy was estimated according to the following assessment methods: a) annual average of TTHM from regulatory monitoring data; b) estimated concentrations of Chlorination By-Products at the tap of the home of each participant based on the intensive monitoring conducted in that study; c) estimated CHCl3 uptake via ingestion of considering bottled water and tapwater consumption as well as the use of point-of-use device and boiling water for hot beverages. The range of TTHM concentrations in residences’s tapwater estimated with the b) method was 10.5-249.9 µg/l with a median of 42.4 µg/l. The Spearman correlation between a) and b) estimates for TTHM was 0.103 (p<0.001). When considering c) values for chloroform, no correlation was found either with concentrations estimated from a) or b): Spearman correlation between a) and c) values of 0,020 (p=0,505). The possible impact of such measurement errors of THM exposure on the Odds ratios of IUGR will be discussed. This study is funded by the Canadian Institutes of Health Research (CIHR).

2009-A-386-ISES

Associations of Cadmium and Lead with Hearing Loss: A Sample of the U.S. General Population

Y. Choi,1 H. Hu,1 B. Mukherjee,2 J. Miller,3 S. Park1; 1Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, 2Department of Biostatistics, University of Michigan School of Public Health, Ann Arbor, MI, 3Department of Otolaryngology, University of Michigan School of Medicines, Ann Arbor, MI

Background: Cadmium and lead are well-known ototoxic heavy metals because of their ability to generate reactive oxygen species which may cause apoptosis in auditory nerve cells. The deleterious effects in the auditory system from these metals have been well

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documented in several animal experiments. Few epidemiologic studies of hearing dysfunction have been reported in human populations, however. We investigated the impact of cadmium and lead exposures on hearing impairment in the U.S. general population while controlling for potential confounding effects of noise exposure and other major factors contributing to hearing impairment. Materials and Methods: We examined 4,271 adults of 20 to 69 years of age from the National Health and Nutrition Examination Survey (NHANES) 1999-2004, a representative sample of the U.S. general population. Pure-tone air conduction hearing thresholds were measured at frequencies of 0.5 to 8 kHz and pure-tone averages at the speech (0.5, 1, 2 and 4 kHz) or high frequencies (3, 4 and 6 kHz) were computed. Blood cadmium and lead levels were measured using atomic absorption spectrometer. Loud noise exposures from current job, recreation and firearm were collected through intensive questionnaires. Linear regression models with both quintiles of blood cadmium and lead were fit with adjustment for potential confounding factors. Results and Discussion: Subjects in the highest quintile of cadmium had pure-tone average thresholds at speech frequencies of 1.54 dB higher than subjects in the lowest quintile of cadmium (p-value = 0.048). The pure-tone average thresholds at speech frequencies in the highest quintile of lead were 1.56 dB higher than those in the lowest quintile of lead (p-value = 0.022). Our findings suggest that cadmium and lead levels to which current general US adults are exposed may lead to hearing loss and that reducing those exposures may delay age-related hearing loss.

2009-A-445-ISES

Cumulative Community Asbestos Exposure From Vermiculite Processing And Pleural Abnormalities In Minneapolis

K. K. Raleigh,1 B. H. Alexander,1 J. H. Mandel,1 J. L. Adgate,1 G. Ramachandran,1 S. Cho,1 J. Johnson,2 R. B. Messing,2 A. N. Williams2; 1University of Minnesota, School of Public Health, Division of Environmental Health Sciences, Minneapolis, MN, 2Minnesota Department of Health, St. Paul, MN

Background: Vermiculite ore from Libby Montana was processed at the Western Mineral Products/W.R Grace plant in a densely populated neighborhood in Minneapolis, MN from 1936-1989. Waste rock made available to the community was used in yards, gardens and driveways, resulting in residential exposure for children and adults. Methods: Non-occupational asbestos exposure was estimated for 2,222 current and former residents. Air dispersion modeling was used to estimate background exposures (fiber/cc*month) for each individual. Additional exposures were estimated using frequency of self-reported exposure-related activities. Monte Carlo simulation was used to develop total fiber exposure profiles for all individuals by summing background and scenario-based exposures. We recruited 461 individuals for clinical evaluations, including a pulmonary function test and a chest x-ray evaluated by two NIOSH certified

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B-reading radiologists. We evaluated the prevalence of any pleural abnormalities by cumulative asbestos exposure estimates. Prevalence odds ratios for pleural abnormalities by quartile of cumulative asbestos exposure were estimated with multiple logistic regression; adjusting for age, sex and history of jobs with potential asbestos exposure. Results: Based on estimates, the community experienced a wide range of environmental asbestos exposure through individual contact from moving or using vermiculite waste rock, playing on waste piles, or installing insulation. Median exposure (range) for all participants and those with chest x-rays was 0.0347 (3.88x10-6-15.98) and 0.0503 (3.88x10-6-15.98) fiber/cc*months respectively. Compared to those in the lowest exposure quartile, the highest quartile had an elevated risk of any pleural abnormality OR=3.16 (95% CI: 1.36, 7.36). Risks for the second and third quartiles were modestly elevated; OR= 2.12 (95% CI: 0.89, 5.04) and 1.51 (95% CI: 0.62, 3.65) respectively. Conclusion: These preliminary findings indicate an association between cumulative community exposure to asbestos from processing contaminated vermiculite with measurable lung changes on chest x-rays.

2009-A-399-ISES

Influence Of Regional Landscape- Geochemical Conditions On Children Prevalence After Chernobyl Accident

M. V. Naboka; Radioecological Center, Kiev, Ukraine

Influence of regional landscape- geochemical conditions on children prevalence after Chernobyl accident M.Naboka, V.Shestopalov, A.Lichosherstov (Radioecological Center of National Academy of Sciences of the Ukraine) W.Karmaus (University of South Carolina) It is known that transition factors of 137Cs in first link of food chain from soil to plant can vary 2-7 times in area with the same level of the soil contamination. Accordingly different levels of the accumulation 137Cs can be found in food and respective humans. However, yet no relationship morbidity-exposure association of the local population has been found. Our goal was to study the relationship between growth of non-cancer morbidity of children residing in contaminated (137Cs 8-383 kBq/m2) regions, with landscape- geochemical condition, that may facilitate migration of 137Cs in first link of food chain (soil to plant). The results of a retrospective (1988-2007) analysis comparing the prevalence of the digestive system diseases after Chernobyl accident showed that the occurrence of morbidity relates to time and level of radioactive contaminations in regions contaminated above 100 kBq/m2. After 10 years of exposure the prevalence ratio (PR) was more than 2 times higher in region contaminated above 300 kBk\m2 and in 1.3 times higher in region with soil levels above 100 kBk/m2. Within a 20-year observation period, we determined an interaction of time and 137Cs exposure on the prevalence of digestive system diseases.

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Our results suggest that regional landscape-geochemical conditions, which facilitated migration of 137Cs in first link of food chain from soil to plant in regions with contamination levels above 100 kBk/m2 , led to stronger association of the 137Cs on the digestive system. The results indicate the necessity to take regional landscape-geochemical conditions into account and to conduct an ecological risk assessment.

2009-A-510-ISES

Air Pollution And Adverse Birth Outcomes In Southern California - Effect Estimates Based On Four Exposure Assessment Methods

J. Wu,1 M. Wilhelm,2 B. Ritz,2 J. H. Chung1; 1University of California, Irvine, CA, 2University of California, Los Angeles, CA

Background: A large number of studies have associated traffic-related air pollution exposure with adverse birth outcomes. However, few studies have systematically examined differences in effect estimates due to different exposure assessment methods. Objectives: We aimed to compare the associations of maternal residential exposure to traffic-related air pollutants and adverse birth outcomes (preeclampsia, preterm delivery, and term low birth weight) based on four commonly-used exposure assessment methods. Methods: We collected 89,640 singleton birth records from a four-hospital network during 1997-2006 in Los Angeles County and Orange County, California. Residential addresses at birth were geocoded using the Tele Atlas geocoding service. Maternal exposures to nitrogen oxides were estimated for each mother using measurement data from monitoring stations, CALINE4 line-source dispersion model, and land-use regression model. Traffic density was also estimated as a surrogate for traffic-generated air pollution. Logistic regression models were used for effect estimates, adjusting for maternal age and race, parity, prenatal health care, poverty, conception season, diabetes (for preeclampsia), pyelonephritis (for preterm birth), and weight gain (for term low birth weight). Windows of vulnerability by pregnancy period were also investigated. Results: The highest risk of preterm birth was observed using exposure estimates based on air monitoring station data. The highest risk for preeclampsia was observed using exposure estimates based on the CALINE4 model and the air quality station data (results were similar using the two approaches). We only observed a significant association of exposure with term low birth weight for traffic density estimates. Land-use regression models were found to be not superior to the other methods, possibly because we may have inappropriately seasonalized the exposure estimates from land-use regression models. Conclusion: Effect estimates for birth outcomes vary by different exposure assessment methods.

2009-A-264-ISES

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Exposure To Highway Traffic Exhaust And Its Impact On Childhood Respiratory Health In Alpine Valleys In Switzerland

R. Ducret-Stich, M. Ragettli, C. Braun-Fahrländer, A. Ineichen, H. C. Phuleria, C. Schindler, L. J. S. Liu; University of Basel, Basel, Switzerland

Trans-Alpine highway traffic exhaust is the major source of air pollution along the Alpine highway valleys. However, little is known about residential exposure and its impact on respiratory health. We conduct a pediatric asthma panel study supplemented by a cross-sectional questionnaire survey to examine highway exhaust exposure and its health effects among. Between 2007 and 2008, 2’305 schoolchildren (ages 7-14) from the Swiss Alpine communities participated in a questionnaire survey on respiratory health. A subset of 13 children with asthma participate in monthly monitoring of home outdoor NO2 and PM, and respiratory health indicators including exhaled NO and oxidative stress markers in exhaled breath condensate over 18 months. Concurrent measurements of PM10, PM1, particle number concentrations (PN), and NOx are taken at 6 fixed and mobile locations, which are used with various GIS parameters to model home outdoor exposures. Model predictions are validated with the home outdoor measurements. Source apportionment results are used to assess the influence of truck exhaust on respiratory health. Annual means of pollutants varied between 13-21ppb (NO2), 11-36ppb (NO), 17-34µg/m3 (PM10), 11-15µg/m3 (PM1), and 10’000-20’000 particles/cm3 (PN). Higher levels of NOx were observed close to the highway and dropped to background levels after 60-100m. Results of the logistic regression from the questionnaire survey showed significant associations between PM10 from trucks and wheezing (OR=1.24, 95% CI: 1.01-1.52) or hay fever (OR=1.26, 95% CI: 1.05-1.52), and between PM10 from cars and wheezing (OR=1.30, 95% CI: 1.02-1.67). We demonstrate that modeled PM emitted from the trans-Alpine highway traffic, especially from trucks, is a significant risk factor for adverse respiratory effects in school children. The modeled pollution exposures will be validated by the home outdoor measurements and the source apportionment results.

2009-A-314-ISES

Analysis Of Extreme Weather Event And Damage From Climate Change In Korea

J. Jae-Yeon; Department of Preventive Medicine, Ajou University, Suwon, Republic of Korea

Analysis of Extreme Weather Event and Damage from Climate Change in Korea Jae-Yeon Jang, Soo-Nam Jo, Sun-Ja Kim, Si-Heon Kim Department of Preventive Medicine, Ajou University Introduction Global warming has increased frequency and intensity of extreme weather events. We analyzed extreme weather events in Korea that trends and assess changes to the frequency, intensity and damage. Methods

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We analyzed data of daily temperature, precipitation and humidity . The areas investigated were six major cities(Seoul, Busan, Daegu, Daejeon, Incheon, Gwangju) and Gangreung on the coast. We resorted extreme weather events and categorized into flood, typhoon, storm, snow and others. We analyzed in terms of annual frequency, average duration of extreme weather events and their damages deaths, sufferers and property (1981-2006). Results The mean temperature increased from 12.35°C to 13.79°C between 1971 and 2007. It was the greatest increase in winter(Dec to Feb), which was followed by summer(Jun to Aug), spring(Mar to May) and fall(Sep to Nov). Precipitation made about 21% increase from monthly average of 100.5mm to 121.7mm. The increase was mostly attributed to the increased rainfall during summer with rainfall decreasing in fall, winter, and spring. The frequency of extreme weather events tended to rise until the 1980s and started to go down in the 1990s. But the average duration of a event continued to rise rapidity since 2000. As a result, while the total number of the deaths and sufferers decreased, the mean deaths and sufferers per event were on the rise. As for property damage, 62% of the top 20 major event in recent history of Korea took place in 2001~2006. Discussion In Korea, the frequency of extreme weather events has taken a downturn, but once it happens, its size and damage commands such volume. Therefore, the total damage size by extreme weather events have continued to grow.

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Poster

M-P001b: Monday: Exposure, Risk, Epidemiology - Theme: Air Exposures

2009-A-350-ISES

Measuring In-vehicle Particulate Organic Species And Acute Cardiorespiratory Response In The Atlanta Commuters Exposures Study

J. A. Sarnat,1 R. Greenwald,1 M. H. Bergin,2 C. Boswell,2 F. Yip,3 T. Boehmer3; 1Emory University, Atlanta, GA, 2Georgia Institute of Technology, Atlanta, GA, 3Centers for Disease Control and Prevention, Atlanta, GA

Numerous studies have indicated that specific sub-populations may be at greater risk for PM2.5-mediated health effects due to their proximity and/or enhanced exposures to traffic-related pollution. Moreover, even short durations inside vehicles have been shown to contribute substantially to total daily pollutant exposures. It is plausible that daily commuters comprise a susceptible sub-group to traffic pollution-related health effects. To address these concerns, we are currently measuring in-vehicle pollutant concentrations and corresponding biomarkers of acute cardiorespiratory response for 40 older adults, as part of the Atlanta Commuters Exposures (ACE) Study. One novel component of this study is the ability to assess short-term (2 hour), integrated speciated particulate organic concentrations during the commutes. There is emerging evidence that that this particle fraction may be related to adverse cellular outcomes, including mitochondrial dysfunction. We have developed a novel in-vehicle sampling manifold that will provide robust measurements of particulate organic mass over typical commuting durations. Size-resolved PM mass is measured gravimetrically from filter samples collected using a 4-stage Harvard Compact Cascade Impactor. The mass concentration of particle-phase organic species is determined by Thermal-Optical Transmittance analysis of 25 mm quartz filters sampled at 20 l/min yielding approximately 24 µg of organic mass. The speciation of organic compounds is performed using Thermal Desorption/Gas Chromatography Mass Spectrometry from 25 mm quartz filters sampled at 30 l/min yielding approximately 36 µg of total organic mass. Preliminary findings from eight in-vehicle measurements in Atlanta showed elevated n- and cyclic alkane levels (heptadecyl- and octadecyl-cyclohexane concentration range: 10,000 - 20,000 pg/m3), petroleum biomarkers (17B(H)-21A(H)-30-Norhopane mean = 750 pg/m3); and specific polycyclic aromatic hydrocarbons, phenanthrene and fluoranthene, (mean = 660 and 520 pg/m3, respectively). Detailed results examining sampler performance and in-vehicle organic concentrations, as well as associations between these species and inflammation biomarkers (i.e., exhaled nitric oxide) will also be presented.

2009-A-290-ISES

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Potential Nanotoxicity Health Risks From Domestic Indoor Solid Fuel Burning Using The “Basa Njengo Magogo” Technique

C. Wright, P. Forbes, R. Oosthuizen; CSIR, Pretoria, South Africa

In South Africa, indoor solid fuels are used by 3.2 million (24% of total population) and 2.3 million households (17%) for space heating and cooking purposes, respectively, especially in low income areas. Personal exposure to emissions from burning coal or wood may increase risk for chronic obstructive pulmonary disease, lung cancer and tuberculosis. Emissions include particulate matter, where the smaller the particle size, the more statistically significant the association with adverse human health effects. Studies specific to unintentionally formed nanoparticles (<0.1μm) such as those from combustion processes suggest that these particles are more toxic than larger particles and may cross the blood-brain barrier and placenta. A study is underway to accurately quantify particulate emissions, including particle size characterisation, from domestic solid fuel burning. Potential nanotoxicological health risks will be assessed from exposure to emissions from the government supported “Basa njengo Magogo” (BnM) method of lighting a fire. This technology is derived from the “upside-down” or “Scots” method and approximately 66% of recently surveyed households use this technique. Preliminary findings showed that when compared with other methods under controlled laboratory conditions, total particulate emissions were up to 27% less than from bottom-up fires, while the BnM boiled water the quickest and the solid fuel to weight ratio was reduced. Here, initial results for size characterisation tests will be presented and discussed in relation to potential nanotoxicological health risks.

2009-A-469-ISES

Assessment Of School Children’s Exposure To Traffic Exhaust At Various Outdoor Environments In The Seattle Area Using Outdoor And Biological Measurements

M. Tsai; University of Basel, Basel, Switzerland

School children riding diesel school buses may be exposed to significant levels of diesel emissions (DE). This study characterizes and models the exposure of children to DE and general traffic exhaust by sampling for NO2, PM2.5, black carbon (BC), 1-nitropyrene (1-NP), and urinary samples for markers of diesel exposure metabolites and biomarkers of inflammation and oxidative stress. The sampling locations, selected based on surrounding traffic conditions (highways, arterial roads, residential roads), included roadside sites near schools, near homes, in school playgrounds, and on school buses. NO2 levels were measured with the Ogawa passive samplers over 2 weeks at 11 locations monthly, while extensive seasonal NO2 samples were collected at 78 locations over 2 weeks in 3 seasons. PM2.5, 1-NP, and BC were measured using Harvard Impactors at 26 home outdoor locations (10 concurrent) over two-week periods during heating and non-heating seasons. Urinary samples were collected from 107 children over the heating and non-heating seasons. Collocated sampling with instruments at a regulatory air monitoring station

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allows us to control for temporal variation. PM2.5 concentrations averaged 7.5±2.2 ug/m3 (range: 3.3 - 12.9), BC levels averaged 0.6±0.2 ug/m3 (range: 0.2 - 1.1), NO2 levels averaged 11.8 ppb (range: 3.5 to 22.3), while 1-NP averaged 0.3±0.3 pg/m3. Geographic and seasonal differences were observed; for instance, overall NO2 concentrations were 9.8±5.1 ppb (near homes) and 13.5±5.2 ppb (school playgrounds); and residential PM2.5 levels were 9.2±1.7 ug/m3 (heating) and 5.9±1.7 ug/m3 (non-heating). PM2.5 and NO2 on the bus averaged 20.3±14.2 ug/m3 and 20.0±7.8 ppb, respectively. Using these sampling data and GIS data, regression models are constructed to estimate the spatial distribution of NO2, PM2.5, and 1-NP in the Seattle area. These estimates are compared with DE markers from the urinary samples to determine the associations between outdoor exposures and the total body burden of these pollutants.

2009-A-439-ISES

Estimating Air Pollution Exposure For Epidemiological Studies In Developing Countries - An Example From Nigeria

A. B. Mustapha, D. J. Briggs, A. L. Hansell; Imperial College London, London, United Kingdom

Background In Nigeria, the government is faced with developmental challenges. Electricity supply to most of the country is poor and there is a lack of environmental monitoring stations. This study discusses how multiple exposure metrics were synthesized to characterise geographical exposure in Warri, Niger Delta region. Methods A cross-sectional questionnaire completed by 1,397 school children in 17 schools assessed self-reported exposure. Traffic counts were taken outside schools and distance of schools to major streets was measured. Measurements of particulate matter and CO were made in schools and in outdoor residential background locations using portable monitors. Associations between various exposures measures were estimated in a linear regression and correlation analyses. Classification of schools in terms of their air pollution characteristics was done using cluster analysis of the raw measures of environmental pollution and using compound factors constructed using principal components analysis. Results Many of the measured pollution variables and self-reported exposure measures were correlated. The mean (and SD) CO concentration for schools with >90% of children reported traffic disturbance was 9.92 (9.3) ppm and for the remaining schools was 1.2 (1.6) ppm. Coarse and intermediate particles dominated the PM fraction in all schools. Cluster analyses using two different approaches indicated that schools in the north and rural-schools were the least polluted, while schools in the south were more polluted with main sources being cars and motorcycles. Field measurements using portable monitors were limited due to problems with electricity supply, humidity and security concerns. Conclusion

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Use of multiple methods to assess and cross-validate exposure complimented limited representativeness and potential mis-classification in the single exposure measures and may be useful in areas where possibilities for direct measurement is limited. The exposure measures used may thus give relatively robust indicators of exposure to pollutants mix from main sources in the study area.

2009-A-360-ISES

Change Of Chemical Property And Released Inflammatory Mediators By Urban Air Particles During The Asian Dust (yellow Sand) Period In Korea.

D. Shin, J. Yang, Y. Lim, J. Jang, J. Kim; Yonsei University, Seoul, Republic of Korea

The Asian dust storms appear annually and blow across most of Korea and can even reach Japan. The Asian dust storm travels from the China’s Gobi Desert through some of China’s biggest industrial centers, picking up pollutants such as PAHs and metals on the way. We study to analyze the chemical composition and to evaluate the cell toxicity of ambient PM10 and PM2.5 in Asian dust storm. The contribution ratios of hazardous metals (such as Fe, Zn, Mg, Mn) of the fine particle matter were much more than that in non-dust storm days. The dust storm PM significantly decreased the cell viability and increased the pro-inflammatory cytokine levels at low dosage. Its toxic effects might be attributed to oxidative damage mediated by pro-oxidant/antioxidant imbalance or excess free radicals.

2009-A-425-ISES

Development Of Self-check Software On The Website To Prevent Sick Building Syndrome

H. Nakaoka,1 E. Todaka,1 M. Hanazato,2 C. Mori3; 1Center for Environment, Health and Field Sciences, Chiba University, Kashiwa, Chiba, Japan, 2Department of Architecture, Graduate School of Engineering, Chiba University, Chiba, Japan, 3Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University, Chiba, Japan

“Sick Building Syndrome (SBS)” is a series of symptoms such as headache, eye irritation, throat ache, caused in newly built or remodeled houses and office buildings. The major causes of SBS are suspected to be volatile organic compounds (VOCs) indoor air. To solve this problem fundamentally it is necessary to apply the strategic preventive medicine. There are three steps to prevent SBS as in the preventive medicine. First, recognition of SBS, second, screen people to find sensitive (high risk) group, and third, encourage them to take action to prevent SBS. As the first step to prevent SBS, we built a model town called “Chemiless Town” in the university campus in which building and houses were built with fewer chemicals. There is a gallery in the town to spread the

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knowledge about SBS. As the second step, we developed a software of self-check on the website to screen sensitive people to chemicals. This software is called “Chemiless Necessity Test” and has been uploaded since April, 2009. Anyone who accesses the website can know their sensitivity to the chemicals by answering the questions. After knowing the sensitivity, they are asked more questions if they think to become careful in daily life not to be exposed to chemicals to prevent SBS. The results showed that the percentage of high-risk group was 70% and low-risk group was 29% respectively. Though we need more number of subjects and follow up their action, our present results suggest that more than 80 % of people who know his/her sensitivity to chemicals think that they will become more careful to chemical exposure. It means that recognition is important to take actions to prevent SBS. By using this new software, the number of people who will suffer from SBS is expected to decrease.

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Poster

M-P001c: Monday: Exposure, Risk, Epidemiology - Theme: Developing Exposure Science

2009-A-332-ISES

Application Of Exposure Science To Epidemiologic Issues Related To Setting Standards For Criteria Air Pollutants

W. E. Wilson, J. Pinto; Environmental Protection Agency, Research Triangle Park, NC

As staff at the National Center for Environmental Assessment review the information relevant to setting national ambient air quality standards for criteria pollutants, they become aware of data gaps and research needs. Epidemiologic studies observe regional heterogeneity of the relative risk of mortality per unit increase in particulate matter, higher in the northeastern and central US, but lower in the West and South. Exposure Science can provide insight into the possible causes of this heterogeneity by addressing the following questions. To what extent is the heterogeneity in calculated risk due to the more uneven spatial distribution of exposure in the larger counties of the western US; differences in infiltration rates due to differences in climate and housing stock; differences in the volatility of the atmospheric PM; or differences in toxicity due to regional differences in pollution composition? Are seasonal differences due to seasonal differences in infiltration rates or pollution composition? In the near future, EPA must reconsider the annual level for the PM2.5 standard and decide what protection is needed from PM10-2.5 (thoracic coarse particles) and ultrafine particles. Analytical techniques need to be developed for measuring personal exposure to PM10-2.5 and ultrafine particles. Techniques exist for estimating the ambient component of personal exposure to PM2.5 and should be used in exposure and epidemiologic panel studies. Analytical techniques also need to be developed for similar studies of ambient thoracic coarse and ultrafine particles; and for estimating exposure to indoor-generated pollutants and exposure to outdoor pollutants that are not measured at the central monitoring site. A continuing effort is needed on techniques for estimating personal exposures based on empirical models and for estimating exposure gradients near sources (e.g., exposure to traffic- generated pollutants. (This is an abstract of a proposed presentation and does not necessarily reflect EPA policy.)

2009-A-327-ISES

In Air Pollution Epidemiology, Should We Think Of Ambient Concentrations As A Surrogate For Exposure To Outdoor Pollution Or For Total Exposure To Outdoor And Indoor-generated Pollution? Does It Matter? A History And Critical Review Of The Controversy

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W. E. Wilson; Environmental Protection Agency, Research Triangle Park, NC

There are really three paradigms regarding epidemiologic analyses using air pollutant concentrations measured at a community monitoring site as an indicator of health outcomes. Paradigm 1. Results tell us what changes in health outcomes will occur as a result of changes in outdoor concentrations exposure is irrelevant. Paradigm 2. The key parameter is exposure to outdoor pollution results provide useful information only if outdoor concentrations are reasonably well correlated with personal exposure to outdoor pollution. Paradigm 3. If air pollution affects health outcomes, it must be due to the total exposure to indoor-generated pollution as well as to outdoor pollution that has infiltrated indoors exposures to indoor-generated pollutants are at least as important as exposure to outdoor pollutants results provide useful information only to the extent that outdoor concentrations are representative of total personal exposure. The choice of paradigm also influences research interests and direction. Paradigm 1. No interest in exposure. Paradigm 2. Interested in spatial distribution of outdoor pollution, infiltration of outdoor pollution indoors, and fraction of time spent outdoors correlation of community monitor concentrations with personal exposure to outdoor pollutants a key outcome of research. Paradigm 3. Also interested in indoor-generated pollution and modeling of total personal exposure correlation of community monitor concentrations with total personal exposure a key outcome. This presentation will trace the development of the three paradigms and will describe how the choice of a paradigm narrows the investigators view, influences the direction of research, and affects the interpretation of research results. (This is an abstract of a proposed presentation and does not necessarily reflect EPA policy.)

2009-A-388-ISES

A Bibliometric Analysis Of The Exposure Science Literature

S. D. Peterson,1 M. Goldsmith,2 R. Tornero-Velez,2 D. T. Chang,2 J. C. Johnson,1 C. C. Dary1; 1US EPA, Las Vegas, NV, 2US EPA, Research Triangle Park, NC

By its interdisciplinary nature, exposure science requires input and collaboration from a wide array of scientific fields. In order for exposure science to progress, it must draw on a broad base of scientific knowledge from related fields. Bibliometric analysis of the exposure science literature would highlight and answer questions such as the following. Which institutions or organizations have been the main contributors? Which particular journals are the preferred avenues of publication? Which articles have been turning points in the evolution of exposure science? Has exposure science become progressively more specialized, or is it branching out into other fields? Which types of journals are most commonly cited in the exposure science literature? Which metrics help to track emerging issues of public health concern? This analysis is based on a bibliometric data base compiled from the Science Citation Index (SCI) using keyword searches and spanning the past three decades of exposure science literature. Data analysis and visualization have been performed using a variety of software tools commonly employed in bibliometric analysis.

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2009-A-243-ISES

United States Environmental Protection Agency Human Studies Review Board: Providing Peer Review Of Human Exposure Research

P. I. Lewis, W. E. Lux; United States Environmental Protection Agency, Washington, DC

In 2006, the United States Environmental Protection Agency (EPA) expanded its human studies rule (40 CFR 26: Protection of Human Subjects), beyond the Common Rule to incorporate additional protections for participants in human research subject to regulation by the Agency. A key feature of the expanded rule was the establishment of the Human Studies Review Board, an independent committee chartered under the Federal Advisory Committee Act to provide advice to EPA on scientific and ethical aspects of research with human subjects. Among the Board’s responsibilities was the requirement that it review specific covered human research protocols and reports on which EPA intended to rely in making regulatory decisions under the pesticide laws. Since the Board’s establishment over three years ago, it has focused primarily on human pesticide intentional exposure studies in three areas: (1) research conducted before the rule for the purpose of identifying or measuring a toxic effect (39 studies reviewed by the Board); (2) proposed and completed efficacy studies of topically applied insect repellents (over 20 proposed new repellent efficacy trials reviewed by the Board); and (3) proposed pesticide handler exposure research (overall design of two major occupational exposure monitoring programs reviewed by the Board). The Board’s advice has led to important improvements in research protocols including: (1) stronger scientific design and justification (better sampling design, better inclusion/exclusion criteria, and improved statistical analysis) and (2) improved ethical conduct (better recruitment and consent processes, more thorough minimization of risks to subjects, better safety monitoring and medical management, and better protection of subject privacy). Activities of the Board will be presented, including case studies highlighting advances in human research protections resulting from the review of research by the Board. Disclaimer: Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

2009-A-229-ISES

Environmental Health And Learning And Developmental Disabilities

L. Abulafia; AAIDD, Washington DC, DC

Presentation Description: Learning and developmental disabilities (LDDs ) affect approximately one in six children in the U.S. and appear to be increasing. Though there are many factors that contribute to children’s development such as genetics and social environment, environmental toxicants

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are one of the least researched and most preventable of factors. It is well documented that exposures to lead, mercury and PCBs during critical windows of neurodevelopment can contribute to LDDs. However, there are hundreds of other neurotoxicants (or brain toxicants) and suspected neurotoxicants for which research is sorely needed to better understand how they affect the developing nervous system. The National Academy of Sciences predicts that 25% of developmental and neurological deficits in children are due to the interplay between chemicals and genetic factors and that 3% are caused by exposure to toxic chemicals alone. Given this knowledge, protecting children from exposures to neruotoxicants, starting as early as fetal development is an important public health measure to protect against further incidence of LDDs. This presentation will discuss the current state of scientific evidence with regard to neurotoxic exposures and LDDs. A framework will be presented to further discuss the notion of environmental justice issues within the LDD community and possible differential risks to toxic exposures for this community. Action steps will be provided as opportunities for people living with disabilities to pursue better quality of life through healthy choices in diet, use of every day chemicals, and other safe and healthy choices. Finally, an overview will be provided of national and regional efforts to increase research in the field, promote policy and legislative issues, and educational activities that are protective of children and their health.

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Poster

M-P001d: Monday: Exposure, Risk, Epidemiology - Theme: Risk Analysis

2009-A-305-ISES

Estimation Of Mercury Exposure Through Vaccination

D. Kim,1 G. Kim,2 J. Lee,2 B. Son3; 1School of Environmentak Health, UBC, Vancouver, BC, Canada, 2National Institute of Environmental Research, Inchon, Republic of Korea, 3Department of Occupational and Environmental Medicine, Paik Hospital Faculty of Medicine, Inje University, Busan, Republic of Korea

Introduction: According to The National Survey for Exposure of Hazardous Substances in General Population, Korea, the average concentration of blood mercury was 4.34μg/L in 2005. The following researches to find out sources of mercury exposures showed that the daily intake of mercury through food intake was 18.72μg and through environmental media was 0.11μg. It has been known that some vaccine contain mercury-containing preservative, thimerosal. This study was accomplished to estimate the amount of mercury exposure through vaccination. Method: We examined types and injection amount of vaccine for target contagious diseases based on The National Standard Vaccination List, Korea with the consideration of 70 years of life span from birth to death. Vaccines of 31 products in 11 types used for the national target contagious diseases, 9 products in 3 types used for other vaccinations, and 1 product in 1 type for adult were collected. With the consideration that detection limit of the analyzer is 0.001~10,000 ppb, most of vaccine products containing thimerosal were diluted about 100 times. The mercury content of vaccine was analyzed using the Gold Amalgam Collection Method. Results & Discussion: The mercury concentrations in vaccine were from N.D. to 843.55μg/L and the amount of injected mercury from each vaccination was found to be 0.00~0.42μg/injection. Although no harmful effects have been reported from vaccination, many countries are reducing and eliminating the use of thimerosal as precautionary measures to reduce additional exposure to mercury. Conclusions: It was estimated that the maximum amount of mercury intake through vaccination for one's lifetime(70 years) could be about 22.24μg under the national recommendation list for requisite vaccination in Korea. Even if it was regarded that the amount of mercury intake through vaccination was low, and the adverse effect through vaccination had not been reported, it was recommended to eliminate thimerosal from vaccine.

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2009-A-370-ISES

Assessment Of Exposure And Risks Formed By Enterprises In Ukrainian Industrial Cities

A. Petrosian,1 O. Turos,1 O. Kartavtsev,2 O. Voznyuk,1 H. Davydenko,2 Y. Markevych2; 1Marzeev Institute of Hygiene and Medical Ecology Academy of Medical Sciences of Ukraine, Center of Environmental Health and Risk Assessment, Kyiv, Ukraine, 2Marzeev Institute of Hygiene and Medical Ecology Academy of Medical Sciences of Ukraine, Kyiv, Ukraine

Introduction. Almost two thirds of Ukrainian population is living on the territories that, according to expert assessments, are regarded as areas with poor air quality not corresponding to hygienic requirements. In 2007-2008 Ambient Air Pollution and Risk Assessment Lab jointly with State Institution Marzeev Institute of Hygiene and Medical Ecology in the framework of U.S. EPA projects (grant registration # X4-83199301) and under support of World Bank in Ukraine conducted the research focused on human health risk assessment related to ambient air pollution formed by industrial enterprises of Zaporizhia, Kyiv, Druzhkivka. Objective. To substantiate the main principles of regulatory interventions improvement in air protection and to define risk zones for the exposed population of the studied cities. Methods of research. Program complex ISC-AERMOD View v.6.1.0 (Lakes Environmental Software Group) was implied in average 1-, 24-hour, month and annual pollutant concentrations calculations. Application of this modeling algorithm allowed counting in terrain, land-use peculiarities, annual meteorological observations, source parameters and emission characteristics in calculation procedure. Demographic data (for adult and child population) was processed by ArcGIS 9.x tools and decoded according to the places of residence. Zones of the highest density of exposed population were identified. Risk criteria assessment was completed according to approved U.S. EPA procedure of risk assessment. Results. The research proved the success of human health risk assessment studies aimed at hazard estimation caused by Ukrainian enterprises. In the result of the work cancer and non-cancer risk levels were estimated. In Zaporizhia individual cancer risk from stationary sources was relatively high - 1,9*10-4÷3,7*10-2; Kyiv - 1,2*10-5 ÷8,2*10-3, Druzhkivka - 1,9*10-6 ÷2,5*10-4. Conclusion. The carried out study gave the possibility to define zones f the highest risk and provide a prognostic assessment of health adverse effects among the exposed population for sanitary and conservative interventions on the risk management stage.

2009-A-338-ISES

Environmental Burden Of Disease European Countries

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O. O. Hänninen,1 A. Knoll,2 T. Lim,3 A. Conrad,4 P. Carrer,5 R. Kim,6 A. Pruess-Uestuen7; 1National Institute for Health and Welfare, Kuopio, Finland, 2RIVM, Bilthoven, Netherlands, 3French Institute for Public Health Surveillance, Paris, France, 4UBA, Berlin, Germany, 5University of Milan, Milan, Italy, 6WHO European Centre for Environment and Health, Bonn, Germany, 7WHO Headquarters, Geneva, Switzerland

Environmental factors endanger human health in many ways. Development of policies for the protection of public health as well as research programs bridging the gaps in our understanding of the relationship between the environment and health both need quantitative estimates of the significance of various hazards. Multinational European EBoDE project provides a platform for selection of stressors and health endpoints and assess the impacts in a comparable way across the countries and making assessment methods available for new countries. The objective of the project is to update the previous assessments, to add stressors relevant to the European region, to provide harmonized EBD assessments for participating countries, and to develop and make available the methodology and databases for other countries. Specifically the project intends to create (i) Full comparability of the quantifications and ranking of the EBDs from environ-mental exposures between countries and between exposure agents (ii) Unified disability weighing of the different risks and (iii) Assessments of variation and uncertainty in the input parameters and results. Criteria for the selection of environmental stressors are based on public health relevance, high individual risks, public concern and economical impacts. Stressors were ranked into three categories with the first priority group consisting of benzene, dioxins (including furans and dioxin like PCBs), environmental tobacco smoke (ETS), formaldehyde, lead, noise, ozone, particulate matter and radon (in alphabetical order). The most recent exposure data is collected and dose-responses are described using relative risks to calculate attributable fractions. The risks are ranked using disability adjusted life years (DALY) estimated from WHO burden of disease data. Earlier rankings show that the risks differ by orders of magnitude, posing significant implications for policies and research.

2009-A-427-ISES

A Full Chain Mechanistic Approach Assessing Exposure To Multi-source Air Pollutants And Cancer Risk

D. Sarigiannis, A. Gotti, S. Karakitsios; JRC, Ispra (VA), Italy

The aim of the present study is the construction of an integrated modelling environment for assessing exposure and carcinogenic risks to environmental stressors under a robust biological basis. Thus, an integrated modelling environment was compiled in a single computational platform (asclXtreme) including calculation of emissions, dispersion, exposure modelling, internal dose and cancer risk. The main component of the platform is a generic Physiology Based ToxicoKinetic model, which can be properly modified and parameterized for the needs of individual stressors. Uncertainty and variability of the

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affecting parameters were estimated in each stage through Marcov Chain Monte Carlo. The platform was parameterized to address four different case studies assessing lung cancer (by 4-(N-nitrosomethylamino)-1-(3-pyridyl)-1-butanone and As), leukemia (by benzene) and nasopharyngeal cancer (by formaldehyde) due to ETS (environmental tobacco smoke) exposure, reconstruction of exposure pattern of benzene based on biomarkers data (reverse modelling) and evaluating the impact of two different policy scenarios (traffic renewal and smoking banning) aiming in reducing leukemia risk due to benzene exposure in Greece and Finland. The results indicated that the associated risk for lung cancer, leukemia and nasopharyngeal cancer per individual is up to 3.10-4, 6.10-6 and 1.10-7 respectively under the typical ETS exposure scenarios in the EU. Pattern reconstruction of exposure to benzene based on urinary metabolites data was successfully performed (90% of the observed concentrations were within the predicted values). Predictive capacity depends on the reliability of the chosen biomarker and the consistency of sampling protocol. Finally, the evaluation of different policy scenarios regarding traffic measures and smoking banning revealed a different response in different countries in the EU (leukemia risk reduction equal to 70% and 10% under traffic policy scenarios, 15 and 60% under smoking banning for Greece and Finland respectively), attributed to the individual characteristics of traffic composition, time activity patterns and environmental conditions.

2009-A-436-ISES

Interpretation Of Urinary And Blood Benzene Biomarkers Of Exposure For Non-occupationally Exposed Individuals

S. M. Arnold,1 P. S. Price,1 S. H. Robison,2 M. F. Hughes,3 P. J. Boogaard4; 1The Dow Chemical Company, Midland, MI, 2The Procter and Gamble Company, Cincinnati, OH, 3United States Environmental Protection Agency, Research Triangle Park, NC, 4Shell International B.V., The Hague, Netherlands

Non-occupational exposure to benzene occurs primarily through inhalation of air impacted by motor vehicle exhaust, fuel sources, and cigarette smoke. This study relates published measurements of benzene biomarkers to air exposure concentrations. Benzene has three reliable biomarkers of exposure for non-occupationally exposed individuals: urinary benzene, urinary S-phenylmercapturic acid (SPMA), and blood benzene. Published linear regression equations for benzene and SPMA in urine were used to relate urinary measurements to average air concentrations, and for comparison to the USEPA reference concentration (RfC) of 0.030 mg/m3 (9 ppb). The urinary benzene concentration relating to the USEPA RfC was 0.24 ng/L (range 0.04 to 0.46 ng/L). This compares to urinary benzene concentrations (central tendency values) reported in the literature ranging from 0.11 to 0.25 ng/L for non-smokers. As expected, the urinary benzene concentration for smokers was higher ranging from 0.19 to 1.78 ng/L. The urinary SPMA concentration relating to the RfC was 3.0 ug/g creatinine (cr.) (range = 0.1 to 6.8 ug/g cr.). This compares to urinary SPMA concentrations (central tendency values)

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reported in the literature ranging from 0.3 to 6.5 ug/g cr. for non-smokers. Similarly to the results for urinary benzene, the urinary SPMA concentration for smokers was higher ranging from 0.5 to 9.9 ug/g cr. The results of this analysis indicate that for non-occupational exposure, urinary benzene and SPMA levels correlate well with reported ambient air benzene levels and non-smokers are generally at or below the urinary biomarker level corresponding to the USEPA RfC. An evaluation of the available blood benzene data is underway. The most recent CDC-NHANES data for blood benzene indicate levels of 0.017 to 1.4 ng/ml, which are consistent with ranges previously reported in the literature. (This abstract does not represent US EPA policy)

2009-A-459-ISES

Use Of Biomonitoring Data As Surrogate Data In Regulatory Decisions For Occupational Exposures To Pesticides

J. Johnston,1 B. Polakoff,1 J. Driver,2 J. Ross3; 1Exponent, Washington, DC, 2infoscientific.com, Manassas, VA, 3Gem Quality Risk, Carmichael, CA

Biomonitoring is regarded as the gold standard for measuring exposures in affected populations, but biomonitoring studies are expensive and difficult to conduct, especially compared to passive dosimetry exposure studies. For regulatory decision-making in support of pesticide registrations, the USEPA generally relies on passive dosimetry exposure data. However, USEPA has used biomonitoring data collected from pesticide mixer/loaders and applicators in select cases to support agrochemical registrations. Because biomonitoring data are considered to be chemical-specific, USEPA has so far not used biomonitoring data as surrogate data to estimate handler exposures to other chemicals. A generic approach for the use of biomonitoring data for one chemical (the reference chemical) as surrogate data for another chemical (the subject chemical) is proposed. The proposed approach involves a few simple steps: (1) estimate exposure to the reference chemical from reported excretion of metabolite or parent, (2) express exposure to the reference chemical on mg/kg/d basis, and (3) estimate exposure for the subject chemical, adjusting for relative application rates and dermal absorption. The use of biomonitoring data as surrogate data for other chemicals is appropriate in regulatory decision-making when certain criteria are met: (1) use pattern, method of application and use of personal protective equipment and/or engineering controls are similar, (2) physicochemical properties, formulation type and physical form are similar, and (3) relative rates of dermal absorption for the two chemicals are known. For the surrogate approach to be appropriate, the reference and subject chemicals need not be in similar classes, nor need they have similar mechanisms of action or similar distribution, metabolism and excretion profiles, although such data would increase confidence in the proposed surrogate approach. The proposed approach is illustrated with example calculations using biomonitoring data for a reference chemical as the basis for exposure estimates for a hypothetical subject chemical.

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2009-A-476-ISES

The Application Of Biomonitoring Data In Risk Assessment: A Benzene Case Study

S. H. Robison,1 S. Arnold,2 P. J. Boogaard,3 R. O'Lone4; 1Procter and Gamble Company, Cincinnati, OH, 2Dow Chemical Company, Midland, MI, 3Shell Health, The Hague, Netherlands, 4HESI, Washington, DC

The generation of biomonitoring data has undergone a dramatic increase globally while the sensitivity of analytical methods now permits the measurement of very low levels of chemicals in human tissues. Although detection of low levels of chemicals in human tissues offers evidence of exposure, the ability to integrate this information into a risk based context is limited. Furthermore, it is difficult to relate these low levels to any potential adverse health outcome. In the absence of exposure pathway information, it is also difficult to relate measurements of chemicals back to sources of exposure or to develop effective risk management strategies. Recently reports have been published by the National Academy of Sciences, ILSI Health and Environmental Science Institute (HESI), and the European Centre for Ecotoxicology and Toxicology of Chemicals (ECETOC) highlighting many of the key issues associated with interpreting biomonitoring data. To provide perspective on approaches for integrating biomonitoring data into a risk-based context, HESI has developed a case study using benzene as a model compound. Several published biomonitoring datasets are available for benzene, a chemical that will also be included in the Centers for Disease Control and Prevention’s (CDC) National Health and Nutrition Examination Survey (NHANES). In addition, there is a wealth of human epidemiology and toxicology data for benzene that offers the potential to examine the relationship between exposure and human health effects. This case study evaluated biomarkers of benzene exposure in both urine and blood. Furthermore occupational and general population exposures to benzene have been evaluated. These evaluations highlight the limitations for applying biomarkers of exposure in urine and blood.

2009-A-345-ISES

Use Of A Simple Pharmacokinetic Model To Characterize The Temporal Variability Of Di-2-ethylhexyl Phthalate Metabolites In Urine

M. N. Lorber,1 L. Aylward2; 1US Environmental Protection Agency, Washington, DC, 2Summit Toxicology, Falls Church, VA

Once an exposure to Di-2-ethylhexyl phthalate, DEHP, occurs, the parent diester phthalate rapidly hydrolyzes to the monoester, MEHP, and then to 5oxo-MEHP, 5OH-MEHP, 5cx-MEPP, and 2cx-MMHP. All metabolites are excreted with urine and feces within hours. A simple pharmacokinetic model has been developed which takes intake doses of DEHP and predicts concentrations of the five metabolites in blood and urine.

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The background exposure of Americans to DEHP is approximately 1.5 µg/kg-day. This paper will review the structure and calibration of the model, and the derivation of this background exposure. External evidence will be presented showing that this exposure is primarily from food. Then multiple scenarios will be run to evaluate the effect of the timing of exposure to concentrations found in urine. Specifically, three scenarios include: 1 exposure equaling this daily total to occur at 9 am (breakfast), 3 exposures at 1/3 the daily total at 9 am, 12 pm, and 6 pm (mealtimes), and 5 exposures at 1/5 the daily total at 3-hr intervals from 9 am to 9 pm. An example result from this analysis is the timing and magnitude of the peak concentration of the primary monoester metabolite MEHP. With a single exposure, the peak concentration in urine is found in the morning hours at about 11.6 µg/L; with 3 exposures, the peak concentrations are found in the afternoon towards the evening hours at about 6.3 µg/L; and with 5 exposures, the peak concentration is about 6.6 µg/L experienced in the late afternoon, early evening hours. This compares to the average MEHP concentration found in NHANES of 4.1 µg/L. Another analysis looks at the ratios of three metabolites and shows how these ratios can inform on the timing of the exposure.

2009-A-481-ISES

Changes In Gene Expression And Methylation In Prostate Cells Exposed To Bisphenol A

M. Sienkiewicz, J. Gomes; Department of Cellular and Molecular Medicine, University of Ottawa, Ottawa, ON, Canada

Promoter hypermethylation and silencing of associated genes is common in prostate cancer. Hypermethylation of GSTP1 gene occurs in 90% of prostate cancers. Loss of GSTP1 function may increase the susceptibility of prostate cells to damage by environmental carcinogens. RASSF1A promoter methylation is also common in prostate cancer occurring in 54-96% of prostate tumors. Exposure to estrogenic endocrine disrupting compounds (EDCs) can result in abnormal DNA methylation and consequently alter development of reproductive tracts or cause cancer. Bisphenol A (BPA) is a monomer of polycarbonate plastics used in many products such as inner coating of food cans, dental composites and beverage cans. Early life exposure to BPA can increase the susceptibility of prostate gland to tumor development later in life by altering the methylation and expression of PDE4D4 gene. Methylation of promoter regions and alterations in the expression of genes responsible for DNA damage repair GSTP1 and cell cycle control and tumor suppressor gene RASSF1A was examined in time and dose dependent BPA exposures of prostate cells. Cells are first grown in hormone free medium for 6 days, after which the medium is replaced with different concentrations of BPA at 0, 10 nM, 100 nM,1 µM and 10µM. Cells from both treated samples and controls are harvested at 8, 24, 36 and 48 h after exposure. Cell proliferation and viability was measured in the exposed and unexposed cells. Genomic DNA was used to examine methylation using primers specific for methylated or unmethylated DNA. Gene expression levels were quantified using Real Time Quantitative PCR analysis.

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Exposure studies of the potential effects of environmental agents such as BPA on expression of critical genes and DNA methylation could help understand the role that exogenous hormone play in prostate cancer.

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Poster

M-P001e: Monday: Exposure, Risk, Epidemiology - Theme: Biomonitoring-Exposure

2009-A-315-ISES

Concurrent Exposures To Lead, Mercury And Cadmium Among Women (16-49 Years) And Children (1-5 Years) By Race And Poverty Level: National Health And Nutrition Examination Survey 2001-2006

O. C. Nweke,1 D. Axelrad,1 T. J. Woodruff2; 1US Environmental Protection Agency, Washington, DC, 2University of California, San Francisco, Oakland, CA

In this study, we assessed concurrent exposure to lead, mercury and cadmium among children (1-5y) and women of childbearing age (16-49y) in the US population using data from NHANES for the survey years 2001-2006. We analyzed the representation of each socio-demographic group among individuals whose blood levels for each of the three metals is in the upper tail of the population- and metal-specific distribution. We identified participants in both study populations with lead, mercury and cadmium blood levels at or exceeding the respective population- and metal-specific 75th percentiles. We then estimated prevalence of these individuals among each race/ethnicity category and by socioeconomic status. Each participant’s socioeconomic status was defined using the poverty income ratio (PIR), dichotomized into PIR<1 and PIR≥1. Four race/ethnicity categories were included in the analysis. The 75th percentiles for lead, mercury and cadmium were 2.37µg/dL, 0.53µg/L and 0.17µg/L respectively among children (1-5y), and 1.3µg/dL, 1.6µg/L and 0.59µg/L respectively in women (16-49y). Among children (1-5y) and women (16-49y), 3.7% and 3.3% respectively had blood levels ≥75th percentile for each of the three metals. The prevalence of individuals with blood levels ≥75th percentile for each of the three metals was highest amongst non-Hispanic black children (1-5y) (9.6%), and amongst women 16-49y who self identified as “Other Race” (9%). This group includes Asians and Pacific Islanders. Prevalence rates among children (1-5y) and women (16-49y) were higher among those living below poverty level compared to individuals at or above poverty level. These results suggest socio-demographic patterns among children (1-5y) and women (16-49y) with exposure in the upper tails of the distributions for all three metals. This analysis presents an approach for identifying population groups with higher burdens of exposure to multiple environmental agents relative to the general population or specific population groups when individual data are available.

2009-A-391-ISES

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Assessment Of Urinary Selenium And Arsenic Concentrations Among Residents In Arizona And Sonora, Mexico

J. Roberge,1 R. Harris,1 D. Roe,1 M. Mercedes,2 L. Gutierrez Millan3; 1University of Arizona, Tucson, AZ, 2Instituto de Tecnologica de Sonora, Ciudad Obregon, Mexico, 3Universidad de Sonora, Hermosillo, Mexico

Introduction: Severe health effects have been observed in populations where there has been long term exposure to drinking water rich in inorganic arsenic (As). In a few smaller studies, urinary concentrations of selenium (Se) have been shown to be associated with an increase in As excretion and with the distribution of As species (monomethylarsenate (MMA) and dimethylarsenate (DMA)). Results from smaller studies are conflicting as to the ability of Se to inhibit the conversion of MMA to DMA. This study investigates the association between urinary As species and urinary Se concentrations using data collected from the Binational Arsenic Exposure Survey. Methods: This analysis utilized 258 participants from Mexico and 215 participants from Arizona. All participants were over the age of 18 and had lived in their home for at least one year. Demographics, health history, and behavioral characteristics were collected during a household interview. First morning urine samples were collected and analyzed for As and Se concentration using inductively coupled plasma-mass spectrometry (ICP-MS). Results: Urinary total As concentrations ranged from 1.55 to 1121.0 µg/L, urinary inorganic As concentrations ranged from 0.87 to 1146.5 µg/L, and urinary Se concentrations ranged from 6.40 to 556.41 µg/L. The Spearman correlation coefficient between Se and total As was 0.30 (p<0.001), 0.24 (P<0.001) between Se and inorganic As and -0.19 (p<0.001) between Se and percent DMA. Discussion: In this preliminary analysis, there was a positive association between Se and total As and between Se and inorganic As concentrations. There was a negative association between Se concentration and percent DMA. Further analysis will incorporate a random effects model to account for the correlation of participants within a household, confounders, and the assessment of creatinine adjustment.

2009-A-477-ISES

Current-use Pesticide Urinary Metabolite Levels During Pregnancy In Women Living In An Agricultural Community

R. Castorina,1 A. Bradman,1 L. Fenster,2 D. B. Barr,3 R. Bravo,3 M. E. Harnly,2 T. E. McKone,1 E. A. Eisen,1 B. Eskenazi1; 1Center for Children's Environmental Health Research, UC Berkeley School of Public Health, Berkeley, CA, 2Division of Environmental and Occupational Disease Control, California Department of Public, Richmond, CA, 3Centers for Disease Control and Prevention, Atlanta, GA

We measured 34 metabolites of current-use pesticides in two urine samples collected from 538 pregnant women living in the Salinas Valley, CA. The precursor compounds of

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these metabolites included fungicides, carbamate, organochlorine, organophosphorous (OP) and pyrethroid insecticides, triazine and chloroacetanilide herbicides, naphthalene, pentachlorphenol, and ethylenethiorurea (ETU), a toxic metabolite of the ethylene-bisdithiocarbamate fungicides. The detection frequencies of the metabolites in CHAMACOS ranged from 0% to 81%, with eight metabolites detected in both urine samples at frequencies averaging over 50%. Of the eight frequently detected compounds (2,4- and 2,5-dichlorophenol, 1- and 2-naphthol, ortho-phenylphenol (ORTH), para-nitrophenol, 2,4,6-trichlorophenol and 3,4,6-trichloro-2-pyridinol (TCPy)), seven may be related to current home or agricultural pesticide use in the Salinas Valley. More than 78% of women in this study had detectable levels of at least one of the 10 OP pesticide specific metabolites. In addition, we found that malathion dicarboxylic acid and 1-naphthol, metabolites of pesticides commonly used in strawberry production in the Salinas Valley (malathion and carbaryl), were significantly higher at the 90th percentile among women currently working in strawberry fields (p<0.05). Finally, we compared urinary metabolite concentrations measured in prenatal samples with U.S. national reference data for 224 pregnant women sampled by NHANES (1999-2002). While, in general, detection frequencies were not statistically different between the CHAMACOS cohort and pregnant women in NHANES, the distributions of six of the most commonly detected compounds were significantly higher among the CHAMACOS women (2,4- dichlorophenol: Kolmogorov-Smirnov D=0.36; 2,5-dichlorophenol: D= 0.34; 1-naphthol: D= 0.25; ORTH: D=0.32; 2,4,6- trichlorophenol: D=0.44; and TCPy: D=0.29; p-values<0.01). Results suggest similar routes of precursor pesticide exposure as the national sample plus an additional burden in the CHAMACOS cohort from living and working in an agricultural area.

2009-A-246-ISES

The Bhopal Gas Disaster Twenty Five Years Later

P. Barn,1 S. Mulay,2 S. Sarangi3; 1British Columbia Centre for Disease Control, Vancouver, BC, Canada, 2Memorial University of Newfoundland, St. John's, NL, Canada, 3Sambhavna Trust Clinic, Bhopal, India

Background: The Bhopal gas disaster occurred on the night of December 2, 1984 with the release of methyl-isocyanate gas from the Union Carbide pesticide plant, resulting in thousands of deaths. Almost 25 years later, the plant site has not been decontaminated which has raised concerns about potential groundwater contamination resulting from leaching of chemicals still stored on-site. Limited environmental monitoring and sampling reports indicate the presence of toxic chemicals in soil and water samples collected adjacent to the plant. Limited exposure assessment to these chemicals has been conducted, representing an important gap in assessing exposure-related health effects among residents consuming potentially contaminated groundwater. To address this gap, a pilot study was conducted following approval of study design by the Ethics Committee of Sambhavna Trust Clinic (STC), the sponsor of this research project. Methods: A survey was conducted by STC community health workers to establish the

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household drinking water source in communities surrounding the plant. Permission was sought from parents and blood samples were collected from children (6-10 years of age) belonging to one of two exposure groups: 1. children whose primary drinking water source was public hand pumps supplying groundwater (n=27), and 2: children whose primary drinking water source was community tank water collected at a source located outside of the study area (n=16). Samples were tested for dichlorobenzene, trichlorobenzene, and chloroform using gas chromatography (Sargam Laboratory, Chennai, India). Results: All samples were below the detection limit (0.10 ppm) for the three compounds. Discussion: Many factors may have led to the negative results, including improper storage and shipment conditions of samples. Environmental contamination continues to be an important issue in the communities surrounding the plant. Further biomonitoring work needs to be conducted in order to ascertain the level of risk to community members exposed to potentially contaminated drinking water.

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Poster

M-P001f: Monday: Exposure, Risk, Epidemiology - Theme: Biomonitoring-Emerging Research & Methods

2009-A-276-ISES

Analysis Of Urinary 4-aminobiphenyl Metabolites In Nonsmokers And Smokers By Lc And Gc Tandem Mass Spectrometry

T. Seyler, L. Reyes, J. Bernert; CDC, Atlanta, GA

Cigarette smoking is a significant risk factor for human lung and bladder cancer. Furthermore, exposure of nonsmokers to secondhand tobacco smoke (SHS, also known as ETS) has been linked to a potentially increased risk of bladder cancer. SHS has been identified as an airborne toxic substance that may cause and/or contribute to death or serious illness. Three aromatic amines found in cigarette smoke, o-toluidine, 2-aminonapthylene, and 4-aminobiphenyl (4-AB) are well-established human bladder carcinogens presumably acting via the formation of adducts to DNA. The amines may be metabolized in the liver to acetylated or glucuronidated forms, or oxidized to a hydroxylamine which may react to form adducts with proteins and DNA. Free, acetylated and glucuronidated 4-AB are excreted in urine, although aryl amine glucuronides can be converted to the native parent compounds under acidic condition. These products may be useful biomarkers for monitoring active cigarette smoking or short term SHS exposure. In this study we describe the preliminary identification of N-acetyl-4-AB and 4-AB glucuronide in urine samples of smokers and nonsmoker, and we report the efficiency of acidic, basic, and enzymatic hydrolysis using either LC/MS/MS or capillary GC/MS/MS for analysis. The effect of hydrolysis conditions on the metabolites was also examined with urine samples from eight nonsmokers and five smokers. Acidic hydrolysis was the most efficient, approximately 2.5 to 4 times better than basic hydrolysis, whereas enzymatic hydrolysis (β-glucuronidase with 1M E. coli or Helix) was inactive. However, we have found that additional N-acetyl-4-AB may be formed under acidic hydrolysis conditions. Further studies are currently being conducted to identify the optimum conditions for analysis, and to quantify the amounts of N-acetylated and glucuronidated 4-AB and other aromatic amine that are present naturally in urine of smokers and nonsmokers, and these results will be described.

2009-A-255-ISES

Measurement Of Ethyl Methanesulfonate In Human Plasma And Breast Milk Samples Using High-Performance Liquid Chromatography-Atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry

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R. D. Whitehead, M. A. Montesano, N. K. Jayatilaka, P. Kuklenyik, M. D. Davis, L. L. Needham, D. B. Barr; Centers for Disease Control and Prevention, Atlanta, GA

Ethyl methanesulfonate (EMS) is a mesylate ester known to be a mutagenic, teratogenic, and possibly carcinogenic. Mesylate esters have been found in pharmaceuticals as contaminants, formed during the manufacturing process. We developed and validated a method for detection of trace analysis (ng/mL levels) of EMS in human plasma and breast milk. The sample preparation involved liquid/liquid extraction with ethyl acetate using Hydromatrix™ and the ASE 200 Accelerated Solvent Extractor. The extracts were separated by high-performance liquid chromatography (HPLC) using a HILIC column. The detection was performed with a triple quadrupole mass spectrometer (TSQ Quantum, Thermo Electron Corporation) using atmospheric pressure chemical ionization in negative ion mode and multiple reaction monitoring. The use of a surrogate internal standard in combination with HPLC-tandem mass spectrometry provided a high degree of accuracy and precision. The extraction efficiency was greater than 70%. Repeated analyses of plasma and breast milk samples spiked with high (100 ng/ml), medium (50 ng/ml) and low (5 ng/ml) concentrations of the analytes gave relative standard deviations of less than 20%. The limit of detection was in the range of 1 ng/ml for both matrices.

2009-A-322-ISES

Measurement Of Acephate, Methamidophos, O-methoate, Dimethoate, Ethylenethiouria And Propylenethiourea In Human Urine Using 96-well Plate Sample Preparation And Hplc-ms/ms

N. K. Jayatilaka, M. A. Montesano, R. D. Whitehead, L. L. Needham, D. B. Barr; CDC, Atlanta, GA

Acephate, methamidophos, o-methoate and dimethoate are organophosphorus pesticides; ethylenethiouria and propylenethiourea are two metabolites from the bisdithiocarbamate fungicide family. They are some of the most widely used pesticides and fungicides in agriculture both domestically and abroad. The existing HPLC-MS/MS method for the measurement of these compounds in human urine was improved by using a 96-well plate format sample preparation and HPLC-MS/MS over a concentration range of 0.125 - 50 ng/ml. Stable 13C6 labeled acephate, ethylenethiouria and methamidophos were used as internal standards. The sample preparation procedure, in the 96-well format with a 1 ml urine sample size, utilizes lyophilization of samples followed by extraction with dichloromethane. The analytes were chromatographed on a Zorbax SB-C3 (4.6 × 150 mm, 5.0 μm) column with gradient elution by using 0.1% formic acid in aqueous solution (solvent A) and 0.1% formic acid in methanol (solvent B) mobile phase at a flow rate of 1ml/min. Quantitative analysis was done by atmospheric pressure chemical ionization source in positive ion mode using multiple reaction monitoring of the precursor-to-product ion pairs for the analytes on a TSQ Quantum Ultra HPLC-MS/MS. Repeated analyses of urine samples spiked with high (15 ng/ml), medium (5 ng/ml) and low (1 ng/ml) concentrations of the analytes gave relative standard deviations of less than 20%.

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The limits of detection were in the range of 0.005 - 0.05 ng/ml. The improved sample preparation doubled our analytical throughput.

2009-A-346-ISES

Measurement Of Dialkylphosphate Metabolites Of Organophosphorous In Human Urine Using 96-well Plate Sample Preparation And High-performance Liquid Chromatography-atmospheric Pressure Chemical Ionization Tandem Mass Spectrometry

M. S. Odetokun, M. A. Montesano, R. D. Whitehead, L. L. Needham, D. B. Barr; CDC, Atlanta, GA

The aim of this study was to develop a fast and accurate liquid chromatograpy-tandem mass spectrometry method for the quantitative measurement of the following six common dialkylphosphate (DAP) metabolites of organophosphorous (OP) insecticides: diethylphosphate (DEP), dimethylthiophosphate (DETP), dimethyldithiophosphate (DEDTP), dimethylphosphate (DMP), dimethylthiophosphate (DMTP) and dimethyldithiophoshate (DMDTP). These metabolites are common to the majority of OP insecticides but do they not retain any of the structure unique to the pesticides from which they were derived, so it is impossible to identify individual pesticides from these metabolites. However, because these metabolites are common to the majority of OP insecticides, they can provide information about exposure to the OP insecticide class. The sample preparation included automated solid phase extraction using weak anion exchange sorbent on a 96-well plate performed with a TomTec extraction unit. The six metabolites were separated with a HILIC column under isocratic conditions. The detection was carried out with a triple quadrupole mass spectrometer with an ESI probe in negative ion mode using multiple reaction monitoring. Repeated analyses of urine samples spiked at 150 ng/mL, 96 ng/mL and 32 ng/mL with the analytes gave relative standard deviations of less than 20%. The extraction efficiency ranged from 40% to 98%. The limits of detection were in the range of 0.03 ng/ml to 0.5ng/ml. Using this new method, our throughput is 1,152 samples per week, effectively quadrupling our previous throughput. The present method is safe quick and sensitive enough to be used in routine and emergency biological monitoring of occupational and non-occupational exposure to organophosphates.

2009-A-403-ISES

Measurement Of Aldehydes In Exhaled Breath Condensate

J. Gong, L. Zhang, J. Zhang; University of Medicine and Dentistry of New Jersey, Piscataway, NJ

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Background: Aldehydes, e.g. formaldehyde, acetaldehyde, acrolein, and malondialdehyde (MDA), have been detected in the exhaled breath condensate (EBC) of human. The most commonly used method for MDA has been based on enzymatic immunoassays which are not compound specific and, thus, do not have high reproducibility. Methods for other aldehydes often utilize mass spectrometry (MS) techniques coupled with an HPLC or GC system. The methods can be expensive and are limited to the laboratories having MS capabilities. Purpose: The goal of this study is to develop and evaluate HPLC-fluorescence based methods for analyzing aldehydes in EBC. Method: Aldehydes, including formaldehyde, acetaldehyde, acrolein, etc, will be analyzed using an HPLC-fluorescence technique after aldehydes are derivatized with a fluorescence-generating agent, dansylhydrazine (DNSH). EBC sample will be transferred onto a DNSH-coated cartridge. After reaction between aldehydes and DNSH, the derivatives will be extracted with acetonitrile and the solution will be injected into HPLC-fluorescence system for detection. MDA will be analyzed using an HPLC-fluorescence technique after aldehydes are derivatized with thiobarbituric acid (TBA). EBC sample will be spiked into a solution containing phosphoric acid and TBA. After reaction between MDA and TBA, NaOH will be added to neutralize the solution which is ready to be injected into HPLC-fluorescence system for the detection. Results: Both methods allow us to detect aldehydes in EBC collected from “normal” persons. The detection limits are 0.66 µM, 0.45 µM, 0.35, and 4.5 nM µM for formaldehyde, acetaldehyde, acrolein, and MDA, respectively. The analytical precisions, measured as RSD of replicate analyses, are 5%, 10%, 10%, and 2% for formaldehyde, acetaldehyde, acrolein, and MDA, respectively. Method recoveries are tentatively 129%, 86%, 44%, and 76% for formaldehyde, acetaldehyde, acrolein, and MDA, respectively. The methods are currently being optimized for improved recoveries. Keywords: oxidative stress, aldehydes, air pollution, exhaled breath condensate (EBC), exposure, biomarkers

2009-A-635-ISES

Approaches To Making Measurements Of Nano-particles In Human Tissue

M. G. Nishioka, W. A. Ivancic; Battelle Memorial Institute, Columbus, OH

Dermal penetration of nano-particles from consumer products is a current health concern because nano-sized particles do not have the same properties as the bulk chemical; in some cases, bulk inert chemicals (such as silver) become highly reactive when nano-sized. For this reason, studies need to be conducted to assess exposure and potential risks. The structure of skin and the pros and cons of various analytical measurement techniques need to be considered when choosing exposure assessment measurement methods. In our current study of dermal penetration of inorganic nano-particles, we have found that tape-stripping with both ICP-MS and confocal Raman analyses provides a very good complement to in situ confocal Raman analyses of skin. The depth profiling capability of

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confocal Raman, though, must be balanced against its rather weak signal and natural skin fluorescence. Additionally we have found that it is essential to distinguish between true nano-particles that penetrate through the tightly-packed bricks-and-mortar structure of the stratum corneum and agglomerated nano-particles that fall into skin pores and appear to be present below the stratum corneum. Results from these different measurement methods will be discussed.

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Symposium

M-SY301: Exposure Modeling for Mobile Populations

Recent air quality studies have highlighted that important differences in pollutant concentrations can occur over the day and between different locations. At the same time, the location of individuals also varies over space and time causing a large geographical and temporal variation in the number of people present at any location during the day. Traditional exposure studies that link concentrations with population data however do not always take into account the temporal and spatial variations in both concentrations and population density. Most existing methods of air pollution exposure estimation for example take little or no account of the mobility of the study population. Census data, which reflect residential location only and ignore daily travel to other locations, are commonly used in epidemiology studies. This ‘static’ approach may contribute to exposure assessment error as people in reality spend a significant portion of daytime hours away from home. As a result, both epidemiological studies and health risk assessments typically fail to recognize the wide variations in exposure that may occur due to differences in time activity and lifestyle. To establish an improved assessment of exposure, it is therefore necessary to take into account that people move during the day and are exposed to pollutant concentrations other than at their home address. In this symposium we would like to focus on exposure methods and studies that take into account the mobility of people to calculate exposure estimates (i.e. a dynamic exposure approach). We will mainly explore how air pollution exposure is affected by taking into account people’s mobility patterns, but we will also discuss the exposure while traveling.

2009-P-115-ISES

A Disaggregated Analysis of Nation-Wide Exposure Estimates in The Netherlands

C. Beckx; Flemish Institute for Technological Research, Mol, Belgium

We present an integrated model chain for the determination of nation-wide exposure estimates that incorporates temporally and spatially resolved information about people’s location and activities (obtained from the activity-based transport model 'ALBATROSS') and about ambient pollutant concentrations (obtained from the 'AURORA' dispersion model). The evaluation of population level exposure to NO2 at different time-periods, locations, for different subpopulations (gender, socio-economic status) and during different activities (residential, work, transport, shopping) in the Netherlands is chosen as a case-study to point out the new features of this methodology that takes into account a mobile population.

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2009-P-112-ISES

Evaluation of Exposure to Diesel Particulate Matter in the South Coast Air Basin

J. Marshall; Department of Civil Engineering, University of Minnesota, Minneapolis, MN

Census data, which reflect residential location only and ignore daily travel to other locations, are commonly used in epidemiology studies. This investigation explores how air pollution exposures are affected by people’s daily mobility patterns. We evaluated exposure to diesel particulate matter in the South Coast Air Basin using three approaches: (1) Census data for the entire population (~16 million), (2) geocoded travel diary data indicating spatial mobility patterns for 25,000 survey respondents, and (3) the same travel diary data but with mobility patterns removed. Hourly outdoor concentrations for year-2005 are estimated using the CAMx air dispersion model. Exposures indoors and in vehicles are estimated using a Monte Carlo exposure model. Our results explore how exposures would be affected by emission reductions from specific sources, thereby establishing exposure-based prioritization of emission reductions. Our work sheds light on how results of this prioritization depend on whether one incorporates travel patterns.

2009-P-113-ISES

Exposure Modeling for a Mobile Population in the EU Project GENESIS

D. Briggs; Department of Epidemiology and Public Health, Imperial College London, London, United Kingdom

Most existing methods of air pollution exposure estimation take little or no account of the mobility of the study population. As a result, both epidemiological studies and health risk assessments typically fail to recognise the wide variations in exposure that may occur due to differences in time activity and lifestyle, and vulnerable groups are often missed. The effects of intervening in the system (e.g. via traffic management or urban planninf) are also not well quantified. As part of a larger EU project to generate software tools for air pollution management (GENESIS), we are developing techniques to link air pollution dispersion models, time activity data and micro-environmental factors to provide 24-hour exposure profiles of study individuals. Methods are being tested and demonstrated through a series of case studies, including an analysis of the effects of the Low Emission Zone in London, health outcomes in a birth cohort in Bradford, and the health impacts of major air pollution episodes in south-east England.

2009-P-114-ISES

Determination of a Bias Factor Associated with Residence-Only Based Exposure

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E. Setton; University of Victoria, Victoria, Canada

We calculate the direction and degree of a bias factor associated with using a residence-only based estimate of pollution concentration as a measure of exposure in relative risk estimates. The bias factor is a multiplier that can be applied to estimates of relative risk using residence-only based estimates instead of mobility-based estimates of exposure. Datasets from two study areas (South Coast Air Basin, California, US and Vancouver, British Columbia, Canada), each of which include paired estimates of exposure at residential locations only and exposure including mobility, are used to investigate the direction and degree of the bias factor. We hereby assume that mobility-based estimates are closer to true exposure measures than are estimates based on residential location only, and employ general error theory to calculate a bias factor.

2009-P-116-ISES

In-Transport Exposure Estimation: Exposure of Cyclists to Air Pollution in Belgium

L. Int Panis; Flemish Institute for Technological Research, Mol, Belgium

Exposure methods that ignore people’s travel behavior do not take into account the exposure on locations other than the home address. Moreover, the exposure while traveling is also ignored whereas people being in-transport often experience high concentrations of air pollutants and therefore need to be examined even more. We present two sets of new data on health risks for commuter cyclists that were collected during the SHAPES-project. Cyclists are exposed to risks from inhalation of air pollution. Exposure was determined statistically at the national scale and, using portable instruments, in the immediate vicinity of cyclists, including the inhaled fraction.

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Symposium

M-SY302: Cookstove Intervention and Indoor Air Pollution Studies in the Developing World – Exposure Assessment and Health Impact - Session B

Target Audience: indoor air pollution exposure assessment/environmental epidemiology researchers, clinicians, other researchers interested in exposure to woodsmoke and related indoor air pollution from cookstoves and replacement intervention stoves in the developing world. Objectives: 1. To review the state of the knowledge regarding recent and current cookstove intervention studies and programs in the developing world – including exposure assessment and environmental epidemiologic aspects of these programs; 2. to review lessons learned from past cookstove intervention studies and programs, including exposure assessment tools, health outcome evaluation, stove design/installation/maintenance issues, and policy related issues. Summary of session content: It is estimated that around 50% of the world’s population, with as many as 90% in some developing countries, rely on biomass fuels (wood, dung, and crop residues), which are typically burnt in open stoves, for cooking and sometimes heating. Such small-scale open combustion of biomass fuels results in extremely high levels of indoor air pollution, including particles; thus, on a worldwide basis, it is these populations that have the greatest exposures. It is hypothesized that high exposures to emissions from biomass cooking and heating fuels is a risk factor for low birth weight, acute respiratory infections (ARI) and other forms of ill-health in the developing world. This symposium will review recent developments in the area of cookstove intervention programs in recent past or currently ongoing – with a specific focus on investigations of adverse health effects associated with exposure to emissions from biomass cooking and reduced exposures and improved health in these settings related to newly installed replacement intervention stoves. Policy implications will also be discussed.

2009-P-582-ISES

Improved Biomass Stove (Patsari) Intervention in Rural Mexico

H. Riojas-Rodriguez,1 A. T. Marrón-Mares,1 A. Schilmann,1 I. Romieu,1 R. Pérez-Padilla,2 O. Masera,3 C. Armendariz-Arnez,3 V. Berrueta,4 C. Loreto-Gómez5; 1National Institute of Public Health, Cuernavaca, Mexico, 2National Institute of Respiratory Diseases (INER), Distrito Federal, Mexico, 3Center for Ecosystem Research, National Autonomous University of Mexico (UNAM), Morelia, Mexico, 4Group on Appropriate Rural Technology (GIRA), Morelia, Mexico, 5Comisión Federal para la Protección Contra Riesgos Sanitarios, Distrito Federal, Mexico

(15 minutes) In Mexico, one household in four still cooks with biomass fuel. One approach to reduce

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the health burden related to biomass fuel has been the provision of improved biomass stoves in rural areas of developing countries. The Patsari is a new efficient multi-pot wood-burning cook stove, which has been widely disseminated in rural Mexico. Compared to the open fires, the Patsari stove has shown in actual field conditions average reductions of 56% in household fuel consumption and 74% in greenhouse gases emissions. The median level of fine particulate matter with an aerodynamic diameter of less than 2.5 µm (PM2.5) over 48 hours in homes using an open fire were 693 µg/m3 (95% CI 246-1338) near the stove, 658 µg/m3 (67-1448) in the kitchen away from stove and 94 µg/m3 (36-236) in the patio area. Paired measurement after installation of the Patsari stove indicated a median reduction in PM2.5 concentration of 71% near the stove and 58% in the kitchen, while no change was observed in the patio area. Similar results were found for personal carbon monoxide concentrations. A randomized controlled trial was conducted in the Central Mexican state of Michoacán to evaluate the health impact of the introduction of an improved biomass stove Patsari in Mexican women. Households were randomized to receive the Patsari improved stove or keep their traditional open fire. A total of 552 women were followed with monthly visits over 10 months to assess stove use, inquire about respiratory and other symptoms and obtain lung function measurements. During follow up, adherence to the intervention was low (50%) Women who reported using the Patsari stove most of the time compared to those using the open fire had significantly lower risk of respiratory symptoms (RR 0.77, 95% CI 0.62,0.95 for cough and RR 0.29, 95% CI 0.11,0.77 for wheezing) adjusted for confounders. Similar results were found for other respiratory symptoms as well as for eye discomfort, headache and back pain. Actual use of the Patsari stove was associated with a lower forced expiratory volume in 1 second (FEV1) decline (31 mL) compared to the open fire use (62 mL) over 1 year of follow up. The magnitude of the effect on lung function was comparable to that of smoking cessation. In a subsample of participating women, the introduction of the Patsari stove significantly reduced the exposure to polycyclic aromatic hydrocarbons (PAHs) measured as the urinary metabolites of several parent compounds (42% total reduction for the sum of 10 metabolites in fresh weight concentrations). Results for a subsample of participating women showed that the biomass smoke exposure, especially carbon monoxide, had a negative effect on the heart rate variability (HRV). An increment of personal measured carbon monoxide reduced the high frequency domain of HRV (beta -0.024, 95% CI -0.041, -0.006). These results support the beneficial health effect of the improved stove and the fact that the intervention should include reinforcement and further training over the following months.

2009-P-583-ISES

Measuring Variability in Personal Exposure to Biomass Smoke with the Time-Activity and the Stove-Use Monitoring Systems (UCB-TAMS and UCB-SUMS)

I. Ruiz Mercado,1 N. L. Lam,1 A. L. Northcross,1 E. Canuz,2 S. M. Rappaport,1 K. R. Smith1; 1University of California at Berkeley, Berkeley, CA, 2Universidad del Valle de Guatemala, Guatemala City, Guatemala

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(15 minutes) The UCB-TAMS and the UCB-SUMS are two novel sensor technologies used to continuously record the time spent in the kitchen and the frequency of stove use. Both devices provide objective, accurate and unobtrusive measurements of time-activity and stove-use, enabling for the first time the precise quantification of the dynamics of such behaviors at the household- and population-level before and after the introduction of an improved cooking technology. In highland Guatemala, 80 homes in the CRECER (Chronic Respiratory Effects of Early Childhood Exposure to Respirable Matter) study using chimney woodstoves for cooking were monitored with the SUMS every other month for 28 days for 2 years. The TAMS were deployed every three months in the kitchen of 63 houses, collecting 48-hr records of minute-by-minute kitchen time-activity during 3 years using ultrasound transmitters worn by household members. At the beginning of the third year, about half of the homes received a chimney stove. Time budgets and shared time budgets across household members are presented, along with changes in the use patterns by meal, day, and season; the transitions from a open fire to a chimney stove or to their combined use; and the changes in time budgets before and after stove construction. SUMS-measured stove use rates during the first year revealed a steady decline from 90% to 80%, being overestimated by 5% by the questionnaire data. Mixed models of stove-use and time in the kitchen are built to describe the evolution of between- and within- household variances, and models of personal exposure to PM and CO are built to assess the contribution of time-activity and stove-use in the variability of personal exposure measurements.

2009-P-584-ISES

Improving Area Based Biomass Smoke Exposure Assessment With Sensor Based Time Activity Information

A. L. Northcross,1 I. Ruiz Mercado,1 E. Canuz,2 K. R. Smith1; 1University of California Berkeley, Berkeley, CA, 2Universidad del Valle de Guatemala, Ciudad de Guatemala, Guatemala

(15 minutes) Exposure assessments to air pollution typically focus on either personal or microenvironmental measurements. Personal measurements can provide more accurate individual exposures, but tend to be intrusive and expensive. Microenvironmental measurements are commonly cheaper and have more flexibility in size, number, and weight requirements of the instrumentation, but must be adjusted by time-activity information for the population of interest. Time-activity data has traditionally been difficult to obtain and imprecise using the available social-science methods or expensive with GPS and more sophisticated equipment. Deployment of new inexpensive, non-intrusive and time-activity measurement systems (TAMS), however, allows us to have the best of both worlds. In the Chronic Respiratory Effects of Early Childhood Exposure to Respirable Particulate

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Matter study being conducted in Guatemala, a low-cost personal locator carried by the participants logs the time spent in the kitchen by receiving a digital ultrasound signature unique to each person (TAMS). Here we report and compare 48-h exposure assessments based on both standard exposure assessment methods for 63 Guatemalan women (35 using chimney woodstoves and 28 using open woodfires). Personal continuous and cumulative CO measurements, and kitchen measurements of continuous and cumulative CO and PM2.5 concentrations along with time-activity monitoring was conducted. Personal CO exposures for mothers were 2.0 mg/m3 for open fire homes and 0.97 mg/m3 for chimney stove homes. Average kitchen PM2.5 concentrations were 0.90 and 0.34 mg/m3 for open fire improved stove respectively and 7.24 and 2.50 mg/m3 for CO respectively. By combining real-time CO and PM2.5 concentrations in the kitchen with the TAMS data, we can determine the daily CO exposure attributable to kitchen smoke compared to other sources and the parts of the cooking process that cause the most exposure. This work provides further validation of the value of such simple inexpensive precise sensor-based technologies for exposure assessment in remote settings.

2009-P-585-ISES

Panel Discussion: Synthesis, Research Needs, and Funding Opportunities

K. R. Smith; University of California at Berkeley, Berkeley, CA

(20 minutes) - invited panelists include: Josh Rosenthal (NIH, Fogarty Center, ITREOH Program Director, Bill Martin (NIEHS), WHO representative (15 minutes)

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Symposium

M-SY303: From Source to Biomarkers: Linking PBPK with Multimedia Fate and Exposure Models

The growing availability of biomarker data in humans opens new possibilities for intake monitoring in exposure science. However, interpreting biomarkers data and relating these data to decisions for emission reduction/exposure mitigation requires an understanding of the full continuum from source to biomarkers. This symposium addresses this challenge by exploring the various possibilities of interpreting biomarker data by coupling physiologically-based-pharmacokinetic (PBPK) models with multimedia fate and exposure models. Combining these tools potentially allows to cover the full cause-effect chain phenomena from emission to impacts, including the following mechanisms: atmospheric fate and long-range transport in the environment; partitioning of chemicals among air, soil, water and sediments; bioconcentration and bioaccumulation in the food chain; inhalation and ingestion multipathway exposures; uptake and absorption in the blood; and biokinetic and chemical partitioning in the human body. By covering the full continuum from source to dose, we address several new applications in exposure science: - Model evaluation: The serum or urine biomarkers allows the evaluation of spatially explict multimedia environmental models and intake fraction calculations. - Chemical screening and source apportionment: The coupling of multiscale multimedia environmental modeling with pharmacokinetic modeling allows screening of the chemicals with dominant impacts, carrying out a systematic source apportionment to identify critical transport pathways at local, regional and long-range scales. It constitutes the basis for the development of efficient mitigation and prevention strategies. - Pollutant fingerprinting: these approaches make possible better understanding how pollutant distributions and the fingerprint attributable to a given source emission are modified by fate, exposure and biodistribution to yield observable concentration fingerprints in environmental media, food and serum or urine. - Exposure reconstruction and biomarker interpretation: Analysis of past, present and future time trends in outdoor and indoor concentrations (e.g., household and workplace), in exposure intensity (e.g., variation in inhalation and ingestion intake with change in activity levels) and in toxicokinetics (e.g., variation in the bioelimination rate with age) enables us to reconstruct the exposure history at individual and population levels. It also allows us to interpret biomarkers using reference doses expressed in terms of blood equivalency or in term of emission equivalency. We will discuss a broad spectrum of complementary scales, from biodistribution within the human body, up to a multiscale multimedia environmental model that links a km-scale grid around point source emissions to the regional, continental and global scales. A special emphasis will be given to uncertainty and variability propagation across these different modeling steps using both Monte-Carlo and Taylor series expansion approaches. This symposium will also constitute the basis for a potential workgroup on simplified PBPK and multimedia modeling for chemical screening.

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2009-P-498-ISES

Merging Multimedia, Human Exposure and Pharmacokinetic Models for Screening Level Risk Assessments

J. Arnot; University of Toronto, Toronto, ON, Canada

Globally, it is estimated that as many as 100,000 commercial chemicals require evaluation and there are significant data gaps and limiting factors for conducting exposure and risk assessments. A screening assessment model has been developed and is described that seeks to assess and prioritize chemicals by estimating exposures to humans using available data. This RAIDAR (Risk Assessment, IDentification And Ranking) model is a coupled multimedia fate and exposure model. RAIDAR brings together information on chemical partitioning, degradation, environmental fate and transport, bioaccumulation, exposure, effect endpoint and emission rate in a coherent mass balance framework. The mechanistic structure included in the bioaccumulation and food web models demonstrates the need to quantify the effects of biomagnification and biotransformation processes on regional scale farfield dietary exposures. It is shown that biomagnification and biotransformation processes in the food web can significantly affect exposures to humans. Human body burdens can be estimated using a simple human bioaccumulation model but ultimately a more detailed pharmacokinetic model is needed, which is being developed and coupled to the RAIDAR model. This holistic framework provides a means to quantitatively evaluate the propagation of uncertainty of model inputs such as biotransformation rates on human exposure estimates. The farfield exposure estimates are detailed as case studies for selected chemicals (PBDE-99, HCB). The large-scale application of the model for ranking chemicals based on the potential for human exposure is also illustrated.

2009-P-501-ISES

From Emission to Population Blood Concentration of Dioxin-like Compounds and PBDEs

O. Jolliet; University of Michigan, Ann Arbor, MI

This paper aims to explore and better understand the source-to-body fate, exposure and body distribution of dioxin-like compounds and polybrominated diphenyl ethers (PBDEs). The idea is to couple a spatially differentiated multimedia fate and exposure models with physiologically-based pharmacokinetic (PBPK) models for humans to quantitatively predict variations in body burden as a function of sources, exposure history and personal characteristics. For fate and exposure, the intake fractions – the fraction of an emission taken in by a population - were calculated for 830 cells using the North American IMPACT model. In the case of emissions to air, this resulted in dominant

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intake through meat, dairy products and cereals. Intake fractions by inhalation are in general three orders of magnitude lower than by ingestion. In agreement with the two-film theory that predicts a lower chemical absorption and transfer into the food chain at very high log(Kow), the total intake fraction declines as the log(Kow) increases up to 8.7 in Deca-BDE. For BDE-209, ingestion in food is mainly due to a limited number of point atmospheric sources that dominate overall emissions in North America. A simple toxico-kinetic model was built using apparent half-lives (Milbrath et al., 2009 – EHP) and total body fat. The University of Michigan Dioxin Exposure Study provided a unique opportunity to evaluate the PBPK predicted changes in serum TCDD levels in individuals born between 1900 and 1985: the PBPK model is indeed able to reflect the increase in TCDD concentration with age and explains up to 42% of the serum variability. The combination of this toxicokinetic model with a multiscale multimedia version of the IMPACT model model enables us to link point source emissions to serum concentrations, from a km-scale around the source to the regional, continental and global scales.

2009-P-502-ISES

Use of Biomonitoring and Pharmacokinetic Data to Inform Multimedia Fate and Exposure Models - Examples and Data Needs

L. L. Aylward; Summit Toxicology, Falls Church, VA

The collection of population-based biomonitoring data across a broad range of chemical classes by the National Health and Nutrition Examination Survey (NHANES) allows use of such data in efforts to model the continuum from source to exposure. If an assumption of pseudo-steady-state exposures is made, these data can be used to estimate a central tendency of exposures across the population. For compounds that are excreted principally via the urinary pathway, urinary concentration data can be used to back-estimate exposures (regardless of source) based on a mass balance approach if estimates of urinary excretion fraction are available. For compounds that are monitored in blood, simple pharmacokinetic evaluations using estimates of volume of distribution and elimination rate allow estimates of average intake or exposure rates corresponding to the measured blood concentrations. We will present examples based on phthalates demonstrating the use of basic pharmacokinetic data to estimate central tendencies of exposure rates, as well as factors contributing to uncertainties in those estimates. We also present an evaluation relating blood concentrations of volatile organic compounds to external exposure levels. We will discuss the chemical-specific factors that influence the key parameters and the types of data that may be available to inform such estimates across the categories of chemicals in the NHANES survey. Estimates of intake based on such approaches can be used to evaluate the output from the source-to-exposure continuum modeling efforts discussed by other presenters in this section, and this information can be used to refine those models.

2009-P-503-ISES

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Evaluation of Multimedia Fate and Exposure Models Using PAH Biomarker Data

T. E. McKone; Lawrence Berkeley National Laboratory, Berkeley, CA

Recent advances in three often unrelated fields provide an opportunity to evaluate multi-media fate and exposure modeling principles for a number of organic chemicals. These advances include 1) new insights on how food and the indoor environment act as sources, reservoirs, and reaction sites for pervasive organic chemcials, 2) a rapidly expanding national and state database of measured tissue residues, and 3) exposure surveys that provide useful but incomplete data on links between tissue levels and chemical loads in food, air, and residences. Biomarkers have proved useful for assessing human exposure. But most substances taken into the human body are biotransformed through metabolism and excreted in urine as different substances. Efforts to use biomonitoring to assess the magnitude, source, and pathway of exposure to a particular pollutant must account for internal transformation to relate metabolism products in urine to parent compound intake. In this paper we evaluate the use of internally transformed chemicals to assess the source and magnitude of human exposures through food and residential pathways to polycyclic aromatic hydrocarbons (PAHs). Our results show that, in spite of significant model and emissions uncertainties, the combination of models, biomonitoring data, and environmental data show consistent trends and explanations for intake/emissions ratios for PAHs. Future work must focus on how well modeled results can capture variability in the biomonitoring data and internal transformation.

2009-P-505-ISES

Linking Exposure and Biomonitoring Data Using Pharmacokinetic Models

C. Tan; The Hamner Institutes for Health Sciences, Center for Human Health Assessment, Research Triangle Park, NC

Biomonitoring data are measures of internal doses, but they do not have a direct relationship with exposure or effects. They are complexly related to the nature of exposures and the mechanisms of clearance of a substance from the body. Especially with population-based biomonitoring studies, measured biomarker levels may reflect recent exposure, exposure over a longer period of time, or neither. Linking biomonitoring data to exposures requires information on the pharmacokinetics of the substance, as well as the time-dependent nature of the exposure in relation to time of sampling. In this presentation, two examples will be used to demonstrate the capability of pharmacokinetic models to interpret biomonitoring data by linking them to external exposures. In the first example, a physiologically based pharmacokinetic model is used to estimate chloroform concentrations in tap water that would be consistent with the measured chloroform concentrations in blood. In the second example, a 2-compartment pharmacokinetic model for bisphenol A is used to examine the impact of time between exposure and sampling on bisphenol A concentrations in urine.

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2009-P-506-ISES

Development of a Simple Pharmacokinetic Model to Predict Concentrations of Di-n-Butylphthalate (DnBP) Metabolites in Blood and Urine in Humans

M. Lorber; US-EPA, Research Triangle Park, NC

A simple pharmacokinetic model is developed to predict the blood and urine concentrations of key metabolites of Di-n-butylphthalate (DnBP), based on data from an individual who self-dosed D4-labelled DnBP at 5.38 mg. Four labeled metabolites were monitored in blood in urine: blood in 6 measurements within about 7 hours (the first at 30 min., the second at 65 min., and so on), and in urine with every void over 48 hours. DnBP is modeled to metabolize first to mono-n-butyl phthalate (MnBP), and then to both 3-hydroxy-mono-n-butylphthalate (3OH-MnBP) and 4-hydroxy-mono-n-butylphthalate (4OH-MnBP) and finally to to 3-carboxy-mono-propylphthalate (3cx-MPP -not found in blood or urine). The model begins with a dose supplied to a “volume of distribution” in blood, Vd (in units of mL/kg BW), which ultimately is a calibrated model parameter. Metabolism in the pathways described is assumed to occur in this blood reservoir. Rates of transformation dictate the disappearance of DnBP and the (dis)appearance of subsequent metabolites, and additional removal rates dictate the transfer of metabolite from the blood reservoir to the “bladder” reservoir. There, metabolites build up until a void, and then all of the metabolite in the bladder reservoir is mixed in a volume of urine. The model was calibrated using measured blood concentrations, urine volumes, times of void, and concentrations from the single self-dosed individual. The blood concentrations served to calibrate the rates of transformation and removal (to the bladder) as well as the VD, a constant value which was applied to all metabolites. The data as well as the model showed a capture of nearly 100% of molar DnBP as metabolites in the urine in the 20 void events after 48 hours. As an example of the elevation of MnBP in this person’s blood, the concentration in the first few urination events was about 10 mg/L, which is 3 orders of magnitude higher than levels of about 10 µg/L found in the general US population (NHANES).

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Platform

M-PL301: Exposure Assessment in Minnesota

2009-A-311-ISES

A Model For Multi-pathway Risks From Air Pollution: Comparison Of Point Source Modeled Risk Results With Refined Facility-specific Risk Assessments

K. Ellickson,1 G. Pratt,1 M. Dymond,1 J. The'2; 1Minnesota Pollution Control Agency, St. Paul, MN, 2The Lakes Environmental Software, Waterloo, ON, Canada

A modeling tool (MNRiskS, Minnesota Risk Screening) was developed for estimating the potential human health impacts from 203 air pollutants with both emissions and toxicity data from all inventoried sources, including point, mobile, and non-point or area sources. The tool uses pollutant emissions inventory data to model air concentrations, deposition, movement in environmental media and potential exposure through several scenarios. The spatial scale of the model extends from a neighborhood to the statewide scale (Minnesota). Summed risk results from MNRiskS were compared with results from risks assessed under the regulatory auspices of the state of Minnesota. Risk assessments are conducted within Minnesota’s regulatory framework to address questions pertaining to potential human health risks from air emissions sources for air permitting or environmental review. These risk assessments, or the Air Emissions Risk Analysis process (AERA), are conducted generally for large point sources. Risk results from the AERA process were standardized to the emissions used in the MNRiskS model before any statistical or direct comparisons were made. Statistical associations between MNRiskS and AERA results for ~ 10 facilities for non-cancer and cancer health endpoints and from indirect and direct pathways were tested and discussed. The results from the two risk assessment processes were compared in the context of pathway (inhalation, ingestion), sector (coal, waste combustion, specialty chemical, etc.) and health endpoint (non-cancer, cancer). In brief summation, the results from the two risk model methodologies were significantly statistically correlated, however MNRiskS risk results were lower than the final risks estimated within the AERA process for the majority of the facilities and pathways. The description of the MNRiskS tool, comparisons of MNRiskS air concentrations results with monitored data and presentation of overall risks results are presented in a separate abstract.

2009-A-316-ISES

A Comprehensive Model For Multi-pathway Risks From Air Pollution: Overview Of Results And Validation

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G. C. Pratt,1 M. Dymond,1 K. Ellickson,1 J. The2; 1Minnesota Pollution Control Agency, St Paul, MN, 2Lakes Environmental Software, Waterloo, ON, Canada

A tool (called MNRiskS for Minnesota Risk Screening) was developed for modeling the potential human health impacts of air pollution from 203 pollutants with both emissions data and toxicity data that are emitted from all inventoried sources, including point sources, mobile sources, and non-point or area sources. The tool uses pollutant emissions inventory data to model air concentrations, deposition, movement in environmental media, and potential exposure through several scenarios. It covers the geographic scale from a neighborhood to an entire US state (Minnesota), and can be used to identify pollutants, pathways, geographic areas, sources, and receptors of potential concern. Fish consumption, followed by dairy consumption and inhalation were the pathways in which the highest estimated cancer risks were found, and fish consumption, followed by inhalation and drinking water ingestion were the pathways with the highest non-cancer hazard indices. Dioxin and dioxin-like compounds created the highest estimated cancer risks, and acrolein and diesel particles created the highest estimated non-cancer hazard indices. Validation studies were done comparing the modeled air concentrations with measured values and by comparing estimated facility risks with more refined risk assessments done in regulatory processes. The model-monitor comparisons showed a general underestimation of air concentrations and room for improvement in model estimation, shortcomings that were attributed to deficiencies in the emissions inventory. Comparisons of MNRiskS results with more refined risk assessments are presented in a separate abstract.

2009-A-470-ISES

New Intake Rates Lead To Key Changes In Minnesota Groundwater Regulatory Standards

P. Moyer, H. Goeden, I. Hassan, C. Greene; Minnesota Department of Health, St. Paul, MN

The Minnesota Department of Health (MDH) protects public health by establishing Health Risk Limits (HRLs) for contaminants found in drinking water. An HRL, expressed in units of ug/L, is the concentration of a contaminant in groundwater that is without appreciable risk to human health. Recent revisions to the HRL methodology included the pairing of data-derived, life-stage specific water intake rates with the appropriate duration of exposure to groundwater contaminants. This approach ensures that susceptible populations (e.g. pregnant women, infants, and children) are considered and protected from adverse health effects. The new default intake rates are calculated to be 0.289 L/kg-day for the acute and short term durations (one day and up to 30 days respectively), 0.077 L/kg-day for the subchronic duration (up to 10% of a lifetime (~7-8 years in humans)), and 0.043 L/kg-day for the chronic duration (greater than 10% of a lifetime). Using these 95th percentile time-weighted-average intake rates ensures that MDH values afford the protection required by Minnesota statutes. In contrast, the old

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methodology for deriving HRLs relied on the adult only chronic default intake rate of 0.029 L/kg-day (i.e. 2 L/70 kg-day). This default value underestimates the actual rate of exposure for all durations, resulting in less protective standards, particularly for infants and small children. Combining these new intake rates with the appropriate age and duration specific toxicity values results in a more comprehensive risk assessment than had been conducted in the past. MDH adopted the new intake rates after finding that standards based only on chronic assessments may not be protective of less-than-chronic exposures. While this new process reflects an improvement in assessing risk, additional data and modeling of life-stage intake rates would continue to enhance and refine these results. Examples of evaluations for perfluorobutyrate (PFBA), benzene, and acetochlor will be presented.

2009-A-239-ISES

Historical Exposure Reconstruction In The Taconite Mining Industry - Study Design

J. Hwang, G. Ramachandran, P. C. Raynor, B. Alexander, J. H. Mandel; University of Minnesota, Minneapolis, MN

The goal of this study is to assess historical and current exposures of workers to asbestos and non-asbestos fibers, respirable-dust, and respirable-silica for an epidemiological study on the relationship with mesothelioma and silicosis in the taconite industry from 1955- 2008. Exposure histories will be evaluated for a cohort of workers selected from three mining companies in north-eastern Minnesota. Historical exposure data are available from the Mine Safety and Health Administration, and internal databases from the mining companies including impinger, personal gravimetric, and area gravimetric measurements. The exposure data matrix will have dimensions of year, job title, task, job location, duration of shift, and type of process. We expect that monitoring data will be missing for substantial portions of the matrix. To fill in missing data, we will use information on historical exposure determinants like ventilation and generation rates using exposure models. Interviews with veteran workers will help provide information on historical working conditions. Several statistical imputation methods will be used. For fibers, exposure metrics will be considered including the count of long and short fibers, NIOSH 7400 fibers, and fiber surface area. An assessment of current exposures including personal measurements of asbestos and silica exposures and particle size distributions based on cascade impactor data will be used to provide a benchmark from which past exposures can be extrapolated. A Bayesian framework will be used to combine monitoring data with modeling predictions and expert judgments. While Similar Exposure Groups will be created on the basis of historical and current personal measurements, we collected real-time area measurements of respirable particle concentrations in mining, crushing, concentrating, and pelletizing areas. At the pellet-feed into furnace, the respirable-dust concentration of particles was 11 times higher than other stages of processes. The particle surface area in the pelletizing area was 5 times higher than others.

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2009-A-460-ISES

Tracking Progress And Measuring The Impacts Of Particulate Matter Reduction Strategies In Minnesota

J. E. Johnson,1 G. Pratt,2 P. Lindgren,1 C. Stroebel,1 A. Williams,1 M. McCourtney2; 1Minnesota Department of Health, St. Paul, MN, 2Minnesota Pollution Control Agency, St. Paul, MN

We report on a project to develop and evaluate a set of environmental health outcome indicators for tracking the public health impacts of particulate matter (PM) emissions reduction initiatives over a 10-year period, 2000-2009 in two study areas: the Minneapolis-St. Paul metropolitan area and Olmsted County, Minnesota. Among a wide range of national and local PM emissions reduction initiatives currently being implemented is the Minnesota Emissions Reduction Project (MERP). MERP is a voluntary $1 billion energy project that includes the conversion of two coal-fired power plants to natural gas, and the installation of new control equipment on a third plant. Indicator development began with the collection of existing environmental monitoring, modeling, and public health surveillance data followed by statistical analyses of data linkages. PM monitoring data extracted from the EPA AQS were examined for interpretation issues. PM concentrations measured across FRM monitors in the area from 2000-2006 showed little geographic variation such that spatial interpolation was unlikely to improve the exposure estimate. The Comprehensive Air Quality Model with Extensions (CAMx) version 4.51 for model year 2005 was used to improve spatial and temporal data coverage. Daily undulations of model data follow monitored data quite well. Data limitations with respect to missing data, spatial applicability, and data collection frequency are described. Daily maximum PM measurements from continuous monitoring data were compared to Heirarchical Bayesian modeled data. Traffic exposure was evaluated as a temporal invariate. Annual average traffic count data was used to calculate average daily vehicle miles traveled within each zipcode. The evaluation of these data sources as population exposure indicators and for import into a data linkage with health outcomes is described.

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Platform

M-PL302: Exposure and Vulnerable Groups

2009-A-228-ISES

Correlations Among Psychosocial And Indoor Physical Environmental Exposures In An Urban Pregnancy Cohort: Project Access

J. L. Peters,1 J. I. Levy,1 S. Franco Suglia,1 M. Sandel,2 D. R. Gold,3 M. Sternthal,1 R. J. Wright3; 1Harvard School of Public Health, Boston, MA, 2Boston Medical Center, Boston University School of Medicine, Boston, MA, 3Harvard School of Public Health and The Channing Laboratory, Brigham and Women's Hospital, Harvard Medical School, Boston, MA

Background and Objective: Given documentation of synergistic effects of multi-faceted exposures on health, understanding how social and physical environmental toxins co-vary in high-risk populations (i.e., those living in low-income urban communities) may help explain respiratory health disparities. Within the Asthma Coalition on Community, Environment, and Social Stress (ACCESS) project, a prospective study of prenatal and early life exposures on urban asthma risk, we examined correlations among socio-demographics (race/ethnicity and education), and prenatal exposures to allergens (cockroach, dust mite, and mouse allergens), modeled indoor levels of air pollutants (nitrogen dioxide [NO2], fine particulate matter [PM2.5], and elemental carbon [EC]), and psychological stress (number of urban life stressors and measure of neighborhood safety [Crisis in Family Systems], and measure of financial strain). Method: Spearman correlations and bivariate analyses were used to evaluate the tendency of these variables to co-occur. Analyses focused on 315 mothers (55% Hispanics, 24% Black, and 21% mixed/other) with complete data for all stressors. Results: Hispanic populations had significantly greater exposure to cockroach allergen (p=0.01) and EC (p<0.001), while African-Americans had significantly greater exposure to EC (p=0.01). Lower maternal education was positively associated with exposures to cockroach allergen (p=0.01), NO2 (p=0.05), PM2.5 (p=0.003), and EC (p<0.001). Mouse allergen was positively associated with cockroach allergen (p=0.001), NO2 (p=0.04), PM2.5 (p=0.01), number of life events (p=0.002), and financial strain (p=0.01). Cockroach allergen was positively correlated with EC (p=0.06) and dust mite allergen was negatively associated with the number of life events (p=0.01) and neighborhood safety (<0.001). Conclusion: We demonstrate co-relation across social and physical environmental exposures in this urban, ethnically diverse cohort with different associations with race/ethnicity and education. Examining the independent and interactive effects of combined exposures as we follow these children for the development of asthma and other atopic disorders may more completely inform respiratory health risk.

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2009-A-335-ISES

Cadmium Body Burdon And Erythrocyte Parameters In An Industrisal Area Of Taiwan

H. Y. Chen,1 J. W. Chen,1 M. H. Yang,2 S. L. Wang1; 1National Health Research Institutes, Miaoli, Taiwan, 2National Tsing Hua University, Hsinchu, Taiwan

Patients with Itai-itai disease from cadmium (Cd) poisoning had hypoproduction of erythropoietin. Previous studies suggested a close correlation between renal tubular dysfunction and anemia. Anemia is associated with heavy metal (Cd and lead) and some trace elements (iron, zinc, copper). It can occur either because of the increased destruction of erythrocytes or from their loss and/or insufficient production. Cd is a toxic heavy metal that can induce renal tubular dysfunction after long-term accumulation in the kidney. We aimed at assessing cadmium body burden, its expose factors, and anemia in an environmentally high exposure area of Taiwan. A total of 649 subjects were randomly sampled from age (35-64 years) and gender stratified population during 2002-2003. Geometric means of blood cadmium (B-Cd) concentrations for man and women were 1.48 and 1.28μg/l, respectively. B-Cd levels increased with increasing of cigarettes smoked in men. In women, increased B-Cd concentrations was associated with the number of red blood cells (RBC) (p<0.01) and decreased concentration of mean corpuscular hemoglobin (MCH) (p<0.1), and mean corpuscular hemoglobin concentration (MCHC) (p<0.01). In women, we decreased found lower level of β2-microglobulin (B2MG), the risk for anemia increased around 4 folds with B-Cd over the median of 80.1μg/l as compared to the less group. Odds ratio for anemia raise to 5.14 (p<0.05) when B-Cd concentrations and β2-microglobulin both larger than median of 1.26 μg/l and 80.1μg/l, respectively. Women appeared to have adverse erythrocyte effects though with slightly lower cadmium level as compared to men. Cd might induce anemia through the direct injury of the proximal renal tubular cells that are responsible for erythropoietin (Epo) production. Further animal experiments were suggested for delineating Cd associated with erythrocyte hypoxaemia. Keywords: Cadmium, Erythrocyte Parameters, Anemia, β2-microglobulin

2009-A-382-ISES

Lead, Cadmium, And Arsenic Levels In Meconium From Infants Born Near A Mining-related Superfund Site

R. A. Lincoln,1 C. Amarasiriwardena,2 A. Ettinger,1 J. Shine,1 R. O. Wright,3 J. D. Spengler1; 1Harvard School of Public Health, Department of Environmental Health, Boston, MA, 2Channing Laboratory, Brigham and Women's Hospital, Boston, MA, 3Children's Hospital, Department of Medicine, Boston, MA

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Meconium, the initial stool of a newborn, accumulates from the 2nd trimester onwards, and may be useful in reconstructing exposure during specific periods of gestation, since meconium produced earlier in pregnancy is excreted earliest in the postnatal period. Serial meconium samples collected after birth may therefore provide a record of changes in maternal exposure, maternal-fetal transfer, and/or fetal excretion. We collected all meconium produced within the first 48 hours after birth from infants born near the Tar Creek Superfund Site (Oklahoma), an area contaminated by metals mining waste. Samples were collected from each infant on cotton pads placed inside the diaper and frozen after collection. Frozen samples were removed from the diapers, lyophilized, homogenized, microwave digested with nitric acid, and analyzed for lead, cadmium, and arsenic using dynamic reaction cell-inductively coupled plasma-mass spectrometry (DRC-ICP-MS). Linear mixed effects models were used to assess changes in metals concentrations against the time of sample collection. Thirty-two samples were collected from 10 infants; each infant produced between 2 and 6 samples. Seventy-eight percent showed detectable levels of lead (mean concentration: 18.0 ng/g), and 84% showed detectable levels of arsenic (mean concentration: 34.7 ng/g). All samples were below the limit of detection for cadmium (LOD=2.8 ng/g). Meconium concentrations for lead and arsenic, respectively, increased at a rate of 1.2 ng/g (Pb: p=0.009) and 1.0 ng/g (As: p=0.07) for each hour postpartum that the diaper was collected. Our analysis of serial meconium samples suggests that changes in maternal exposure, maternal-fetal transfer, or varying fetal excretion rates (possibly due to rapid fetal growth in the third trimester) over the course of pregnancy may be reflected in meconium metals concentrations. Meconium is an emerging and potentially useful biomarker for prenatal exposures to environmental contaminants. Further study is needed to thoroughly investigate changes in meconium contaminant concentrations over time.

2009-A-300-ISES

Perchlorate Exposure And Dose Estimates For Infants

B. Blount,1 L. Valentin-Blasini,2 Y. Cao,3 J. Bernbaum,4 S. Otero-Santos,2 W. Rogan3; 1Centers for Disease Control and Prevention, Suwanee, GA, 2Centers for Disease Control and Prevention, Atlanta, GA, 3NIEHS, RTP, NC, 4Children’s Hospital of Philadelphia, Philadelphia, PA

Perchlorate exposure is of health concern because perchlorate can modify thyroid function by competitively inhibiting iodide uptake. Infants may have higher perchlorate exposure compared with adults because of active perchlorate transport into milk. Therefore, we measured perchlorate and related anions (nitrate, thiocyanate and iodide) in 206 urine samples from 92 infants (ages 1-377 days). Geometric means for perchlorate, nitrate, thiocyanate and iodide in infant urine samples were: 1.22, 12199, 63.5 and 127.4µg/L, respectively. Perchlorate exposure doses were estimated for each infant at each sampling time. The mean exposure dose was 0.349 µg/Kg/day, with 15% of the estimated doses exceeding the EPA reference dose of 0.7 µg/Kg/day. The

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magnitude of perchlorate exposure dose was correlated with feeding method: breast fed infants had higher perchlorate exposure dose (mean 0.614 µg/Kg/day) compared with cow milk-based formula (mean 0.204 µg/Kg/day, p < 0.0001) and soy-based formula (mean 0.066µg/Kg/day, p < 0.0001). High intra-individual variability (mean coefficient of variation of 74%) was observed for infants who provided multiple samples (2 or more) over a 12-month period. Our results indicate that infants likely have higher perchlorate exposure doses compared with adults.

2009-A-310-ISES

Pesticides And PCBs Detected In The Milk Of Women Residing In Urban And Rural Communities Of California

R. H. Weldon,1 M. D. Davis,2 D. B. Barr,2 A. Bradman,1 N. Holland,1 B. Eskenazi1; 1Center for Children's Environmental Health Research, School of Public Health, University of California, Berkeley, CA, 2National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA

Background: Maternal concentrations of persistent pesticides and PCBs have been monitored worldwide in various tissues over the past several decades. Policy efforts have led to declining biological concentrations of these chemicals; however, few publications have reported lactational concentrations of these persistent organic pollutants (POPs) in women from the United States since the 1980’s. Furthermore, no studies have reported detection of non-persistent pesticides such as chlorpyrifos in the milk of women residing in the United States despite concerns about their effects on child neurodevelopment. Methods: We measured concentrations of 8 organochlorines, 14 contemporary-use non-persistent pesticides, and 4 PCB congeners in breastmilk samples from two groups of women residing in the agricultural region of Salinas, California (CHAMACOS n=60, Peripartum Excretion Study (PES) n=13) and one group of women residing in the urban city, Berkeley, CA (n=22). Samples were collected from 1999-2006. Results: Detection frequencies were >90% in all three populations for chlorpyrifos, hexachlorobenzene, β-hexachlorocyclohexane, o,p’- and p,p’-DDT/DDE, chlorthal-dimethyl, and PCBs 118, 138, and 153. In general, detection frequencies were between 10 and 50% for phosmet, cyfluthrin, atrazine, propoxur, and chlorpyrifos-methyl, and <10% for cypermethrin, fonofos, disulfoton, deltramethrin, methoxychlor, bendiocarb and diazinon. Chlorpyrifos geometric mean concentrations were 28, 24, and 53pg/g milk and p,p’-DDE geometric mean concentrations were 4004, 8473, and 5676pg/g milk for Berkeley, CHAMACOS, and PES women, respectively. Conclusion: Preliminary results indicate that POPs such as organochlorine pesticides and PCBs remain detectable in the milk of women residing in the United States. In addition, several non-persistent pesticides used in agriculture and/or the home were detectable in human milk, indicating the potential for direct exposures to neonates and young children. Chlorpyrifos, which was banned for residential use in 2000, was detected in urban women at concentrations comparable to women residing in Salinas, a region with heavy agricultural use of this pesticide.

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Tuesday, November 03, 2009

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Symposium

T-SY101: Old vs. New Persistent Organic Pollutants (POPs) - Some Exposure Surprises

Persistent organic pollutants, or POPs, have come to be of increasing concern among the public and scientists. These synthetic pollutants are characterized as being very persistent in biota and the environment, toxic, undergoing trans-boundary migration, and bioaccumulative. Legacy or classical POPs include PCBs, organochlorine pesticides, and dioxins/furans. Current interest includes newly emerging POPs such as brominated flame retardants, (including polybrominated diphenyl ethers), and polyfluorinated alkyl chemicals (including PFOS and PFOA). Because of tremendous improvements in analytical chemistry, the detection of these compounds in the environment and in humans has been cause for some concern. Important questions regarding these compounds e at this time include exposure assessment, toxicity, possible substitutes, and regulations. This symposium will provide a current overview and detail recent findings from scientists actively researching these compounds. An overview and a summary will be provided by Linda Birnbaum, Director, NIEHS/NIH, a senior research scientist in the POPs arena.

2009-P-120-ISES

Old vs. New POPs-(OVERVIEW) - Some Exposure Surprises

L. Birnbaum; National Institute of Environmental Health Sciences/National Toxicology Program, Research Triangle Park, NC

Organochlorine Pesticides, Dioxins, and PCBs are all legacy POPs. In most cases, their production and use has either been totally phased out or severely restricted. Exposure to these classes of chemicals is largely via microcontamination of the food supply due to the persistent nature of these compounds, and their bioaccumulation and biomagnifications up the food chain. They are largely present in lipid rich foods of animal origin. In contrast, emerging POPs of concern involve several classes of brominated flame retardants and perfluorinated chemicals such as the long chain polyfluorinated carboxylic or sulphonic acids, exemplified by PFOA and PFOS. These are all present in consumer products, which leads to exposure via inhalation and ingestion of house and office dusts as significant pathways of exposure. Also, while the lower brominated PBDEs are highly lipophilic and partition into fat tissue, the highly brominated congeners, such as the nona- and deca-BDEs, tend to be found in blood or liver, rather than in adipose tissue or lipid. This is also true of the PFCs which also fail to partition into fat. Thus, exposure to these newer POPs involves other exposure sources than primarily fatty foods of animal origin. (This abstract does not reflect the policy of NIEHS.)

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2009-P-121-ISES

Are Some Non-POPs Really POPs?

L. Needham; Centers for Disease Control and Prevention, Atlanta, GA

The term "persistent organic pollutants" can apply to the legacy POPs as well as selected emerging POPs. Although many so-called "environmental chemicals" are nonpersistent in the environment and in people, a small portion of each dose may be stored in the body, which allows that chemical to be continuously released into the bloodstream and potentially travel to a target organ. Therefore, although these chemicals are not "persistent" according to the definition, they are found in various biological specimens, such as adipose tissue and milk, and constantly have access to the bloodstream. These chemicals include chlorpyrifos and bisphenol A. This talk will focus on these and other nonpersistent chemicals and how they can be considered as “persistently” present in the body.

2009-P-122-ISES

Polyfluoroalkyl Chemicals in Humans - Distributions and Trends

A. Calafat; Division of Laboratory Sciences, National Center for Environmental Health, Centers for Disease Control and Prevention, Atlanta, GA

We will discuss the usefulness of biomonitoring programs, using the U.S. National Health and Nutrition Examination Survey (NHANES) as an example, to provide indisputable evidence of exposure and absorption of polyfluoroalkyl compounds (PFCs) in humans, of demographic differences in human exposures, and to assess temporal changes in internal dose when actions are taken that lead to changes in the environmental concentrations of PFCs.

2009-P-123-ISES

PBDEs in US Food

A. Schecter; University of Texas School of Public Health at Dallas, Dallas, TX

We previously found that levels of polybrominated diphenyl ethers (PBDEs) in blood and breast milk of people from the US are the highest in the world. Previous US market basket surveys found that levels of PBDEs were highest in fish, then meat, then dairy products, with food derived from fruit and vegetables having the lowest levels. Here we will report findings from our newest market basket survey- a sampling of 30 different food items from 3 disparate US locations: Albany, New York; Dallas, Texas; and Los

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Angeles, California. We found no significant difference in the overall total PBDE levels in any of the three locations. Compared to the previous study, in this study total PBDE levels were higher in meat products than in fish, and levels in dairy foods were significantly higher than previously measured. Additionally, PBDE levels in commonly consumed foods such as eggs, margarine, and vegetable based oils were higher than previously measured, although not statistically significantly higher due to small sample size.

2009-P-124-ISES

Fate and Metabolism of PBDEs in Mammalian Systems

H. Hakk; United States Department of Agriculture - Agricultural Research Service, Fargo, ND

Polybrominated diphenyl ethers (PBDEs) belong to an emerging class of persistent organic pollutants (POPs). Although the toxicology of PBDEs is not well developed, they are persistent and bioaccumulative, and therefore, of growing environmental concern. The metabolism of PBDEs in mammalian systems has been investigated, and although differences among individual congeners exist, demonstrates that PBDEs are well absorbed, deposit in lipophilic tissues, are poorly metabolized, bind readily to fecal macromolecules, and undergo similar pathways of metabolism. The exception is the fully brominated decaBDE, which demonstrated a high degree of metabolism, and the results provided a mechanism to explain the production of lower brominated congeners via debromination. PBDEs administered in either dust or oil vehicle showed that PBDEs in dust were as bioavailable as those dissolved in an oil vehicle, and that higher brominated congeners were less bioavailable than lower brominated congeners. The results support the hypothesis that, in addition to foods, ingested dust can be a source of PBDEs exposure in humans. The scope of our research highlights a difference between the pharmacokinetics of legacy and emerging POPs.

2009-P-125-ISES

PBDEs & Other Flame Retardants in Indoor Environments: Exposure from Homes, Offices and Cars

T. Webster; Boston University School of Public Health, Boston, MA

Exposure to PBDEs in North America is thought to take place primarily via inadvertent dust ingestion and other pathways of the indoor environment. While the brominated flame retardant (BFR) content of house dust has received some attention, very little information is available on offices and cars, two other microenvironments of potentially great importance. Our paper compares BFR levels in dust we sampled using similar methods from homes, offices and cars and discusses the implications for human

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exposure. Air samples are compared with those previously collected from homes using similar methods.

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Symposium

T-SY102: Semivolatile Contaminants Indoors: Advances in Environmental Chemistry and Human Exposure Assessment

This symposium will explore how more detailed knowledge of indoor chemistry and exposure can be obtained by combining laboratory experiments, field measurements, biomonitoring data, and chemical mass balance models. Health research agencies continue to estimate residential exposures by combining sparse concentration data with detailed time-activity-based models using assumptions about dermal loading, hand-to-mouth transfers, and uptake rates. Recent studies of farm-worker health in the Salinas Valley reveal the importance of the indoor environment for exposure to outdoor chemicals. Urine samples from 600 subjects revealed that both the buildings and the occupants were acting as chemical receptors for substances that originated outdoors. This work highlighted the importance of the indoor environment as an integrator and delivery system for environmental pollutants, particularly for the semivolatile organic chemicals. However, indoor pollutants come from a number of sources including outdoor air, water supplies, vapor intrusion from subsurface soil, tracked-in soil, and from numerous indoor sources such as solvents, fragrances, flame retardants, building materials, electronic equipment, pesticides, stain repellants, plastics, etc. Many of these pollutants are expected to be strongly influence by indoor environmental chemistry or “chemodynamics”. This symposium will address the need to better understand not only the sources of chemicals indoors but also their transport, partitioning and persistence in the indoor environment. Our goal is to provide a more systematic understanding of the relationships among indoor contaminants, indoor chemistry, human exposure, and tissue burden by considering three basic elements. The first element includes measurements and indoor mass-balance models that provide a repository of experimental evidence to address both the chemical behavior of contaminants and how the indoor levels influence chemical uptake into the occupants. The second element is an expansion of our ability to use pharmacokinetic (PK) models to relate chemical uptake to biomonitoring data (urine and blood levels). The final element is the use of statistical and modeling tools such as Bayesian melding to organize this information in a form that is useful to health scientists providing a means to prioritize critical information needs. We will include time for a panel/audience discussion.

2009-P-85-ISES

How the Indoor Environment Traps and Delivers Semi-Volatile Compounds to its Occupants

J. C. Little,1 C. Weschler,2 W. W. Nazaroff,3 H. Levin4; 1Civil and Environmental Engineering, Virginia Tech, Blacksburg, VA, 2Environmental and Occupational Health

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Sciences Institute, University of Medicine and Dentistry of New Jersey and Rutgers University, Piscataway, NJ, 3Department of Civil and Environmental Engineering, University of California, Berkeley, CA, 4Building Ecology Research Group, Santa Cruz, CA

It is widely recognized that high indoor exposures can result from limited air exchange or ventilation, but it is also important to understand the role of indoor reservoirs and surfaces in emitting, retaining and re-emitting a range of pollutants. This presentation reviews and evaluates our current understanding of how the indoor environment releases, captures and re-emits semivolatile pollutants and how this relates to human exposure.

2009-P-91-ISES

Tracking Emissions from Indoor Sources to Tissues Using Fugacity Mass Balance Models

J. Arnot,1 D. Mackay,2 E. Webster,2 F. Wania1; 1University of Toronto at Scarborough, Toronto, ON, Canada, 2The Canadian Centre for Environmental Modelling and Chemistry, Trent University, Peterborough, ON, Canada

Fugacity is a measure of the tendency or pressure exerted by a chemical to leave a compartment and is essentially equal to partial pressure. It is a well-accepted modeling approach for performing chemical mass balance in multicompartment outdoor and indoor environmental models and to bioaccumulation and food web models. It has also been successfully applied to physiologically based pharmacokinetic (PBPK) models. We discuss first the use of fugacity models and physico-chemical properties to determine the indoor fate and concentrations of chemicals and the resulting transient or steady-state human exposures. We then describe PBPK models also using fugacity that can be used to predict and interpret tissue concentrations resulting from these exposures. Since tissue levels for most organic chemicals will also include farfield sources (e.g. dietary and outdoor exposures) it is necessary to quantify the contribution of these exposures in comparison to those from the indoor environment. Finally, we discuss the merits of combining the indoor and PBPK fugacity models to provide a seamless account of the sources, transport and transformation of chemicals as they migrate from sources through the indoor environment to human tissues. An advantage of fugacity is that all concentration levels are presented in identical units, as well as in conventional units, thus facilitating interpretation of the predictions and evaluation of the consistency of model estimates with monitoring data. Examples are given from an ongoing study of exposure to drinking water contaminants and pesticides and solvents used indoors.

2009-P-89-ISES

Indoor Environmental Samples for Biomonitoring

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R. L. Maddalena; Lawrence Berkeley National Laboratory, Berkeley, CA

Indoor environmental sampling data for SVOCs remain sparse relative to other contaminant classes. This presentation will explore the relevance of sampling techniques to emerging biomonitoring data. Active, passive and surface sampling methods will be considered to identify the most relevant and cost effective method, or combination of methods for supplying data to support the interpretation of tissue residues (i.e., biomonitoring data).

2009-P-94-ISES

Incorporating an Indoor Fugacity-Based Source-to-Concentration Module into SHEDS-Multimedia

D. H. Bennett,1 V. Zartarian2; 1University of California, Davis, CA, 2National Exposure Research Laboratory, U.S. EPA, Boston, MA

The SHEDS-Multimedia model estimates human exposure to chemicals in a residential setting. To achieve this, chemical concentrations are needed as functions of time in a variety of potential contact media (e. g., textured surfaces, smooth surfaces, and air in either treated or untreated rooms). An indoor fugacity model is now used as an option for obtaining these concentrations. This paper will review the approach used to incorporate a fugacity model into the activity-based SHEDS model. Due to the low-volatility of some of the compounds of regulatory interest to the US EPA, significant research has gone into understanding the fate and transport of particulate matter in the residential environment. We will review this recent work and discuss how this research impacts the EPA approach used for indoor fate modeling.

2009-P-95-ISES

Summary Discussion, Panel Discussion and Audience Input

T. E. McKone,1 R. Maddalena,1 E. A. Cohen Hubal2; 1Lawrence Berkeley National Laboratory, Berkeley, CA, 2National Exposure Research Laboratory, U.S. EPA, Research Triangle Park, NC

Preliminary work indicates that contaminant levels in human tissues and their immediate environment depend on solution thermodynamics and on the persistence of the substance in the person and their environment. We will ask whether mass-balance models can explain current observations; assist in finding existing and “new” substances of concern; and address the lack of knowledge about the surface chemistry of human skin and hand-to-mouth behaviors as they relate to indoor pollutant uptake.

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Symposium

T-SY103: Exposures in Aircraft Cabins – ACER-RITE FAA Center of Excellence

The aircabin environment is a microenvironment with unique exposures that hundreds of thousands of air travelers and flight crew experience each day. The air within the air craft is a combination of highly recirculated air and air brought on board from high altitudes (upper troposphere to lower stratosphere) that circulates though a limited volume containing a higher density of people than just about any other microenvironment. These factors result in high levels of compounds that come from bioeffluent emissions, off-gassing furnishings, emissions from cleaning products and ozone (which is at hundreds of ppb in stratospheric air, depending upon the time of year). While the ventilation system is adjust to bring in sufficient air fresh air from the exterior of the plane, after it is conditioned to an appropriate temperature and filtered, there still will be a wider range and higher concentrations of many compounds than found in other indoor environments. In addition potential other exposures arise from: reactions of ozone with unsaturated chemical on surfaces, in the air and peoples skin or clothing; pesticides are sprayed on planes that enter some countries to stop the spread of disease associated with insects; individuals with infectious diseases travel on aircraft and can be a source of virus and bacteria to others on-board; and there is a concern that individual could release chemical or biological agents into the air on board a plane to intentionally harm others. In 2007, the US Federal Aviation Administration funded the Airliner Cabin Environment (ACER) Center of Excellence with members from seven different Universities. Several research projects conducted as part of that center are nearing completion and address issues related to exposures to chemical, biological and physical agents aboard airplanes. This symposium presents results related to exposures within commercial aircraft by ACER center members. Topics include: measurement on modeling of exposure to pesticides about aircraft, ozone and ozone by-product levels within the air cabin environment, symptom reports from passengers and crew; chemical analysis of the aircabin air; modeling of infectious agents released on-board aircraft; and measurement of circulation patterns and movement of gases and particulars within an aircraft.

2009-P-148-ISES

Pesticides Levels on Surfaces of Commercial Aircraft

B. Wei; University of Medicine & Dentistry of New Jersey, Piscataway, NJ

Disinsection, or spraying of insecticides on the surfaces of commercial aircraft has been mandated by a number of countries since the 1970s to prevent the transport of insects which can pose health threats. Disinsection, predominantly with pyrethroid insecticides, is done either as a residual treatment or by flight crew prior to descent which can result to

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potential inhalation and dermal exposure to the crew and passengers. To examine potential dermal exposure and whether there is a reservoir of pesticides within commercial aircraft we developed a wipe sampler that collects >90% of applied pesticides to hard surfaces and 60% of pesticides applied to soft surface, such as seat cushions. We determined that under laboratory settings the loading of permethrin declined exponentially from air plane seat cushions after being applied at the recommended levels 200ng/cm2, with detectable levels (~50ng/cm2) still present three months later. We have collected wipe samples from a variety of surfaces from in-use commercial aircrafts. For seventeen domestic US flights predominantly on routes that include the southeastern US only a single sample had detectable levels of either permethrin or phenothrin, from on a tray table at a loading 1.3 ng/cm2, near our detection limit. No other surfaces on that flight had measurable pesticide levels. On international routes, permethrin or phenothrin were present on 6 of 16 flights, typically on multiple surfaces when present on a flight. The loadings ranged from 1 to 52 ng/cm2 with most <5 ng/cm2 but one sample each at 18, 37 and 52 ng/cm2 suggesting that dermal and, when levels where present on tray tables, ingestion exposure is possible. Additional flights are being sampled to assess the range of pesticides within aircraft that flight to countries requiring disinsection to determine potential exposures to those flying.

2009-P-147-ISES

Computational Studies of Exposures to Pesticides in Aircraft Cabins

S. Isukapalli; EOHSI RWJMS/UMDNJ, Piscataway, NJ

Pesticide exposure in aircraft cabins is likely because of the continued use of pesticide application in domestic and international flights. Computational models can provide means for predicting exposure levels and for identifying scenarios where there could be significant pesticide exposures. The approach presented here involves the utilization of screening level and realistic simulation models of pesticide levels in aircraft cabins. Specifically, simple, one compartment models, and multi-zone models, were applied in a screening mode, and complex, computational fluid dynamics (CFD) based models were applied for detailed analyses. Scenarios simulated using CFD models include spraying towards the overhead storage bins, and upwards, with low and high air exchange rates with two different types of pesticides approved for use on flights in some countries. Specific metrics measured include surface loadings and air concentrations. These are compared with measurements conducted under the same conditions in a mockup chamber that mimics a portion of a Boeing 767 cabin. Preliminary analyses of the simulation results show that the predictions were with a factor of five of the measurements: 20 – 30 ng/cm2 for measured surface loading versus 100 – 150 ng/cm2. Similarly, preliminary analyses show that the average concentrations in the first three minutes of simulation were of the order of 1 mg/m3 in some seats. Ongoing analyses focus on interpreting these levels in the context of health risk assessments. Since the diversity of exposure conditions across different types of flights makes representative data collection very expensive, the application of detailed computational models can help in focusing data collection efforts.

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2009-P-129-ISES

Spread of Surrogate Virus and Bacteria in an Aircraft Cabin Simulation Model

H. Hirt; Kansas State University, Manhattan, KS

Modern air travel can have a considerable impact on the fast spread of infectious diseases not only by transporting infected persons quickly around the world but also for its potential to spread the infectious agent in a confined space over several hours of trans- and intercontinental flights. As the SARS epidemic and the now just emerging swine flu scare prove, old and newly emerging pathogens can quickly spread all over the world with considerable economic consequences. Case studies of pathogen spread during air travel are rare and systematic studies are hampered by the lack of adequate facilities. The Kansas State University Aircraft Cabin Environment Research Laboratory contains an eleven-row Boeing 767 mock cabin for environmental studies. We performed releases with two surrogate agents, the enveloped Escherichia coli bacteriophage PhiX174 and Lactococcus lactis. Our data indicate a clear zone of high risk around the point of release. Infectious particles and bacteria spread around the whole cabin but at numbers that suggest relative ease of containment. In the case of a one-time release, sampling 45 min after the release did detect only limited numbers of viable bacteria, indicating fast clearance by the cabin’s environmental system.

2009-P-130-ISES

Collection of Environmental Measurements and Measures of Passenger Comfort and Perception of Flight Experience on 39 Commercial Passenger Airline Flights

J. Spengler; Harvard University, Boston, MA

In-flight environmental samples were collected on 39 commercial passenger flights when the plane was above 10,000 ft. Continuous measurements (1-min ave) were made for O3, CO2, CO, ultrafine particles (UFP), PM2.5, temperature, relative humidity, pressure and sound level. Integrated samples were collected for volatile organic compounds (VOCs), carbonyls, and semi-VOCs. Passenger and crew comfort surveys were distributed during the last third of the flight. The median passenger load was 74% of total capacity. Ozone reactions creating UFP were observed on some flights which resulted in the cabin UFP counts to rise from a typical<60 particles/cm3 [p/cm3] to higher than 20,000 p/cm3 and particles being visible in the sunlight shining through cabin windows. The median values measured were: O3 (13.1 ppb), CO2 (1400 ppm), CO (0.0 ppb), UFP (42.9 p/cm3), PM2.5 (1.0 µg/m3), temperature (24.9oC), RH (11%), pressure (79.8 kPa) and sound (91.4 db). Only temperature exceeded applicable Federal and ASHRAE standards and only on one flight. Tri-o-cresylphosphate, tri-p-cresylphosphate and decanal were not detected in any of the samples collected. VOCs were measured above the detection limit in the following percentages (%) of samples: propionaldehyde (11); formaldehyde (14);

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tricresyl-m-phosphate (17); 1,3-dichloropropene (c+t) (23); 1,3-butadiene (34); nonanal (35); acetone (59); acetaldehyde (65); 2-methylhexane (69); trichloroethene (71); benzene (74); 3-methylhexane (74); 6-methyl-5-heptene-2-one (76); hexane (77); 2,3-dimethylpentane (77); methylene chloride (86); methylcyclohexane (86); methyl t-butyl ether (89); 2-methylpentane (94); 1,1,1-trichloroethane (94); chloroform (97); carbon tetrachloride (97); and o-xylene (97), with 2,2,4-trimethylpentane, toluene, tetrachlorethene, ethylbenzene, m/p-xylene, styrene, and 1,4-dichlorobenzene detected on all flights. The highest levels measured were 1,000 times less than the published occupational exposure standards.

2009-P-128-ISES

Ozone and Ozone-derived Oxidation Products on Commercial Aircraft

C. P. Weisel; EOHSI, Piscataway, NJ

Studies in a simulated aircraft cabin have indicated that ozone, at levels typically occurring during flight, reacts with surfaces to generate a series of volatile oxidation products. More than half of the identified products were carbonyls, dicarbonyls and hydroxycarbonyls derived from ozone reacting with exposed skin, hair and clothing of the occupants. This conclusion was reaffirmed in laboratory studies of skin-oil soiled clothing and hair. Major products include acetone, 6-methyl-5-hepten-2-one (6-MHO), geranyl acetone, nonanal, decanal and 4-oxopentanal (4-OPA). Several of these reached levels in the simulated cabin that raised concerns regarding their potential for contributing to mucous membrane irritation and adverse health effects (e.g., nonanal, decanal, and 4-OPA). We are presently making simultaneous measurements of ozone and ozone-derived products on actual commercial flights: ozone with a real-time dual-beam UV instrument; C6 to C10 aldehydes and 6-MHO using sorbent tubes; formaldehyde, acetaldehyde and acetone using cartridges coated with DNPH. A personal sampling pump draws air through the sorbent and DNPH cartridge, each preceded by an ozone scrubber. As of this abstract, we have sampled on 12 flights. The ozone levels have ranged from relatively low (max 1 hr ozone < 10 ppb) to moderately high (max 1 hr ozone 84 ppb). Both 6-MHO and decanal have been positively identified and appear to scale with ozone, but they have not yet been quantified. Nonanal levels in these flights have been lower than the corresponding levels of decanal. This study will be the first to report in-flight measurements of 6-MHO, nonanal and decanal; prior analyses of organics in cabin air have not been focused on such compounds. Ultimately, the collected data (concentrations of analytes in relation to measured cabin ozone levels) will significantly improve our understanding of passenger and crew exposures to ozone derived oxidation products.

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Platform

T-PL101: Exposure Determinants for Environmental Health Studies

2009-A-446-ISES

Consensus Of Environmental Exposure Measures For Genome-wide Association Studies

L. Goldman,1 D. Wagener,2 J. Haines,3 R. Kwok,2 D. Maiese,2 M. Phillips,2 E. Ramos,4 H. Junkins,4 C. Hamilton2; 1Johns Hopkins University, Baltimore, MD, 2RTI International, RTP, NC, 3Vanderbilt University, Nashville, TN, 4National Human Genome Research Institute, Bethesda, MD

Genome-wide association studies (GWAS) provide promise for the identification of genomic markers associated with different disease phenotypes, but require replication in other populations as part of their study design. This replication will allow cross-study comparisons and the pooling of results to increase statistical power for identification of genomic associations. Cross-study comparisons are also required to understand the roles of co-morbid conditions and environmental factors in the susceptibility, presentation, and progression of disease. However, the lack of comparability and consistency of the phenotypic, environmental and risk factor data frequently does not allow these comparisons or makes their interpretation difficult. To address this problem, PhenX (consensus measures for Phenotypes and eXposures) was developed to create a Toolkit of standardized disease phenotypes, risk factors, and environmental exposures that will enhance cross-study analyses of GWAS and other large-scale genomic research efforts. Twenty high-priority research domains have been selected and working groups of researchers are identifying sets of measures and standardized measurement protocols that will be recommended for future genomic studies. The PhenX Environmental Exposures Working Group consists of eight researchers from academic and government institutions whose expertise represents the breadth of environmental exposures. The selected environmental exposure domain measures presented here will assess residence, residence history, occupation, hobbies, early life exposures, environmental tobacco smoke (ETS) exposure, indoor air contaminants, specific sample collection, and time spent outdoors. These measures, identified as having high priority, will be defined and available in the PhenX Toolkit (http://www.phenxtoolkit.org) for researchers to incorporate into their own research design. This effort in the environmental exposure community to standardize phenotypic, environmental, and risk factor data will enable investigators to consistently combine and compare results.

2009-A-353-ISES

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Carex Canada National Exposure Indicators For Carcinogens In Ambient Air Phase I

E. Setton; CAREX Canada - University of Victoria Site, Victoria, BC, Canada

Objectives: Our goal is to produce estimates of the numbers of Canadians exposed, and at what levels, to a variety of carcinogens present in ambient air across Canada. Methods: In Phase I, we combined data from the National Air Pollution Surveillance network with block population estimates from Statistics Canada within a Geographic Information System (GIS) to produce indicators of ambient annual average exposure for populations living near a network monitoring station in 2006. Exposure levels were categorized using unit risk levels published by the California Office of Environmental Health Hazard Assessment (CA OEHH). Results: Indicators were produced for benzene, ethylbenzene, 1,3-butadiene, benzo[a]pyrene, lead, cadmium, nickel, dichloromethane, tetrachloroethylene, formaldehyde, and chloroform. Using a distance of 25 kilometers and the substance-specific unit risk level, we estimate that 16.6 million Canadians were exposed to benzene levels associated with an increased lifetime excess risk of cancer between 1: 100,000 and 1:50,000. Similarly, 14.3 million and 7.9 million people were exposed to 1,3-butadiene, and formaldehyde respectively within the same range of excess risk. By comparison, no populations included in the distance threshold were exposed to benzo[a]pyrene or lead at levels above the 1:1,000,000 lifetime excess risk level. Between 44 and 68 percent of Canadians did not live within the distance threshold, representing a large population with unknown exposures. Discussion: These exposure indicators provide useful information at the policy and regulatory level, particularly for identifying priority carcinogens and geographic locations for exposure reduction programs. In Phase II, now underway, we are developing high resolution spatial models in collaboration with researchers at six universities as well as Health Canada and Environment Canada. These models will integrate land use regression based local models with results from regional and national level air quality models and satellite data in support of postal code or address level exposure estimates.

2009-A-418-ISES

Developing Land Use Regression Models To Evaluate The Associations Between Particulate Matter Exposure And Recovery Of Cardiovascular Health

T. Su, C. Wu, Y. Wu, C. Chan, T. Yi, T. Cheng; National Taiwan University, Taipei, Taiwan

Numerous epidemiological studies have linked particulate matter (PM) exposure with adverse cardiovascular effects. Many of these studies used the PM measurement data collected at central monitoring stations as the exposure matrix. The objective of this study is to develop land use regression models and apply the modeling results to evaluate the PM effects on recovery of cardiovascular health in patients with heart diseases. We first

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compiled the daily PM10 and PM2.5 data collected at 17 local air monitoring stations in Taipei, Taiwan. They were used as the dependent variables in the regression models with wind speed, population density, distance to the nearest roads, rainfall, land use, and the PM measurements at the Supersite as the independent variables. We also collected 24-hr PM filter samples with Harvard Impactors at the home of a subset (n=20) of the cohort subjects. These subjects were patients with coronary heart disease and myocardial infarction. Their blood pressures (BP) and C-reactive protein (CRP) were measured twice: (1) one week after they were admitted to the hospitals, and (2) during their second visits (i.e. 3 months after they were discharged). The results show that the R2 for the PM10 and PM2.5 land use regression models are 0.82 and 0.83, respectively. Comparing the prediction values to the filter samples collected at the subjects’ home, we obtained the R2 of 0.78 and 0.87, demonstrating the validity of these models. In the health effect models with the difference between the health indices (i.e. BP or CRP) measured approximately 4 months apart as the main outcome variable (n=36), we did not observe significant effects from the PM exposures occurring during this time period (which were estimated from the land use regression models). We are currently recruiting additional subjects to increase the statistical power of our health models.

2009-A-475-ISES

The Association Between Organophosphorous Pesticide And Diakylphosphate Levels In House Dust And Urinary Diakylphosphate Metabolites In Children.

L. Quirós-Alcalá,1 K. D. Smith,2 G. Weeresekera,2 M. Odetokuns,2 D. B. Barr,2 M. Nishioka,3 B. Eskenazi,1 A. Bradman1; 1University of California, Berkeley, CA, 2Centers for Disease Control and Prevention, Atlanta, GA, 3Battelle Memorial Institute, Columbus, OH

Dialkylphosphates (DAPs), metabolites and breakdown products of many organophosphorus (OP) pesticides, are commonly used as non-specific urinary biomarkers of OP pesticide exposure in epidemiologic and exposure studies. Evidence suggests that urinary DAPs may also result from exposure to preformed DAPs in food and the environment. Under the assumption that DAPs represent exposure solely to precursor OP pesticides, these additional sources could result in overestimation of OP pesticide exposure. Previously, we established the presence of DAPs in dust. Here, we extend these analyses to determine if OP levels in dust are associated with DAPs in dust, and whether DAPs and OPs in dust are associated with urinary metabolite levels obtained from children. We collected up to two dust samples from urban and farmworker homes (n=20 homes per community). Children’s first morning void (n=79) and dust samples (n=79) were collected on the same day. Dust and urine samples were analyzed for six DAPs (diethylphosphate-DEP, diethylthiophosphate-DETP, diethyldithiophosphate-DEDTP, dimethylphosphate-DMP, dimethylthiophosphate-DMTP, and dimethyldithiophosphate-DMDTP); a subset of the dust samples (n=54) were also analyzed for 11 OP pesticides. The most frequently detected OP pesticides in dust were diazinon and chlorpyrifos with detection frequencies (DFs) of 71% and 57%,

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respectively. Both of these OPs devolve into diethyl alkylphosphates (DE). The DAPs most frequently detected in dust included DEP and DMP with DFs of 80% and 52%, respectively. Other DAPs were detected at much lower frequencies (DF<18%). Contrary to what we observed in dust, dimethyl DAPs were more frequently detected than DEs in urine. Preliminary analyses indicate that diazinon and chlorpyrifos in dust are not correlated with DE dust concentrations. Similarly, urinary DE levels were not correlated with DE, chlorpyrifos, or diazinon concentrations in dust. Our initial analysis suggests that although DAPs are present in the environment, dust concentrations are not associated with children’s DAP levels in urine.

2009-A-257-ISES

Persistent Organic Pollutants Predict Type 2 Diabetes And Related Metabolic Profiles: A Case-control Study Nested Within The Coronary Artery Risk Development In Young Adults Study

D. R. Jacobs,1 D. H. Lee,2 M. W. Steffes,1 A. Sjodin,3 R. S. Jones,3 L. L. Needham3; 1University of Minnesota, Minneapolis, MN, 2Kyungpook National University, Daegu, Republic of Korea, 3Centers for Disease Control and Prevention (CDC), Atlanta, GA

Background: Persistent Organic Pollutants (POPs) are endocrine disruptors that bioaccumulate in adipose tissue. Cross-sectional studies report POPs associations with type 2 diabetes, insulin resistance, and dyslipidemia. Methods: We conducted a prospective nested case-control study. Cases (n=90) were randomly selected from incident diabetes during follow-up from 1987-88 to 2005-06 and controls (n=90) were frequency-matched to cases on 1985-86 body mass index (BMI). POPs included 8 organochlorine pesticides (OCPs), 22 polychlorinated biphenyl congeners (PCBs), and 1 polybrominated biphenyl (PBB) measured in sera collected in 1987-88. Results: POPs showed nonlinear associations with diabetes risk. The highest risk was observed in the 2nd quartile of trans-nonachlor, oxychlordane, mirex, highly chlorinated PCBs, and PBB153, suggesting low dose effects. Since POPs concentrations reflected the exposure pattern of 1987-88, hence higher than current levels, serum POPs concentrations in the 2nd quartile were similar to high exposure levels in the current general population. We concentrated risk by summing ranks of those lipid-adjusted POPs that had individual odds ratios >=1.5 in the 2nd quartile. Given associations at low-dose, defining a reference category with very low POPs concentrations was critical for valid relative risk estimates, which we achieved by making the lowest octile of the sum of ranks the reference category. The highest risk was in the third octile, with adjusted odds ratio 6.3 (95% confidence interval 1.4-27.4); there was lower but still elevated risk in higher octiles. The low dose effects were prominent in those with BMI >=30 kg/m2. Low doses of some POPs also predicted 2005-06 BMI, blood lipids, and insulin resistance, adjusting for baseline levels. Conclusion: Various POPs may increase the risk of diabetes and related metabolic conditions in a nonlinear fashion, especially in obese persons.

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2009-A-494-ISES

Manganese Levels In House Dust In A California Agricultural Community

A. Bradman,1 D. R. Smith,2 R. Gunier,1 B. Beckerman,1 M. Jerrett,1 R. Castorina,1 M. Harnly,3 T. E. McKone,1 B. Eskenazi1; 1Center for Children's Environmental Health Research, UC Berkeley School of Public Health, Berkeley, CA, 2UC Santa Cruz, Microbiology and Environmental Toxicology, Santa Cruz, CA, 3California Department of Public Health, Richmond, CA

Mn is a naturally occurring element and essential nutrient in humans. However, at high exposure levels, Mn is a potent neurotoxicant and may affect puberty. Human exposure to Mn results from several natural and anthropogenic sources, including diet, industrial smelting, fuel additives, and pesticides. In California, approximately 1.8 million pounds of the ethylene bisdithiocarbamates (EBDCs) fungicides mancozeb and maneb are applied annually for agricultural purposes. These fungicides are ~21% Mn by weight; thus, agriculture emits approximately 378,000 pounds of Mn to the California environment each year, about 10 times more than industrial inputs. In the Salinas Valley, approximately 345,000 pounds of maneb and mancozeb are used annually, emitting ~72,000 pounds each year. We measured Mn in 75 house dust samples collected from low-income pregnant women living in the Salinas Valley. Mn was detectable in all homes with a median concentration of 173 µg/g (max=414) and a median Mn loading of 2.8 µg Mn/m2 (max=22.1). Both dust Mn concentrations and loadings were significantly higher in homes where farmworkers lived than in those without farmworkers (p<0.05). We also found a wide distribution in the ratio of Mn to aluminum, an ubiquitous component of the earth’s crust. Homes with elevated dust Mn levels showed enrichments of Mn compared to Al (i.e., an elevated Mn:Al ratio), indicative of selective anthropogenic inputs of Mn to dust. We also mapped Mn dust concentrations and used a GIS system to combined this information with local meteorological data to examine spatial trends and whether proximity to fields was related to residential Mn levels. We tended to see higher levels downwind of agricultural fields where the fungicides were applied. Overall, our results suggest that agricultural maneb and mancozeb use may increase Mn levels in residential environments and potentially expose residents, especially children who ingest more dust compared to adults.

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Interactive Poster

T-IP101: Dietary Exposure

2009-A-217-ISES

Assessing Heavy Metal Exposure From Ingestion With Multimedia Exposure Model Operating In A Geographic Information system Environment

J. Caudeville,1 G. Govaert,2 O. Blanchard,1 A. Cicolella1; 1French National Institute of Environment and Industrial Risks, Verneuil en Halatte, France, 2University of Technology of Compiègne, Compiegne, France

The last decade has witnessed an increasing interest in assessing health risks caused by exposure to the contaminants present in soils, air, food and water. In this field, Geographic Information System (GIS) may be used to produce maps of exposure and disease to reveal spatial patterns. The SIGFRIED project aims to spatialize an environmental indicator concerning human health using risk assessment methods and mapping environmental disparities. The approach is performed by a risk screening tool which employs an integrated multimedia exposure model able to manage all the steps of the analysis in a georeferenced framework operating in a GIS environment. In this study, we performed a risk assessment of metal exposure (cadmium, lead, selenium, arsenic, chromium, mercury and nickel) with a resolution of 1 km. The modeling was performed on a region of France (Nord-Pas de Calais) characterized by a heavy industrial past. The exposure pathways considered include ingestion of soil, vegetation, meat, egg, milk, fish and drinking water. Concentrations of metals on local food were calculated using a soil pollutants geodatabase and bioaccumulation food-chain models. We used water quality data and distance from river as a proxy for fish consumption exposure. Exposure scenarios were defined for different reference groups (age groups, anatomical and dietary properties, fraction of food produced locally). The results showed that the 2 to 7 age group is always the most vulnerable class of receptor. A spatial pattern analysis was performed to highlight hot-spot areas with significantly elevated risk values. In these areas, arsenic (average 43 % among metals) and vegetables (average 52 % among considered pathways) are the principal determinants of the calculated risk. In a next step, the same methodology will be used, adding inhalation pathway and organic pollutants, to map environmental inequalities in order to analyze geographic cancer disparities in France.

2009-A-373-ISES

Feasibility Of The Community Duplicate Diet Methodology - Part 1: An Overview

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L. J. Melnyk,1 M. Spruill-McCombs,2 G. Brown,2 J. Raymer,2 M. Nishioka,3 S. Buehler,3 L. Michael2; 1U.S. EPA, Cincinnati, OH, 2RTI International, Research Triangle Park, NC, 3Battelle, Columbus, OH

A dietary monitoring procedure that is population-based, termed community duplicate diet, was investigated. The purpose was to establish an alternative procedure to duplicate-diet sampling that would be more efficient for a large, defined population, e.g., in the National Children’s Study (NCS). A field study was conducted to test the feasibility of the monitoring procedure by collecting questionnaire data and food samples in a residence so as not to lose the important component of storage, preparation, and handling in a contaminated microenvironment. The participants included nine Hispanic women of child bearing age living in the Apopka, FL area. Foods highly consumed by Hispanic women were identified based on national food frequency questionnaires and prioritized by permethrin residue concentrations as measured for the Pesticide Data Program. Participants filled out questionnaires to determine if highly consumed foods were commonly eaten by them and to assess the collection protocol of the food samples. The food samples were composited based on likelihood of permethrin contamination to avoid multiple nondetectible levels and analyzed for a range of pesticides and phthalates. The estimated permethrin exceeded the measured concentrations; however, measureable levels of permethrins were found in the 90% of the samples. Analytical results and questionnaire responses indicated that the community duplicate diet method is feasible for a defined population. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy

2009-A-428-ISES

Feasibility Of The Community Duplicate Diet Methodology, Part 2 Statistical Simulations To Inform Sample Compositing And Study Design

L. C. Michael; RTI International, Research Triangle Park, NC

In large studies involving many participants, traditional duplicate diet collections and analyses for the estimation of dietary exposures may be more burdensome and/or costly than available resources could support; community-based approaches might provide comparable information. Using data from nine Hispanic women residing in Apopka, FL, simulation experiments were conducted to determine an appropriate scheme for compositing 67 individual food samples into 20 composited samples when permethrin was the target analyte. Consumption behaviors were derived from NHANES, and distributions of pyrethroid residues were compiled from Pesticide Data Program and Total Diet Study databases. These data, along with observed participant diaries, were used to create sample composites in a manner to maximize the likelihood of measuring permethrin residues in each composite. Using actual residues measured in the composite samples, generalized linear models were employed to estimate the pesticide concentration in each of five food groups.

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A second simulation study was conducted to illustrate the utility of published pesticide measurements and dietary behaviors in formulating a sample design for a larger, hypothetical study. Number of visits, potential stratification variables and intra-person correlation of pesticide residue were examined to improve the quality of estimates of community- level intake for each pesticide. Intra-participant correlation values were then used to demonstrate the effect on study cost of drawing a sample from a similar population. Based on the simulated results, an increase in the number of collection events beyond two was found to provide only minimal additional information. Inclusion of demographic covariates to improve the predictive ability of the modeled permethrin intake showed that only country of origin had an impact. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy

2009-A-434-ISES

Feasibility Of The Community Duplicate Diet Methodology- Part 3: Measurement Of Pesticides In Community Duplicate Diet Food Samples

M. G. Nishioka,1 S. Buehler,1 M. McCauley,1 K. Andrews,1 L. Melnyk,2 L. Michael3; 1Battelle Memorial Institute, Columbus, OH, 2US EPA, Cincinnati, OH, 3RTI International, Research Triangle Park, NC

Low level detection of pesticides in food samples remains a challenge because of the complexity of the food matrix, and the highly variable nature of the samples. Extraction and cleanup methods must be used to target removal of fats, carbohydrates, sugars, and proteins so as to ensure low level (<1 ppb) detection. Our recently developed method was applied to the analysis of 67 individual duplicate meal samples, and 20 composite samples of these individual meals. These food samples were collected to assess a community duplicate diet methodology. Pesticides included diverse pyrethroids, plus organophospahtes such as chlorpyrifos, chlorpyrifos methyl, diazinon, and phosmet. Pesticide spike recoveries at 5X the method detection limit (spike level of 0.5 ng/g; n=5) averaged 60% for diazinon, 87% for chlorpyrifos, 101% and 105% for cis- and trans-permethrin, 92% for bifenthrin and 122% for esfenvalerate. Detection frequency and ranges included: diazinon (4%; 0.05-0.2 ng/g); chlorpyrifos (57%; 0.06-1.84 ng/g); permethrins (48%; 0.1-34 ng/g); esfenvalerate (19%; 0.25-19 ng/g), and bifenthrin (55%; 0.07-135 ng/g). The significant finding is the high detection frequency and high levels of the pyrethroid bifenthrin in these samples. Bifenthrin is not metabolized to any of the commonly measured urine pyrethroid metabolites (3PBA, CA, DCCA, DBCA) and, thus, urinary screening for exposure assessment may be missing an important contributor to current pesticide exposure. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy

2009-A-340-ISES

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Estimating Concentrations Of Chlorpyrifos In Blood From Dietary Exposures Using Linked Exposure And PBPK Models

P. Price,1 P. Hinderliter,2 T. Poet,2 K. Schnelle3; 1The Dow Chemical Company, Midland, MI, 2Pacific Northwest National Laboratory, Richland, WA, 3Dow AgroSciences, LLD, Indianapolis, IN

As with most crop protection chemicals, the use of chlorpyrifos on several important crops can result in trace dietary exposure to the general population. The oral doses from these low-level exposures are characterized based on surveys of dietary residues and use of dietary exposure models. This paper presents the preliminary results of an assessment of the impact of these exposures on blood levels and cholinesterase levels in adults (age 30) and children (age 3). The assessment uses a combination of physiologically-based, pharmacokinetic and pharmacodynamic (PBPK/PD) models with models of both variation in human physiology, and longitudinal models of dietary exposures. These linked models allow the inclusion of objective data on variation in diet, physiology, and metabolism, and produce direct estimates of internal concentrations and effects. Publicly available dietary residue data (USDA PDP, FDA, and EPA RED) and publicly available dietary software models (CARES and LifeLine) are used to estimate longitudinal exposures (five consecutive daily doses) for 1,000 adults and 1,000 children for the years 2002-7. PBPK/PD, physiology, and dietary exposure models are linked using the “person-oriented approach” developed for the USEPA. Interindividual variation in physiology is simulated using the approach used in P3M. The combined model directly predicts the interindividual variation in exposure, intestinal and hepatic bioactivation and detoxification, and circulating blood levels. Interindividual variation in kinetics and level of activity were investigated but found to have minimal impact on the variation in blood levels. Our initial assessment suggests that 90% of the blood levels of chlorpyrifos taken at random times during the day will range from 0.1 to 2 ng/l for adults and 0.5 to 6 ng/l in children. Models of the impact of these levels on cholinesterases inhibition indicated no change in blood or brain cholinesterase.

2009-A-480-ISES

The Food Commodity Intake Database Updated With Foods From What We Eat In America

D. E. Hrdy; United States Environmental Protection Agency, Washington, DC

The U.S. EPA's Office of Pesticide Programs (OPP) in its conduct of dietary risk assessment for pesticides is most interested in consumption of food commodities in the form of ingredients such as water, wheat, paprika, onions, soy oil, lamb, tomato juice, etc. rather than foods "as eaten" (e.g., lamb goulash). While the USDA's Continuing Survey of Food Intake by Individuals (CSFII) provides extensive, statistically-representative information on food consumption for approximately 22,000 surveyed individuals, information on food commodity consumption with foods expressed in terms of

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ingredients is not present. As a result, the Food Commodity Intake Database (FCID) was developed as a cooperative effort by USDA and the Office of Pesticide Programs for use by EPA and other organizations when conducting exposure assessments for food ingredients. FCID was developed using reported intake data from CSFII 1994-96/1998 which was translated to a food commodity basis: more specifically, the FCID database uses recipe files to break down all foods into their agricultural commodity equivalents. Of course, all the demographic, geographic, socio-economic, racial/ethnic and other information reported for that respondent in CSFII would also be available in FCID. FCID would also contain additional information with respect to the cooked status and food form of the ingredients which is not reported in CSFII. In total, commodity intakes in FCID are expressed as grams consumed per kilogram of body weight per day for over 500 commodities derived from more than 6,000 different foods and beverages reported in the CSFII. EPA’s OPP is currently updating this database to include the more recent NHANES (National Health and Nutrition Examination Survey) consumption data as determined by the USDA's "What We Eat in America" program. This updated database is expected to cover food commodity consumption through 2006.

2009-A-447-ISES

U.S. Food and Drug Administration (FDA)’s Updated Estimates of Dietary Exposure To Perchlorate

C. W. Murray, S. K. Egan, P. M. Bolger; Center for Food Safety and Applied Nutrition, US Food and Drug Administration, College Park, MD

Perchlorate is used as an oxidizing agent (e.g., rocket propellant), occurs naturally in some fertilizers and may be generated under certain climatic conditions. It has been detected in surface and groundwater and in food. Perchlorate at high doses (e.g., pharmacological) can interfere with iodide uptake into the thyroid gland, disrupting its function. Over the last several years the FDA has been conducting surveys of perchlorate in foods in order to assess dietary exposure. These surveys include sampling of both targeted foods suspected to contain perchlorate and a wider range of foods from the FDA’s annual market basket survey, the Total Diet Study (TDS). The purpose of these efforts is two-fold. First, to obtain an overall picture of the presence of perchlorate in the diet and to derive estimates of overall dietary exposure. Second, to determine the range of levels in specific foods that contain the highest levels of perchlorate and to assess their contribution to overall dietary exposure. Since perchlorate demonstrates significant water solubility, foods that contain a significant portion of water (e.g. lettuce) are believed to have the highest levels of perchlorate and have been the focus of the targeted sampling effort. Since the TDS includes foods that represent the ;main components of the average American diet, results from that study supplement data from the targeted sampling This assessment updates and expands previous FDA monitoring activities of perchlorate and the estimation of dietary intake of perchlorate. This updated analysis makes use of the most recent consumption data from National Health and Nutrition Examination Survey (NHANES). Finally, this analysis provides estimates of mean and upper-percentile

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exposure for foods with the highest levels of perchlorate, as well as perchlorate exposure from a wide range of foods for specific age-sex groups in the U.S. population.

2009-A-500-ISES

Comparison Of Measured And Modeled Methods Of Assessing Dietary Arsenic

M. O'Rourke, M. Kurzius-Spencer, J. Roberge, P. Hsu, R. Harris, J. Burgess; The University of Arizona, Tucson, AZ

Diet is a source of arsenic exposure in populations with low levels of arsenic in drinking water. Using archived questionnaire and laboratory data from the Arizona Border Survey (ABS), our goal is to model the contribution of dietary arsenic intake in solid foods to arsenic exposure as measured by urinary arsenic. Assessing available data on arsenic concentrations in specific food items is a critical first step. In this analysis, we compare: 1) total dietary arsenic derived from ICP/MS analysis of duplicate diet samples, 2) mean total dietary arsenic concentrations from food items thought to comprise 90% of dietary arsenic intake (Schoof et al., 1999) modeled using food diaries and quantities measured in the ABS duplicate diet samples, and 3) mean total arsenic concentrations derived by modeling the ABS data and US FDA Total Diet Study (TDS) Market Baskets 1991-2005 (USFDA, 2007). The sum of measured total dietary arsenic from solid foods ranged from 6-720 ng/g based on laboratory analysis, 40.3-48902 ng/g based on Schoof’s values, and 0-10208 ng/g based on TDS values. All distributions were highly skewed to the right. The median total arsenic calculated using Schoof’s values was two orders of magnitude greater than the laboratory measured total arsenic values (18.0 vs. 1853.3 ng/g). Using the TDS dietary arsenic database, ~half the population consumed undetectable amounts of total arsenic. There was no correlation (n=52, Spearman r= 0.159, p=0.259) between laboratory measures and modeled values calculated using Schoof’s data or for modeled TDS data. However, the TDS calculated values and the Schoof calculated values were correlated (n=53, Spearman r=0.432, p=0.001). Possible explanations include regional differences in source of foods and differences in sensitivity of the analytical methods, but additional modeling in this and other study populations is needed.

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Wednesday, November 04, 2009

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Symposium

W-SY101: Residential Exposures to Endocrine Disrupting Compounds from Consumer Products and Building Materials: Recent Findings and Future Directions

There is tremendous interest in the potential health effects of endocrine disrupting compounds (EDCs) from consumer products and building materials, however research is hampered by our inability to characterize exposure to these complex mixtures. In fact we know so little about key sources of exposure to these compounds that it is difficult to make evidence-based recommendations about ways to reduce exposure. While indoor exposures have decreased over the years for some chemicals (e.g. VOCs, formaldehyde), indoor exposures to many EDCs have increased due to their growing presence in consumer products and building materials. More indoor sources coupled with a trend of decreasing residential air exchange leads to increased exposures to EDCs and potentially adverse health effects. Many common indoor contaminants have been identified as EDCs, including certain alkyphenols, parabens, pesticides, phthalates, polybrominated diphenyl ethers (PBDEs), organochlorines, glycol ethers and others. Since many EDCs act through common biological mechanisms, research on mixtures in residential environments will inform epidemiological study design and cumulative risk assessment. This symposium will showcase current research focused on understanding exposure to EDCs from consumer products and building materials. Presentations will cover the following topics: indoor-outdoor air concentration relationships for a broad suite of EDCs; multiple pathway exposure assessment for phthalates; cumulative exposure assessment for PBDEs and PCBs - two distinct families of thyrotoxic compounds; exposure to glycol ethers - an emerging class of EDCs; and translation of exposure science into policy and action to reduce exposures. Each presenter will include 1-2 slides describing new technologies or approaches they believe will advance this area of research, and the set of presentations will be followed by a discussion to highlight key directions for future research in this field - for example technologies for integrated functionally-relevant measurements of chemical mixtures, and evaluation of indoor air quality in green buildings. The symposium will be moderated by Ruthann Rudel, director of research at the Silent Spring Institute. Ms. Rudel has directed several exposure studies of endocrine disrupting compounds in residential environments, publishing results of a household exposure study that identified over 30 EDCs for the first time in residential air and dust. After her brief introduction there will be five presentations followed by 30 minutes for discussion.

2009-P-158-ISES

Endocrine Disrupting Compounds in Paired Residential Indoor and Outdoor Air Samples from Two Northern California Communities: Comparisons and Relationships

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R. E. Dodson, J. G. Brody, R. A. Rudel; Silent Spring Institute, Newton, MA

A suite of 106 endocrine disrupting compounds (EDCs) were measured in paired residential indoor and outdoor air samples from 50 homes in California: 40 homes in the urban area of Richmond and 10 homes in the more rural town of Bolinas. Compounds of interest include phthalates, alkylphenols, flame retardants, polyaromatic hydrocarbons (PAHs), pesticides, and phenols. Many of these compounds were measured for the first time in outdoor air. Overall, we detected 66 target analytes in indoor and 42 in outdoor air. Wilcoxon rank sum test was used to compare concentrations. Levels of 12 chemicals were significantly higher in Richmond than Bolinas outdoor air, including 9 PAHs, 2 phthalates, and o-phenyl phenol. Diethyl phthalate (DEP) had higher concentrations in Bolinas outdoor air compared to Richmond. Levels of 5 chemicals were significantly higher in Richmond than Bolinas indoor air, including DEP and PAHs. Indoor air concentrations were generally higher than outdoors across all chemical classes, indicating primarily indoor or mixed indoor and outdoor sources. Twenty-one chemicals were significantly higher indoors, and none were significantly higher outdoors. Indoor-outdoor differences were also used to evaluate the relative importance of indoor versus outdoor sources of EDCs. Overall, the differences were mostly positive across all chemical groups, with many significantly positive differences and no significantly negative differences. Indoor and outdoor concentrations of PAHs are most correlated, indicating that indoor concentrations are due to a mix of indoor and outdoor sources. Most other compounds (e.g. phthalates) do not show correlation between indoor and outdoor levels, suggesting indoor concentrations are primarily due to indoor sources. Residents are exposed to a mix of EDCs, resulting primarily from indoor sources. Identifying co-occurring chemicals can provide insight into common exposure mixtures and key sources of exposure.

2009-P-198-ISES

Environmental Levels for Organic Compounds in the Indoor Environment

D. H. Bennett,1 R. Moran,1 N. S. Tulve,2 M. G. Nishioka,3 M. S. Clifton,2 W. S. Weathers,2 I. Hertz-Picciotto1; 1University of California, Davis, CA, 2U.S. EPA, Research Triangle Park, NC, 3Battelle, Columbus, OH

The SUPERB Study (Study of Use of Products and Exposure-Related Behaviors) is an evaluation of alternative platforms for collecting longitudinal data related to non-occupational environmental exposures for a random sample of households with a child between the ages of 18 months and 8 years and households with an older adult. We are currently conducting a sub-study that includes environmental and biological sampling. Eighty-two families and 33 households with older adults have been enrolled to date. Environmental samples collected from each home include two types of dust samples (vacuum bag and HVS3), passive indoor air samples (polyurethane foam), and surface wipe samples (floors and windows). A home walkthrough questionnaire collected information on potential sources of PBDEs, specifically furniture and electronics. We

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will present results on PBDEs, pesticides, and bisphenol-A in the environmental samples collected in a subset of the homes. In addition, we will present results from a pilot study that included 12 mother-child pairs and their potential exposures to a suite of phthalates through inhalation and ingestion (duplicate diet and dust).

2009-P-160-ISES

Cumulative Exposures to Thyroid Hormone Disrupting Compounds (PCBs and PBDEs) in Residential House Dust

A. R. Zota,1 G. Adamkiewicz,2 J. D. Spengler,2 R. Morello-Frosch,3 J. G. Brody,1 R. A. Rudel1; 1Silent Spring Institute, Newton, MA, 2Department of Environmental Health, Harvard School of Public Health, Boston, MA, 3Department of Environmental Science, Policy and Management & School of Public Health, University of California, Berkeley, Berkeley, CA

Polybrominated diphenyl ethers (PBDEs) and polychlorinated biphenyls (PCBs) are structurally similar, persistent pollutants that disrupt thyroid hormones. Penta-BDE mixtures have been used to reduce flammability of furniture foam manufactured from the 1970s to 2004 with highest use in California due to flammability standard TB117. PCBs were used in the 1950s-1970s, primarily in industrial and electrical equipment, with some use in residential building materials. Thus, household PCB and PBDE levels are not expected to be correlated. Both chemicals have been measured in residential dust, but, few studies have considered cumulative exposures. PBDE (-47, -99, -100) and PCB (-52, -104, -153) congeners were measured in the house dust of 270 homes at five study sites: Bolinas and Richmond, CA; Cape Cod and Roxbury, MA; and Gadsden County, FL, using similar sampling methods. For sites with detection frequencies above 30%, Kendall’s tau rank correlations were used to assess correlations between PBDEs and PCBs. For each site, dust concentrations of each chemical class were ranked in quartiles and a chi square test was performed to test the independence of high PBDE and PCB homes. PBDEs were detected more frequently and at higher concentrations than PCBs at all sites. ∑PBDE concentrations, highest in CA, ranked in the following order (95th percentile, µg/g): Richmond (120), Bolinas (72.5), Roxbury (17.6), Cape Cod (9.0), and Gadsden (6.5). ∑PCBs concentrations, highest in MA, ranked in a different order (95th percentile, µg/g): Cape Cod (4.0), Roxbury (2.7), Richmond (0.87), Gadsden (0.18), and Bolinas (0.12). PBDE and PCB concentrations were not correlated (τ = -0.06 to -0.02), and high PBDE homes were independent of high PCB homes. Health studies that use PBDE or PCB dust concentrations as exposure measures would reduce exposure misclassification by evaluating both chemical classes simultaneously since they are structurally similar and exposures are uncorrelated.

2009-P-197-ISES

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Home Exposure to Endocrine Disrupting Chemicals and the Asthma Risks in Toddlers

H. Choi,1 S. Janson,2 S. Moniruzzaman,2 M. Larsson,2 C. Boman,2 E. Nånberg,2 M. Hasselgren,3 F. Lundin,3 L. von Kobyletzki,2 B. Jönsson,4 C. Bornehag2; 1Harvard School of Public Health, Boston, MA, 2Karlstad University, Karlstad, Sweden, 3County Council of Värmalnd, Karlstad, Sweden, 4Lund University, Karlstad, Sweden

Objectives: Current understanding on health effects of endocrine disrupting chemicals during the early-life through multiple routes is limited. Here, we summarize the lessons from multi-phase cross-sectional study of 10,851 pre-school age children in Värmland, Sweden. In addition, we describe our on-going data collection scheme of a new prospective birth cohort study on 1900 mother-newborn pairs. Methods: In the cross-sectional study, dust and air samples were collected in the children’s bedroom. Building inspectors also examined moisture problem and indoor air quality. The air samples were analyzed for volatile organic compounds. The dust samples were analyzed for 2-ethylhexyl phthalate (DEHP) and butyl benzyl phthalates (BBzP). In the present birth cohort study, blood and urine samples are being collected from the pregnant women at 10th week of gestation. Samples of cord blood and urine are repeatedly collected during first three years. Concurrently, questionnaires on life-styles and indoor sources of exposure are collected. In addition, routine health status data are collected from the well-baby clinic. Results: Based on repeated questionnaire administration, wheezing during early life was associated with subsequent asthma diagnosis. Soft polyvinyl chloride (PVC) flooring material significantly increased the likelihood of the asthma. PVC flooring was a potent source of both DEHP and BBzP in the settled dust. Furthermore, DEHP concentration significantly increased the asthma in a dose-respondent manner. Glycol ether concentration in the indoor air independently elevated the likelihood of multiple allergic symptoms, rhinitis, and eczema, respectively. Conclusion: Several phthalate compounds and glycol ethers significantly increased the risks of asthma and allergy symptoms. Our present exposure assessment aims to further clarify the relative importance of the respective routes, and human uptake of selected chemicals during putative critical window.

2009-P-440-ISES

Science in Action: Consumer and Policy Initiatives to Prevent Exposures

K. Schuler; Institute for Agriculture and Trade Policy, Healthy Legacy Coalition, Minneapolis, MN

This presentation will describe Healthy Legacy, a campaign for “safe products, made safely,” as a model for informing and protecting consumers from exposures to endocrine disrupting chemicals in everyday consumer products, as well as activating citizens to support protective policies. Groups like Healthy Legacy use scientific research to educate consumers on safer products to prevent personal exposures and to help move markets

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toward safer chemicals. We also use peer-reviewed science to support policies that protect public health. In addition to hard science, we use “body burden” and product testing projects as important tools to highlight common chemical exposures. Minnesota is one of many states which has proposed and/or passed policies to phase out endocrine disrupting chemicals of concern, including: phthalates, bisphenol A and brominated flame retardants. In addition several states have proposed or passed larger framework bills to address all problem chemicals in children’s products. These approaches employ a new paradigm for regulating chemicals of concern, one based on the inherently hazardous properties of the chemical, versus the current approach, “risk assessment” for which exposure must be quantified. An important component of this approach is “alternatives assessment” and phasing out chemicals of concern if safer alternatives are available.

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Platform

W-PL101: Global Exposure Management

2009-A-292-ISES

European Health Risks Of Indoor Air Exposures

M. J. Jantunen,1 E. Oliveira Fernandes,2 P. Carrer,3 O. Seppänen,4 S. Kephalopoulos5; 1National Institute for Health and Welfare, Kuopio, Finland, 2University of Porto, Porto, Portugal, 3University of Milan, Milan, Italy, 4REHVA, Brussels, Belgium, 5EC Joint Research Centre, Ispra, Italy

EnVIE quantified the causes of the indoor air health risks in Europe, related these risks to specific contaminants and sources of the contaminants, and assessed public health potentials of alternative indoor air policies. Passive smoking was acknowledged as the best known and most important indoor air pollutant, but due the rapidly advancing policies excluded from the analyses. A short list, based on expert panel judgement, of the most significant indoor air quality (IAQ) related health outcomes was created, representing the bulk of the European burden of disease (BoD) attributable to IAQ. For each health outcome the total national BoD in disability adjusted life years (DALY) was first obtained for each country from WHO and national statistics, and the fractions attributable to IAQ were estimated from the exposure and dose/response data to estimate the respective indoor air BoD (IABoD). The final list consists of cardiovascular diseases (670 kDALY/year), asthma (660), sensory irritation (incl. SBS, 520), lung cancer (130), carbon monoxide poisoning (100), COPD (60), and respiratory infections (50), in this order. The estimated total EU-27 wide IABoD, was 2.2 million DALY/year. The most significant causal pollutants for the IABoD were combustion products (950), bioaerosols (690), VOCs (320), CO (100), pathogens (100) and radon (80). The contributing sources of IABoD were outdoor air (1100), dampness and mould (360), heating and combustion (290), furnishings, interior materials and electric appliances (130), building site (80), household chemicals (70), ventilation and air conditioning systems (50) and building materials (30). Highest public health benefits were estimated on one hand for general policies on building codes, management, documentation and maintenance, and on the other for ventilation and air cleaning in polluted urban environments. Acknowledgement: EnVIE project funding by EC, 6th Framework Programme, Priority 8.1, Policy oriented research (SSP), 2004.

2009-A-509-ISES

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Multi-continental Long Range Transport Of POPs. Air Advection Versus Food Trade

S. Shaked,1 D. Friot,2 S. Humbert,3 O. Jolliet1; 1University of Michigan, Ann Arbor, MI, 2Paris-Tech Ecole des Mines, Sophia Antipolis, France, 3Ecointesys-Life Cycle System, Lausanne, Switzerland

Globalization and the resulting increase in food imports and exports could also represent an important factor in transporting persistent and bioaccumulating organic pollutants (POPs) to other countries and continent. Dioxin founds in exported chicken from Asia constitutes a good example So far none of the model has been able to account for the exchange of pollutants in food exports. We therefore aim to develop a spatial multi-continental multi-media model that a) estimate multi-continental population intake of organic substances throughout the globe, accounting for advection across continents b) evaluate the importance of pollutant transferred through food export impacted by the pollution. The first module is a new global multimedia model called IMPACTWorld dividing the world into 17 continental zones and 9 ocean zones. The second component is an environmentally extended economic Input-Output module based on the GTAP v.6 database. It describes the production, consumption and trade of goods between 19 regions and 24 sectors for the year 2001. The intake fraction (iF) - the fraction of the emission that is taken in by the population - is highest when emitted in regions with high food production. For dioxins (2,3,7,8 TCDD), it varies between 3,000 ppm and 35,000 ppm depending on the region of emission. Intercontinental transport through atmospheric advection represents between 9% and 95% of the iF with a median of 33%. This was assuming that the food produced in the region was consumed in the same region. The intercontinental trade of food, represents an additional 9% to 74% intercontinental transport, increasing the overall transported fraction between region to between 18% and 99% of the iF. Therefore Import - exports of POPs in food do matter and are as important as long range environmental transport and should deserve much more attention in future research on long range transport.

2009-A-312-ISES

Environmental And Sustainability Factors And Research Needs Associated With Next-generation Biofuels

P. R. D. Williams,1 D. Inman,2 A. Aden,2 G. A. Heath2; 1E Risk Sciences, LLP, Boulder, CO, 2National Renewable Energy Laboratory, Golden, CO

Modern liquid biofuels are promoted in the United States (U.S.) as a means of achieving national energy independence and security and reducing greenhouse gas (GHG) emissions. In this presentation, we summarize what is known or anticipated about environmental and sustainability factors associated with next-generation biofuels relative to the primary conventional biofuels in the U.S. during feedstock production and conversion processes. Factors considered include GHG emissions, air pollutant

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emissions, soil health and quality, water use and water quality, wastewater and solid waste streams, and biodiversity and land-use changes. Next-generation feedstocks are categorized as follows: (1) the cellulosic components of municipal solid waste (e.g., tree trimmings, yard waste, paper products), (2) forest residues and thinnings (e.g., logging residues from commercial forests), (3) annual crop residues (e.g., corn stover), (4) dedicated herbaceous perennial energy crops (e.g., switchgrass, Miscanthus, native prairie grasses), (5) short-rotation woody crops (e.g., hybrid poplar, willow shrubs, eucalyptus), and (6) microalgae. The two next-generation conversion technologies considered in this assessment are ethanol produced via a biochemical (enzymatic or acid hydrolysis) process and ethanol produced via a thermochemical (gasification) process. Our assessment includes both a qualitative high-level review of the current literature as well as quantitative modeled estimates of environmental emissions, waste streams, and water consumption. We describe the uncertainty in current estimates of environmental and sustainability factors, and discuss key data gaps and research needs.

2009-A-380-ISES

Exposure Assessment For Cumulative Health Impacts Of Gasoline And Alternative Transportation Fuels

A. Lobscheid,1 J. Apte,2 B. Strogen,2 A. Barrett,2 A. Horvath,2 T. E. McKone1; 1Lawrence Berkeley National Laboratory, Berkeley, CA, 2University of California, Berkeley, Berkeley, CA

The Federal Energy Independence Security Act of 2007 will increase the share of low-carbon biofuels to at least 36 billion gallons by 2022, or approximately 20% of the total on-road motor vehicle fuel used in the US. Before biofuels are widely deployed, it is important to characterize their human health benefits and impacts relative to gasoline. To address this, we use a life-cycle-impact-assessment (LCIA) framework for VOC and PM2.5 emissions from various fuel life-cycle stages, including fuel production/refining, transport, storage and fuel use (combustion). We present characterization factors (CFs) to track VOC and PM2.5 chemical releases, exposures, and health impacts at various fuel life-stages. In our LCIA framework, CFs combine an environmental fate-factor and an exposure factor to obtain a human intake fraction (iF). The iF is the ratio of chemical emissions-to-human-intake use to characterize cumulative inhalation and ingestion exposures at regional (urban and rural) and county scale. Systems models provide iF values by tracking the exchange of chemicals among environmental compartments. Sensitivity analysis reveals that important information gaps include: 1) emission factors for production and use of emerging biofuels and 2) biofuels environmental data including the partitioning, reaction and multimedia transport properties of a chemical in the environment. We use classification and regression tree analysis to determine how to best assess the properties of gasoline mixtures and remove some of these data gaps. For gasoline VOC emissions, the majority of health damage arises from fugitive emissions from service stations and local fuel distribution by truck. For gasoline, however, the largest disease burden arises from particulate matter emissions during combustion. Our

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preliminary estimates indicate that a 10% reduction of the life-cycle emissions from gasoline (mainly combustion emissions) could avoid up to 20,000 disability adjusted life years (DALYs). But there is significant spatial heterogeneity in the distribution of this benefit.

2009-A-265-ISES

Exposure-based Prioritization Among Air Pollution Control Strategies In Yangtze River Delta, China

Y. Zhou,1 J. S. Fu,2 J. I. Levy3; 1Emory University, Rollins School of Public Health, Atlanta, GA, 2University of Tennessee, Knoxville, TN, 3Harvard University, School of Public Health, Boston, MA

The Yangtze River Delta (YRD) is the fastest growing economic development region in China and one of the most densely populated regions in the world. Although there has been a dramatic increase in energy consumption and atmospheric emissions in YRD, existing studies have not provided adequate information to determine how different sectors influence population exposures and the corresponding health risks in this area. We apply the state-of-the-science Community Multiscale Air Quality Model (CMAQ) and an INTEX-B based emission inventory in YRD we developed for year 2006. Pollutant concentration for fine particulate matter (PM2.5), sulfur dioxide, nitrogen oxides (NOx), and ozone are calculated using a three-way nested model with 27 km, 9 km and 3 km grid resolutions respectively. The base case CMAQ simulation is validated using monitoring data from Shanghai. Additional scenarios that represent perturbations to baseline cases are simulated, in order to model the marginal contribution to the baseline concentration from different sectors in YRD. In designing these scenarios, we focus initially on NOx emission control, which increased the fastest from 2001 to 2006 among different pollutants under study. Among the six different sectors in the emission inventory, we focus on large point sources, industrial sources and mobile sources, since they account for over 90% of NOx emissions in China. The health benefits from NOx control are related to the health effects of PM2.5 (i.e., secondary nitrate) and ozone. Our findings indicate that among the different sectors, there is a significant variation in terms of benefits per ton of NOx control. The greatest benefits of realistic NOx control strategies are from sectors with both higher population exposure per unit emissions as well as significant co-benefits. These findings provide the basis for prioritizing NOx control strategies in YRD and provide a template for comparable analyses elsewhere.

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Symposium

W-SY102: Use of Molecular Tools for Source Identification and Risk Assessment in Water Contaminated by Feces

Purpose: A 90 minute symposium describing the use of molecular methods for assessing the risks due to exposures to contaminated drinking or recreational waters and for tracking fecal contamination back to its environmental sources. Abstract: Exposures to water contaminated by fecal material can potentially lead to adverse health effects, particularly if the exposures are to untreated groundwater or recreational water. Methods used for routine bacteriological monitoring of water for evidence of fecal contamination are adequate for identifying recent fecal contamination but do not reveal the sources of that contamination. Recently a number of methods that utilize principles of molecular biology have been developed to distinguish whether fecal contamination detected in water is from high risk human sources or lower risk animal sources. Some of these bacterial identification methods are highly discriminatory and can distinguish the species of origin making them not only useful for risk assessment but also useful for identifying the exact source of the contamination. Once the sources are known, it is then possible to reduce or eliminate the contamination at the source and prevent future exposures. This session will describe the evaluation of PCR-based methods for bacterial host-specific markers for characteristics such as specificity, sensitivity and abundance in feces of target versus non-target animals and the use of these methods to identify the sources of fecal contamination in a system of small streams in a Southwestern Ohio watershed and at a beach in Southern California. The final presentation of this session will describe a novel PCR approach that targets mitochondrial DNA from animal cells that are sloughed off during defecation rather than bacterial DNA. This method can detect in a single assay human, bovine, ovine, porcine and chicken mitochondrial DNA in water and has been used to characterize contamination in river samples and wastewater samples.

2009-P-223-ISES

Single Laboratory Evaluation of Host-Specific PCR Assays for the Detection and Quantification of Human and Bovine Fecal Pollution

O. C. Shanks; U.S. EPA, Cincinnati, OH

Identification of microbiological hazards in waters used for recreational activities or as drinking water supplies is becoming more important as the demand for these resources increase. We describe the evaluation of 24 PCR and quantitative real-time PCR (qPCR) assays reported to identify either bovine or human sources of fecal pollution. Each assay was tested against a reference collection of 444 individual fecal samples from more than 30 different animal sources and 56 sewage samples collected from different geographic

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locations. Fecal and sewage reference collections were used to determine specificity, sensitivity, prevalence for all PCR assays. For qPCR assays, calibration curve performance parameters including amplification efficiency, linearity, range of quantification, and precision were determined. In addition, the abundance of each qPCR genetic marker was estimated in both target and non-target animal sources and compared to quantities of Bacteroidales determined by real-time 16S rRNA qPCR. Some genetic markers of bovine fecal pollution were widely distributed in cattle ranging from 38.5-93.2% and assays yielded specificity levels from 48.9% to 100%. All genetic markers of human fecal pollution were broadly distributed among sewage samples (96.8-100%) and specificity of these assays ranged from 0% to 96%. The relative abundance of bovine-associated genetic markers suggests that changes in animal management practices can have a dramatic impact on the concentration of DNA targets resulting in poor assay performance. In contrast, human-associated genetic markers exhibited low variance estimates for mean log10 DNA target copy number (0.09 to 0.30) among sewage samples. In summary, experiments indicate large discrepancies in assay performance and genetic marker host distribution suggesting that some assays are more suitable for microbial source tracking applications than others.

2009-P-224-ISES

Combining Watershed Variables with PCR-based Methods for Better Characterization and Management of Fecal Pollution in Small Streams

L. A. Peed,1 C. Nietch,1 C. A. Kelty,1 K. White,1 J. Blannon,1 M. Meckes,1 T. Mooney,2 M. Sivaganesan,1 R. A. Haugland,1 O. C. Shanks1; 1U.S. EPA, Cincinnati, OH, 2University of Cincinnati, Cincinnati, OH

Ability to distinguish between human and animal fecal pollution is important for risk assessment and watershed management, particularly in bodies of water used as sources of drinking water or for recreation. PCR-based methods were used to determine the source of fecal pollution and to characterize the relationship between fecal pollution, land use, surface water nutrients, precipitation, and other in-stream indicators of water quality. Stream water samples (n = 193) were collected monthly over a two year period from ten channels draining subwatersheds with different land use intensities. The sampling effort was part of a multidisciplinary program designed to characterize and manage water quality in the 320,000 acre East Fork Watershed of Southwestern Ohio. PCR-based methods included 14 PCR and quantitative real-time PCR (qPCR) assays that detect enterococci, E. coli, Bacteroidales as well as human- and bovine-associated genetic markers. Human-specific qPCR assays tested positive for 20-45% of subwatershed samples and >94% of samples were positive with general fecal indicator assays suggesting routine occurrence of fecal pollution in all streams. An analysis of variance indicated that when there was > 0.25 inches of rainfall within 24 hours (wet season) prior to sampling there was a significant increase in genetic marker concentrations for all qPCR assays (p < 0.05). Simple linear regression analysis indicated a significant effect (p < 0.05) between all human-associated genetic marker concentrations and septic tank

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density for wet season samples suggesting that failing septic systems are a major source of pollution after rain events. Our data analyses demonstrate that combining PCR-based measurements of fecal contamination with land use trends and water quality variables can provide a more complete understanding of microbial pollution, leading to more focused watershed management efforts.

2009-P-225-ISES

Application of Molecular Source Tracking Methods within Epidemiological Studies of Water Contact Illness at Marine Beaches in Southern California

J. F. Griffith; Southern California Coastal Waters Research Program, Costa Mesa, CA

We describe the simultaneous application of a wide variety of molecular source tracking methods to water samples collected during epidemiological studies of water contact illness at southern California beaches. A broad suite of new measurement methods and indicators based on molecular measurement technology have been developed to assess beach water quality, but they have generally been subjected to limited testing outside of the laboratory in which they were developed. Here we evaluated bacterial and viral analytes using ambient marine water samples. Each method was evaluated with respect to its correlative relationship to Enterococcus measured by EPA Method 1600, to other source-specific indicator methods, and to the same method performed by a different researcher. Levels of enterococci were generally a poor predictor of concentrations of sources-specific markers and relationships between source-specific methods were similarly weak. Levels and types of markers detected varied between and within study sites. Among human viruses, polyoma virus was detected most often. Other human viruses were detected in only a small number of samples. We also found that investigator-specific variations of methods targeting the same organism often produced different results. The between beach variability in levels of source specific markers seen in this study suggest that certain markers may be more appropriate for use at specific beaches than others and that it may be necessary to employ pilot studies using a suite of different source methods and markers to determine which are most appropriate for a particular locale.

2009-P-226-ISES

Mitochondrial DNA as a Tracer for Fecal Contamination Source Tracking

P. Payment, R. Villemur; INRS Institut Armand-Frappier, Laval, QC, Canada

Mitochondrial (mt) DNA has the potential to be used as an animal-specific genetic marker for source-tracking of fecal contamination in surface waters and groundwaters. We have developed of a method to detect in a single assay human, bovine, ovine, porcine and chicken mitochondrial (mt) DNA in water. Consensus nucleic sequences were found

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between human, bovine, porcine, ovine and chicken mtDNA to design three sets of polymerase chain reaction (PCR) universal primers. Upon PCR with a digoxigenin labeled nucleotide and the universal primers, species determination is carried out by dot-blotting membranes containing specific oligonucleotides for these five animals. The method was tested with river and wastewater samples, and the results were compared with those obtained by multiple nested PCR with specific primers for these five species. The dot-blot assays were as specific and sensitive as the nested-PCR approach. The proposed method has the advantage that it requires the use of only one PCR assay per sample and very little amounts of DNA. This method shows the way for the development of DNA arrays for source tracking of various animal species in water. This method should help evaluate risks associated with various animal fecal sources that carry pathogens that can be of concern for specific population given their host specificity.

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Platform

W-PL102: Engineered Nanomaterials

2009-A-471-ISES

Identification Of Population Groups Exposed To Engineered Nanomaterials

D. L. MacIntosh, J. G. Allen, J. H. Stewart; EH&E, Needham, MA

Engineered nanomaterial (EN) is a rapidly growing class of materials in commerce that is important to environmental health. While useful performance attributes of EN particles, wires, and films have been identified, their potential for dispersal in the environment, persistence, uptake into organisms, and influence on health is not well understood. Identification of population groups with non-occupational and non-medical exposure to EN is an essential component of characterizing the safety of these materials for the general public. To address this need, a review of the state of knowledge on population groups potentially exposed to EN in non-occupational and non-medical settings was conducted. The results were used to inform a gap analysis for information and tools relevant to improved exposure assessments for EN. Information currently available indicates that ingestion of nanomaterials in food and inhalation of nanoparticles from consumer goods, such as personal care and cleaning products, have the greatest potential for peak internal human exposure in the general population at present. Similar to other engineered materials in commerce, if EN are persistent in the environment then dispersion of EN from waste streams and earlier stages of the life cycle may be a source of low level, multi-route exposure for the general population in the future. Current information also indicates that nanoparticles engineered in the range of 10 to 80 nm are present in exposure media as clusters that are several hundred nanometers in size. The implications of this knowledge are considered with respect to the utility of current methods of population-scale exposure assessment for evaluation of potential exposure to EN. The gap analysis focuses on treatment of nanoscale materials in transport and fate models such as AERMOD and CMAQ, exposure simulation tools such as SHEDS, and population-based monitoring programs such as the NAMs/SLAMs network and the Total Diet Study.

2009-A-463-ISES

Comparing Exposure Groups By Different Exposure Metrics Using Statistical Parameters: Contrast And Precision

J. Park, G. Ramachandran, P. C. Raynor, L. E. Eberly; University of Minnesota, Minneapolis, MN

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Recently, the appropriateness of using the “mass concentration” metric for ultrafine particles has been questioned and surface area or number concentration metrics have been proposed as alternatives. In order to find appropriate exposure metrics for classifying exposure categories in workplaces generating nanoparticles, exposure concentrations were measured in high and low exposure groups in a restaurant, an aluminum die-casting factory, and a diesel engine lab using surface area, number, and mass concentration metrics. Predetermined exposure classifications were compared using statistical parameters and concentrations ratios which were calculated from the different exposure concentrations. In the restaurant, surface area and fine particle number concentrations showed significant differences between the high and low exposure groups and they had higher contrast (the ratio of group variance to the sum of the between-group and within-group variances) than mass concentrations. Mass concentrations did not show significant differences. In the die cast facility, concentrations of all metrics were significantly greater in the high group than in the low group. Surface area and fine particle number concentrations showed larger concentration ratios between the high and low groups and higher contrast than mass concentrations. In the instance that showed a small difference between high and low exposure groups like the diesel engine lab, none of metrics were found to be significantly different. Fine particle number and surface area concentration were more related to incidental nanoparticle generation sources than were mass concentrations and better reflect nanoparticles’ size characteristics. Instead of mass concentration, the use of fine particle number and surface area concentration is recommended to classify exposure groups. That exposure categories depended on the exposure metric chosen has significant implications for epidemiological studies.

2009-A-241-ISES

Simulating The Stability Of Colloidal Amorphous Iron Oxide In Natural Waters

N. T. Loux; U.S. Environmental Protection Agency, Athens, GA

Anecdotal evidence suggests that there are more than 800 commercial products containing manufactured nanomaterials in commercial production and that this number is expected to increase in an exponential fashion. Unfortunately, existing standardized test guidelines designed to assess the environmental mobility of commercial products are not likely to be directly applicable to insoluble nanomaterial suspensions in natural waters. This work describes findings from an ongoing effort designed to assess the utility of the historical Derjaguin-Landau-Verwey-Overbeek (DLVO) theory of colloidal particle stability when used in conjunction with legacy Diffuse Layer (DLM) and Triple Layer (TLM) electrostatic surface complexation models. Due to the availability of data, colloidal amorphous iron oxide was selected as a test substrate and the likelihood of its forming stable suspensions over a pH range of 4 to 10 was assessed in simulated 0.7 M seawater, 0.1 M diluted seawater, world average river water, continental U.S. average groundwater and 50th percentile midwestern U.S. rainwater. Findings from the work included: 1) legacy surface complexation models are likely to overestimate the diffuse layer potential (and stability) of smaller, nanosized colloidal particles, 2) both DLM and

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TLM models predict unstable iron oxide suspensions in the 0.7 and 0.1 M seawater systems and both models predict stability in most of the rainwater simulations, 3) the DLM diffuse layer potential estimates generally exceeded the TLM values and there was not agreement concerning stability assessments in the simulated river and groundwaters, 4) the major ions present in natural waters are likely to have a profound impact on system-dependent diffuse layer potentials and 5) findings from both models were at least qualitatively in agreement with observations reported in the literature. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

2009-A-236-ISES

Ultrafine Particles Produced By Power Tools

M. Green, L. Wallace, A. Persily; NIST, Reston, VA

Electric motors have the potential to release ultrafine copper particles due to spark discharge between the graphite brushes and copper wiring. Copper is a transition metal suspected of causing health effects. Many homes have appliances with electric motors, such as vacuum cleaners and power tools. We investigated ultrafine particles in the 2-64 nm range produced by typical power tools such as drills, saws, and sanders. Particles were measured using a Scanning Mobility Particle Sizer (SMPS, Model 3081, TSI, Inc. Shoreview, MN). The SMPS employs a nano-Differential Mobility Analyzer (nano-DMA), able to size particles as small as 2 nm. The particles were counted by a water-based Condensation Particle Counter (CPC) (Model 3786, TSI, Inc. Shoreview MN). Two scenarios were tested for each source to estimate the exposure of (a) the user of the tool and (b) another person in the same house but a separate room. In the first scenario, the tool was run for a short time (4 minutes) in a bedroom with the door closed and the central fan off. In the second scenario, the tool was run in the kitchen with the central fan on and the particles were measured in the bedroom with the door open. The number concentrations for the user ranged from none for a pump, compressor, and hedge clippers to more than 100,000 particles per cm3 for two power saws and a belt sander. Exposures for the non-user were normally less than 15,000 cm-3 for all tools except for one power saw, which produced concentrations near 70,000 cm-3. Particle modes during the peak concentrations were about 6-10 nm. These measurements show that power tools can produce substantial concentrations of ultrafine particles from 2-20 nm.

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Platform

W-PL201: Biological Exposures

2009-A-568-ISES

Standardization Of Allergen Sampling In Indoor Environments: Performances Of Three Commonly Used Samplers

J. Adgate,1 S. Cho,2 S. Banerjee,1 G. Ramachandran,1 M. Wang,1 J. Wang1; 1University of Minnesota School of Public Health, Minneapolis, MN, 2NIOSH, Morgantown, WV

Allergens and other pollutants in house dust are collected using a variety of dust samplers. This study quantified sampler performance under controlled environmental conditions to compare the differences between three commonly used samplers and develop methods to standardize allergen sampling. House dust with known particle size characteristics (212-90, 90-45, and <45 microns) and allergen concentrations was embedded in new carpet squares using ASTM method F608-97 under controlled environmental conditions (%RH of 20, 50 or 80%). Dust mass and allergen recovery for total dust mites (Der p1 and Der f1), cat (Fel d1) and cockroach allergens (Bla g1) were assessed for three samplers (the Eureka Mighty Mite [EMM] with Dustream collector, the HVS3, or the American Industrial Hygiene Association [AIHA] method). Allergen concentrations were quantified by a commercial laboratory using ELISAs, and dust mass results corrected for carpet fiber shedding. Samplers were compared by exploring mass collection efficiency (CE= Fiber Corrected Dust Mass/ Applied Dust Mass), concentration ratio (CR =Allergen concentration in sample/Allergen concentration in test dust) and allergen collection efficiency (ACE =CE*CR). Test dust allergen concentrations varied by particle size fraction, especially for cockroach allergen, indicating varying laboratory performance. The EMM and HVS3 had CEs of 41 to 63% across the two smaller particle size fractions, with the AIHA collecting little dust in the large size fraction, and about half the typical mass of dust of the other samplers for the medium and small size fractions. The AIHA and HVS3, however, were more likely to collect samples that were more representative and had less variable CRs compared to the EMM method, suggesting that the higher CE of the EMM may be counter productive. Implications of these findings for standardized sampling of house dust allergens are discussed in the context of health-based standards.

2009-A-443-ISES

Determination Of Indoor Airborne Endotoxin Levels In Homes Of Paris Area

C. Dassonville,1 C. Demattei,2 B. Vacquier,1 V. Bex-Capelle,3 N. Seta,1 I. Momas1; 1Universite Paris Descartes, Paris, France, 2Departement de l'information medicale, CHU

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de Nimes, Nimes, France, 3Laboratoire d'Hygiene de la Ville de Paris, Mairie de Paris, Paris, France

Background. Studies dealing with the health impact of endotoxin exposure in infancy usually sample house dust but rarely house air. Objective. The aim of this study was firstly to assess airborne endotoxin levels in dwellings of newborn babies living in Paris and secondly to identify the predictors for these levels in relation to housing factors and living conditions. Methods. Air samples were collected twice a year on a glass fibre filter in polystyrene filter holders, using a device at a flow rate of 3.5 L/min for 24 hours placed in the main room of the home. Endotoxin levels were measured using a chromogenic kinetic Limulus Amoebocyte Lysate test and expressed as Endotoxin Unit (EU). Housing factors and living conditions were provided by a questionnaire administered by an interviewer. Results. The study included 162 dwellings of newborn babies in Paris. Geometric means (standard deviation) of airborne endotoxin levels at two different visits were respectively 0.509 (4.289) EU/m3 and 0.557 (3.029) EU/m3, and did not differ significantly (p=0.62), although not being correlated. The GEE multivariate model explained 15.8 % of the variability of airborne endotoxin levels. Airborne endotoxin levels significantly increased: in cold season (p=0.024), with the presence of visible cockroaches in the previous twelve months at home (p<10-4); with the number of inhabitants per square meter (p=0.012), with the high frequency of cleaning with the floor cloths (p=0.0014) and with the low frequency of vacuuming (p=0.0045). A rubbish chute in the flats decreased airborne endotoxin concentrations (p=0.003). Conclusion. This study provides for the first time airborne endotoxin levels in Paris dwellings issued from repeated measurements. These low levels were in line with values previously found in urban settings and showed large within-home variability over time.

2009-A-268-ISES

Modeling Daily Pollen Exposures In The Eastern United States

C. DellaValle,1 M. Bell,1 E. Triche2; 1Yale University, New Haven, CT, 2Brown University, Providence, RI

Estimating pollen exposure is challenging due to low spatial coverage for publically available monitoring networks and potential spatial heterogeneity of pollen levels. Establishing new monitors is costly and labor intensive. The development of statistical models could offer a reliable and cost-effective alternative to improve pollen exposure estimation. In this study statistical models were developed to estimate daily pollen exposures. Daily pollen counts were obtained from the National Allergy Bureau for 10 eastern U.S. cities for 2003-2007. Land-cover characteristics were obtained from the U.S. Geological Survey Land-Cover Institute. Weather data (temperature, dew point, precipitation, wind speed) were obtained from the National Climactic Data Center. Daily counts (total and by pollen type) were estimated using linear mixed model regression, generalized estimating equation (GEE), polynomial splines, and kriging. Variables included daily and seasonal

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weather characteristics, land cover and day of season. Temperature had a positive association with daily pollen counts whereas precipitation had a negative association, consistent across all model results. Day of season was significantly associated with all pollen measures. Accuracy was assessed by determining the frequency of correct model-predicted pollen counts within categories of absent and percentiles (50th, 75th, 90th). Linear mixed models and GEE represented daily variations better than spline or kriging models. Overall both mixed and GEE models predicted daily counts with 52% accuracy. Mixed models predicted absent to 50th percentile values better than other models, with 84% accuracy. GEE models predicted counts >90th percentile with the highest accuracy (78%). Results are comparable to correlations between counts at nearby monitoring stations within 50 miles. This work provides methodologies to estimate pollen counts for places and time periods without monitoring data. The best model varied by the level of pollen counts. Better ability to estimate pollen exposure can contribute to improved management and treatment of allergy symptoms.

2009-A-437-ISES

Impact Of Ultra Violet Light Equipped Vacuum Cleaner Use On Surface-bound Culturable Microorganisms On Carpets

E. A. Lutz, S. Sharma, B. Casto, G. Needham, T. J. Buckley; The Ohio State University, Columbus, OH

Carpets are both sinks and sources for exposure to chemicals, allergens, and microbes and consequently influence health, including; asthma, allergies, and infectious diseases. Asthmatics, children, and persons who are immune-compromised are at particular risk. To address this risk, a residential vacuum cleaner with UVC was commercially developed. However, its effectiveness in reducing microbial load in carpet remains to be demonstrated in practice. Accordingly, the purpose of the current study was to evaluate the effectiveness of a UVC-equipped vacuum in reducing the surface-bound microbial load in carpets. We sought to isolate the influence of the UVC from the vacuum and the beater-bar. This was accomplished by sampling the surface of 9 ft2 carpet sections for microbes before and after treatment. Sampling was conducted using contact plates (Sabouraud’s dextrose agar) that were incubated for 24-hours before the total number of colony forming units (CFU) was counted. Three different indoor carpets types representing real-world settings (residential and institutional) were tested; medium-Berber, loose-Berber, and commercial tight-loop. Two-minute treatment periods were conducted for: 1-UVC light only (UV), 2-beater-bar with vacuum (BB-V), and 3-combined UVC and BB-V (COMB) treatment groups. Forty pre- and 40 post-treatment samples were collected in each treatment group. The treatment effect was evaluated by considering the decrease in CFU from pre- to post-treatment using ANOVA. The treatments yielded an average 3-fold decrease for UV (p <0.05), a 4-fold decrease for BB-V (p<0.05), and an 8-fold decrease for COMB (p<0.05) in carpet surface microbial load. Accordingly, the UVC and BB-V are comparable and additively account for the

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combined effect. Therefore, we conclude that a UVC equipped vacuum approximately doubles the vacuums effectiveness in reducing surface-bound microbial load, thereby holding promise as a means for decreasing indoor infectious disease risk.

2009-A-454-ISES

Exposure Assessment Of Airborne Ammonia And Bos d 2 (Cow Allergen) In Settled Dust Samples Collected From Homes In An Agricultural Region With Industrial Dairy Operations

D. L. Williams, A. S. Geyh, M. C. McCormack, S. McKenzie, P. N. Breysse; Johns Hopkins School of Public Health, Baltimore, MD

Community exposures to contaminants from industrial food animal production facilities (IFAP) are poorly characterized and understood. Proximal communities may be subject to elevated short-term and long-term exposures to particulate matter (PM), gases, and biological agents from these operations. Two objectives of a current study in the Yakima Valley WA, where 79 industrial scale dairies are in operation, are to investigate concentrations of indoor and outdoor ammonia and settled dust contaminants from homes in close proximity to IFAP, < 3 miles (proximal n=24), to homes > 3 miles distant (distal n=16) from IFAP. Homes (n=40) without livestock were recruited into this study. Indoor and outdoor ammonia samples were collected for 5 days using Ogawa passive badges and standardized collection methods. Analysis of ammonium was conducted using IC. Indoor and outdoor settled dust samples were collected by vacuum using standardized home collection methods. Analysis of settled dust was conducted by ELISA for Bos d 2 (a cow allergen). Indoor and outdoor ammonia concentrations in proximal homes were 2.5 and 5 times higher than distal homes, p = 0.003 and p > 0.001 respectively. Bos d 2 was found in the indoor dust samples of 75% of sampled homes. Indoor and outdoor concentrations of Bos d 2 in proximal homes were 2.6 and 4.1 times higher than distal home environments, p = 0.03 and p = 0.002 respectively. Ammonia concentrations in proximal homes are similar to previously studied areas with intensive swine operations. In addition, detection of Bos d 2 allergen inside homes in this agricultural region documents a direct pathway for IFAP-specific contaminants to infiltrate homes proximal to these facilities. Further research is necessary to determine the impact of IFAP contaminants on the health of communities living in close proximity to these facilities.

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Symposium

W-SY201: Integrative Exposure Biology and Computational Toxicology for Risk Assessment - Session A

Understanding the relationships between environmental exposures and health outcomes requires integration of a wide range of factors—extrinsic (e.g. environmental), intrinsic (e.g. genotypic), and mechanistic (e.g. toxicolgic)—to assess risk. Application of modern methods in molecular biology and advanced computational tools provide the potential to understand complex exposure-outcome systems. A new generation of scientific tools, including transcriptomics and high throughput assays, is emerging that can rapidly measure signals from cells, tissues, and organisms following exposure to chemicals. Combined with development of widely accessible databases and advances in computational technologies for efficient analysis of multidimensional data, these tools are facilitating a “paradigm shift” in characterization of human-environment interaction for risk assessment. A reverse-engineering or systems-biology approach for holistic study of environmental disease considers coupled networks that span multiple scales of biological organization. Mechanistic understanding is derived by characterization of these networks and impacts of perturbations due to behavioral and environmental influences. This symposium will present recent advances in integrative exposure biology and computational toxicology for risk assessment. Specifically, it will bring together presentations from a team of computational scientists, with diverse backgrounds in biological, chemical and environmental informatics. Presentations will address multiple elements of the toxicant source-to-outcome sequence including: application of informatics tools for toxicant characterization; integration with individual and population exposure modeling tools; and enhancement of current quantitative risk assessment. The proposed presentations highlight progress towards mechanism-based environmental health risk assessments in a person-oriented framework that accounts for simultaneous exposures to contaminants from multiple media, routes and pathways. Application of such a multidisciplinary environmental systems approach to evaluate exposure and hazard is expected to facilitate development of more accurate, and eventually even “personalized,” risk assessments.

2009-P-192-ISES

ExpoCast: Exposure Science for Prioritization and Toxicity Testing

E. Cohen Hubal; US EPA, National Center for Computational Toxicology, RTP, NC

The US EPA is completing the Phase I pilot for a chemical prioritization research program, called ToxCastTM. Here EPA is developing methods for using computational chemistry, high-throughput screening, and toxicogenomic technologies to predict

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potential toxicity and prioritize limited testing resources. There is a clear need for a parallel and collaborative effort across the exposure and risk assessment community to provide the exposure science required for interpretation of high-throughput in vitro toxicity data. A coherent research program is required to advance exposure characterization to translate advances and findings in computational toxicology for enhanced risk assessment, informed decision making and improved public health. US EPA is initiating the ExpoCast program to ensure that the required exposure science and computational tools are ready to address global needs for rapid characterization of exposure potential arising from the manufacture and use of tens of thousands of chemicals and to meet challenges posed by new toxicity testing approaches. ExpoCast will provide an overarching framework for science required to characterize biologically-relevant exposure in support of the Agency computational toxicology program. The overall goal of this program is to develop novel approaches and tools for evaluating and classifying chemicals, based on potential for biologically-relevant human exposure, to inform prioritization and toxicity testing. Broadly and long-term, the ExpoCast program will foster novel exposure science research to (1) inform chemical prioritization, (2) understand implications of system response to chemical perturbations at the individual and population levels, (3) link information on potential toxicity of environmental contaminants to real-world health outcomes. This presentation will introduce EPA’s ExpoCast program. This work has been reviewed and approved by the US EPA for publication but does not necessarily reflect Agency policies.

2009-P-577-ISES

Linking Exposure Dynamics with Health Effects through Biological Modeling: Case Study with TCE Exposure and Oxidative Stress

C. J. Brinkerhoff, P. G. Georgopoulos; Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, NJ

Trichloroethylene (TCE) is a commonly encountered multimedia contaminant due to its widespread use as a degreaser and general-purpose solvent. It is a known carcinogen in rodents and suspected carcinogen in humans. One of the hypothesized mechanisms of TCE toxicity is through oxidative stress, which is a well-known mechanism of cellular injury leading to carcinogenesis. Mechanistic understanding and predictive modeling of this pathway in combination with population exposure is expected to significantly improve our understanding of risks from TCE exposures. A new combined physiologically based pharmacokinetic (PBPK) and biologically based dose response (BBDR) model is developed based on invitro data from hepatocytes. This model describes mechanistically the toxicokinetics and oxidative stresses due to the metabolites of TCE, such as trichloroacetic acid (TCA) and dichloroacetic acid (DCA), since many of the toxic effects of TCE are thought to be due to TCE metabolites. The mathematical formulation of the BBDR improves upon existing TCE models for oxidative stress

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generation by considering direct exposures to the metabolites. Model parameters were estimated systematically using in vitro measurements in mouse hepatocytes following exposures to TCE and TCA. The model can thus estimate relative contributions of each chemical to the total oxidative stress caused by a dose of TCE in humans. This model resulted in successful predictions of oxidative stress over time periods ranging from hours to weeks; such consistent predictions across large time scales were not possible with existing models. Additionally, the linked model is applied for studying the distribution of TCE exposures and oxidative stress production in a population. Support for this work has been provided by USEPA GAD R 832721-010 and NIEHS P30ES005022. This work has not been reviewed by and does not represent the opinions of the funding agencies.

2009-P-570-ISES

Pathway Modeling of Microarray Data of the Rat Testes after in utero DBP Exposure

M. A. Ovacik,1 M. G. Ierapetritou,1 P. Georgopoulos,2 W. Welsh,2 S. Euling,3 B. Sen,4 K. Gaido,5 I. P. Androulakis1; 1Rutgers University, Piscataway, NJ, 2UMDNJ, Piscataway, NJ, 3U.S. EPA/ORD/NCEA, Washington, DC, 4NIEHS, U.S. EPA, Research Triangle Park, NC, 5The Hamner Institute, Research Triangle Park, NC

In utero dibutyl phthalate (DBP) exposure in rats results in developmental toxicity of many male reproductive organs. Previous analyses of the microarray data focused on pathways of interest to pursue an understanding of modes of action (MOA) associated with male reproductive development. For example, analysis of microarray and toxicology data led to the identification of a decrease in testosterone levels in the testis as one MOA affecting testicular development in the rat. It is of interest to know whether there are additional pathways and thus, MOAs that may be affected after in utero DBP exposure. Typically, pathway analysis of microarray data is performed in a two step process: identification of statistically significant differentially expressed genes followed by pathway mapping. The approach pursued in this study, pathway activity level (PAL), focuses on all genes that are known to be members of metabolic and signaling pathways as defined by KEGG. The motivation behind developing PAL is that modest but consistent changes in the expression of a group of related genes could be missed if relatively few of the individual genes appear significant. PAL utilizes singular value decomposition (SVD) of the expression data of the genes constituting a given pathway. The activity level of a pathway is therefore the aggregated change of gene expressions in the given pathway. Here, we explore an extension of the pathway activity methodology and use it to model temporal transcriptional profiling data after DBP in utero exposure. Additionally, we developed a cross-species pathway comparison analysis method. This method evaluates various pathway similarity metrics based on enzyme presence, enzyme sequence, and gene promoter sequence similarity information. The relations between different animal models and human are discussed for some of the pathways affected after in utero DBP exposure.

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Support for this work has been provided by USEPA GAD R 832721-010. This work has not been reviewed by and does not represent the views of the USEPA or its contractors.

2009-P-571-ISES

Multiscale Mechanistic Models in Exposure Assessment: Case Studies with Virtual Organs

S. Isukapalli; Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, NJ

Development of formulations representing “virtual” (or “in silico”) tissues and organs at various levels of detail enhances the mechanistic understanding of health risks associated with environmental factors. Particular attention in ongoing efforts is given to models of the skin and the liver. The skin is the largest organ of the human body in terms of surface area and directly interfaces with the environment, often being the “first line of defense” of the organism to xenobiotics. The liver is often the site of chemical modulation/metabolism in the body. Mechanistic modeling of these organs can provide critical insight into the underlying toxicokinetic and toxicogenomic processes governing dose-response. Depending on the type exposure scenario, the level of detail in modeling an organs varies substantially, thus necessitating a library of “virtual organ” modules for mechanistic modeling of dose-response in different types of exposure scenarios. Therefore, various mathematical formulations of these organs are developed as components of a library of virtual organs. These modules include simple compartmental models, distribution-based models, cell-level models, and agent-based models, and are geared towards integration into modular whole-organism simulation systems for toxicokinetics and toxicodynamics. The virtual library offers a platform for combining in silico biology methods with available in vitro and in vivo data. This virtual library will eventually allow characterization of toxicokinetic and toxicodynamic variability within a population of concern. Case studies are presented that study exposures to dioxin compounds and volatile organic chemicals, with a focus on identifying the appropriate level of detail required for different exposure scenarios. Support for this work has been provided by USEPA GAD R 832721-010 and NIEHS P30ES005022. This work has not been reviewed by and does not represent the opinions of the funding agencies.

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Platform

W-PL202: Microbial Occurrence in the Environment

2009-P-219-ISES

Exposure to Pathogenic Viruses in Coastal Systems in the Great Lakes

J. B. Rose; Michigan State University, Lansing, MI

Waterborne diseases are influenced by sewage inputs to drinking and recreational waters. For molecular tools to advance decision-science for public health protection, sample concentration, hazard characterization, quantification, and/or viabililty will need to be addressed for waterborne pathogens in environmental waters. Human viruses are pathogens responsible for many disease idiopathies ranging from mild gastroenteritis to more severe neurological symptoms. Their presence at high numbers in human excreta has been well documented and their high potency and resistance to wastewater treatment makes them of great concern relative to many bacterial pathogens. The Great Lakes are a unique coastal environment, used not only as a source of fresh water for municipal, agricultural and industrial use, but they support a significant commercial and sport fishing industry. Every year millions of people visit the 500 plus recreational beaches in the Great Lakes. Pollution, beach closures and recreational disease are all of notable occurrence in the Great Lakes and the data to date suggests that viral pollution in these waters is part of the problem. Current detection methods are limited in their ability to detect and evaluate multiple virus types from single samples. PCR-integrated cell culture, qPCR, and viral microarrays to screen municipal wastewaters and beaches for the presence of enteric human viruses have been used to address public health risks. Adenoviruses were commonly observed, but RNA viruses were more frequently detected in sewage compared to DNA viruses when analyzed by microarrays. Some seasonality among certain viral groups was observed; other viral groups were shown to be ubiquitously present in sewage. The occurrence on beaches was related predominantly to wind.

2009-P-220-ISES

Surveillance Systems for Waterborne Cryptosporidium: Past, Present, and Future

E. N. Villegas; US Environmental Protection Agency, Cincinnati, OH

Cryptosporidium oocysts continue to contaminate drinking water supplies worldwide. To reduce human health risks posed by this contaminant, more specific detection and typing approaches are being developed to better understand occurrences and impact of Cryptosporidium oocysts in drinking water systems. These new methods can also provide

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additional information that will be useful for future source water management strategies and human exposure assessments related to waterborne disease outbreaks of cryptosporidiosis. Current research activities focused on developing new and more rapid molecular-based approaches that can detect and determine the infectious potential of Cryptosporidium oocysts will be described. Advantages, limitations, and their potential application(s) as alternative Cryptosporidium oocyst surveillance systems will be discussed.

2009-P-221-ISES

Exposure to Enteric Viruses from Small Community Groundwater Systems

M. A. Borchardt; Marshfield Clinic Research Foundation, Marshfield, WI

Although human enteric viruses have frequently been found in groundwaters that are vulnerable to contamination from human sources, it is often assumed that the confined sand and alluvial aquifers common in the upper Midwest are not vulnerable. To examine the vulnerability of these aquifers, 14 community systems serving untreated groundwater to populations of 1,219 to 8,320 were monitored for viruses using conventional and molecular methods. Viruses were detected in samples from wells and tap water in all 14 communities. Community incidence rates of acute gastrointestinal illness (AGI) were estimated from health diaries completed weekly by households within each study community (n = 673 households, 1786 people). AGI incidence was related to tap water virus concentrations using Poisson regression with random effects. The arithmetic mean and maximum concentration of total viruses in the communities’ tap water was positively associated with AGI (P-values = 0.012 and 0.006, respectively). Virus exposure resulting in significantly elevated AGI risk occurs whenever the mean concentration of enteric viruses is greater than two genomic copies per liter. Similar significant associations were observed between G1 norovirus and AGI. Enterovirus levels were weakly related to adult AGI and no relationship was found between AGI and adenoviruses. Research is ongoing in these communities to determine the proportion of AGI attributable to drinking water exposures.

2009-P-222-ISES

Detection and Characterization of Mycobacterium avium Complex Organisms in Drinking Water

S. Pfaller; US Environmental Protection Agency, Cincinnati, OH

The Mycobacterium avium Complex (MAC) includes the species M. avium (MA), M. intracellulare (MI), and others. MAC are listed on the U. S. Environmental Protection Agency's Contaminant Candidate List 2 (CCL2) due to their association with human disease and occurrence in public drinking water systems. Current methods for detecting

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MAC organisms in drinking water are culture-based. However evidence suggests that culture-based methods have severe limitations including long incubation periods, loss of target due to overgrowth of background organisms, up to 70% loss of target due to harsh decontamination techniques, and inability to recover MAC in a viable-but-non-culturable state. Because of these drawbacks and the need for more accurate and comprehensive occurrence data, we have developed real-time QPCR assays for detection and quantification of MA, MI, and MA subsp. paratuberculosis (MAP) in drinking water. Real-time QPCR assays can be used in combination with culture-based methods in order to confirm viability of MAC in samples, as well as provide isolates for further characterization. We are currently evaluating these methods for use on actual drinking water samples in order to generate a more complete understanding of MAC occurrence in drinking water.

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Platform

W-PL203: Relating Indoor-Outdoor Air

2009-A-482-ISES

Time Series Study Of Fine Particulate Matter Source Apportionment For Use In Health Assessment In Seven California Counties From 2001-2005

Z. Chowdhury,1 R. Anousheh,1 R. Broadwin,2 B. Malig,2 B. Ostro2; 1San Diego State University, San Diego, CA, 2California Office of Environmental Health Hazard Assessment, Oakland, CA

A time-series study of receptor oriented PM2.5 source apportionment was conducted in seven of the largest California counties (Fresno, Kern, Los Angeles, Riverside, Sacramento, San Diego, and Santa Clara) from 2001 to 2005. The daily chemically speciated ambient dataset for all seven counties was obtained from the California PM2.5 Speciation Network and was analyzed spatially and temporally to display trends in the ambient dataset. The source apportionment of fine particulate matter work was completed by day (N = 4,376) and by seasons (N = 189) as well as annually (N = 48) using the Chemical Mass Balance Modeling (CMB8.2) approach with ambient data and source profiles containing trace elements, ionic species, organic carbon, and elemental carbon. A total of eight major sources were identified and quantified for each of the counties: mobile, biomass, fuel oil, natural gas, oil dust, brake dust, sea salt, and secondary particulate matter. The largest component of the fine particle mass for all counties was secondary in nature consisting mostly of secondary nitrates (30-60%) and sulfates (~11%). On the other hand, depending on the county, the sources of the primary particulate matter were mostly vehicle emissions (10-25%), biomass burning (10-30%) and re-suspended soil dust (10-30%). Spatial trends were observed for some of these sources with higher vehicle emissions in Los Angeles and Riverside counties and higher biomass and re-suspended soil dust in Kern and Fresno counties. The seasonality of these sources across California will be presented. The results from this time-series source apportionment study will be subsequently used in a follow-up paper to examine association of PM2.5 with daily mortally and morbidity using hospital admissions data during this same period.

2009-A-486-ISES

Indoor And Outdoor Carbon Concentration Of Fine Particulate Matter In A Mega City: Mumbai, India

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A. E. Joseph,1 S. Unnikrishnan,1 R. Kumar,2 Z. Chowdhury3; 1National Institute of Industrial Engineering, Mumbai, India, 2National Environmental Engineering Research Institute, Mumbai, India, 3San Diego State University, San Diego, CA

The present study monitored indoor and outdoor fine particles (PM2.5) in four sites categorized as control (C), kerb (K), residential (R) and industrial (I) within Mumbai city, India during summer, post-monsoon and winter seasons for seven consecutive days during year 2007-2008. The average outdoor PM2.5 mass concentrations at C, K, R and I site were 77.6±18.19, 96.3±35.47, 88.9±39.12, 96.8±24.53 µg/m3 and indoors was 93.7±4.99, 99.1± 47.4, 69.8±27.02, 76.6±28.05 µg/m3 respectively. The Indoor/Outdoor (I/O) ratio for PM2.5 was 1.24±0.23, 1.01±0.12, 0.8±0.07 and 0.78±0.18 at the respective sites. Elemental Carbon (EC) and Organic Carbon (OC) values in fine aerosol have been estimated for indoor and outdoor air using thermal optical reflectance method. The average annual OC contributions at C, K, R and I sites outdoors were 25.15%, 33.07%, 36.86%, 30.04% respectively and indoors were 32.45%, 28.55%, 35.12%, 25.19% respectively. On the other hand, for the same sites outdoor EC contributions were 6.66%, 11.11%, 8.73%, 7.86% and indoor were 9.99%, 13.23%, 9.46% and 4.72% respectively. The I/O ratio for OC was 1.66±0.6, 0.96±0.2, 0.79±015, 0.78±0.41 whereas for EC was 1.73±0.66, 1.21±0.29, 0.73±0.39, 0.48±0.24 respectively. Pearson correlation coefficients were estimated to understand the correlation among indoor and outdoor pollutant. At kerbsite all the pollutants were highly correlated, whereas at the rest of the sites a mixed correlation was observed depending upon the site. This study indicated that vehicular emission source which operates close to the ground level has more impacts on household close to the traffic which may affect health exposures. The industrial indoor site was cleanest among all the four sites as it was a high rise apartment with good ventilation. The indoor concentration was higher than outdoor concentration although site selected was supposed to be a control area in Mumbai city. Findings in this study were also compared with other international studies.

2009-A-320-ISES

Source Apportionment Of Indoor Residential Fine Particulate Matter Using Land Use Regression And Constrained Factor Analysis

J. E. Clougherty,1 E. A. Houseman,2 J. I. Levy1; 1Harvard School of Public Health, Boston, MA, 2Center for Environmental Health and Technology, The Warren Alpert Medical School of Brown University, Providence, RI

Introduction Land use regression (LUR) and factor analysis (FA) approaches have been used to examine source contributions to outdoor fine particles (PM2.5). People spend more time indoors, however, and these methods have not been commonly applied to examine indoor and outdoor source contributions to indoor residential concentrations. Methods We collected 3-4 day samples of nitrogen dioxide and PM2.5 inside and outside of 43

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homes in summer and winter, from 2003 to 2005, in and around Boston, Massachusetts. Particle filters were analyzed for elemental carbon, trace element, and water-soluble metal concentrations using reflectometry, X-ray fluorescence (XRF), and high-resolution inductively coupled mass spectrometry (ICP-MS). We regressed indoor constituent concentrations against outdoor concentrations, modified by a ventilation proxy, to estimate the indoor-attributable fraction. We then applied FA, constrained to non-negative loadings, to estimate latent source effects, separately, on total indoor concentrations and the indoor-attributable fractions. Finally, we developed predictive regression models using GIS-based outdoor source terms and questionnaire data for indoor source activities. Results FA on total constituent concentrations reasonably separated outdoor-dominated factors (long-range transport, fuel oil, road dust, diesel) from indoor-dominated factors (indoor combustion, cleaning, resuspension). These results were supported by factors identified in FA of indoor-outdoor regression residuals. Regression models predicting indoor-dominated factors had limited statistical power, but significant source terms corroborated some factor interpretations. Conclusions Though limited in statistical power, factor analysis reasonably distinguished between outdoor- and indoor-dominated source factors. Predictive regression models using indoor and outdoor source terms corroborated our original interpretation of some factors, based on known sources for specific constituents. Our approach provides direction for future studies attempting to characterize indoor and outdoor source contributions to indoor concentrations and exposures for epidemiological purposes.

2009-A-489-ISES

Modeling The Infiltration Of Outdoor PM2.5 Into Residences In The Multi-ethnic Study Of Atherosclerosis And Air Pollution (Mesa Air)

R. Allen,1 S. Adar,2 M. Cohen,2 C. Curl,2 T. Larson,2 S. Liu,3 L. Sheppard,2 J. Kaufman2; 1Simon Fraser University, Burnaby, BC, Canada, 2University of Washington, Seattle, WA, 3University of Basel, Basel, Switzerland

The fraction of the outdoor fine particulate matter (PM2.5) concentration found indoors, or infiltration efficiency (Finf), varies between residences and over time within residences. Because individuals spend the majority of time indoors, it may be important to account for this variation in Finf when assessing exposure in epidemiologic studies. However, few studies have considered Finf, primarily because collecting indoor and outdoor residential measurements among large populations is typically not feasible. We used a model-based approach to estimate Finf for over 6,000 participant homes in the Multi-Ethnic Study of Atherosclerosis and Air Pollution (MESA Air), an ongoing investigation of chronic PM2.5 exposure, subclinical cardiovascular disease, and clinical cardiovascular events in eight U.S. communities. We collected two 2-week PM2.5 filter samples, in two different seasons, indoors and outdoors at approximately 50 non-smoking

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homes in each community using 1.8-lpm inertial impactors. Teflon filters were analyzed for elements via X-ray fluorescence, and the indoor/outdoor sulfur ratio was used to estimate Finf. Information on potential predictors of Finf was obtained via questionnaire for the full cohort. City- and season-specific models of Finf were constructed via stepwise multiple linear regression based on housing characteristics, participant behaviors, meteorology, and geographical predictors. Based on preliminary paired indoor-outdoor particulate sulfur measurements (249 2-week samples from 204 homes), community-average Finf ranged between 0.53 ± 0.17 in Baltimore, MD and 0.81 ± 0.16 in New York, NY. Finf was generally higher in the warmer months. Model performance varied between communities, with model-based R2 ranging between 54% in Los Angeles and 71% in Chicago. The most consistent predictors of Finf were the frequency of window opening, air cleaner usage, and outdoor temperature. These preliminary models show promise for estimating Finf among large groups of homes, which may provide more accurate exposure estimation in epidemiologic studies of chronic PM2.5 health effects.

2009-A-282-ISES

The Longitudinal Dependence Of Indoor PAH Concentration On Outdoor PAH And Traffic Volume In An Urban Residential Environment

R. deCastro,1 P. N. Breysse,2 T. J. Buckley,3 L. Wang,2 J. N. Mihalic,2 A. Geyh2; 1Westat, Rockville, MD, 2Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 3Ohio State University School of Public Health, Columbus, OH

The influence of traffic volume and ambient outdoor PAH on indoor PAH exposure was quantified at the Baltimore Traffic Study site, an unoccupied attached 2nd-floor apartment in an inner-city neighborhood “hot spot" surrounded by urban roadways that together carry over 150,000 vehicles per day. Monitoring of outdoor and indoor particle-bound PAH and traffic volume was conducted continously for 12 months at 10-minute intervals (n = 52,560). Time-series modeling accounted for complex and extensive autocorrelation. Vehicle count (0.57 [±SE=0.04] ng/m3 per 100 vehicles every ten minutes) and outdoor PAH (0.16 [±0.001] ng/m3 per ng/m3 outdoor PAH) are statistically significant predictors of indoor PAH, in addition to a mean background indoor exposure without indoor sources of 9.07 ng/m3. Spring 2003 (9.99 [±0.67] ng/m3) and Summer 2003 (9.27 [±1.27] ng/m3) are associated with the greatest increases in indoor PAH, relative to Summer 2002. An additional 1.64 [±0.27] ng/m3 is attributable to work days. Winds from the SW-S-NE quarter, which would have entrained PAH from Baltimore’s densely trafficked central business district and a nearby interstate highway, contribute significantly to indoor PAH (0.31 - 1.16 ng/m3). Dew point, outdoor temperature, and wind speed are also statistically significant predictors. Indoor PAH’s short-term autocorrelation is ARMA[3,3], where lag 3 indicates that PAH concentrations are correlated for up to 30 minutes. Significant autoregressive correlation at lags 144 and 1008 indicate autocorrelations at diurnal and weekly cycles, respectively. In a separate

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time series model, it was established that outdoor PAH itself depends at a statistically significant on vehicle count at a rate of 3.17 [±0.11] ng/m3 per 100 vehicles every ten minutes. Conclusion: local indoor & outdoor exposure to PAH from mobile sources is substantially modified by meteorologic and temporal conditions, including atmospheric transport processes. PAH concentration also demonstrates statistically significant autocorrelation at several timescales.

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Platform

W-PL301: Occupational Exposure Assessment

2009-A-461-ISES

Integration Of Environmental Exposures Into The Traditional Job Exposure Matrix Model: The Job And Environmental Exposure Matrix

J. Gomes,1 L. Zhao2; 1McLaughlin Centre for Population Health Risk Assessment, University of Ottawa, Ottawa, ON, Canada, 2University of Ottawa, Ottawa, ON, Canada

The ideal method for assessing occupational or environmental exposures in epidemiological studies is quantitative measurement of external dermal or environmental concentrations or internal body tissue or fluid doses. However, the ideal is not always practical or possible to achieve and proxy measures of exposure are necessary. The job exposure matrix (JEM) is a type of proxy measure of exposure that converts information on jobs into information on potential exposures. A major design limitation of the JEM is a lack of consideration for exposures that occur outside of the work environment. Therefore, the purpose of this study is to develop a new exposure matrix called the Job and Environmental Exposure Matrix (JEEM) that considers occupational, extra-occupational, and residential exposures with the rationale that both occupational and environmental exposures may contribute to disease outcomes. The JEEM is composed of two components, occupation and environment, and each component is assessed along three dimensions: 1) type of work/extra-occupational activity/residence; 2) intensity and type of exposure; and 3) duration of exposure. The likelihood of exposures to predetermined chemicals is assessed a priori by industrial hygienists using standard job titles and descriptions (National Occupational Classification) and supplemented with self-reported task and exposure information collected from the JEEM specific questionnaire. The JEEM allows for the estimation of lifetime occupational and environmental exposures to chemicals or other substances. Job and environmental exposure indices are computed from their respective three-dimensional inputs and these exposure indices can be used to calculate risks. The addition of an environment criterion to the traditional JEM model allows for an additional dimension to explore the relationship between exposure and disease development.

2009-A-468-ISES

Personal ExposureTo And Area Concentrations Of 27 Metals Associated With Airborne Particulate Matter Measured At The World Trade Center Disaster Site During October 2001 And April 2002

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A. S. Geyh,1 J. Ross,2 J. Herbstman,3 D. L. Williams,1 J. M. Symons,4 S. Eftim,1 P. N. Breysse,1 S. N. Chillrud2; 1Johns Hopkins School of Public Health, Baltimore, MD, 2Lamont-Doherty Earth Observatory Columbia University, Palisades, NY, 3Columbia Univesity Mailman School of Public Health, New York, NY, 4E.I. du Pont de Nemours and Company, Newark, DE

When the World Trade Center (WTC) in New York City (NYC) was destroyed September 11, 2001 an estimated 1.8 million tons of debris was created. Materials that contributed to the debris matrix likely included concrete, steel, asbestos, plastics, solvents, insulation materials, glass, paint, and asphalt. When the clean up operation began hundreds of workers were at potential risk for acute and chronic health effects related to inhalation exposure. The presence of metals at elevated levels was of specific concern as many metals found in building materials and electronic equipment have well understood health effects. October 2001 and April 2002 a study was conducted to assess personal exposure to and area concentrations of airborne particles (Total Dust (TD); PM2.5). The study population included truck drivers. Area monitoring was conducted at the site perimeter and in the debris field. Samples were collected across work shifts both during the day and at night. Personal and area samples were analyzed for 27 metals by HR-ICP-MS. During October average perimeter metal PM2.5 concentrations were typically lower than concentrations in the debris field (e.g. Cr 15.4 vs 83 ng/m3; Pb: 810 vs 1990 ug/m3). For most metals, area concentrations were higher during October as compared to NYC 1999 concentrations, but became more similar by April, except for metals like Ni, V, and La, which showed no difference from NYC levels in either month. Personal exposure was higher during October. Principal components analysis resulted in the following factor (F) loadings: F1 (Sb Cd Ca Cs K Ag S Tl Sn Zn); F2 (As Cr Co Cu Fe Mn Ni) ; F3 (Al Be Mg Sc Na Ti),; F4 (Se V) and F5: (La). Factors were interpreted to represent incineration of building contents/materials, emissions from steel cutting, resuspension of building dust, and regional sources of fossil fuel emissions

2009-A-242-ISES

A Biological Monitoring Guidance Value For Isocyanates And Its Application

J. Cocker, K. Jones; Health & Safety Laboratory, Buxton, United Kingdom

Aims & Methods Historically, workers in the UK motor vehicle repair (MVR) industry were eighty times more likely to get isocyanate-induced occupational asthma than any other group. Control of exposure relies on air-fed Respiratory Protective Equipment (RPE) and the use of spray booths or rooms. Because of the reliance on RPE, biological monitoring is a useful tool in assessing exposure and the effectiveness of control. In 2004, as part of the Health & Safety Executive’s (HSE’s) Disease Reduction Programme a series of visits were made to MVR premises looking at exposure controls and collecting urine samples. The data generated were used to derive a biological

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monitoring guidance value (BMGV) based on good occupational hygiene practice. The BMGV was publicised as part of the continuing initiative in a series of “Safety & Health Awareness Days” (SHADs) that involved body shop managers, paint sprayers, HSE inspectors, trade associations, and occupational health providers. Free biological sampling kits were given to participants to stimulate adoption of monitoring and assessment of controls. Results In 2005, a BMGV of 1 μmol/mol creatinine was adopted by HSE based on the 90th percentile of data from workplaces with good control. Data from the SHADs showed that results were significantly lower than the BMGV (90th percentile 0.7 μmol/mol creatinine (n=444) compared to the BMGV. In 2007, a total of 1902 workers were monitored for isocyanate exposure. Results from 158 workers (8%) exceeded the guidance value and 35% of these returned a repeat sample. Repeat samples were very significantly lower than the initial results (p < 0.0001) with only one result greater than previously and >80% of second results “not detected”. ConclusionsThe results show that the BMGV and HSE initiatives have reduced exposure to isocyanates in MVR and hence the risk of occupational ill-health.

2009-A-357-ISES

Assessment Of Pulmonary Exposure To Manganese: Uptake Of Metals In Inhaled Welding Fumes Into The Pulmonary System

J. D. Richman, A. S. Geyh; Johns Hopkins Bloomberg School of Public Health, Baltimore, MD

The association between exposure to airborne manganese (Mn) and neurotoxic outcomes has been understood for over a century. However, the association between airborne Mn exposure and Mn uptake from the pulmonary system remains unclear. The goal of our study is to identify the time course of uptake of metals into the pulmonary system following inhalation exposure. We selected welding fume as a source of inhalation exposure and exhaled breath condensate (EBC) as a marker of exposure. Baseline samples of EBC were collected from 21 participants, participants welded, then EBC samples were collected 9 more times within 7 days. The sampling strategy was similar in 9 control participants who did not weld. In 10 particle samples analyzed to date, the average Mn concentration is 107 µg/m3 (range 4-700 µg/m3). Preliminary TEM analysis demonstrates that the count median diameter of particles is approximately 10 nm (range 3-200 nm). Mn loading is not evenly distributed and Mn is found mostly as Mn2+. Four trends of Mn EBC concentrations of welding participants are apparent: 1) no measured peak (n=10); 2) a peak immediately following the welding exposure that returns to baseline within 24 hours (n=5); 3) a delayed peak that increases 24 hours following welding exposure and returns to baseline within 72 hours (n=4); and 4) both an early and a delayed peak (n=2). Peak Mn concentrations range from 4-30 µg/L. Out of 10

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participant’s samples, there is no correlation between peak Mn EBC concentrations and Mn exposure concentrations. The varying patterns of Mn EBC indicate that the timing of biomarker collection in Mn exposure studies could significantly affect the results. Differences in elimination could either be due physiological or exposure determinants. We are continuing to characterize the participants’ particle samples in order to assess exposure differences.

2009-A-497-ISES

Comparison Of Dosimetry-based Exposure Predictions And Biomonitoring Results In Chlorpyrifos Handler Studies From Phed

J. C. Kissel, E. J. Tanenbaum, J. H. Shirai; U. of Washington, Seattle, WA

Evaluation of exposure models by comparison to biomonitoring results is essential to the progress of exposure science. However, the number of studies in which exposure measurements adequate to permit estimation of total exposure and concurrent biomonitoring data were both collected is limited. In 2007 EPA revisited selected studies submitted by pesticide registrants to compute ratios of doses estimated from dosimetry to those estimated from biomonitoring and found results both less than (i.e., representing under-prediction by dosimetry based models) and greater than one (i.e., representing over-prediction). While lumping of all cases in the EPA analysis might lead to a general impression that under-prediction of handler pesticide exposure is no more likely than over-prediction, that conclusion is more tenuous on a compound specific basis. Eight PHED chlorpyrifos studies encompassing 165 volunteers classified as mixer/loaders, applicators, cleanup workers or scouts have been reexamined. A key parameter in determination of the ratio of predicted to observed dose is the assumed dermal bioavailability. Importantly, assumption that the dermal bioavailability of chlorpyrifos can be conservatively estimated as 3% is clearly not supported by the PHED data. Additional observations include the following: 1) Results presented in registrant studies were not uniformly reproducible. 2) Creatinine adjustments were sometimes made in a manner that amounted effectively to no correction for incomplete collection of urine. 3) Background levels of the chlorpyrifos metabolite TCP in the urine of the volunteers were chronically elevated over general population levels as reported in NHANES. In some cases background levels were so high as to suggest recent high level exposure in contravention of the experimental protocol and sufficient to mask subsequent exposure in the PHED trial. Funding for this activity was provided by NIOSH via the Pacific Northwest Agricultural Safety and Health Center, 5 U50 OH07544.

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Symposium

W-SY301: Integrative Exposure Biology and Computational Toxicology for Risk Assessment - Session B

Understanding the relationships between environmental exposures and health outcomes requires integration of a wide range of factors—extrinsic (e.g. environmental), intrinsic (e.g. genotypic), and mechanistic (e.g. toxicolgic)—to assess risk. Application of modern methods in molecular biology and advanced computational tools provide the potential to understand complex exposure-outcome systems. A new generation of scientific tools, including transcriptomics and high throughput assays, is emerging that can rapidly measure signals from cells, tissues, and organisms following exposure to chemicals. Combined with development of widely accessible databases and advances in computational technologies for efficient analysis of multidimensional data, these tools are facilitating a “paradigm shift” in characterization of human-environment interaction for risk assessment. A reverse-engineering or systems-biology approach for holistic study of environmental disease considers coupled networks that span multiple scales of biological organization. Mechanistic understanding is derived by characterization of these networks and impacts of perturbations due to behavioral and environmental influences. This symposium will present recent advances in integrative exposure biology and computational toxicology for risk assessment. Specifically, it will bring together presentations from a team of computational scientists, with diverse backgrounds in biological, chemical and environmental informatics. Presentations will address multiple elements of the toxicant source-to-outcome sequence including: application of informatics tools for toxicant characterization; integration with individual and population exposure modeling tools; and enhancement of current quantitative risk assessment. The proposed presentations highlight progress towards mechanism-based environmental health risk assessments in a person-oriented framework that accounts for simultaneous exposures to contaminants from multiple media, routes and pathways. Application of such a multidisciplinary environmental systems approach to evaluate exposure and hazard is expected to facilitate development of more accurate, and eventually even “personalized,” risk assessments.

2009-P-572-ISES

Biological Spectra Profile Analysis in Computational Toxicology: Linking the Bioactivities and Molecular Structures of Chemical Datasets

W. J. Welsh; UMDNJ, Piscataway, NJ

Quantitative Structure-Activity Relationship (QSAR) methods are based on the premise that the biological properties of a chemical are implicit in its molecular structure. It

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follows that, by representing each chemical in a database in terms of its structure-based features called molecular descriptors (e.g., MW, logP, Mol Vol), one may establish a QSAR model that correlates variations in molecular structure (as described by these descriptors) with variations in a biological endpoint assuming a common biological mechanism of action. Once validated, the QSAR model can compare and predict values of the toxic endpoint for untested chemicals that share the same “chemical space”. A corollary of this argument is that two chemicals with similar molecular structures (i.e., similar values of molecular descriptors) should possess similar biological activity profiles. Transposing this statement, two chemicals with similar biological activity profiles should possess similar molecular structures. Adapting the concept of biological spectra analysis [AF Fliri et al., PNAS 2005, 102, 261-266], we are exploring regions of “biological space” populated by the ToxCast chemicals as represented by biological descriptors derived from the biological profiles over the panel of protein receptor targets. As with QSAR methods, it becomes possible to compare, cluster and even predict chemicals with similar biological activity profiles. Support for this work has been provided in part by USEPA GAD R 832721-010. This work has not been reviewed by and does not represent the views of the USEPA or its contractors.

2009-P-573-ISES

Integrated Computational Models for Supporting Risk Assessment: Case Studies with Chemical Mixtures

A. F. Sasso,1 K. Krishnan,2 S. S. Isukapalli1; 1Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, NJ, 2University of Montreal, Montreal, QC, Canada

Health risk assessment of chemical mixtures is frequently conducted on the basis of exposure and toxicity information for individual components. Routine application of physiologically-based toxicokinetic (PBTK) models in mixture risk assessment is limited by the availability of the appropriate PBTK models for chemical mixtures, the number of parameters that need to be specified, and the complexity of applying these PBTK models. Case studies addressing these limitations are presented via the application of a previously developed multi-chemical PBTK modeling framework. In the first case study, a PBTK model for a mixture of polychlorinated biphenyls (PCBs) in the rat was reformulated to incorporate a hierarchical treatment of population parameters, and a proposed model for toxic interactions. Assumptions based on the lipophilicity of PCBs significantly reduced the number of model parameters. These parameters were then estimated through the application of a Bayesian Markov Chain Monte Carlo (MCMC) analysis through model-data fusion. In the second case study, further improvements in the performance and applicability of mixture PBTK models are presented through efficient algorithms that identically reproduce the steady-state outputs of PBTK models. Since human exposures to environmental chemicals frequently lead to steady-state conditions, it is pragmatic to develop a tool that provides the steady-state solutions of full PBTK models of mixtures

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by accounting for the nature and magnitude of interactions. A steady-state solution was developed for computing dose metrics (i.e., blood concentration and metabolism rate) during mixture exposures and applied for computing interaction-based hazard index for mixtures of organics (toluene, xylene, ethylbenzene, carbon tetrachloride and tetrachloroethylene). The presentation focuses on the application of these techniques based on sound exposure biology by risk assessors. Support for this work has been provided by USEPA CR-83162501, USEPA GAD R 832721-010 and NIEHS P30ES005022. This work has not been reviewed by and does not represent the opinions of the funding agencies.

2009-P-195-ISES

Toxicogenomics Approaches to Understand the Impact of Prenatal Arsenic Exposure

R. C. Fry; Gillings School of Global Public Health, University of North Carolina at Chapel Hill, Chapel Hill, NC

The long-term health outcome of prenatal exposure to arsenic has been associated with increased mortality in human populations. In this study, the extent to which maternal arsenic exposure impacts gene expression in the newborn was addressed. We monitored gene expression profiles in a population of newborns whose mothers experienced varying levels of arsenic exposure during pregnancy. Through the application of machine learning-based two-class prediction algorithms, we identified expression signatures from babies born to arsenic-unexposed and -exposed mothers that were highly predictive of prenatal arsenic exposure in a subsequent test population. Furthermore, 11 transcripts were identified that captured the maximal predictive capacity to classify prenatal arsenic exposure. Network analysis of the arsenic-modulated transcripts identified the activation of extensive molecular networks that are indicative of stress, inflammation, metal exposure, and apoptosis in the newborn. Exposure to arsenic is an important health hazard both in the United States and around the world, and is associated with increased risk for several types of cancer and other chronic diseases. These studies clearly demonstrate the robust impact of a mother's arsenic consumption on fetal gene expression as evidenced by transcript levels in newborn cord blood.

2009-P-578-ISES

Integrative Source-to-dose-to-effect Modeling for Interpreting Biomonitoring Data in an Exposure Context

P. G. Georgopoulos, S. S. Isukapalli; Environmental and Occupational Health Sciences Institute (EOHSI), Piscataway, NJ

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Mechanistic assessment of health risks associated with environmental factors should be pursued through the study and elucidation of the cascade of events and processes involved in the “environmental health sequence” from “source” (e.g. the release of a “stressor”, such as a chemical, radiological, or biological agent in an environmental medium) to “outcome” (e.g. development of an environmentally caused disease). This requires an integrated approach for assessing the interactions of environmental and biological systems across multiple scales of spatiotemporal extent and biological organization. A computational framework is presented here that incorporates a wide range of diagnostic and prognostic modeling methods for “forward” source-to-dose exposure modeling as well as for interpretation of biomarker data in an exposure context. The forward modeling includes components for population exposures and Physiologically Based Toxicokinetic (PBTK) modeling, while the “reverse” modeling includes numerical “inversion” techniques in conjunction with PBTK modeling and complimentary exposure-related data. Several inversion techniques are studied, including biomonitoring equivalents, direct deconvolution, exposure conversion factors, and Bayesian Markov Chain Monte Carlo technique. Example case studies are presented that focus on exposures to chemicals in the USEPA’s ToxCast database. This framework allows for the identification of major gaps in databases and techniques for interpreting population biomonitoring data and for reconstructing exposures from biomonitoring data, thus providing input towards improved designs for future biomonitoring studies. It also facilitates mechanism-based environmental health risk assessments in a person-oriented framework, which accounts for simultaneous exposures to contaminants from multiple media, routes, and pathways. Support for this work has been provided by USEPA CR-83162501, USEPA GAD R 832721-010 and NIEHS P30ES005022. This work has not been reviewed by and does not represent the opinions of the funding agencies.

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Symposium

W-SY302: The Validity and Reliability of Urinary Metabolites as Exposure Biomarkers

Pesticide metabolites measured in urine are commonly used to assess human exposures to parent pesticides including organophosphorus (OP) and pyrethroid insecticides. Several human observational measurement studies have recently reported concurrent levels of these pesticides and their metabolites, which are also used as urinary biomarkers, in several media such as food, air, dust, and on surfaces at residences and other similar settings in the United States. A number of metabolites of OP insecticides, for example those of chlorpyrifos and diazinon, and of pyrethroids, for example, permethrin, were measurable in the environmental samples including 3,5,6-trichloro-2-pyridinol (TCP), 2-isopropyl-6-methyl-4-pyrimidinol (IMP), and 3-phenoxybenzoic acid (3-PBA), respectively. In addition, toxicology studies have recently shown that laboratory animals orally dosed with these metabolites of OP insecticides absorbed and excreted significant amounts of them unchanged in their urine. This research suggests that humans are exposed to these environmentally-occurring pesticide metabolites in these everyday environments. They are also likely absorbing and excreting a substantial amount of these metabolites unchanged in their urine. This information brings into question the validity and reliability of using urinary metabolites of these pesticides as urinary biomarkers of exposure. Past human observational measurement studies might have therefore overestimated the non-occupational exposures of humans to low levels of pesticides in these settings when relying on their metabolites as urinary biomarkers. In this session, we will present research data and findings from recent human observational measurement studies showing concurrent levels of OP or pyrethroid insecticides and their environmental metabolites in several media at homes and child daycare centers. In addition, research will be presented showing that laboratory animals exposed to OP environmental metabolites absorbed and excreted substantial amounts of them unchanged in their urine.

2009-P-64-ISES

Relative Proportions of Parent Pyrethroids and Degradates Found in Dust Samples During Residential Sampling

J. Starr; USEPA, RTP, NC

Relative proportions of pesticides and their metabolites were determined in samples of indoor dust that had been collected in vacuum cleaner bags during the Children's Total Exposure to Persistent Pesticides and Other Persistent Organic Pollutants (CTEPP) study. The concentrations of 13 selected pyrethroid pesticides and their degradation products

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were measured in sieved vacuum cleaner dust. In total, the contents of 85 vacuum cleaner bags were evaluated and permethrin was found in all samples. Sixty-nine samples contained at least one additional pyrethroid, but none had more than five pyrethroids in detectable concentrations. Excluding permethrin, pyrethroid concentrations were typically less than or equal to 100 ng/g of dust. The majority of degradates were present in more than half of the dust samples, usually at concentrations of less than or equal to 100 ng/g of dust. For those pyrethroids with a characteristic oxydibenzene group, the cyclopropane degradates were present at higher concentrations than the corresponding benzoic acid moieties. Based on this study, the metabolic products of pyrethroids in important exposure media should be quantified to reduce possible overestimation of exposure when urinary biomarkers are used to reconstruct dose. This is particularly relevant when the cyclopropane based moieties are used.

2009-P-65-ISES

Organophosphorous Insecticide Exposure Assessment: Human Urine Biomarkers Are More Persistent In Produce Than Their Toxic Precursors

Y. Li; University of California, Riverside, CA

Dialkyl phosphates (DAPs) and more specific metabolites of organophosphorous (OP) insecticides persist in edible produce and foliage longer than OP insecticides and their toxic oxons. Malathion applied at 1 or 2 #/A rates to commercial strawberries produces trace OP residues that are well below regulatory tolerance at the preharvest interval (PHI, 3 days) and undetectable (LOQ 10 ppb) after about 3 weeks. O, O-Dimethyl phosphate and corresponding dithiophosphate are measurable in leaves and strawberries for at least 50 days. Total strawberry DMP, DMTP, and DMDTP at the PHI, 20 d and 50d were 1.4, 0.80 and 3.2 nmol/g, respectively. OP insecticide metabolites are absorbed and excreted readily in urine based upon their physical and chemical properties. Their measurement in human urine, particularly in low-dose, non-occupational studies, does not necessarily indicate OP insecticide exposure since preformed metabolites (in the environment) are more persistent than the parent compounds. A survey of produce harvested from OP treated crops has demonstrated the extensive occurrence of dimethyl and diethyl phosphorous insecticide residues in amounts that could confound low-level exposure assessments. We gratefully acknowledge the cooperation and support of Daren Gee, DB Specialty Farms, Santa Maria, and the California Strawberry Commission.

2009-P-66-ISES

Urinary Biomarkers of Pesticide Exposure: A "Gold Standard" Whose Value is Changing

D. Barr; CDC, Atlanta, GA

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This presentation will include data from several studies that show that environmental degradates of OP insecticides are present in some environmental matrices and contribute to the human urinary concentrations of these measured degradates (which are also metabolites). After controlling for analytical conversion of pesticides into their degradates/metabolites in dust and juice (which has been a criticism of some past studies), we observed degradation of both dimethyl- and diethyl-substituted OP insecticides, with the degradation being more significant in acidic, aqueous-based matrices such a fruit juices. We also conducted animal experiments that indicated that these degradates, if ingested or delivered by injection, were excreted as the intact chemical, thus would likely contribute to an overestimation of exposure using urinary metabolite concentration data. Our data suggest that if exposures are predominantly dietary, which is likely for background exposures, that urinary concentrations will erroneously overestimate exposures; however, in occupational or other acute exposure settings where dietary exposures do not predominate, urinary concentrations may be a reasonable mechanism for beginning to estimate exposures (along with other ancillary data).

2009-P-67-ISES

Human Exposure to Pyrethroid Pesticide Hydrolysis Products in Residential Settings

J. Raymer; RTI International, RTP, NC

This presentation will focus on a study that we conducted that evaluated the potential for exposure to pyrethroid pesticides and their hydrolysis products following indoor application and to investigate potential overestimations of pyrethroid exposures based on biomonitoring data. Environmental (air, dust, wipe, and food) and biological (urine and saliva) samples were collected before and for seven days following home-based application of deltamethrin or a mixture of permethrin and pyrethrins. Biological samples were collected from adult/child pairs in each of three homes. Environmental samples were extracted and analyzed by high performance liquid chromatography in conjunction with tandem mass spectrometric detection both for parent compounds (deltamethrin, permethrin, and pyrethrins) and hydrolysis products (3-phenoxybenzyl alcohol (3-PBOH), 3-phenoxybenzaldehyde (3-PBAl), 3-(2,2-dichloroethenyl)-2,2-dimethylcyclopropane-carboxylic acid (DCCA), 3-(2,2-dibromoethenyl)-2,2-dimethylcyclopropane-carboxylic acid (DBCA), cyclopentenyl alcohols, trans-chrysanthemic acid (TCA), and chrysanthemum dicarboxylic acid (CDCA) monomethyl ester). In biological samples, oxidative metabolites were measured (3-PBA, DCCA, DBCA, CDCA, TCA). Results showed measurable concentrations of the analytes in most media, although the recoveries of the halogenated acids were generally poor. The neutral hydrolysis products represented a relatively small fraction (approximately 3%) of the total measured parent compounds. However, these analytes have significantly higher vapor pressures than the parent pyrethroids or free acid hydrolysis products and thus represent a greater fraction of the pesticide-related compounds in air. Parent pesticides

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measured in air most likely are associated with trapped, suspended dust. This could result in increased exposure to the hydrolysis products via the inhalation route.

2009-P-68-ISES

Exposures of Preschool Children to Organophosphate Pesticides and Their Urinary Biomarkers

N. Wilson; Battelle, Durham, NC

The aggregate potential exposures to the organophosphate (OP) insecticides chlorpyrifos (CPF) and diazinon (DZN), and their degradation products 3,5,6-trichloro-2-pyridinol (TCP) and 2-isopropyl-6-methyl-4-pyrimidinol (IMP) were compared to the excreted amounts of TCP and IMP in urine for 101 preschool children in 50 North Carolina households. Multimedia samples of indoor and outdoor air, dust, and soil in each household, and of solid food eaten and hand surface residue for each child, were collected annually over 24 hr, along with urine –a first morning void or an overnight diaper for each child. Over three years, 2003-2005, the children’s aggregate exposures to both CPF and DZN declined, as did their exposures to TCP and IMP. When the potential intake doses were compared to the excreted doses of the TCP and IMP urinary metabolites, the excreted amounts were much higher than could be accounted for by the aggregate potential intake doses of the parent pesticides alone. For chlorpyrifos, when the aggregate potential doses of CPF and TCP, taken together, were compared to the urinary excreted doses of TCP, most of this discrepancy disappeared. For all the children over all three years, the geometric mean molar ratio of the aggregate potential dose to the excreted dose of metabolite, (CPF+TCP)/TCP, was 0.87. For the older sibling in a household this ratio was 0.97, and for the younger sibling it was 0.76. That is, essentially all of the excreted TCP were accounted for by the intake of CPF and TCP together. However, the data for DZN and its metabolite/degradation product are still puzzling, with the urinary IMP far exceeding the potential intake of DZN and IMP together. Further investigation is needed to determine the conditions under which IMP and other potential urinary biomarkers are reliable indicators of exposure to their parent compounds.

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Platform

W-PL302: Local and Regional Exposure Issues

2009-A-262-ISES

The Impact Of Oil On The Health Of Populations Living Near Oil Fields

A. Tabaku,1 S. Bala,2 E. Petrela1; 1Public Health Institute, Tirana, Albania, 2University Hospital for Lung Disease, Tirana, Albania

Background: Exposure of populations living near oil fields to oil fumes and gases leads to effects on nervous and respiratory systems, as well as cancers of multiple sites. Material and methods: We conducted a study consisting of an exposed group including 233 adults living in areas near oil fields, and one group of control 209 adults who lived at the distance of 25 km from the oil field. We selected households through systematic sampling and interviewed two persons in each household, about symptoms relating to eyes, respiratory disease, skin and nervous system, smoking, allergies, beliefs about the effect on their health and anxiety about the health effects. Statistical processing of the results was carried out by using SPSS 14 package. Results: Living in areas exposed to the crude oil was significantly associated with higher anxiety and depression scores, worse mental health and pulmonary health; and self reported dull headache OR 2.27 (95% CI 1.68 - 3.07), sore eyes OR 1.60 (95% CI 1.29 - 1.98), itchy eyes OR 1.82 (95% CI 1.1.47 - 2.25), puffy eyes OR 1.25 (95% CI 1.04 - 1.50) and dry throat OR 1.69 (95% CI 1.34 - 2.12), respiratory attacks OR 1.14 (95% CI 0.93 - 1.34) after adjusting for age, sex, smoking status, anxiety, and the belief that oil had affected health. Inhabitants living in exposed areas reported higher rates of physical and psychological symptoms than control areas. Symptoms significantly associated with exposure after adjustment for anxiety and health beliefs were those expected from the known toxicological effect of oil, suggesting a direct health effect on the exposed population. Conclusion: Results suggest that the occurrence of increased symptoms and pulmonary diseases among the exposed group is more likely to be due to exposure to the crude oil.

2009-A-601-ISES

Exposure To Inhalable Lead And Artificial Turf Fields

S. L. Shalat, K. Black, A. Stambler, H. O. Emoekpere, M. Hernandez; E.O.H.S.I., Piscataway, NJ

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In recent years ethical concerns have complicated the ascertainment of young children’s exposure to environmental toxins. In order to alleviate these ethical conflicts of exposing young children to even commonly present household toxins a robotic surrogate has been developed. The Pre-toddler Inhalable Particulate Environmental Robotic (PIPER) sampler is an autonomous platform capable of mimicking children’s floor and ground activities so that exposure data relevant to young children may be safely collected. For outdoor sampling a GPS module allows the designation of sampling area. Two samplers can be accommodated at one time, including a 10 l/min air sampling pump for the collection of gravimetric or qualitative samples. Additionally, PIPER is equipped with a spring load base plate that allows the attachment of either clothing of artificial skin, thus allowing air sampling for inhalation exposures and transfer of toxins to be obtained simultaneously, without a child being present. Using this technology a study has been carried out of exposure to metals on artificial turf athletic fields. This study has found not just elevated lead levels from wipe samples as others have previously noted, but also inhalable lead particulate when the surface is disturbed by the passage of the PIPER robot. The levels of inhalable lead observed from the PIPER samples ranged from just under 4 to greater than 10 times higher than simultaneous stationary measurements. The significant elevation of lead levels on artificial turf fields caused by the small 20 pound robot raises concerns for the hazard inhalation of lead may pose to groups of children engaged in team sports on artificial turf fields.

2009-A-366-ISES

Assessment Of Transport Emissions Impact On Human Health (Case Study Of Zaporizhia)

O. Voznyuk,1 O. Turos,1 O. Kartavtsev,2 A. Petrosian,1 L. Chernenko3; 1State Institution Marzeev Institute of Hygiene and Medical Ecology Academy of Medical Sciences of Ukraine, Center of Environmental Health and Risk Assessment, Kyiv, Ukraine, 2State Institution Marzeev Institute of Hygiene and Medical Ecology Academy of Medical Sciences of Ukraine, Kyiv, Ukraine, 3State Enterprise Center of Register for State Sanitary and Epidemiologic Service of Ukraine, Kyiv, Ukraine

Introduction. The impact of transport-related air pollution is among the leading concerns about air quality in many European countries and in Ukraine these days. Objective. The research was aimed at human health risk assessment from transport-related air pollution near nine most hardly loaded city crossroads in Zaporizhia (Ukraine). Materials and methods. Methods: computer modeling (program complex CALRoads Viev v.3.8.0, Lakes Environmental Software Group), human health risk assessment methodology (EPA). Input data: - roads characteristics (number of lines, road width, crossroads parameters) and traffic intensity (transport flow intensity and structure, speed regime, time of breaks) data - prepared in cooperation with Zaporizhia National Technical University; - digital relief model;

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- digital city map on which crossroads were located; - meteorological data for one full year observations (station UKDE 34601) that was preprocessed to compatible with CALRoads View requirements format. Results. Average diapasons of concentration for following emission compounds were defined on the results of separate calculations for each crossroads: CO 0,08-2,78 mkg/m3, NO2 0-0,118 mkg/m3, CxHy 0-0,79 mkg/m3, PM10 0-7,7 mkg/m3, benzpyrene 0,00003-2,46 mkg/m3. The received concentrations for all chemicals, except PM10, exceed the meaning of reference concentrations. Cancer and non-cancer risk were estimated. Non-cancer risk were within diapasons: CO HQ=0,038÷2,34; NO2 HQ=0,49÷2,94 (medium level). Non-cancer risk for carbohydrates was not estimated due to substance complex nature. Individual cancer risk during the lifetime for benz(a)pyrene was at level 10-4 - 10-3 (quite high index) and for PM10 - 10-7- 10-5(acceptable but demands periodic control according to WHO). Conclusion. Human exposure to transport-related air pollution near nine selected crossroads of Zaporizhia was estimated. This enabled the assessment of cancer and non cancer risk levels of five registered pollutants for the population living on the adjacent territories and to rank crossroads by their impact.

2009-A-602-ISES

Soil Heavy Metals And Their Human Exposure Risks In Coal Fields Of Dhanbad, India

R. E. Masto, L. C. Ram, V. A. Selvi, J. George, R. C. Tripathi, N. K. Srivastava; Central Institute of Mining and Fuel Research (Digwadih Campus), Jharkhand, India

Contamination of soil is of concern for human health and ecosystem function. Quantification of soil quality and health hazard is complicated by the fact that soil is not directly consumed by human and animals as are air and water. Coal mining is one of the core industries that contributes to the economic development of a country but deteriorate the environment. The soil pollution problem in coal fields is too extensive to be solved and accordingly site specific risk assessment is needed to set priorities for reclamation. In order to assess the risk of adverse health effects on human exposure to heavy metals, soil samples were collected from different locations in the coal based industries (coal beneficiation plant, open cast mines including fire affected areas) of Dhanabad district, Jharkhand, India. Samples were collected from a control site also. Epidemiological health survey was conducted at both the control and industrial sites. A high level of Ni, Cr, Co, Cu, Pb, and V was observed in contaminated soils than the control. The metal exposure for the residents of the coal field was calculated solely based on soil ingestion exposure pathway. The levels of metals in these soils are below the threshold exposure limits. The soil enzymes like dehydrogenase, phenol oxidase and peroxidase were significantly decreased in contaminated soils, whereas the catalase and soil respiration rates were higher in contaminated sites. These soil microbial properties could be considered as bioindicators for risk assessment. The prevalence of diseases like asthma, arthritis, high

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& low blood pressure, and skin disorders are more among the inhabitants of industrial site than control. Morbidity rate was higher in contaminated sites for hair loss, tooth problems, blurred vision, chest discomfort, loose motion, reduced heat tolerance, muscular pain, and cracked foot.

2009-A-348-ISES

Pm2.5 Source Apportionment Following A Large Woodstove Changeout Program In Libby, Montana

T. Ward; The University of Montana, Missoula, MT

PM2.5 Source Apportionment Following A Large Woodstove Changeout Program in Libby, Montana Tony J. Ward*1, Christopher P. Palmer2, and Curtis W. Noonan1 1Center for Environmental Health Sciences, The University of Montana, Missoula, Montana; 2Department of Chemistry, The University of Montana, Missoula, Montana. Abstract Prior to a community-wide woodstove changeout program, a Chemical Mass Balance (CMB) source apportionment study was conducted in Libby, Montana during the winter of 2003/2004 to identify the sources of PM2.5 within the valley. Results from this study showed that residential woodstoves were the major source, contributing approximately 80% of the ambient PM2.5 throughout the winter months. In an effort to lower the ambient PM2.5, a large woodstove changeout program was conducted in Libby from 2005 to 2007, where nearly 1,200 old polluting woodstoves were changed out with cleaner burning models. During the winter of 2007/2008, a follow-up CMB source apportionment study was conducted to evaluate the effectiveness of the changeout. Results from this study showed that average winter PM2.5 mass was reduced by 20%, and woodsmoke related PM2.5 (as identified by the CMB model) was reduced by 28% when compared to the pre-changeout winter of 2003/2004. These results suggest that a woodstove changeout can be an effective tool in reducing ambient levels of PM2.5 in woodstove impacted communities.

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Interactive Poster

W-IP301: Indoor Air

2009-A-278-ISES

Assessing Personal Exposure To PM2.5 From Secondhand Smoke In 36 California Indian Casinos

R. Jiang, K. Cheng, V. Acevedo-Bolton, W. Ott, N. Klepeis, L. Hildemann; Stanford University, Stanford, CA

Although California was the first state to eliminated smoking in most indoor public places in 1994, exposure to secondhand smoke still occurs in California’s 58 Indian casinos. However, few measurements were available of personal PM2.5 exposures in casinos. In this study, we have characterized exposure levels in 36 California casinos, exploring differences based on casino size, microenvironments, and the levels of smoking. 36 casinos (35 smoking and 1 smoke-free) were randomly selected to maintain high geographical coverage in California, and to proportionately represent large, medium and small sized facilities. For each casino visit of 1 to 3 hours, two or more investigators carried concealed real-time monitors and measured personal PM2.5 exposure in a series of microenvironments, including the outdoors, the slot machine area, the nonsmoking slot machine area, the restaurants, and etc. Time activity diaries were maintained at 5-minute interval. For comparison, 8 casinos in Reno, Nevada were monitored using the identical protocol. The mean PM2.5 exposure level for the smoking sections in casinos sampled in California was 67 micrograms/m3, ranging from 18 to 173 micrograms/m3. This average was 9 times as high as the average level measured outdoors, 3 times as high as the nonsmoking sections indoors, and 2 times as high as the restaurant levels. In 94% of the samples, the average exposure level in the casino smoking area exceeded the EPA 24-hour PM2.5 Standard of 35 micrograms/m3. For the nonsmoking gambling areas, three methods were seen for separating the space from the smoking areas - the type of method used greatly influenced how much lower the PM2.5 exposure levels were. The smoke-free casino had personal PM2.5 exposure levels that were more than an order of magnitude lower than the average for the casinos that allowed smoking.

2009-A-287-ISES

Development And Evaluation Of A Modeling Framework For Transport Of Soil Contaminants To The Indoor Environment

P. I. Beamer, M. Kelly, D. W. Layton; University of Arizona, Tucson, AZ

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Improved methods are needed to assess exposure pathways for soil contaminants that can be present in mine tailings, land applied bio-solids and at Superfund sites. Although these contaminants originate outdoors, they may be tracked into homes where people spend a majority of their time. We need improved understanding of outdoor soil contaminants migration to indoor environments and their contribution to dust contamination. We developed a soil contaminant-transport modeling framework to predict concentration of outdoor soil contaminants in house dust. The model accounts for: (a) tracked-in soil particles, (b) deposited dust from infiltration of outdoor air particles, and (c) organic matter (OM) produced indoors. Floor dust is removed by cleaning and airborne exfiltration of floor particles resuspended into indoor air. A large portion of resuspended particles are recirculated into household dust fall. We completed field measurements of OM and soil-derived crustal elements (i.e., Al, Si, Mn, and Ti) to evaluate the model and obtain key parameter inputs. Although many of the necessary parameters can be obtained from the experimental literature and field measurements, a few (i.e., flux of indoor OM to floor surfaces, resuspension floor particles, and building shell penetration) must be derived from appropriate model simulations. We obtained soil, house dust, dust fall, indoor and outdoor air samples from 10 households in a community concerned with contamination from nearby mine tailings. All samples were analyzed for OM content by ignition and metals using ICP-MS. Model calculations indicate that outdoor air particles penetrating the building shell can account for a significant portion of soil contaminants in house dust. These results indicate that soil remediation efforts at hazardous waste sites must specifically address aeolian resuspension of outdoor soil contaminants due to their significant contribution to the indoor environment. Soil re-vegetation and stabilization measures may represent a more cost-effective and improved intervention strategy.

2009-A-293-ISES

Effect Of Range Hood On Exposure To Ultrafine Particles From Gas Stoves

D. Rim; The National Institute of Standards and Technology, Gaithersburg, MD

Gas stoves are one of the most common combustion sources of ultrafine particles (UFPs) in residential buildings. UFPs have been observed to be associated with adverse respiratory and cardiovascular effects among susceptible individuals in the population. The objective of the present study is to investigate the effect of using a kitchen range hood on exposure to UFPs from gas stoves. The experimental measurements were conducted in a manufactured house (volume of 340 m3). Using a Scanning Mobility Particle Sizer (SMPS), UFPs ranging from 2 nm to 64 nm in size were monitored in a bedroom and kitchen. The average measured flow rate through the range hood was 65 cfm, indicating that the flow through the hood in a manufactured house is in relatively low range. The UFP size distributions produced by the gas flame alone (no pots) and boiling water were characterized with the hood on and off. Peak concentrations ranged from 70,000 cm-3 to 370,000 cm-3 with hood off, and from 40,000 cm-3 to 300,000 cm-3 with hood on for particles from 2 nm to 30 nm with 90 %

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of particles below 20 nm. The range hood was only effective for the removal of UFP larger than 15 nm. With regard to UFP smaller than 15 nm (which constituted 60 % to 90% of the total), very small or no change in particle number was observed with the kitchen hood operating. This may be explained by the strong particle diffusion for UFP smaller than 15 nm, which causes the particles to transport out of the thermal plume from the flame. The tests with the gas flame alone produced more UFPs smaller than 15 nm compared to those with boiling water, implying that the presence of the boiling pot contributes to particle coagulation and produces larger particles.

2009-A-383-ISES

Predictors Of Indoor Air Pollutants In Residences In Regina, Saskatchewan, Canada

A. J. Wheeler,1 N. Clark,1 Y. Graff,2 M. MacNeill,1 M. Héroux1; 1Health Canada, Ottawa, ON, Canada, 2Regina Qu'Appelle Health Region, Regina, SK, Canada

Health Canada and Regina Qu’Appelle Health Region measured residential indoor and outdoor air for particulate matter (PM2.5, PM10-2.5), nitrogen dioxide (NO2) and ozone (O3). During the winter and summer of 2007, 106 and 111 participants, respectively, were recruited with 71 homes participating in both seasons. Homes were recruited by stratified sampling on the basis of their main heating system, as well as year of construction. Detailed questionnaires were completed by an adult occupant to identify any housing characteristics and occupants’ activities which may influence the sampled pollutants’ concentrations. Air pollution monitors were deployed inside the participant’s home (typically in their living room) and in their backyard for 5 days in each season to capture both indoor and outdoor exposure levels. Mean concentrations during the winter and summer were 9.42±13.46µg/m3 and 9.51±12.21µg/m3 for PM2.5, and 4.09±2.28µg/m3 and 5.06±3.02µg/m3 for PM10-2.5. Valid measures for NO2 and O3 were only available in the summer with means of 6.36±5.22ppb and 1.32±1.53ppb respectively. Predictors of indoor concentrations were investigated using housing characteristics and occupants activities using multivariate regression models. Separate analyses were performed for each season. Thirty-four homes had environmental tobacco smoke (ETS) exposure from either an occupant or visitor during sampling, as such, predictor models were developed for all homes and for all non-smoking homes separately. Preliminary results for all homes indicate that 55% and 45% of the variability of indoor PM2.5 was explained for winter and summer respectively; in both seasons important predictors included smoking in the home and outdoor PM2.5. In non-smoking homes for both seasons, about 24% of the variability of indoor PM2.5 was explained; important predictors included outdoor PM2.5 levels, as well as candle burning and window opening (in summer), and presence of furnace air cleaning devices (in winter). Results from the other pollutants will be reported.

2009-A-271-ISES

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Air Pollution Exposure Model For Individuals In Health Studies: Evaluation Of Residential Indoor Air Quality Model For Particulate Matter

M. S. Breen, M. Breen, T. C. Long, R. W. Williams, B. D. Schultz; U.S. Environmental Protection Agency, Research Triangle Park, NC

Air pollution epidemiologic studies have observed associations between ambient concentrations of particulate matter (PM) and reported rates of morbidity and mortality. These studies often use measurements from central-site ambient monitors as exposure surrogates. To better understand the relationships between ambient concentrations and individual exposures, we are developing an air pollution exposure model for individuals (EMI) in health studies to predict personal exposures from ambient concentrations and questionnaire information such as building characteristics, indoor sources, and time-activity data. A critical aspect of the EMI is estimation of PM concentrations within individual homes where people spend most of their time. We developed a mass-balance residential indoor air quality (IAQ) model to predict daily total and apportioned (ambient and nonambient) indoor PM2.5 mass concentrations from outdoor concentrations and questionnaires. The air exchange rate (AER), a critical model parameter, was estimated using a mechanistic AER model that predicts daily AER for individual homes from historical questionnaires and meteorology. Other parameters were either set to reported literature values or estimated using questionnaire data and measurements from the Research Triangle Park (RTP) Particulate Matter Panel Study. The RTP study measured daily residential AER and personal, residential indoor, residential outdoor, and ambient PM2.5 mass concentrations for seven consecutive days during each of four seasons in 36 homes within the RTP area of North Carolina. For the AER model, median difference between individual model-predicted and measured AER was 41.7% (0.21 hr-1). For the IAQ model, median difference between model-predicted and measured total indoor PM2.5 mass concentrations was 33.6% (4.0 µg/m3). Our study demonstrates the feasibility of coupling an AER model with an IAQ model to predict individual indoor PM2.5 concentrations in support of model-based exposure assessments in health studies. This work was reviewed by the U.S. EPA and approved for publication but does not necessarily reflect Agency policy.

2009-A-456-ISES

Formaldehyde And Other Volatile Organic Chemical Emissions In Four Temporary Housing Units

R. Maddalena, M. Russell, D. P. Sullivan, M. G. Apte; Lawrence Berkeley National Laboratory, Berkeley, CA

Indoor concentrations of thirty-three volatile organic chemicals were measured in four unoccupied temporary housing units (THUs) belonging to the U.S. Federal Emergency Management Administration (FEMA). The highest level contaminants in the THUs were formaldehyde, acetic acid and TXIB (a plasticizer used in vinyl flooring) with median

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concentrations of 440, 425 and 36 ppb, respectively. A number of VOCs were higher than published concentrations in other dwellings and several exceeded previously measured whole-building emission rates for new buildings by over a factor of five. Individual materials were collected from the THUs and emission factors were determined using small chambers to identify the potential source of indoor contaminants. The individual materials were grouped by material type and emissions were used to derive exposure concentrations for comparison to reference values. Using material loading factors and ventilation rates that are relevant to the trailers, all of the material types had at least two chemicals (formaldehyde and nonanal) with derived concentrations in excess of either chronic reference exposure levels or odor thresholds and several of the materials had numerous chemicals where emissions exceeded threshold concentrations. The extensive use of composite wood products and vinyl coverings, combined with low air exchange rates relative to material surface areas, may explain the high concentrations of some VOCs and formaldehyde.

2009-A-479-ISES

Characterization Of Subslab-to-indoor-air Attenuation Factors In The U.S. EPA Vapor Intrusion Database

T. Minegishi, D. MacIntosh, J. Allen; Environmental Health and Engineering, Needham, MA

Vapor intrusion of volatile organic compounds (VOCs) from contaminated groundwater through the soil and into buildings is a recognized public health concern. However, exposure-relevant characteristics of observed vapor intrusion have not been fully explored. Using a subset of VOC concentrations, building characteristics, and soil attributes developed by the U.S. EPA, we examined the magnitude and covariates of subslab-to-indoor-air attenuation factors (subslab AF), a measure of the indoor air concentration arising from intrusion of vapors from subsurface soil. After omitting observations with potential alternative sources of VOCs indoors, the remaining 271 subslab AF values were lognormally distributed with a geometric mean of 5E-03 and ranged that extended from 7E-05 to 6E-01. In a bivariate regression model of log-transformed values, subslab VOC concentrations were significantly (p<0.01) associated with corresponding indoor air VOC levels. In further statistical models, site, soil type and VOC type (p<0.01) explained approximately 37% of the variation in subslab AF, with the site the dominate covariate (28%). For soil type, the larger particle size was associated with the higher subslab AF, suggesting that soil with higher porosity can lead to higher subslab AF. Site specific analyses suggest that building type and physical-chemical properties of the VOCs such as the Henry’s law constant are associated with subslab AF (p<0.01). The significance of Henry’s law constant suggests that the vapor pressure of the VOC, moisture contents of soil, and/or organic carbon content of soil may also be important covariates of vapor intrusion. This analysis of the EPA database identified several exposure-relevant characteristics of the vapor intrusion phenomenon from empirical observations of multiple sites and

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chemicals. Expansion of the EPA database and the inclusion of additional parameters such as organic carbon fraction, soil moisture content and soil density would allow further analyses that could reveal other useful predictors of vapor intrusion.

2009-A-419-ISES

Modeling Personal And Indoor Exposure To Nitrogen Dioxide Among Adults In Eight Swiss Cities In 1993 And 2003

H. C. Phuleria, D. Keidel, A. Ineichecn, M. Y. Tsai, C. Schindler, N. Kuenzli, L. J. S. Liu; University of Basel, Basel, Switzerland

There are growing evidences of associations between adverse health effects and air pollutant concentrations such as nitrogen dioxide based on central site data. Since people spend more than 75% time indoors at home, the associations based on central site/ outdoor measurements are likely prone to exposure missclassification. In fact, Schindler et al. (1998) reported a higher association between lung function and personal NO2 exposure than with outdoor or central-site NO2 concentrations. This study was part of the Swiss cohort study on Air Pollution and Lung Diseases in Adults (SAPALDIA) in which 9,651 subjects (aged 18-60) were randomly sampled from eight geographically diverse areas in Switzerland, with the first health examination conducted in 1991 and a follow-up assessment of 8,047 subjects in 2002. Personal, indoor and outdoor passive NO2 measurements were taken from up to 100 subjects and their residences per area over three seasons in 1993 and indoor and outdoor measurements were repeated in 2003. In 1993, mean personal, indoor and outdoor NO2 levels were 27±13 micrg/m3, 21±12 micrg/m3 and 31±16 micrg/m3, respectively. In 2003, outdoor NO2 levels decreased considerably (25±12 micrg/m3) while indoor NO2 levels were observed similar or slightly lower (18±13 micrg/m3). Highest association was found between personal and indoor NO2 exposures (R2=0.51). We develop multivariate linear regression models to predict indoor exposure to NO2 based on central site concentrations, geographic and meteorological traffic variables and home indoor sources and ventilation characteristics separately for year 1993 and 2003. Similarly, personal NO2 exposure models are constructed for year 1993. Relative impact of indoor sources is also assessed by restricting the analysis to subjects with no reported indoor sources of NO2. All models are constructed for individual areas to examine within city relationships, and pooled together to study across-city variations.

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Poster

W-P001a: Wednesday: Occupational, Water, Pesticides - Theme: Characterizing the Exposure Pathway

2009-A-285-ISES

Spread Of Surrogate Virus And Bacteria In An Aircraft Cabin Simulation Model

H. Hirt, B. Hosni, M. Hosni; Kansas State University, Manhattan, KS

Modern air travel can have a considerable impact on the fast spread of infectious diseases not only by transporting infected persons quickly around the world but also for its potential to spread the infectious agent in a confined space over several hours of trans- and intercontinental flights. As the SARS epidemic and the now just emerging swine flu scare prove, old and newly emerging pathogens can quickly spread all over the world with considerable economic consequences. Case studies of pathogen spread during air travel are rare and systematic studies are hampered by the lack of adequate facilities. The Kansas State University Aircraft Cabin Environment Research Laboratory contains an eleven-row Boeing 767 mock cabin for environmental studies. We performed releases with two surrogate agents, the enveloped Escherichia coli bacteriophage PhiX174 and Lactococcus lactis. Our data indicate a clear zone of high risk around the point of release. Infectious particles and bacteria spread around the whole cabin but at numbers that suggest relative ease of containment. In the case of a one-time release, sampling 45 min after the release did detect only limited numbers of viable bacteria, indicating fast clearance by the cabin’s environmental system.

2009-A-451-ISES

Source To Outcome Microbial Exposure And Risk Modeling Framework

G. Whelan,1 M. E. Tryby,1 J. Soller2; 1U.S. EPA, Athens, GA, 2Soller Environmental, Berkeley, CA

A Quantitative Microbial Risk Assessment (QMRA) is a computer-based data-delivery and modeling approach that integrates interdisciplinary fate/transport, exposure, and impact models and databases to characterize potential health impacts/risks due to pathogens. As such, a QMRA exercise fits well with multimedia modeling paradigms that have been widely exercised in the chemical and radionuclide communities, using software system architectures, like the Framework for Risk Analysis in Multimedia Environmental Systems (FRAMES). FRAMES provides the infrastructure to seamlessly link disparate models and databases, providing an assessor with the ability to construct an appropriate conceptual site model from a host of modeling choices, so a myriad number

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of QMRA analyses can be supported and reproduced. The Microbial Risk Assessment Interface Tool (MRA-IT) is an open-source, integrated software environment for performing an application of the pathogen exposure, intake, dose, and risk, containing several key components, including, but not limited to, pathogen specification, exposure scenario identification, and dose-response relationships. The current version of MRA-IT lacks upstream fate and transport components that produce pathogen and indicator concentrations in the water column prior to exposure. The MRA-IT is seamlessly linked, using FRAMES, with upstream fate and transport models. The final package is a software technology framework that focuses on linkages across the source-to-outcome continuum and provides an illustrative demonstration of microbial fate and transport, exposure routes and scenarios, intake volumes, dose, and risk computations.

2009-A-275-ISES

Probabilistic Infectious Risk Assessment Model With Continued Exposure

Y. Huang, L. Hsiao; National Kaohsiung First Univ. of Science & Technology, Kaohsiung, Taiwan

The development of chemical risk assessment method helps estimates potential risks of adverse health outcomes and set environmental cleanup and containment goals. The risk assessment method for microbial infection takes similar process as chemical risk assessment. Infection can occur with single exposure to pathogens, and with a proper dose-response relationship, the risk of infection can be estimated under a given exposure scenario. Nonetheless, a quantitative assessment of microbial exposure is still difficult if not impossible. In many cases, microbial exposure may be continual and variable over time, and the risk of infection over time may be difficult to quantify. In this study, we propose a model that estimates risks of infection over time from exposure with pathogen. A negative binomial model was modified to estimate risk of infection over time. The model assumed that all of the susceptible subpopulation will eventually be infected under continued exposure, thus making the cumulative infection risk up to 1 at the end, upon which the outbreak stops. Epidemiological data of shigellosis outbreaks were used to estimate the risk of infection over time. The disease outbreak was assumed to end because all that were susceptible within the exposed group were infected. In all, 18 studies with clearly defined exposed and disease cases, the risk of infection for a susceptible person with one-time exposure was about 10-1. Twenty three studies with chronological records of shigellosis cases were fitted to estimate daily infection risk over time during the outbreak. The daily infection risk increased exponentially over time. By assuming that the outbreak ultimately stops with the last disease case, the risk of infection could be described with an exponential equation. The model parameter values differed among studies, which is likely due to different modes of disease transmission among cases.

2009-A-354-ISES

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Comparison Of Allergen Collection Efficiency For Two High-volume Carpet Samplers

M. Wang, J. Hwang, J. Adgate; School of Public Health, University of Minnesota, Minneapolis, MN

Background: The High Volume Small Surface Samplers HVS3 and the smaller, lighter HVS4 are vacuums for collection of allergens and pollutants in settled dust. Objective: To compare sampler performance under controlled conditions to see if they are equivalent. Methods: Carpet squares were doped with dust for known particle size fractions (bulk, 212-90, 90-45, and <45 microns) using the ASTM dust embedding method and were sampled using both samplers. Dust mass and allergen concentrations of dust mites (total Der p1 and Der f1), cat (Fel d1) and cockroach allergens (Bla g1) were quantified using ELISAs. Samplers were compared by exploring mass collection efficiency (CE= Fiber Corrected Dust Mass/ Applied Dust Mass), concentration ratio (CR =Allergen concentration in sample/Allergen concentration in test dust) and allergen collection efficiency (ACE =CE*CR). Results: Test dust allergen concentrations varied, especially for cockroach allergen. The CE of HVS3 was higher than but not statistically significantly different from HVS4 across the dust size fractions, indicating that the HVS3 picked up more dust mass. The variability in CR and ACE was greater than which in CE for the two samplers within the same size fraction. The CR and ACE of HVS3 was similar to the HVS4 for all allergens within the same size fraction, except the HVS4 recovered less cockroach allergen (Bla g1) compared to HVS4 (ACE, P=0.0012; CR, P=0.0044). However, this observed differences appear to be related to a higher variability in CR and ACE results. Conclusions: For dust mass the performance of the HVS3 and HVS4 were similar across the various particle size fractions tested. For allergen concentrations, the performance of the two samplers were also similar across the various particle size fractions. Overall, we would recommend use of HVS4 in the field for allergen sampling because if its relative ease of use compared to the HVS3.

2009-A-369-ISES

Data Collection On Industrial Use Of PFOS To Estimate Emissions

Y. Bruinen de Bruin, P. Zweers, J. Bakker, M. Beekman; RIVM - National Institute of Public Health and the Environment, Bilthoven, Netherlands

By order of the Dutch Ministry of Spatial Planning, Housing and the Environment (VROM), the RIVM compiled an inventory of Perfluorooctane Sulfonate (PFOS) used in two specific applications. These are its use as a mist suppressant/wetting agent in industrial chromium plating and as an agent in fire fighting foam. The primary aim of the inventory, with respect to the latter application, was to estimate existing stocks in The Netherlands.

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Assessment of total stocks was done by using sales data and extrapolation based on market shares. Substantial effort was put into the data collection and many contacts were made with industry. The obtained information on sales volumes and use served as a basis to estimate emissions and stocks on national scale. Assumptions were made on the distribution of annual sales volumes, release and use. In addition, sales volumes were extrapolated to represent nation wide market quantities. In the Netherlands, it is estimated that the worst-case maximum PFOS use in the metal plating industry is 390 kg PFOS annually as a mist suppressant/wetting agent. Highest stored volumes of PFOS containing fire fighting foam were found to be still present at airports and chemical-industrial locations, being about 3300 m3 and 3200 m3 respectively, on a total of 18540 m3. The data compiled in the inventory were provided by suppliers and are subject to uncertainty. More accurate estimations with known uncertainty can only be made on the basis of more data. The European Commission requested all Member States to compile an inventory of PFOS focusing on similar specific applications. The use of PFOS is restricted due to the risks it presents to both human and environmental health. The methodologies used for data collection and analysis can be applied for other purposes, such as REACH (Registration, Evaluation, Authorisation and Restriction of Chemicals).

2009-A-385-ISES

Characterization Of Residential Pest Control Products In New York City

M. K. Williams,1 D. Holmes,1 P. Shephard,2 C. Espino,1 A. Rundle,1 J. B. Jacobson,3 R. M. Whyatt1; 1Columbia University, New York, NY, 2West Harlem Environmental Action, New York, NY, 3Department of Health and Human Hygiene, New York, NY

Background. The Columbia Center for Children’s Environmental Health (CCCEH) reported widespread residential insecticide use in New York City. Product use has changed due to U.S. EPA restrictions on organophosphates. Research suggests pyrethroids are replacing organophosphates, however a systematic assessment of active ingredients used for residential pest control is lacking. Objectives. We documented the insecticides currently used by professional applicators and available in stores in the CCCEH catchment area in upper New York City. Methods. We queried a database of pesticide applications reported by professional applicators between 1999-2005. Data was collected for the 29 zip codes within the CCCEH catchment area. We also surveyed products available for pest control in 145 stores located within the CCCEH catchment area. Results. Between 1999-2005, professional applicators applied an aggregated sum of 51,866 gallons and 192,230 pounds of pesticides. The overall quantity of pesticides applied remained consistent between years. Active ingredients contained within insecticide formulations changed over time. Use of formulations containing organophosphate insecticides decreased significantly. Use of formulations containing boric acid increased significantly. Use of formulations containing pyrethroids remained constant. Within 145 stores surveyed in the CCCEH catchment area, 120 (82.5%) carried

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at least one insecticide. Spray can were found most commonly (114/120 stores, 95%), gels were least common (31/120 stores, 25.8%). Among spray formulations, pyrethroid insecticides were the most common class of pesticides recorded and permethrin, a pyrethroid, was the most common individual active ingredient. Only one store carried a product containing chlorpyrifos. One store carried a product containing diazinon. Conclusions. This survey suggests pyrethroid insecticides and some non-spray insecticides including boric acid have replaced organophosphates for pest control in this area. Chlorpyrifos and diazinon have nearly been eliminated from products marketed for residential pest control, illustrating the efficacy of the U.S. EPA phase out of these insecticides for residential pest control.

2009-A-411-ISES

Usage Patterns Of Personal Care Products In California Households

X. Wu,1 D. H. Bennett,1 D. Cassady,1 K. Lee,2 B. Ritz,3 I. Hertz-Picciotto1; 1UC Davis, Davis, CA, 2Seoul National University, Seoul, Republic of Korea, 3UCLA, Los Angeles, CA

There is concern over exposure to potentially toxic ingredients in personal care products (PCPs). Usage patterns of 30 types of personal care products (e.g. antibacterial soaps, hair products, fragrances, baby care products) in 631 California households were collected by telephone interview in each of two years. Frequency distributions for the various product types will be presented for the three participant groups surveyed, children under 9 years, parents of young children, and seniors. There were statistically significant differences in usage frequency (i.e. times per week) between parents and seniors for 65% of the types of PCPs surveyed. PCP usage frequencies were very low for children. Longitudinal variation of PCP usage frequency was also examined, with 60-100% of the adult participants reporting the same or nearly the same usage frequency for most PCPs at two annual interviews, resulting in moderate to strong correlation (0.46-0.89) between years for most product types. There was more longitudinal variation for children’s usage frequencies. We also determined the correlation between usage frequency and purchase frequency. Product preference was also investigated by age group. To determine if people accurately report use of natural body and bath products we asked both if they used a natural product (17-23%) and compare these responses to the reported brand. A number of the households reported using unscented body and bath products (15-50%), particularly for children (20-55%). Regarding brand loyalty, a majority of the population used the same brand for 2 to 3 years (38-58%) or 4 to 10 years (20-36%), while 7-12% of people buy a new brand each time. This study provides usage patterns of a large collection of commonly used PCPs in a large population. Results suggest consistent usage over time, allowing for evaluation at a single point in time in exposure assessment studies for studies covering several years.

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2009-A-592-ISES

Study Of Use Of Products And Exposure-Related Behaviors (SUPERB): Study Design, Methods, And Preliminary Results

I. Hertz-Picciotto,1 D. Cassady,1 K. Lee,2 D. H. Bennett,1 R. Vogt1; 1Department of Public Health Sciences, University of California, Davis, Davis, CA, 2Graduate School of Public Health and Institute of Health and Environment, Seoul National University, Seoul, Republic of Korea

Exposure to toxic chemicals in the home environment is an area of growing concern in the population though little research has been conducted to understand optimal home-exposure assessment methods over the life course. This study examines longitudinal exposure to food-based, product-based, and environmental toxins in the home environment via three platforms including telephone interview, web-based survey, and passive home-based monitoring. The purpose of this study is to generate longitudinal population-based exposure datasets characterizing short-term, seasonal, and long-term changes in exposure-related behavior. This paper presents the sampling and recruitment strategies of the targeted study populations, an overview of the three data collection platforms, and explanations of the instruments used to obtain information on each of the behavioral domains: food consumption, temporal-spatial activity patterns, and household product use. Results include response rates, study population demographics, and advantages to the new platforms relative to standard surveys. Two recruitment strategies were used for the two population groups sampled: birth records were used to recruit families (one parent and one child) from northern California and parcel mailings were used to recruit older individuals (age 55+) from southern California. Of 1,955 families successfully contacted, 480 (24.6%) enrolled. Of 2,658 individuals contacted, 152 (5.7%) enrolled in the study. This study will provide results on the accuracy, precision, completion rates, cost, feasibility, and user acceptability of three different platforms to collect longitudinal data on food consumption, temporal-spatial activity, and household product use. Further reports will provide critical information on seasonal and longitudinal patterns of exposure related behaviors in young children, parents of young children, and older adults. In addition, we will evaluate the platforms used here as potential approaches to be implemented in studies such the National Children’s Study, or other longitudinal investigations concerned with environmental chemical exposure, and ways to maximize compliance and study retention.

2009-A-453-ISES

Distribution Of Beverages Consumed Among Participants In The Binational Arsenic Exposure Survey

O. Contreras, J. Roberge, M. K. O’Rourke, R. Harris; University of Arizona, Tucson, AZ

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Introduction: From 1977 to 2001, energy intake from soft drinks and fruit drinks increased by 135%. The 2005 Dietary Guidelines for Americans concluded that from 1999-2004, 63% of adults drank sugar-sweetened beverages, averaging 28 ounces a day across all ethnic groups. This study investigated the distribution of beverages consumed among participants in the Binational Arsenic Exposure Survey (BAsES). Methods: This analysis utilized over 400 participants from Arizona and Mexico. All participants were over the age of 18. A 24-hour diet recall was administered during the household interview. Interviewers at all study sites were trained by the Arizona Diet and Behavioral Assessment Center at the Arizona Cancer Center. Results: Mexican participants consumed 0.93 L/day (sd ± 0.68) total fluids versus 2.8 ( ± 1.90) for Arizona Hispanics and 3.3 ( ± 2.60) for Non-Hispanics. Mexicans consumed 35.2% of all fluids from water and 30.6% from soda pops, while Arizona Hispanics consumed 53.1% from water and 13.8% from soda pops. The results were similar for Non-Hispanics in Arizona. There was a statistically significant difference between the water intake of Arizona participants and Mexican participants (p<0.001). The same was seen for soda pop intake (p<0.001). Discussion: Unlike participants from Arizona, Mexican participants are consuming a substantial portion of their total fluid intake from soda pops. The distribution of beverage intake of this population is important when evaluating contaminants such as arsenic which are predominantly found in fluids such as water. In BAsES, arsenic was found in higher concentrations in the urine of Mexican participants even though the arsenic concentrations in the drinking water were similar in Arizona. If the primary exposure to arsenic is from fluid intake, then further evaluation is needed to assess the arsenic concentrations in beverages such as soda pops in Mexico.

2009-A-412-ISES

Novel Methods For Assessing Consumer Product Use Through Bar Code Technology

D. H. Bennett,1 C. Teague,1 X. Wu,1 D. Cassady,1 K. Lee,2 B. Ritz,3 I. Hertz-Picciotto1; 1UC Davis, Davis, CA, 2Seoul National University, Seoul, Republic of Korea, 3UCLA, Los Angeles, CA

A novel platform was developed that used the bar codes readily found on consumer products to quickly and reliably determine what products people used in their homes, such that exposures to compounds found in these products can be determined. In addition, we determined the change in mass of the product over a one week period to assess the potential magnitude of exposure. The method was evaluated in a field study that included thirty California households with young children and seventeen households with an older adult. At the beginning of the week, we scanned a suite of cleaning, personal care, and pesticide products with a bar code scanner, weighed each container, and marked the container so that we could confirm, at our return visit the following week, if the container was the one from the beginning of the week. We visited households for 4 weeks over 16 months, such that

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temporal variability could also be calculated. Feasibility was evaluated in two ways. First, we determined the percent of product bar codes with ample information from public databases to identify the product and the percent with readable bar codes. For cleaning products, 43% of products had ample data, with another 44% having readable barcodes. For personal care products numbers were slightly lower, 47% and 16% respectively. Second, we determined that the majority of the time, the product was found again at the end of the week so mass use over the week could be determined. We then present the actual results, the distribution of mass used by product type and a comparison between inter- and intra-person variability. In summary, with some suggested changes to our protocol, this method appears to be very appropriate for gathering information related to potential exposures from cleaning and personal care products.

2009-A-472-ISES

Organophosphorus Pesticide Oxygen Analogs In Air Samples During And Following Agricultural Spraying: Are They Present In Air Or An Artifact Of Sampling?

J. L. Armstrong, R. Fenske, M. G. Yost, M. Tchong, J. Yu, K. Galvin; University of Washington, Seattle, WA

Title: Organophosphorus pesticide oxygen analogs in air samples during and following agricultural spraying: are they present in air or an artifact of sampling? Authors: Jenna Armstrong, Richard Fenske, Michael Yost, Kit Galvin, Maria Tchong, Jianbo Yu Agricultural applications can pose health risks to nearby communities through off-target movement of pesticides. The more toxic oxygen analogs of the organophosphorus pesticides have been detected in air and on surfaces following applications in several studies in California. An extensive air monitoring program was conducted in the agricultural regions of Washington State in 2008, and substantial levels of chlorpyrifos-oxon were measured in samples. This sub-study examined the extent to which the measured oxygen analog of chlorpyrifos was a true measure of the presence of the compound in the air or an artifact of sampling. OVS air sampling tubes were spiked with chlorpyrifos and air was drawn through the tubes at two flow rates for 24 hours at a Yakima Valley field site distant from pesticide spraying. Samples were analyzed for chlorpyrifos and its oxon using LC-MS-MS. These studies found that the oxygen analog could be produced by the air sampling process, with an inverse relationship between percent oxon produced and spiking level. For example, at a two liter per minute flow rate the oxon fraction averaged 25% +/- 8% at the lowest spike level (15 ng), but was 12% +/- 3% at the highest level (200 ng). However, numerous samples with relatively low chlorpyrifos levels (10-40 ng) collected during the air monitoring program had oxon fractions exceeding 50%. These results suggest that some amount of the oxygen analog in these samples was not an artifact, but was present in the air following pesticide

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applications. Additional studies will be needed to fully characterize the toxic properties of organophosphorus pesticide air contaminants in these agricultural regions.

2009-A-485-ISES

Conversions Of Chlorpyrifos And Cis- And Trans-permethrin In Duplicate Diet Foods To Metabolites As A Function Of Storage Conditions

M. G. Nishioka,1 M. McCauley,1 K. Andrews,1 N. Tulve2; 1Battelle Memorial Institute, Columbus, OH, 2US EPA, Research Triangle Park, NC

There is significant concern that pesticides in environmental matrices may undergo degradation during storage, thus affecting the accuracy of exposure assessments carried out on samples analyzed long after collection. This study measured the conversion of chlorpyrifos to TCPy and the conversion of a mixture of cis- and trans-permethrin isomers to metabolites 3PBA, cis-DCCA, and trans-DCCA. The evaluation was carried out using a representative mixture of duplicate diet solid food, a liquid food mixture, and infant formula. In the more comprehensive assessment performed for chlorpyrifos, aliquots of these foods were stored at room temperature and analyzed 3 times during an 8 hr period; aliquots of the foods were also stored in the refrigerator and analyzed 6 times over a 14 day period; similarly, aliquots stored in the freezer were analyzed 5 times over a 60 day period. A shorter protocol was used for the assessment of permethrin stability. Foods aliquots were spiked at the level of 50 ng/g prior to storage so that as little as 1% conversion would be detectable over the native levels of the metabolites. Results indicated that there is a small, but measureable, conversion of the parent pesticides to their corresponding metabolites, and the conversion varies by food matrix, temperature, and storage duration. For example, maximum molar conversion of chlorpyrifos in solid food stored in the freezer was 2.4% after 7 days, was 2.0% after 1 day for milk/juice stored in the freezer, and 5.9% after 60 days for infant formula stored in the freezer. Full results will be discussed. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy

2009-A-495-ISES

Particle Size Distributions, Size Concentration Relationships And Adherence To Hands Of Selected Geologic Media Derived From Mining, Smelting And Quarrying Activities

C. Bergstrom, J. Shirai, J. Kissel; Univ of Washington, Seattle, WA

Hand-to-mouth activity by young children is recognized as a potential pathway of exposure to soil contaminants. Observed soil and contaminant loads on hands are relevant to evaluation of this pathway. Soil adherence values based on common soils may or may

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not be appropriate estimators of hand loads of soil-like materials that contain large fractions of mining or smelting wastes or quarry product. The latter may also contain relatively high concentrations of elements of concern such as lead and arsenic. To aid evaluation of some specific regional areas of concern, geologic media were collected from bank deposits from three rivers impacted by mining and smelting, a roadbed built of smelter slag, and a quarry in which the rock contains naturally occurring arsenic. All media were sieved to provide particle size distributions. Whole media samples were evaluated for hand adherence using a dynamic handling procedure. Adherence tests employed six volunteers for each type of media under both wet and dry conditions. Median adherences of 7.1 and 0.66 mg/cm2 were observed across all media tested under wet and dry conditions respectively. Sieve-separated fractions and handwash samples were analyzed by ICP-MS for Pb, As, Cd, Co, Cr, and Zn. Maximum Pb concentrations of 32,000 and 9,550 mg/kg were observed in a sieve-separated fraction and handwash residue sample, respectively. Distributions of particle fractions adhering to skin were estimated by maximum likelihood estimation. Funding for this activity was provided by the Washington Department of Ecology (Interagency agreements C0700194 and C0900158) and by Iron Mountain Quarry, Inc. No endorsement by either funding source of the findings presented should be inferred. CM Bergstrom also received support via NIOSH 1T42OH0084301.

2009-A-379-ISES

Comparison Of Wipe Materials And Wetting Agents For Pesticide Residue Collection, Part 1: Study Design And Data Analysis

N. C. Deziel,1 S. M. Viet,1 D. A. Marker,1 J. W. Rogers,1 M. Dellarco2; 1Westat, Rockville, MD, 2NICHD, NCS, Bethesda, MD

There is no standard surface wipe for environmental sampling of pesticide residues in homes. While a variety of wipe materials and wetting agents have been used, materials differ in durability and ability to transfer pesticides and may contain binders and other substances that potentially interfere with chemical analysis. Properties of wetting agents may affect their ability to dissolve pesticides, influence stability of collected compounds, or cause damage to residential surfaces. A study was designed to compare the collection efficiency and coefficients of variation of pesticide residues obtained by wiping a hard surface with three different combinations of wipe materials and wetting agents considered for use in the National Children’s Study: Ghost Wipes, pre-packaged 6” x 6“ polyvinyl alcohol wipes wetted with deionized water; Twillwipes, 4” x 4”, wetted with 2.0 mL deionized water; and Twillwipes, 4” x 4”, wetted with 2.0 mL isopropanol. Thirteen replicates for each type of wipe and wetting agent combination were used, at both high and low concentrations. This total of 78 wipes was sufficient to provide 80% power to detect differences of 33% in collection efficiencies and differences of 50% in CVs. Each wipe was analyzed for 24 pesticides, with the average collection efficiency across these pesticides used in the statistical analyses. All analyses were conducted on a

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log scale. Differences in CVs between wipes were determined with an F-test, while differences in collection efficiencies were determined by analysis of variance. The Twillwipe wetted with isopropanol had significantly higher collection efficiency than the water-wetted Ghost Wipe, which in turn was better than water-wetted Twillwipe. CVs were comparable across wipes, but may be smaller using Twillwipe with isopropanol. While isopropanol appears to increase collection efficiency, this must be reconciled with other factors, such as the potential for surface damage.

2009-A-384-ISES

Comparison Of Wipe Materials And Wetting Agents For Pesticide Residue Collection - Part 2: Sampling And Laboratory Analysis

D. E. Camann,1 A. Y. Yau,1 M. H. Heikkinen,2 S. M. Viet,2 M. Dellarco3; 1Southwest Research Institute, San Antonio, TX, 2Westat, Rockville, MD, 3NICHD, NCS, Bethesda, MD

Surface wipe materials may contain binders and other agents that interfere with the analytical method. Wetting agents differ in their ability to dissolve pesticides and may influence the stability of collected compounds. A study was performed to compare the collection efficiencies of three combinations of wipe materials and wetting agents for pesticide residues applied on a stainless steel surface. Three wipe material and wetting agent combinations were evaluated: 1. Ghost Wipe, pre-packaged 6”x6” polyvinyl alcohol wipes wetted with deionized water (GW) 2. Twillwipe, 4"x4", wetted with 2.0mL deionized water (TW) 3. Twillwipe, 4"x4", wetted with 2.0mL isopropanol (TI) Acetone-cleaned stainless steel tool wrap was mounted on a plywood platform. Three templates (12”x12”) were placed side-by-side on the surface. A solution of 27 pesticides, primarily pyrethroids, organochlorines, and organophosphates, in ethyl acetate was applied to the surface inside each template, at either a low (8xDL) or high (80xDL) spiking level, as nine 10uL drops in a grid, and allowed to dry. GW, TW, and TI were used to wipe the three spiked surfaces. Field blanks and 13 replicate sets of low-level residue wipes were collected in systematically-varied order on one day. Field blanks, 13 replicate sets of high-level residue wipes, and high-level field matrix spikes were collected on another day. Samples were spiked with diazinon-d10, tetrachloro-m-xylene, and decachlorobiphenyl as extraction surrogates, Soxhlet-extracted with 250mL hexanes:acetone (1:1), and concentrated to 1.0mL. Individual pesticides and surrogates were determined by GC/MS selected ion monitoring employing six calibration standards covering a 50-fold range using 4,4’-dibromobiphenyl as the internal standard. Extraction surrogate recoveries spanned 65-110%. The three wipes were durable, easy to use, and none produced analytical interferences for the targeted pesticides in this laboratory setting. Given their variable performance, selection of the wipe material and solvent should take the compounds of interest into account.

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2009-A-421-ISES

Bake-out Is A Useful Method To Decrease Volatile Organic Compound (VOCs) In Prefabricated Room To Prevent Sick Building Syndrome

M. Hanazato,1 E. Todaka,2 H. Nakaoka,2 H. Seto,3 C. Mori4; 1Center for Health, Environment and Field Sciences, Chiba University / Department of Architecture, Graduate School of Engineering, Chiba University, Chiba, Japan, 2Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University / Center for Health, Environment and Field Sciences, Chiba University, Chiba, Japan, 3Tokyo Kenbikyo-in Foundation, Tokyo, Japan, 4Department of Bioenvironmental Medicine, Graduate School of Medicine, Chiba University / Center for Preventive Medical Science, Chiba University / Center for Health, Environment and Field Sciences, Chiba University, Chiba, Japan

Prefabricated room is used as temporal office at construction sites or temporal shelter room in case of mass disaster. However, it is reported that there are some people who show adverse health effects because the volatile chemical compounds (VOCs) indoor air from the paint on the surface of the ceiling, wall and floor are quite high. In Chemiless Town, in which houses and buildings are constructed with fewer chemicals, three prefabricated rooms are set up for the purpose of researching the VOCs from interior materials, and the total VOCs (TVOC) was analyzed. It became clear that the TVOCs of the rental prefabricated rooms are extremely different. The TVOCs of room A, B, C were 345μg/m3, 159μg/m3 and 60μg/m3, respectively. To decrease the TVOCs, bake-out method was taken. One term of bake-out was to keep the room temperature around at 40 degrees Celsius for 2 hours, then the doors and windows are open for 30 minutes for exchange the air. Twenty-two terms of the bake-out were practiced for 8 days. As the results, the TVOCs of room A, B, C was lowered to 44μg/m3, 34μg/m3 and 11μg/m3, respectively. It became clear that it is very useful to decrease the TVOCs in prefabricated room by bake-out method. In case of big earthquake or some natural disasters, prefabricated rooms are used for a few months to a few years. At construction site, people tend to think that if it is a short period, it doesn’t matter to be in high TVOC rooms. The sick building syndrome is easily forgotten, however, it is very important to maintain the room environment healthier for public health during the recovery period after disaster, and for labor environment.

2009-A-352-ISES

Brominated Diphenyl Ether Transfer From Plastic Pallets To Package Wrap

D. E. Camann,1 M. M. Zuniga,1 D. Deal2; 1Southwest Research Institute, San Antonio, TX, 2CHEP, Orlando, FL

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High-density polyethylene plastic pallets manufactured with 7% deca-brominated flame retardant are becoming widely used for freight transport of goods. Projected usage is 45,000,000 kg of deca-bromine in plastic pallets in the next four years. Experiments were performed to investigate the migration of brominated diphenyl ether (BDE) congeners from the plastic pallet onto the shrink-wrap of transported packages during shipment. Amounts and removal loadings of BDE congeners were measured in swab wipe samples of three plastic pallets, one wood pallet, and the shrink-wrap under product packages in direct contact with plastic pallets. Wipe samples were collected with two hexane-wetted SOF-WICK gauze pads, using lengthwise parallel passes in perpendicular directions with the two pads. Wipe samples were Soxhlet-extracted with 6% diethyl ether/hexanes or toluene. BDE congener amounts were determined by GC/MS/SIM analysis using 13C6-labelled BDE-153 as the internal standard for quantitation. No detectable BDE congeners were removed by the wood pallet swab. 4,020 to 7,500 ug/m2 of BDE-209 was removed in surface swabs of four plastic pallets, while 2,860 to 5,400 ug/m2 of BDE-209 was removed in swabs of the shrink wrap underneath product packages in direct contact with a plastic pallet during shipment. BDE congeners were undetected in unused shrink-wrap (< 0.2 ug/g) and removal loadings of BDE-209 were low (5 ug/m2) or undetected (< 2 ug/m2). Transfer proportions of BDE-209 from the top surface of the plastic pallet to directly-contacted shrink-wrap beneath three product packages were 0.670, 0.719, and 0.724. Similarly, transfer proportions of BDE-183 were 0.239, 0.272, and 0.169. These results demonstrate major transfer of BDE-209 (70% of surface loading), and substantial transfer of BDE-183 (mean 23%), from the plastic pallet to shrink-wrap beneath product packages. Contamination of packaging during transport on plastic pallets treated with deca-brominated flame retardant represents another route for human contact and exposure to BDE-209.

2009-A-603-ISES

Predicting The Relative Oral Bioavailability Of Arsenic From Soil: In Vitro Method Development

Y. W. Lowney,1 S. Griffin,2 J. Drexler,3 W. Brattin,4 P. Hunter,4 G. Diamond5; 1Exponent, Boulder, CO, 2U.S. EPA Region 8, Denver, CO, 3University of Colorado, Boulder, CO, 4Syracuse Research Corporation, Denver, CO, 5Syracuse Research Corporation, Syracuse, NY

A broad database has established that the bioavailability of arsenic from soil can be significantly less than the assumed default of 100%, and that the controls on bioavailability from soil vary with site-specific factors. Regulatory guidance allows for adjustment to account for such reduced bioavailability, with appropriate supporting data. To date, for arsenic, acceptance of such adjustments has generally required conduct of in vivo (i.e., animal) studies using site-specific soil/sediment samples. Although in vitro methods have been developed to predict the relative oral bioavailability of arsenic from soil, none has yet been fully validated against data from animal studies for a broad diversity of soil types or contaminant sources. This presentation will provide an update

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on current research to validate an in vitro method using existing in vivo data on the relative oral bioavailability of arsenic in soil from 41 different arsenic-containing test materials from mining, smelting, pesticide, and chemical plant sites across the U.S. that have been tested previously for bioavailability in either cynomolgus monkeys or juvenile swine. A fully validated in vitro method will provide a mechanism for efficient and inexpensive evaluation of the relative bioavailability of arsenic in soil that could be used to evaluate and/or support alternatives to the default assumption of 100% absorption of arsenic from soils. This presentation will provide a brief update on the status of in vitro methods for predicting the bioavailability of arsenic, and describe the study plan and discuss interim project results.

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Poster

W-P001b: Wednesday: Occupational, Water, Pesticides - Theme: Case Studies

2009-A-295-ISES

Derivation Of Soil Cleanup Levels For 2,3,7,8-tetrachloro- Dibenzo-p-dioxin As Toxic Equivalence T E Q D/f In Soil Through Deterministic And Probabilistic Risk Assessment Of Exposure And Toxicity

R. A. Budinsky,1 C. R. Kirman,2 L. J. Yost,3 L. L. Aylward,4 J. M. Zabik,1 C. C. Rowlands,1 T. F. Long,2 T. Simon5; 1The Dow Chemical Company, Midland, MI, 2The Sapphire Group, Beechwood, OH, 3Exponent, Saint Paul, MN, 4Summit Toxicology, Arlington, VA, 5Ted Simon, LLC, Winston, GA

Aerial deposition from historic Dow Chemical operations in Midland, Michigan has resulted in residential toxic equivalent concentrations for polychlorinated dibenzo-p-dioxins and furans (PCDD/Fs) concentrations in soil generally less than EPA’s 1 ppb cleanup level as toxic equivalents (TEQD/F), but in some cases are greater than the 0.090 ppb default Michigan Department of Environmental Quality (MDEQ) direct contact criteria (DCC). DCC estimates were calculated using deterministic and probabilistic methods. As part of ongoing efforts to address soil TEQD/F, extensive site-specific data have been collected including in-vivo and in-vitro oral bioavailability studies. In the deterministic assessment, these data were applied here together with a combination of conservative default exposure assumptions, site-specific exposure assumptions for exposure frequency, and a soil ingestion rate based upon data reported by Stanek et al. (2001). In addition, derivation of representative toxicity factors for use in PCDD/F risk assessment has been the subject of extensive scientific and regulatory debate including in-depth comments provided by two U.S. Environmental Protection Agency (EPA) Science Advisory Boards (SAB) and the National Academy of Science on the proposed EPA Draft Dioxin Risk Assessment. This risk assessment also derived toxicity values seeking to address those issues. In the probabilistic assessment, probability density functions were defined for toxicity parameters as well as exposure parameters. With deterministic methods DCCs of 19 ppb were calculated based on a linear slope factor and 250 ppb based on a non-linear slope factor. Application of probabilistic methods resulted in a wide range of DCC values, with the 1 ppb cleanup value traditionally used by EPA falling below the first percentile of calculated distributions.

2009-A-359-ISES

Exposure Assessment Of Polychlorinated biphenyls In The Current Japanese People

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C. Mori, H. Fukata, E. Todaka; Chiba University, Chiba, Japan

Our previous studies revealed that human fetuses and their mothers were exposed to several persistent organic pollutants (POPs). PCBs can be the candidate for represent POPs contamination, because blood PCB level is associated with other major organochlorines . In this paper, we will introduce the current exposure level of total PCBs in 526 Japanese people from prenatal period to 80 years old. Adult blood PCB level increased according to aging. Adult males and females without pregnant experience showed similar association pattern between age and PCB levels. On the other hand, PCB levels of females who have been pregnant were lower than those of males and females without pregnant experience during lactation period and afterward. Fetal exposure level of total PCBs was estimated as 0.04 ± 0.02 ng/g-wet (average ± S.D.) from the level in the cord blood. However, in the case of the infants lactated for more than 3 months, average values of total PCBs are 0.58 ± 0.27 ng/g-wet under 2 years old. There was correlation between the length of the lactation period and blood PCB levels. We also found an association between exposure to PCBs or HCH in umbilical cord and the occurrence of atopic dermatitis in Japanese infant. Using the results of our studies, we proposed to establish the health examination system for women at reproductive age. If women go through health examination of chemicals and if life intervention or medication is taken to those who are highly contaminated, the risk to future babies on atopic dermatitis or other adverse health effects may be able to decrease. It will contribute to health promotion of future generations by preventing fetal and lactational exposure of POPs.

2009-A-274-ISES

Health Risks Of Personal Exposure To Heavy Metals In Drinking Water Based On Real Measurements Of Exposure Factors In Miyang, Henan Province, China

X. Duan,1 Z. Wang,1 N. Huang,2 J. Nie,1 J. Zhang1; 1Chinese Research Academy of Environmental Sciences, Beijing, China, 2Jiangsu Polytechnic University, Jiangsu, China

The purpose of this research is to study health risks of personal exposure to heavy metals in drinking water in Miyang county, Henan province, China based on real measurements of exposure factors. Miyang county is located in the junction of Yangtze river and Huai river basin. Drinking water of people living in this area is from underground water which may be polluted by heavy metals emitted from nearby manufactories. In this paper, drinking water samples from 20 different sites of this county were collected for measuring 14 heavy metals by ICP-MS. About 2500 subjects with different ages and sex were selected to measure exposure factors. Time-activity of drinking water by ingestion and dermal contact of each individual subject during the last three days were kept in dairy in detail by questionnaires. Intake of drinking water from direct and indirect consumption of water and time duration of dermal contact to water in each individual subject were kept in record based on real time measurements. Health risk assessment models of USPEA were used to predict health risks. The results showed that cancer risks of people

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exposure to Arsenic were 9.3E-08 to 1.2E-07 from ingestion and 1.1E-07 to 1.3E-07 from dermal contact. Non-cancer risks of people exposure to Lead, copper and other 12 heavy metals were 2.6 E-07 to 1.7E-06 by ingestion and 1.5E-08 to 5.6E-08 t by dermal contact. The health risks of people exposed to heavy metals in drinking water in drinking water is acceptable. Sensitivity analysis based on Monte-carlo simulation showed that exposure factors (body weight, ingestion rate of drinking water, dermal contact time, surface area) contributes more than 60% of the health risk assessment results. It’s very important to use the accurate/proper exposure factors during health risk assessment.

2009-A-361-ISES

Estimation Of Dietary Intake Of Toxic Substances In Japan

S. Nakai; Yokohama National University, Yokohama, Japan

It is important to evaluate exposure levels of toxic substances for risk assessment. The purpose of this research was to estimate cadmium exposure of Japanese due to food intake, which was considered the most important in the exposure, and applying data on cadmium concentrations of food items and on the amounts of their intake to estimation models prepared. The amounts of food intake were taken from a database of the National Nutrition Survey and pooled for six years from 1995 to 2000. Cadmium concentrations in food were taken from field surveys on cadmium contained in agricultural products and the like, which were carried out by Ministry of Agriculture, Forestry and Fisheries of Japan. The estimation of Cd intake distribution and factors involved in the estimation were examined by the Monte Carlo simulation using the Japanese version of Crystal Ball. Log-normal distributions were presumed as the theoretical distribution of intake level, body weight and cadmium concentrations. Cd intake distribution was estimated by several scenarios. In the scenarios other than Scenario 1, it was presumed that food products containing Cd in concentrations exceeding the maximum level shall not be distributed. Scenario 1 used no Cd maximum level for any food product. Dioxins and Cadmium intake distributions among expected high-exposure groups were also estimated, and a simultaneous exposure assessment for dioxins and cadmium was examined. When no maximum level was set, the mean, median, and 95 percentile of the estimated cadmium intake were 3.47, 2.93, and 7.33 (μg/kg body weight/week), respectively. There was no regional difference for dioxins but cadmium showing regional differences. Those of whom intake of both contaminants exceeded TDI/PTWI were found out from all groups.

2009-A-405-ISES

Potential Incidental Heavy Metal Ingestion While Using Art Pastels

R. M. Ascher, J. C. Rosen, N. Odegaard, P. I. Beamer; The University of Arizona, Tucson, AZ

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Though regulation is common among many art supplies, it is not uncommon for artists to obtain products that may have been manufactured prior to current regulations. A visual arts graduate studio at The University of Arizona was the subject of an exposure assessment for potential ingestion of lead, chromium, and cadmium present in pastels from 1954. Surface wipe samples were taken of baseboards, tabletop, coffee mug, and cell phone. Additionally, the pastels were analyzed by XRF to determine concentration of the metals in each pastel color. Metals quantified in the pastels include: cadmium (max = 12,216 μg/cm2), lead (max = 4114 μg/cm2 ), and chromium (max = 125 μg/cm2). Other metals that may have negative health impacts, like mercury and strontium, were present, but in much smaller quantities. Data from the XRF was then used to model acute and chronic ingestion dose with a modeling software program for consumer products, ConsExpo 4.1. Modeling resulted in projected ingestion doses as much as 54 times higher than the occupational exposure limit for cadmium and 3 times higher than the limit for lead. Acceptable levels for contamination of surface dust were exceeded for all three metals on baseboards and for lead and chromium on the tabletop. Based on potential health effects, discontinued use of the pastels is recommended.

2009-A-237-ISES

Preliminary Marine Fish Risk Assessment: A Case Of South African Coastal Waters

M. R. Matooane; Council for Scientific and Industrial Research, Durban, South Africa

Preliminary Marine Fish Risk Assessment: a case of South African coastal waters Matooane, M.1, Leaner, J.2, Somerset, V.3, Williams, W.3, Masekoameng, E.4, and Mason, R.5 1Council for Scientific and Industrial Research (CSIR), P.O. Box 17001, Congella, 4013, Durban, South Africa. Tel: +27 31 2422300, Fax: +27 31 2612509, Email: mmatooane@csir.co.za 2Department of Environmental Affairs and Development Planning, Private Bag 9086, Cape Town, 8000, South Africa. 3CSIR, P.O. Box 320, Stellenbosch, 7599, South Africa. 4CSIR, P.O. Box 395, Pretoria, 0001, South Africa. 5Department of Marine Sciences, University of Connecticut, 1080, Shennecossett Road, Avery Point, Groton, Connecticut, USA. The objective of this study was to determine the potential mercury health risk from consumption of locally caught fish from the South African coastline for subsistence fishermen. Samples of marine fish species were obtained from local fishermen at various locations along the South African coastline, in July, 2007 and July, 2008. Fish samples were analysed at the University of Connecticut, USA, using the DMA-80 Direct Mercury Analyser for total mercury (THg). Concentrations of THg which showed great variability among the different fish species ranged from 14.38 to 486.36 ng/g wet weight. Risk estimates for explored hypothetical receptors based on the South African consumption patterns for fisherman and US EPA reference dose (RfD) were elevated (HQ >1) for the

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worst and intermediate exposure scenarios. Based on the explored scenarios, consumption of marine fish contaminated with Hg is likely to result in adverse human health effects for South Africa coastal fishermen. Although these results are constrained by limited sampling and a lack of population specific exposure data, they suggest the need for further research to better understand health risk implications of consumption of marine fish with elevated Hg levels. Key words: Risk assessment, mercury, fish, South Africa.

2009-A-371-ISES

Exposure To Perfluorinated Compounds In Municipal Drinking Water Related To Aqueous Film Forming Foam (AFFF) Use At Fire Fighting Training Sites

J. Kelly, V. Yingling; Minnesota Department of Health, St. Paul, MN

Background Aqueous film forming foams (AFFF) containing perfluorinated chemicals (PFCs), have been used since the 1960’s to extinguish petroleum fires. PFCs, including perfluoro-octanoic acid (PFOA), perfluorooctane sulfonate (PFOS), and perfluorohexane sulfonate (PFHxS) have been detected in groundwater at large firefighting training locations (military bases, airports, fire training schools). These findings have raised concern about potential contamination of drinking water near other fire training sites. Methods The Minnesota Pollution Control Agency (MPCA) surveyed fire departments, major airports, refineries, and fire training academies on the types and volume of fire fighting foams used and the location and frequency of training. The MPCA and the Minnesota Department of Health (MDH) evaluated the survey results and developed a prioritized list of sites for further investigation. MDH focused on sites near municipal water supply wells. Fifteen cities were identified as being at risk based on: proximity of the wells to training areas, well capture zone and groundwater flow direction, vulnerability to contamination, depth and construction of the wells, volume of AFFF used, and frequency of training. Seventy-two city wells were sampled in March - April, 2009. Results PFCs were detected in wells in seven cities; none exceeded state drinking water limits. The highest concentrations were detected in Cottage Grove, Minnesota where the results are confounded by the presence of a larger, industrial waste-related PFC groundwater plume. In general, the concentrations of PFCs detected were below 0.1 parts per billion. Conclusions Fire fighting training sites where PFC-bearing AFFFs are repeatedly used may pose a risk to drinking water supplies. However, sampling to date in Minnesota indicates PFCs concentrations in community wells near smaller fire training sites are below levels of health concern.

2009-A-306-ISES

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Alkylphenols In Human Milk And Its Relation To Dietary Habits In Central Taiwan

G. W. Chen,1 W. H. Ding,2 H. Y. Ku,1 H. R. Chao,3 H. Y. Chen,1 S. L. Wang1; 1Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Miaoli, Taiwan, 2Department of Chemistry, National Central University, Taoyuan, Taiwan, 3Department of Environmental Science and Engineering, National Pingtung University of Science and Technology, Pingtung, Taiwan

Alkylphenols such as 4-nonylphenol (NP) and 4-octylphenol (OP) are widely used as surfactants and detergents in domestic and industrial products and are the environmental hormone commonly found in daily foodstuffs. The objective is to determine NP and OP in representative sample of human milk collected 2 weeks after the delivery and examined the related factors including mothers’ demographic factors and dietary habits. Alkylphenols concentration were analyzed by gas chromatography mass spectrometry (GC/MS) for 59 human milk samples. Dietary information was obtained by food frequency questionnaire from healthy women, aged 20-47 years, from December 2000 to November 2001 in central Taiwan. Women who consumed cooking oil over median amount of >7 servings per week had significantly higher OP concentration (0.98 ng/g) than those who consumed less (0.39 ng/g) (P<0.05). The total OP concentration in human milk was significantly associated with cooking oil (β=0.62) and fish oil capsules (β=0.39) consumption after adjustment for age and body mass index (BMI) (P<0.01). The NP concentration was also significantly associated with fish oil capsule (β=0.38) and processed fish product (β=0.59) consumption (P<0.01). A marginal correlation between freshwater fish consumption and the NP concentration was observed. Factor analysis identified four food patterns (4 factors) that accounted for 58% of the total variability within the sample. The third pattern (cooking oil and processed meat products) was strongly associated with OP concentration in human milk after adjustment for age and BMI (P<0.05). Human milk level of OP and NP in this study appeared to higher than that of from Japan. Cooking oil consumption was positively associated with octylphenol concentration in human milk from healthy women in central Taiwan. Such study might be helpful for good recommendation of food consumption in nursing mothers to prevent excess exposure to NP/OP. Keywords: Alkylphenols, Human milk, Factor analysis, Dietary habits

2009-A-433-ISES

Exposure Assessment Of Occupational Coffee Roasting Oil Fume

C. A. Feng; Tajen University, PingTung, Taiwan

In recent years, the Coffee roasting business is booming in Taiwan. Home roasting coffee shops have opened one by one which bring more workforces into the roasting industry. The character of coffee roasting oil fume is like that of cooking oil fume. We review the cooking’s health exposure assessment by Chinese woman, and we find the oil fume

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induced lung disease. It results from immediately roasting coffee in coffee shop by coffee worker because consumers claim fresh coffee. The coffee worker exposures to oil fume by coffee roasting. We study the indoor air quality of coffee shops and use questionnaire to survey coffee worker’s risk. In this study, we choose home roast coffee shop in order to understand the changes of the indoor air quality in the coffee shop by the area measurement. The coffee shop is divided seven areas-outdoor area,roast areas,packaging areas,espresso areas,perceivable area of coffee bean and two seat areas on the 2nd floor. The measurement period is eight hours inclusive of 24 hours of continuous monitoring, and collecting sample of total dust. Total examination parameters are respectively formaldehyde,CO2,CO,VOCs,particle sizes,TSP,temperatures,relative humidity. Comparing numerical analysis of Taiwan indoor air quality with the standard of WHO indoor air quality, we find that formaldehyde,CO2,CO,VOCs,temperatures data are higher than the standard. According to questionnaire survey, the coffee worker gives a description of respiratory allergies and musculoskeletal disorders, such as skill, pate, shoulder and low back pain. The result comes that roasting is the main source of the polluted indoor air. We suggest the electrostatic precipitator be set up and maintained because ventilation reduces chemical pollutant and decreases the health risk in a suitable and restful environment.

2009-A-401-ISES

Methomyl And Carbamate Exposure From Jasmine’S Agriculture In Khon Kaen Province, Northeast Thailand

L. Charerntanyarak,1 P. Chuaybamroong,2 K. Harnpicharnchai,1 P. Suggaravetsiri,1 N. Khaorat1; 1Khon Kaen University, Faculty of Public Health, Khon Kaen, Thailand, 2Thammasat University, Faculty of Science and Technology, Pathumthani, Thailand

Jasmine has been grown widely in Khon Kaen Province, northeast of Thailand. Methomyl and carbendazim are the most popular pesticides used in the field. Their concentrations in the air, soil, and water were investigated simultaneously in the field and at 25-m upwind and 50-m downwind. Air samples were collected by a high volume air sampler with quartz filter and sorbent tube. The amount of 1.5 liters for surface water sample and 1 kg for soil sample were collected at each point, respectively. The concentration of methomyl and carbendazim at breathing zone air samples of 24 jasmine workers and 24 people living near the field were collected by universal pump model 224-PCXR8, air flow rate 0.1-1.0 l/min with filter/solid sorbent tube (OVS-2 tube: 13- mm quartz fiber filter, XAD-2, 270 mg/140 mg). All samples were digested and analyzed by HPLC-UV Detector. The ambient concentrations of methomyl found 408, 782, and 916 μg/m3 at upwind, in the field, and downwind respectively, while those for carbendazim were 17.9, 4.8, and 10.6 μg/m3, respectively. Methomyl concentrations in soil were 0.04, 0.11, and 0.09 mg/kg-dry weight for upwind, in the field, and downwind, respectively, whereas carbendazim in soil was not found. For surface water, methomyl found 2.55, 1.96, and

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3.56 mg/L at upwind, in the field, and downwind, respectively. Again, carbendazim was not found in water. The average concentration of methomyl in breathing zone air of people living near the filed and jasmine workers were 0.59 ± 0.40 μg/m3 (nil-1.03 μg/m3), and 183.02 ± 311.77 μg/m3 (nil-1118.60 μg/m3), respectively. Carbendazim was not found in any population samples. The results did not exceed the standard regulatory; PEL from OSHA, TLV-TWA from ACGIH. However, the jasmine workers and the people living near the field should be aware of exposing to the methomyl and carbendazim for better protection.

2009-A-591-ISES

Risk Assessment For Dermal Exposure Of Organochlorine Pesticides For Local Fishermen In The Rangsit Agricultural Area, Central Thailand

W. Siriwong,1 K. Thirakhupt,1 M. Borjan,2 S. Keithmaleesatti,3 J. Burger,2 M. Robson2; 1Chulalongkorn University, Bangkok, Thailand, 2Rutgers University, New Brunswick, NJ, 3Khon Kaen University, Khon Kaen, Thailand

Organochlorine pesticides (OCPs) used in agriculture and for public health purposes were banned in Thailand over the past decade; however, their persistent residues have been found in several agricultural areas of the country. This may result in adverse effects to human populations. This study investigated the concentration of organochlorine pesticides residues (OCPRs) in surface water and evaluated the potential cancer risk associated with dermal contact of the local fisherman fishing in the Khlong 7 canal, Rangsit agricultural area, central Thailand. Water samples were extracted using liquid-liquid extraction (LLE) and then analyzed by gas chromatography with microelectron capture detector (μ -ECD). The results show that low concentrations of OCPRs were detected in parts per billion (ppb or ng/ml) levels, that is, ∑ Endosulfan ( -, β -, and -sulfate) 0.082 ng/ml > DDT and derivatives 0.019 ng/ml > ∑ HCH ( -, γ -, β -, and δ -HCH) 0.014 ng/ml > aldrin and dieldrin 0.007 ng/ml > heptachlor and heptachlor epoxide 0.0068 ng/ml > endrin and endrin aldehyde 0.005 ng/ml > methoxychlor 0.001 ng/ml, respectively. Using the worst-case scenario defined as the reasonable maximum exposure (RME) to assess the potential cancer risk, five OCPs (dieldrin, 4,4' -DDT, β -HCH, heptachlor, and heptachlor epoxide) may pose a risk of concern on a lifetime human carcinogenesis greater than one in a million. Keywords: organochlorine pesticides; human health risk assessment; dermal exposure

2009-A-270-ISES

Assessment Of The Health Effects Of Exposure To Pesticides On Tobacco Farm Workers In Nigeria

O. O. Onigbogi, O. Akinyemi; University College Hospital, Ibadan, Nigeria

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Objective: Pesticides are currently being used extensively on many Nigerian tobacco farms. This study was conducted to assess the reported effects of pesticide use on the health of workers in these places. Material and Methods: A cross-sectional survey was carried out using interviewer-administered questionnaires. It also had a qualitative component on reported general health condition of the respondents. Results: A total of 117 tobacco farm workers were surveyed. Mean age was 17.5 years (SD ± 2.5). Eighty two (76%) of the respondents were of the opinion that pesticides use had short and long-term health effects on those who are exposed to them. Ninety-four (86%) of them were aware of the need to have prior training on the use of the pesticides. However, only 21(18%) had ever taken a formal course in the use of these products. Ninety (82%) workers were aware of the need to use Personal Protective Equipments (PPE) but 35 (40%) used it always while 63 (69%) used it sometimes. The reasons given for the failure to use PPE include heat, easy fatigability during use and unavailability of PPE. The mean attendance at a clinic for consultation over the past 6 months was 4.5 (SD ± 0.65). The commonest symptoms at presentation were allergic eye symptoms (29%), cough (18%), backache (17%), nausea and vomiting (7%), and skin allergy (8%). Eighty respondents (74%) had taken some over-the-counter medication or local concoction about 24 hours before the survey. Twenty-seven (23%) respondents classified their general health condition as good whereas 90 (77%) of them thought that it was bad. Conclusions: The low level of awareness of the short and long-term health effects of the use of pesticides without PPE is of concern and should be investigated in the larger population of tobacco workers and agricultural workers in general.

2009-A-230-ISES

Effectiveness Of Neem Oil On Anopheles Gambiae And Periplaneta Americana As A Potential Bio-insecticide In Nigeria

A. A. Ayinde; University of Ibadan, Ibadan, Nigeria

Environmental health risks associated with the use of synthetic insecticide have dictated for alternatives with minimal toxicity. The study therefore was designed to extract and test the bioinsecticidal potential of Azadirachta oil on two insect of public health importance. The study was experimental in nature. The oil was extracted by organic solvent extraction technique using N-hexane from ground seed kernel. The insects used were Anopheles gambiae (larvae and adult) and Peripleneta americana (nymphs and adult), laboratory reared and randomized into test and control groups. Larvicidal tests were done by exposing 600 larvae to oil solution (100-500ppm) emulsified by surfatatant (Tween 80) in triplicates. Mortality was counted and recorded every 24 hours for 5 days. Repellency

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tests were carried out by exposing experimental animals previously treated (topically) with the solution of oil in paraffin (10-40%v/v) to adult female Anopheles in netted cages. Repellency was estimated by the number that did not bite in 60 second in triplicates at hourly interval for 4 hours. The oil in glycerol (40%v/v) was also assessed on Periplaneta americana for contact toxicity. Observation was made immediately and followed up for 5 days. Data were subjected to both descriptive and inferential statistics. The oil yield accounted for 40% weight (432ml/kg). The larvicidal effect was significant across the concentrations (91-95%) with 100% pupal inhibition (p<0.01). The oil gave 92-95% repellency across the concentrations and dwindled with time but variations were not statistically different. The oil gave 100% feeding deterrence, reduced the locomotive rate and caused 100% mortality in nymphs after 30minutes of exposure whereas 60% mortality in adult after 5 days for Periplanata americana. The study therefore demonstrated the capacity of Azadirachta indica oil as a potential insecticide against Anopheles gambiae and Periplaneta americana as alternative insecticide for community use. Field trial of this product is highly recommended.

2009-A-504-ISES

Identification Of Pesticide Residue Sources In Low-income African-american Households Using Positive Matrix Factorization

C. Hemphill,1 G. Adamkiewicz,1 Y. Lee,1 D. Camann,2 R. Gragg,3 J. Spengler1; 1Harvard University School of Public Health, Boston, MA, 2Southwest Research Institute, San Antonio, TX, 3Florida A&M University, Tallahassee, FL

Background and Objective Pesticides include a broad class of chemicals used for pest control in residential, commercial and agricultural settings. Independent studies have identified high levels of pesticide residue in homes of both low-income urban residents and rural farm workers. However, a detailed picture of overall pesticide burden and sources in these communities is widely unknown. Contributions to indoor pesticide exposure come from sources such as current use, agricultural drift and occupational exposures. The objective of this study is to evaluate levels and sources of pesticide residue within urban and rural segments of a population, using traditional methods and positive matrix factorization (PMF). PMF is a statistical method that reduces the complex relationship between correlated variables to a smaller set of variables, called factors. Methods Dust samples and pesticide use data were collected from 200 homes in two predominantly African-American and low-income communities: Roxbury, an urban community within Boston, MA and Gadsden County, a rural county in Florida. Samples were analyzed for a suite of pesticides including organochlorines, organophosphates, pyrethroids and pesticide synergists. Results Preliminary results show a higher number of pesticides in Gadsden County when compared to Roxbury. As expected there is significant correlation between pesticides in

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the same class and between pesticides and synergists. In addition, restricted use pesticides such as methoxychlor and DDT are correlated. Preliminary results of PMF analysis show that five factors may be sufficient to describe the variation in the data. One of these factors exhibits a strong signal for pyrethroids, which represent residential use. Discussion A handful of factors describe the sources of pesticide exposure, and the clarification of these sources will be completed through final analysis of the data. Understanding the factors will assist in the development of interventions that can effectively reduce pesticide exposure.

2009-A-297-ISES

Assessment Of Bacteria In Drinking Water In Rural Guatemala To Inform An Intervention Strategy

S. Lacey,1 R. Lopez,1 C. Frangos,2 A. Khodadoust1; 1University of Illinois at Chicago, Chicago, IL, 2Clark Dietz, Inc., Chicago, IL

Background: A community health assessment identified diarrheal disease, particularly among children, as a primary morbidity concern for a rural community in Guatemala. The current water system entails well water pumped to a main cistern and then gravity fed to individual households. Since community growth has exceeded system capacity, water is available to sectors of the community on a rotating basis, so drinking water is stored at households for 2 to 3 days between re-supply. Preliminary field testing detected coliform bacteria in drinking water and prompted an exposure assessment to identify the type and source of contamination. Methods: Water samples were taken from 28 households spatially distributed along the water supply system. At each household, one sample was taken directly from the supply tap and one sample from the drinking water storage container, for a total of 56 samples; two additional samples were taken at the main cistern. A test battery including aerobic bacteria, total coliform, fecal coliform, and Escherichia coli, was performed on all samples; salmonella testing was performed on a subset of samples. Results: Results for aerobic bacteria, total coliform, fecal coliform and E-coli ranged from above and below limits of detection for each agent. Nearly all samples taken directly from the household tap were near or below limits of detection. Salmonella was detected at only one household drinking water storage container. Conclusions: These data suggest the well water being supplied to the households is virtually free of contamination at the main cistern and through the distribution system. Bacteria contamination appears to be isolated to drinking water storage containers at the household level. These data will inform a temporary intervention strategy to reduce bacteria concentrations in drinking water until a sustainable engineering solution can be devised to eliminate the need for drinking water storage at the household level.

2009-A-291-ISES

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Pilot Methodology For Analysis Of Water, Sanitation And Hygiene Linkage To Health, Khon Kaen Province, Northeast Thailand

L. Charerntanyarak,1 T. Boonyakarnkul,2 J. Moontep,3 U. Inmuong,1 S. Bualeang4; 1Khon Kaen University, Faculty of Public Health, Khon Kaen, Thailand, 2Department of Health, Ministry of Public Health, Bangkok, Thailand, 3Khon Kaen Provincial Health Office, Khon Kaen, Thailand, 4Khon Kaen Municipality, Khon Kaen, Thailand

The study aimed to undertaken rapid assessments of water, sanitation and hygiene linkages to health situation by using the environmental burden of disease methodology in Khon Kaen province, Northeast Thailand. This study scoped only diarrhea that almost caused by water, sanitation and hygiene. All households in Thaeparak 3-4 communities (N = 201) were the urban area. The sample size (N = 253) was calculated for rural area in Nongkungyai sub-district, Kraneun district where was the highest incidence during 5 years in the province. Data collections were used by questionnaires and interviewing. Results indicated that 29 cases (14.4 %), 33 times and 27 cases (1.07%), 32 times of diarrhea occurred in urban and rural areas over the past 3 months, respectively. Almost in urban (88.1%) and rural (71.1%) areas had improved water supply and basic sanitation in a country that was not extensively covered by those services, and where water supply was not routinely controlled. Relations of the rates of diarrhea cases in rural and urban areas were associated between the groups of having drinking water with and without treatment before drinking (OR=2.60, 95% CI = 1.04-6.46, P-value = 0.02 and OR=2.74, 95% CI = 1.11-6.96, P-value = 0.02, respectively). DALYs was found 0.2857 and 0.2270 years in rural and urban areas, respectively. The findings revealed that the year of life lost (YLL) was zero. If the data was adjusted to the population of Khon Kaen province and country, DALYs were 78.4095 and 2,937.2785 years, respectively. Moreover, if it calculated in the disability by cost of illness, DALYs in rural and urban areas were 9,663.06 and 8,119.89 Baht, respectively. Attributable burden to water, sanitation and hygiene in urban and rural areas were 0.0597 and 0.0579 year, respectively. Attributable burden to water, sanitation and hygiene in both study areas was 0.1176 year.

2009-A-296-ISES

Exposure To Human Waste From Spills While Servicing Aircraft Lavatories: Hazards And Methods Of Prevention

S. Lacey, A. Abelmann, S. Dorevitch; University of Illinois at Chicago, Chicago, IL

Background: Workers service the lavatories of commercial aircraft approximately 11 million times per year in the United States. Individuals who service the lavatories may have exposure to the spectrum of pathogenic viruses, bacteria and parasites potentially found in human waste. Methods for preventing worker exposure have not previously been described. Methods: An industrial hygiene walk-through of the workplace at one international

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airport was conducted by an interdisciplinary occupational health and safety team. Lavatory waste operators and supervisors were interviewed and the process was observed. Results: Exposures can range from droplets of dermal contact to the ingestion and inhalation of large volumes of untreated waste. Engineering and administrative measures that would ensure the effective locking of a critical valve, and a mechanism for communicating valve locking problems, were advised. Conclusion: Lavatory spills can result in substantial exposure to a variety of pathogenic microbes. Several administrative and engineering measures are advised to minimize worker exposure.

2009-A-260-ISES

Determination Of Settled Dust Fungi In Paris Newborn Babies' Homes

C. Persoz,1 C. Dassonville,1 S. Barral,2 V. Bex-Capelle,2 I. Momas,1 N. Seta1; 1Université Paris Descartes, Laboratoire de Santé Publique et Environnement EA 4064, Paris, France, 2Laboratoire d'Hygiène de la Ville de Paris, Paris, France

Background. An ongoing Parisian birth cohort study aims at examining environmental/behavioral factors associated with respiratory and allergic disorder occurrence in early childhood. As part of this study, an environmental investigation in 196 newborn babies’ homes was carried out to assess airborne and dustborne biological contaminants levels and their determinants over the first year of babies’ life. Objective. The aim of this study was first to assess settled dust fungal flora and allergen levels in newborn babies’ homes and second to identify their determinants. Methods. Dust samples were collected twice a year on cellulose filter with a modified vacuum cleaner from the child’s bedroom floor of each household. A 0.02% Tween 80 suspension was plated onto MEA/chloramphenicol agar and malt yeast 40 % sucrose agar. Plates were incubated at 25°C during 5 days. Simultaneously, allergens levels (Alt a 1, Asp f 1) were measured with ELISA assays. Housing characteristics were assessed by an interviewer administered questionnaire. Results. Penicillium, Aspergillus and Cladosporium were found in respectively 72%, 56% and 15 % of dust samples. Geometric mean (GSD) of total fungi levels was 1.7 104 (7.5 103) UFC/g of dust. Using a logistic regression analysis, presence of Penicillium and Aspergillus was associated with home characteristics (oldness of building, carpeted floor in infants’ bedroom) and inhabitants’ behavior (presence of furry pets, cleaning frequency with wet mop). Cladosporium was associated with high outdoor temperature and longer aeration duration. No relation was observed between fungi levels in dust and indoor air. Fungal allergens could not be detected in any of the dust samples. Conclusion. This study provided for the first time house dust fungal spectrum in Paris and contributed to identify factors that determined their presence. In addition, the allergens levels assessed in dust samples do not seem to represent the real fungal allergenic exposure.

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2009-A-441-ISES

Biological Contaminants Assessment In Paris Child Day Care Centers

C. Roda,1 M. Tribout,1 C. Dassonville,1 S. Barral,2 M. Dusseaux,2 I. Momas1; 1Université Paris Descartes. Laboratoire Santé Publique et Environnement-EA 4064, PARIS, France, 2Mairie de Paris. Direction de l'Action Sociale de l'Enfance et de la Santé. Laboratoire d'Hygiène de la Ville de Paris, PARIS, France

Background. Children are susceptible to air pollution effects. Currently, there is a lack of data on air quality in child day care centers which welcome infants. Objective. The purpose of this study was to document biological contaminants (house dust mites, mould and endotoxins) levels in Parisian day nurseries. Methods. Child day care centers were selected from facilities frequented by a random sample of babies who participate in the Parisian birth cohort study. Air and dust samples were collected twice a year in the infant section of twenty eight day nurseries. Sequential duplicate air sample of fungi were collected with a single-stage multi-holed impactor with chloramphenicol/MEA agar inside and outside the building. Airborne endotoxins were sampled on a glass fiber filter in polystyrene filter holders, using a pump (flow rate = 1.0 L/min, 24 h) and analyzed by a chromogenic kinetic Limulus Amoebocyte Lysate test. House dust mite allergens levels were analyzed with an ELISA method in dust vacuumed from babies’ mattresses. Comfort parameters and carbon dioxide levels were measured simultaneously. A standardized questionnaire was administered to gather information about building characteristics, cleaning practices, number of children enrolled and staff. Results. Penicillium and Cladosporium were the genera most frequently found in indoor air (respectively 82% and 61% in cold season, 73% and 81% in warm season). Total outdoor and indoor fungi were higher in warm season than in cold season: 415 UFC/m3 versus 242 UFC/m3 and 346 UFC/m3 versus 121 UFC/m3 respectively. Geometric mean concentration of endotoxin levels was 1.76±1.70 EU/m3. As for house dust mite allergens, Der p 1 and Der f 1 levels were below 2 µg/g of dust in almost all facilities and were detected in 12% and 32% of samples respectively. Conclusion. This study provides for the first time biological contaminants levels in Parisian day nurseries.

2009-A-404-ISES

Estimates of Occupational Noise Exposures and their Impact on Hearing Impairment: The National Health and Nutrition Examination Survey 2001 to 2004

Y. Choi,1 H. Hu,1 B. Mukherjee,2 J. Mille,3 S. Park1; 1Department of Environmental Health Sciences, University of Michigan School of Public Health, Ann Arbor, MI, 2Department of Biostatistics, University of Michigan School of Public Health, Ann

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Arbor, MI, 3Department of Otolaryngology, University of Michigan School of Medicines, Ann Arbor, MI

Background: Hearing loss is one of the most common health disabilities in older adults, and long-term noise exposure is one well-known risk factor for hearing loss. While the association between occupational noise exposure and hearing loss is well established in high-noise exposed occupation groups, the association between occupational noise exposure and hearing loss has been little examined in the general population. The goal of this study was to adapt and apply an assessment method for evaluating occupational noise exposure to examine the impact of this exposure on hearing impairment in the U.S. general population. Materials and Methods: Occupational noise exposure was assessed by utilizing the O*NET (Occupational Information Network) database which had been collected through questionnaires across numerous occupations, asking the frequency of exposure to sounds and noise levels that are distracting and uncomfortable. The association between these estimated occupational noise exposure and hearing ability was then assessed in 1,982 adults (20-69 years of age) from the NHANES 2001-2004. Air-conduction hearing threshold (dB) at speech frequencies was computed as a pure-tone average (PTA) of 0.5, 1, 2 and 4 kHz. We fit linear regression models with quintiles of occupational noise exposure, adjusted for non-occupational sources noise exposures and potential confounding factors. Results and Discussion: The PTA of a worker in the highest quintile group was estimated to be 2.42 dB higher than that in the lowest quintile group (p-value = 0.022). We also observed a dose-dependent elevation of PTA across quintile of occupational noise (trend p-value = 0.022). This study suggests that application of the O*NET method of assigning exposure to occupational noise enables the detection of the expected association of occupational noise exposure with hearing loss in the general population. This creates a widely-available and applicable assessment tool for examining noise-induced health effects in the general population.

2009-A-249-ISES

The Current Situation Of Traffic Noise In Xi'an City And Its Effect On Distraction In Class Among Children

J. Liu, X. Pan; Peking University, Peking, China

Background and Objective The purpose of this study was to get knowledge of the current traffic noise level in Xi'an city and to examine exposure-effect relationships between traffic noise exposure and children's distraction in class. Methods:The overall current noise level is monitored, especially on noise from traffic.We set 126 monitoring sites in the whole city, and collect data for three months. We compare the noise level in different life zones, and try to find out which is the highest of all. We conducted a study assessing 1890 pupils, aged 8-10, from 42 schools near major traffic road or not, from all eight urban areas in Xi'an , children are selected on the basis of

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exposure to external road traffic noise exposure. A well administered questionnaire concerning distraction in class and demographic information was distributed to these pupils and their teachers. Results : The noise from major road take above 20% of the overall noise in Xi'an city, and has reached a average level of 62 dB, exceeding the concern level of effecting public health problems. Among all the life zones, ones that near the major traffic road have the highest noise level. Traffic noise exposure was significantly associated with an increased score on behavior of distraction among children after full adjustment. Conclusion :The assessment of noise level in Xi'an city suggested that noise level in urban area of Xi'an has reached an alarming level. Meanwhile, a population survey in children revealed that living near a road with heavy trafic volume is one of the risk factors for distraction in class among pupils, which has become an important problem of the school behavior and effective learning among children.

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Poster

W-P001c: Wednesday: Occupational, Water, Pesticides - Theme: Strategies for Exposure Assessments

2009-A-455-ISES

Applying Bayesian Statistics To Incorporate Qualitative Information Into A Quantitative Probabilistic Exposure Model

S. F. Arnold; University of Minnesota, Minneapolis, MN

In pursuing a comprehensive approach to exposure assessment, industrial hygienists must make efficient use of both qualitative and quantitative exposure and exposure determinant information. As the need to use more state-of-the-art tools such as mathematical models increases, so too does the need to collect and incorporate qualitative information into quantitative algorithms. For example, collecting workplace air dispersion data is rarely possible but acquiring semi-quantitative or qualitative information is. This information cannot currently be systematically incorporated into mathematical exposure models. Industrial hygienists, researchers and regulators alike need methodologies with which to format this qualitative information so that they can use the information in quantitative models. One approach could include applying Bayesian statistics to reformat relevant and high quality but atypically formatted scenario and parameter information so that it is compatible with these mathematical exposure models. These Bayesian methods provide an inherent transparency to the assessment of uncertainty and bias - allowing the user to better understand the strengths and limitations surrounding the use and treatment of this information. Using a case study, this poster will illustrate the application of Bayesian statistics to reformat appropriately collected, qualitative survey information into quantitative parameter values that are then applied to the exposure model. It will include consideration of this qualitative information to establish the Bayesian prior judgment and sources for updating the prior; the prior and likelihood estimates will then be used to generate the quantitative parameter values that can be used in a robust, quantitative probabilistic exposure model.

2009-A-60-ISES

Prediction Of Aggregate And Cumulative Exposures From Data On Exposures From Individual Sources

P. Price; The Dow Chemical Company, Midland, MI

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Concerns for aggregate and cumulative exposures are based on the observation that exposures to a chemical, or groups of chemicals, occur from multiple sources and therefore the total dose of a chemical, or chemicals, will always be higher than the dose from any single source. In this project the magnitudes of the differences between the doses from individual sources and aggregate or cumulative doses are investigated using data from aggregate exposure assessments and simulation models. The project systematically investigates the impact of the number of sources and measures of the inter individual and inter source variation in doses on the differences between the maximum source-specific doses and aggregate or cumulative doses in individuals in exposed populations. We find that aggregate and cumulative doses are significantly larger than the maximum source-specific doses only when individuals receive similar sized doses from multiple sources. The maximum dose may be similar in size to the doses from aggregate and cumulative studies when source-specific doses are highly variable. In addition, it was found that in any exposed population the larger the aggregate and cumulative dose received by an individual, the more likely the dose was dominated by an exposure from a single source. These findings suggest that for many chemicals (and groups of chemicals that act either act independently or show dose additive) independent assessments of doses on a source-by-source basis may be sufficient to address risks from aggregate and cumulative exposures.

2009-A-492-ISES

A Proposed Approach To Describing Multi-agent Exposures

V. Ilacqua; University of Florida, Gainesville, FL

The current, real or perceived, inability of environmental health research and policy to adequately take into account the risks of simultaneous exposure to multiple agents has several causes, including the complexity of the issues, the lack of information on joint mechanisms of toxicity, and on actual population exposures. Another more immediate and simpler obstacle, however, is the lack of a shared and accepted way to even represent exposure to multiple agents in an analytical and quantitative manner. The discussion of these exposures, and their potential effects, is then confined to expressions of imprecise meaning, subject to the vagaries of interpretation, so that many instances of multiple exposures actually observed in experimental studies remain buried in the text, below the attention of the readers. A possible approach is offered, along with a formal notation, to systematically express concurrent exposures to multiple agents, with the hope of stimulating discussion within the society that may eventually lead to a shared convention. Based on vector notation, it offers distinctive advantages in terms of precision, brevity, and interpretability, for reporting results, structuring exposure databases, and analyzing data. These advantages are even more valuable when dealing with population, rather than individual, exposures, which present an additional degree of complexity. Examples of applications will be presented, and the potential uses and benefits beyond exposure science, in toxicology and risk assessment will be discussed.

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2009-A-569-ISES

A Novel Method For Reducing The Number Of Potential Agents To Be Studied In An Occupational Epidemiological Study

J. S. Pierce, N. A. Esmen, S. E. Lacey, K. J. Kennedy, R. P. Hancock; University of Illinois at Chicago, School of Public Health, Chicago, IL

An all-cause mortality occupational epidemiological investigation is underway concerning a group of jet engine manufacturing workers in the United States. The cohort (n ≈ 220,000) includes individuals who worked in any of the company’s 8 primary facilities between 1952 and 2001. While it would be ideal to study the health outcomes of workers relative to cumulative exposure on an agent-by-agent basis, the time required to do so, and the quantity of chemicals used over time makes this endeavor infeasible. In order to achieve the required efficiency in the reconstruction of exposures, a new method is being developed that treats each part as an exposure and each process as an exposure. Cumulative exposures to parts and processes for each worker will be assigned on the basis of year and job title, and the relationship between exposure and mortality will be determined. Should an association be detected between any part and/or process and a health outcome, this qualitative analysis will yield a reduced “part and process” set which can then be investigated in detail and the agents involved considered further for quantitative reconstruction. This method is efficient, and has the potential to benefit future complex exposure-reconstruction studies, particularly when there is no predetermined exposure associated with an observed increase in a cause-specific mortality.

2009-A-273-ISES

Suggestions On Human Exposure Factors Of Chinese People In Health Risk Assessment

X. Duan, Z. Wang, J. Nie, J. Zhang; Chinese Research Academy of Environmental Sciences, Beijing, China

Human exposure factor is one of the important parameters in health risk assessment model. However, there are still huge data gap in exposure factors in China. In health risk assessment on Chinese people, reference of exposure factors(eg. inhaltaion rate, surface area etc.) from USEPA exposure factors handbook are often used. This may cause bias to the evaluation results by the different shape, activities and behaviors between different people. The purpose of this paper is to study four kinds of commonly used exposure factors (inhalation rate, ingestion rate, surface area and body weight ) of Chinese people based on the current national-wide surveys in China and relevant literatures. Results showed that inhalation rates of Chinese people with different ages are ranged from 5.71 to 19.02m3/day.The inhalation rate in male and female adults from 18 to 45 years old

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under three types of activity modes (mild, moderate and severe intensity) were between 13.5~16.7 m3/d. Daily dietary intake of Chinese adults is 1176.3g,among which ingestions from rice and flour product is 23% and 13% of the total daily dietary intake respectively. Body surface area of Chinese adults is 1.697m2 in male and 1.531m2 in female. Body weight of Chinese adults is 62.7kg among male and 54.4kg among female. There appears about 2.5~33.3% difference of exposure factors between Chinese and American people. To use exposure factors suitable for Chinese people while evaluating their health risks caused by environmental pollutants is very necessary.

2009-A-473-ISES

Updates To United States Environmental Protection Agency Standard Operating Procedures For Residential Pesticide Exposure Assessments

M. T. Crowley; United States Environmental Protection Agency, Washington, DC

In the effort to develop more refined approaches for evaluating exposures associated with residential uses of pesticides, the U.S. EPA is currently updating its Standard Operating Procedures For Residential Exposure Assessment (i.e., Residential SOPs). The SOPs were first developed in 1997 (with slight modifications in 2001) and have been used in EPA's exposure and risk assessments for pesticides since that time. The current update has included extensive review of additional available data enabling refinements to various elements of the exposure assessment methods and calculation inputs. Additionally, the use of probabilistic modeling approaches have become more common and the revised SOPs will emphasize defining inputs in distributional contexts (where possible and appropriate) for such use. An overview of the ongoing revisions as well as a brief recap of comments received during review at the October 2009 FIFRA Scientific Advisory Panel (SAP) will be presented.

2009-A-464-ISES

Effect Of Training On Exposure Judgment

M. L. Vadali; University of Minnesota, Minneapolis, MN

Results are presented from a NIOSH-funded research study that looked at occupational exposure judgment capabilities of hygienists across a wide range of industries. Participating companies provided monitoring information on specific tasks. A total of 49 hygienists from 6 companies participated in the study, and 22 tasks were evaluated. The number of monitoring data points for tasks varied between 5 and 24. The AIHA exposure assessment strategy was used to make judgments on the probability of the 95th percentile lying in one of four exposure categories relative to the occupational exposure limit. After reviewing all available job/task/chemical information, hygienists were asked to provide their judgment in probabilistic terms. Both qualitative and quantitative judgments were

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recorded. In addition to task judgments, hygienists’ task experience and information on determinants like educational and statistical background, years of IH and exposure assessment experience, and measures of cognitive ability was also obtained using a questionnaire. Data interpretation training, with simple rules of thumb for estimating 95th percentiles was provided to all hygienists. A data interpretation test was also administered, and all judgments were collected before and after training. Data was analyzed using SAS 9.1. The data interpretation scores increased from 48% to 67% after training (p < 0.001). The quantitative judgments improved from 46% to 69% (p < 0.001) post training. Some of the determinants that seemed to predict better judgment accuracy were the type of certification (CIH, CSP, IHIT), number of years an IH was using the AIHA strategy, and career air sampling surveys done. For quantitative judgments their statistical experience was also found to be a significant predictor. The study results suggest that the research should be continued to better understand the impact of determinants and training, and suggests use of statistical tools as an aid for quantitative judgments where limited data is available.

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Thursday, November 05, 2009

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Poster

R-P001a: Thursday: Air - Theme: Methods

2009-A-247-ISES

Development And Validation Of A GC/MS Method For Simultaneous Quantification Of Nine Alkylanilines In Air

I. Han, J. Groopman, T. Kensler, A. Geyh; Johns Hopkins Bloomberg School of Public Health, Department of Environmental Health Sciences, Baltimore, MD

Previous biomarker studies suggest that specific arylamine-hemoglobin adducts in peripheral blood are strongly associated with elevated risk for bladder cancer in non-smokers. Except for active smoking it is unclear what the airborne sources of arylamine are for general population. Potential sources of exposure for non-smoking individuals could be second hand smoke or occupational setting such as chemical manufacturing facilities. However, the challenges of detecting these compounds at low concentrations are significant. Studies which have measured a few of these compounds in the air report concentrations of 10-20 ng/m3. An analytical method has been developed for simultaneous measurement 9 alkylanilines (2,3-dimethylaniline [2,3-DMA]; 2,4-DMA; 2,5-DMA, 2,6-DMA; 3,4-DMA; 3,5-DMA; 2-ethylaniline [2-EA]; 3-EA; 4-EA) from measurements of personal exposure to these compounds. We simultaneously analyzed nine alkylanilines using GC/MS selective ion mode (m/z=106, 121, 77, and 65 for both DMA and EA groups, respectively). The chromatographic separation was achieved on Rxi-5ms (0.25um x 0.25mm x 30m) capillary column by optimizing temperature program from 50°C to 120°C at 1.5°C/min, from 120°C to 280°C at 30°C/min. The validation of the method was carried out for specificity, linearity, limit of detection, limit of quantification, recovery rate, and precision. The linearity ranged from 0.025ug/ml to 4.9ug/ml. The limit of detection ranged from 0.02ug/ml to 0.11ug/ml. The estimated optimum limits of quantification (or method detection limit) ranged from 0.53ng/m3 to 1.21ng/m3 for nine alkylanilines in air assuming an 12-hr sample at 200mL/min. Recovery rates ranged from 89% to 118% from spiked samples. Precision for each alkylaniline was <12 %. Given these results, the method can be used for exposure assessment to alkylanilines in the work places and in the general environment. Future studies will optimize the sampling device and personal exposure assessment protocol for airborne alkylanilines. Supported by NIH grants ES003819 and ES006052.

2009-A-560-ISES

Developments In Micro-scale Emission Chambers And Thermal Extraction For The Rapid Screening Of Emissions From Materials

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P. G. Hughes; Markes International Ltd., LLantrisant, United Kingdom

Emissions of (semi-)volatile organic compounds ((S)VOC's) and formaldehyde from materials can adversely impact indoor and in-vehicle air quality. European and international regulations/protocols, such as the European Construction Products Directive, German protocol for fire-resistant floorings (AgBB) and the Californian CHPS protocol for public school building programs (CHPS) require the determination of VOC’s and formaldehyde released from materials using conventional test equipment, such as chambers/cells, followed by thermal desorption / gas chromatography or high performance liquid chromatography respectively. These approaches enable emissions to be evaluated under simulated real-use conditions thus allowing real-room concentrations to be estimated. However, these approaches are often time consuming and expensive. This paper will report the recent development of a combined Micro-Chamber / Thermal Extraction technique which provides rapid and effective monitoring of up to 6 samples simultaneously for; -the evaluation of material emissions under simulated real-use conditions -elevated temperature content testing -VOC and formaldehyde content and surface materials emissions testing -the detection of banned compounds (eg. phthalates, biocides etc.) used within the production / processing of goods and materials This paper describes a novel approach for monitoring (S)VOC’s and formaldehyde released from a variety of materials using the Micro-chamber / Thermal Extractor. This paper will also report a novel application for the detection of formaldehyde and (S)-VOC's using direct thermal desorption.

2009-A-326-ISES

Application Of A Longitudinal Experimental Design To Determine The Cardiovascular Effects Of Ambient Air Pollution

J. P. Ramos-Bonilla, P. N. Breysse, F. Dominici, A. Geyh, C. Tankersley; Johns Hopkins University - School of Public Health, Baltimore, MD

Introduction: Inhalation toxicology studies involving animals have traditionally used high air pollution concentrations followed by the assessment of acute health outcomes. Few animal studies have analyzed the association between heart rate (HR) alterations and prolonged exposures to “real-world” air pollution concentrations. Objective: Develop a novel experimental design to expose animals to real-world air pollution concentrations over extended periods of time, continuously measuring the exposure to air pollution and the animals physiological outcomes. Methods: Aged AKR/J inbred mice were exposed to ambient air, 6-hr daily for 40 weekdays. Animals’ electrocardiograms (ECG) were continuously registered using telemetry, and air pollution concentrations were continuously measured using direct reading instruments. Animals’ HR and heart rate variability (HRV) were estimated from the ECGs.

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Results: Our experimental design exposed the animals to a well characterized mixture of pollutants. Applying random effect models, we observed a statistically significant 10% decrease in HR for every 1 ppm increase in carbon monoxide (CO), analyzing the association at the same day. Significant decreases in HR were also found 3 days after CO exposure, and for a 7-day CO cumulative effect. Similarly, statistically significant decreases at different time lags were observed between CO and HRV, between particulate matter and HRV, and between nitrogen dioxide and HR. Conclusions: We found that exposure to real-world air pollution concentrations was significantly associated with HR alterations. The novel experimental design had several advantages over traditional toxicological experiments, including the use of a reduced number of animals to achieve the desired statistical power, the ability to analyze different exposure lags, and a better representation of human exposure conditions.

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Poster

R-P001b:Thursday: Air - Theme: Exposure Modeling

2009-A-484-ISES

High-risk Zone Of Trichloroethylene Exposure In Middlesex County (new Jersey) Using Bayesian Maximum Entropy

M. Hasan,1 M. Serre,1 J. MacDonald,1 G. Carter2; 1University of North Carolina, Chapel Hill, Chapel Hill, NC, 2New Jersey Department of Environmental Protection, Trenton, NJ

Bayesian Maximum Entropy utilizes the spatial and temporal correlation observed between values of a variable at space-time points, p, to estimate values of that variable at unknown space-time locations. This paper presents a spatiotemporal analysis of trichloroethylene (TCE) concentrations in a heavily industrialized section of Middlesex County, New Jersey. TCE is a known animal carcinogen and a probable human carcinogen. Exploring the presence in parts per billion (ppb) of TCE across the study area’s time and space may give county officials a better understanding of how to protect its residents from TCE exposure. TCE contamination in Middlesex County was found to be both spatially and temporally correlated. The temporal correlation was stronger, that is, TCE contaminated sites remain highly concentrated over a long period time if no clean-up action is taken. The research then identified the high-risk zone for TCE contamination in Middlesex County. Future research could identify the sources of the TCE contamination and determine which populations are most highly affected.

2009-A-256-ISES

Mixing Of A Point Source Contaminant Within A Room: Fluctuating Speed Is A Proxy For Mixing Time And Estimation Of Turbulent Diffusion Coefficients

R. M. Jones,1 S. Dhakal,2 M. Nicas2; 1University of Illinois at Chicago, Chicago, IL, 2University of California, Berkeley, CA

Predicting human exposures to chemical and microbial airborne contaminants is simplified if the contaminant can be assumed to be uniformly mixed in the environment. The time scale of mixing processes, when considered with the time scales of contaminant and removal and exposure, can provide information about the validity of a uniformly mixed assumption. Direct measurement of the mixing time scale, or mixing time, is not always feasible, but may be inferred from indirect measures. We measured the mixing time of carbon monoxide subsequent to a bolus point release and quantified advective and turbulent flow using 3-axis ultrasonic anemometry in the core of a room-scale chamber under five mixing conditions. We found that fluctuating speed and fan power

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were significantly correlated with mixing time. Turbulence intensity was weakly related to mixing time, while mean speed was not correlated with mixing time. The experimental conditions were simulated with a Markov model of turbulent transport of gaseous contaminants and the three-dimensional diffusion equation. We used both models to estimate turbulent diffusion coefficients for the experimental conditions studied. When the Markov model was parameterized with fluctuating speed, the fluctuating speed parameter values that reproduced the measured mixing time were highly correlated with the measured fluctuating speed values. The unique and useful results of this study are the identification of fluctuating speed as an indicator of mixing time, and estimation of turbulence parameters for use in multi-zone models for exposure assessment, when the assumption of uniform mixing is invalid.

2009-A-378-ISES

Development And Evaluation Of Land-use Regression Models For New Haven, Connecticut Using Coupled Air Quality Model Concentrations

M. M. Johnson, V. Isakov, J. S. Touma, S. Mukerjee, H. Ozkaynak; U.S. Environmental Protection Agency, Research Triangle Park, NC

Land-use regression (LUR) models have emerged as a preferred approach for estimating individual exposure to ambient air pollution in epidemiologic studies. Although there is a growing literature focused on LUR evaluation, further research is needed to identify the strengths and limitations of LUR modeling and strategies for improvement. We developed and evaluated LUR models for nitrogen dioxide (NO2), benzene, particulate matter (PM2.5), and formaldehyde using year round daily air pollution estimates from coupled regional (CMAQ) and local scale (AERMOD) air-quality (AQ) models in New Haven, Connecticut. Daily concentrations were predicted for pollutants of interest using coupled AQ models. We combined predicted pollutant concentrations with land-use variables for 318 census block groups in New Haven. We developed seasonal and annual LUR models that varied in the number of sites used for model development. We compared models built using random site selection with models developed using a systematic approach to select representative locations. We also considered transferability of models across seasons by pollutant. There was a wide range of pollutant concentrations across the study area. Coefficients of variation (CV) were 78% for NO2 and benzene, and 50% for formaldehyde. PM2.5 displayed the least variability (CV=20%). Predicted pollution levels were highest in the city center and near port areas and highways. There was also a wide variation in traffic, industrial sources, and other land-use variables; of the 44 predictors, 95% had CV>30%. LUR research is limited by resource constraints because monitoring data are typically required for numerous sites. We linked LUR approaches with coupled regional-local scale models to evaluate and improve LUR techniques. Coupled AQ models could provide a cutting-edge tool for improving LUR estimates of exposure to ambient air pollution in epidemiologic studies. This is an abstract of a proposed presentation and does not necessarily reflect EPA policy.

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2009-A-244-ISES

Stochastic Estimation Of Green House Gases And Non- Green House Gases Contributors To Climate Change Using A Simultaneous Equation Model

S. S. Hati; Gombe State University, Gombe, Nigeria

A simultaneous equation model was developed in this work to estimate the total actual causes of climate change. It reviewed several past and current developments concerning the issues of climate change, including the most reliable documents provided by the Intergovernmental Panel on Climate Change (IPCC). Therefore the model considered several variables within a two components system of simply simultaneous equation, in which one part, is called the evolution equation and the other part called the response equation. The evolution equation considered variables that fitted the question that: at this time of the earth’s existence, without green house gases, would there be climate change? While the response equation considered variables that are potential activities capable of triggering natural responses, according to natural principles, in its ways to maintain harmonious equilibrium in matter. This included several variables such as the green house gas emissions and other forms of emission in which human population played an exponential role. However, in solving both equations simultaneously with ratio apportionment, it was found that green house gases contributed less than 20% of the total variables responsible for the total actual cause of climate change. This approach is novel, scientific and simple with realistic clarity. Hitherto, considerations for non green house gases as possible contributors to climate change was not made, which this approach tries to address successfully.

2009-A-343-ISES

Comparison Between Monitoring And Dispersion Modeling Approaches For Source Attribution In Brooklyn, Ny

L. M. Zwack, C. J. Paciorek, S. R. Hanna, J. D. Spengler, J. I. Levy; Harvard School of Public Health, Boston, MA

Evaluation of the public health benefits of mobile source control strategies requires an understanding of the relationship between traffic emissions and concentrations. However, in and around urban settings with elevated bridges, depressed roadways, and other complex terrain, this relationship is highly variable and difficult to model accurately. Regression-based approaches utilizing continuous real-time monitoring have been able to characterize this relationship on a small scale. However, such models may not generalize to other geographic areas, complicating their application across a large city. Atmospheric dispersion models are more commonly used to analyze the relationship between emissions and concentrations, but characterizing emissions at high resolution is challenging, and some dispersion models will not perform well in complex urban terrain.

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The goal of this study is to determine the extent to which statistical models derived from air pollutant monitoring observations collected in the neighborhood of Williamsburg, NY capture similar spatiotemporal relationships as advanced dispersion models. We apply the Quick Urban & Industrial Complex (QUIC) model, a computational fluid dynamics-like model that can take into account the presence of buildings and other terrain. QUIC is comprised of a 3D wind field model, a pressure solver, and a transport and dispersion model. The outputs of this model were compared to the outputs of statistical models for 1-minute averaged concentrations of ultrafine and fine particles, which characterized measured concentrations throughout Williamsburg as a function of traffic volume, meteorological characteristics such as wind speed, and distances from the two major air pollutant sources in the area, the Williamsburg Bridge and the Brooklyn-Queens Expressway. The QUIC model demonstrated similar concentration gradients arising from the same roadways, but with differences in patterns across time and space. This comparative analysis illustrates the strengths and weaknesses of two key modeling approaches and provides insight about areas in which both can be refined.

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Poster

R-P001c: Thursday: Air - Theme: Exposure Issues

2009-A-372-ISES

Personal Heat Budget And Its Effects On Exposures To Ambient Air Pollutants

Q. Meng, J. Pinto; National Center for Environmental Assessment, U.S. EPA, RTP, NC

Evaluation of the health risks associated with the change in meteorological parameters is crucial for understanding the effects of climate change on human health. The assessment of personal exposure to heat and cold is still a research gap. Meteorological parameters can also affect human health indirectly through modifying personal exposure to ambient pollutants (e.g. through personal activity patterns). In this work, effects of meteorological parameters on personal exposure to heat, cold and ambient pollutants are examined using data from the RIOPA study. In addition to pollutant measurements, 48-h average indoor and outdoor temperature, relative humidity, and air exchange rate were measured in 601 homes in Houston (TX), Los Angeles (CA), and Elizabeth (NJ). Meteorological parameters were collected from nearby National Weather Service stations. Results show that ambient temperature measured at central weather stations is a good indicator of residential outdoor temperature, with an R2 of 0.92. However, for days when heat index (HI) is applied (dry bulb temperature > 27 C, and relative humidity > 40%), the central site HI can only interpret 18% of the variations in residential outdoor HI, indicating that spatial variations in relative humidity were significant. When outdoor temperatures were in the range of -6 C to 33 C, a nonlinear association between indoor and outdoor temperatures was observed. The time people spent outdoors is a bell-shaped function of outdoor temperature, with the peak fraction of time spent outdoors (5.5%) occurring at 48 hour average temperature of 22 C. However, there were large differences between daytime maximum and nighttime minimum temperatures during the sampling periods. Personal heat and cold exposure will be stratified by exposure factors, using various physiological based indices. Feedbacks of ambient meteorological parameter changes on personal activities will be further characterized using categorical regressions. (This presentation does not necessarily reflect EPA policy)

2009-A-438-ISES

The Use Of Henry's Law To Estimate Formaldehyde Inhalation Exposure Concentrations For The United States Environmental Protection Agency Reregistration Review Process.

S. M. Arnold, D. D. Fontaine; The Dow Chemical Company, Midland, MI

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Biocides are a necessary ingredient in professional and consumer products to control microbial growth and extend product shelf-life. In 2008, the US Environmental Protection Agency (USEPA) Office of Prevention, Pesticides, and Toxic Substances Antimicrobial Division developed a risk assessment for registration of a formaldehyde-releasing biocide. As part of their risk assessment for consumer use of laundry detergents, USEPA used the vapor pressure of 1 mmHg, which is the vapor pressure of formalin (37% formaldehyde in aqueous solution), to estimate inhalation exposure to formaldehyde emitted into air. The use of this high, upper limit equilibrium vapor concentration gave an inhalation exposure estimate that was higher than deemed acceptable by USEPA. Since the maximum concentration of formaldehyde “generated” in solution from the formaldehyde-releasing biocides in professional and consumer products are on the order of 0.01% to 0.08% (depending on many factors such as the active ingredient concentration and product formulation), the vapor pressure of formaldehyde will be much lower than the 1 mmHg the USEPA used for their exposure assessment. This paper presents the basic physical-chemical properties of formaldehyde solutions and describes a simple relationship to estimate the vapor pressure of formaldehyde above dilute solutions using the Henry’s law constant reported by USEPA of 3.3E-07 atm-m3/mol. Based upon the assumed maximum range (assuming 100% conversion) of formaldehyde in solution (0.01% to 0.08%), the vapor pressure ranged from 0.0009 to 0.0068 mmHg. This range of vapor pressures was then substituted into USEPA’s risk assessment for laundry detergent to give exposure concentrations of 0.08 ppb to 4 ppb, compared to the 450 ppb USEPA derived for the vapor pressure above a solution containing 0.08% formaldehyde.

2009-A-474-ISES

Side By Side Comparison of Two Ultrafine Particle Counters Measuring Ambient Particulate Matter

L. M. Polyak,1 A. M. Rule,1 J. S. Kesavan,2 A. S. Geyh,1 J. N. Mihalic,1 I. Han,1 J. P. Ramos-Bonilla,1 P. N. Breysse1; 1Johns Hokins University, Baltimore, MD, 2US Army Edgewood ECBC, Aberdeen PG, MD

Measurements of particle size distributions across multiple locations can provide critical information needed to better assess human exposure to particulate matter. This is especially true for ultrafine (UF) particles which are poorly characterized in ambient air. In an ongoing study, we are monitoring ambient PM in cities across the US. This paper compares the UF particle size characteristics of ambient PM using two different instruments, a scanning mobility particle sizer (SMPS) and an electrical low pressure impactor (ELPI). Both instruments measure ultrafine PM using different principles of operation. The SMPS is based on electrical mobility and the ELPI measures aerodynamic diameter. Particle size measurements were obtained at a state-run air quality monitoring station outside Minneapolis, MN. The site was located in an open field (at the edge of a small county airport). Measurements were made with the SMPS (167 channels from 17 to 980

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nm) and ELPI (13 channels from 29 nm to 20 um) during a 10-day period in 5-minute increments. Only overlapping data (28 to 980 nm) were analyzed. Temporal changes in PM concentration reported by the instruments are highly correlated. However, the total number concentration reported by the SMPS is twice that reported by the ELPI. While the number concentrations were different, the Count Median Diameter (CMD) and Mass Median Diameter (MMD) were similar. The overall CMDs were 69 nm (GSD 1.90) and 56 nm (GSD 2.16) for the SMPS and ELPI, respectively. The MMD was 237 nm for the SMPS and 329 nm for the ELPI. As interest in health consequences of ultrafine particles grows, it is important to be aware of the advantages and limitations of the available instruments. Further research is required to ascertain which of the many characteristics of UF particles are the best predictor for health effects.

2009-A-280-ISES

Vertical Profile Of Airborne Particulate Matter Concentration And Ion Compositions Around Multi-story Residential Buildings In Tianjin

Z. Jiefeng; College of Environmental Science and Engineering of Nankai University, Tianjin, China

The main objective of this study is to determine 24-h integrated mass concentration and ion compositions of airborne particulate matter at different heights of two typical multi-story residential buildings in Tianjin, both naturally ventilated but within different distances from main road. Outdoor PM2.5 and PM10 samples were collected using PEM impactors (flow rate 10 L/min) and PQ200 instruments (flow rate 16.7 L/min) during three consecutive non-heating months; important meteorological parameters (i.e. ambient temperature, relative humidity, atmospheric pressure) were also concurrently measured at the sampling locations. A total of 120 Teflon samples were obtained for mass and chemical analysis of anions/cations (i.e. SO4

2-, NO3-, Cl-, NH4

+, K+, Ca2+). Results come out that daily concentration of PM2.5 and PM10 varied between a range of 57.8~163.1μg/m3 and 26.1~89.0μg/m3 due to diverse weather conditions with a long-term average concentration of 119.3 and 57.0μg/m3, respectively. Vertical variability of 24-h integrated mass concentrations of outdoor PM10 and PM2.5 was relatively week around the two multi-story buildings as measure height increased, however both PM2.5/PM10 ratios and ion compositions are remarkably traffic-related at low height level and affected by secondary particles at high level. Therefore, vertical profile of PM including various components should be considered carefully to meliorate the precision of exposure measurements and epidemiologic studies.

2009-A-328-ISES

Characterization Of Fine Particulate Matter Components In Five Non-Residential Microenvironments

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K. W. Brown,1 J. A. Sarnat,2 P. Koutrakis1; 1Harvard School of Public Health, Boston, MA, 2Emory University Rollins School of Public Health, Atlanta, GA

Previous studies have focused on concentrations of fine particulate matter (PM2.5) and its components in outdoor air as well as in homes and workplaces. Less attention has been focused on other microenvironments in which individuals spend time during a typical day. The Sources and Composition of Particulate Exposures (SCOPE) study entailed 8-hour measurements on seven consecutive days in six microenvironments in Atlanta: a hospital clinic, retail store, restaurant, grocery store and vehicle. Sampling was carried out during summer 2006 and repeated during winter 2006-2007. Development of a novel sampler allowed for detailed measurement of PM2.5 composition--elemental carbon (EC), organics and elements--combined with temporally resolved PM2.5 and ultrafine particles (UFP). During both seasons, locations with combustion sources_grocery, restaurant and van_had the highest levels of PM2.5, EC and OC. Comparisons were also made to ambient site concentrations of these pollutants. Relatively low indoor-ambient sulfur ratios for the grocery store, for example, contrasted with higher ratios of PM2.5, EC, and OC in that location, indicating significant contribution from indoor sources. The lowest concentrations for all pollutants were found in the hospital and retail store. Continuous PM2.5 and UFP were significantly elevated during events in the grocery store and restaurant. PM2.5 concentrations above 100 µg/m3 were found for several extended events in the restaurant and van during summer. Concurring with these events, UFP were also elevated (generally peaking before PM2.5), exceeding 100,000/cc with the highest UFP concentrations exceeding 300,000/cc. High concentrations measured in the restaurant, vehicle and grocery store pose a significant exposure, even if only for short periods of time. For the workers and patrons in the restaurant and grocery store, these exposures could significantly affect their health. Identification of sources and controls in these locations may allow for better protection of workers’ and patrons’ health.

2009-A-289-ISES

Geospatial Technologies To Improve Air Pollution Exposure Assessment

N. Kumar,1 K. Bocskay2; 1University of Iowa, Iowa City, IA, 2Chicago Dept of Public Health, Chicago, IL

Modern advances in geospatial technologies allow us to compute air pollution exposure at high spatial-temporal resolutions, say point location onto the geographic space on any given day. The proposed research examines the effects of ambient exposure (computed with the aid of geospatial technologies) to criteria pollutants on birth outcomes (birth weight, pre-term delivery and intrauterine growth restriction) in the Chicago Metropolitan Area from 2000 to 2004. The mothers’ exposure was computed at the place of their residences for the entire gestation period and for different trimesters using spatial-temporal dynamic modeling. Three important findings emerge from this work.

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First, PM10, CO, O3 and Pb exposure during different trimesters are significant predictors of birth outcomes. Second, the risk associated with criteria pollutants changes as the spatial-temporal scales used for computing exposure change. Finally, the birth outcome risks of high resolution air pollution exposure are significantly different from that computed using the conventional county level aggregated datasets.

2009-A-333-ISES

Have The U.S. Automobile Drivers “Going Green” Made An Impact On Greenhouse Gases

J. D. Roberts; Exponent, Wood Dale, IL

The Intergovernmental Panel on Climate Change (IPCC) considers carbon dioxide the most important anthropogenic greenhouse gas and stated in 2001 that “the present atmospheric carbon dioxide increase is caused by anthropogenic emissions of carbon dioxide”. As a result many efforts to mitigate the effects of climate change often focus on a reduction of carbon dioxide. This article will appraise the environmental impact of alternative fuel or hybrid vehicles over the past few years in the United States by assessing the emissions of greenhouse gases, specifically carbon dioxide. Although the U.S. Energy Information Administration recorded a 1.4% carbon dioxide emission reduction in 2006, as well as, a similar decrease in 2001, the carbon dioxide emissions attributable to transportation have continued to increase steadily. According to the U.S. Environmental Protection Agency’s “Inventory of U.S. Greenhouse Gas Emission and Sinks: 1990-2007” report, the carbon dioxide emissions from fossil fuel combustion of only the transportation sector since 1990 has increased by 27%. With over 250 million motor vehicles on the road in the United States resulting in nearly one-third of the country's total annual carbon dioxide emissions, this article will also examine the required number of conventional car exchanges for alternative fuel or hybrid vehicles in order to achieve 1990 carbon dioxide emission rates or even a compelling reduction attributable to transportation.

2009-A-334-ISES

The Incentives And Deterrents Of Choosing An Alternative Fuel Or Hybrid Electric Vehicle

J. D. Roberts; Exponent, Wood Dale, IL

As delineated by the Energy Policy Act (EPACT) of 1992, the United States Department of Energy (DOE) currently recognizes four types of alternative fuel vehicles (AFVs), one “additional alternative fuel blend-capable vehicle” and three other “advanced vehicles” (e.g. hybrid electric vehicle). The EPACT of 1992 also recognized seven alternative fuels, which are all fuels that have been and are currently commercially available for

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vehicles: (1) biodiesel; (2) electricity; (3) ethanol; (4) hydrogen; (5) methanol; (6) natural gas; and (7) propane. While the purchase or use of an AFV or hybrid electric vehicle in the United States has been considered by many to be the quintessential symbol for "going green" and a technological step forward, it has been determined that not all alternative fuel or hybrid vehicles function the same and consequentially may present more deterrents than incentives for some thereby impacting the full potential for a significant reduction in carbon dioxide emissions, greenhouse gases and a greener future. Hence, these deterrents will be examined and evaluated closely, in addition to addressing the question of whether or not AFVs or hybrid electric vehicles are truly a remedy to abating greenhouse gases or whether they are just shifting the problem.

2009-A-339-ISES

Role Of Community Groups In Municipal Extreme Heat Preparedness

M. Phillips, T. C. Wilcosky; RTI International, RTP, NC

During the 24-year period from 1979 to 2003, more people in the U.S. died from excessive heat exposure than died from hurricanes, lightning strikes, tornadoes, floods, and earthquakes combined. Although heat waves in the U.S. are already a significant public health concern, the problem is expected to worsen from the combined effects of global climate change, urbanization, and an aging population. Urban heat waves can be especially severe, because urban structures retain heat, and many low socioeconomic status families have neither air conditioning in the home or ready access to it. Moreover, heat warnings and advisories in the U.S. do not always reach the most vulnerable populations, who are often socially isolated. If a heat response plan is initiated, a lead organization such as the city health department or emergency response department must quickly mobilize. Additionally, volunteers and others from community groups should play a critical role: reaching out to the vulnerable populations. Because local community groups typically include those that provide services to the ethnic minorities, elderly, disadvantaged, homeless, and others, they are in a position to respond to the needs of the most vulnerable. Other organizations such as the American Red Cross, Citizen Corps, Neighborhood Watch, and Meals on Wheels could also support a heat response plan. Because each city is unique, a city-specific plan and training program would maximize the effectiveness of these volunteers. The method of communication (e.g., canvassing low income neighborhoods), as well as the message are critical for protecting the vulnerable populations. After a heat wave, the community groups’ efforts should be evaluated by the lead organization. If federal organizations and state and local health departments develop heat response plans community groups should play an important role.

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Poster

R-P001d:Thursday: Air - Theme: Personal Exposure

2009-A-258-ISES

Time-location Pattern Of A Population Living In An Air Pollution Hotspot

X. Wu, Z. Fan, P. Ohman-Strickland; EOHSI, Piscataway, NJ

The residents living in air pollution hotspots in Camden, New Jersey, i.e. the Waterfront South and Copewood/Davis Streets communities, are largely minority and impoverished population subgroup. Given the disadvantaged socioeconomic status, this subgroup may have different time-location pattern from the general public and may lead to a higher risk of exposure to air pollution. This study characterized the time-location pattern of 107 residents living in these two communities, and examined the variation of time-location pattern by employment status, location, season and day-type (i.e. weekday vs. weekend). Further, the time-location pattern of the Camden study cohort was compared with the National Human Activity Pattern Survey (NHAPS), which represents the time-location patterns of the U.S. general population. Employment status turned out to be the most influential factor in determining time-location pattern, and the variations of time-location pattern by season and day-type were also partially attributed to employment status. Given the low employment rate in these neighborhoods, a large number of residents, including children and unemployed adults, spent 93-100% (median) of their time in the neighborhood across seasons and day-types, leading to significant exposure to local air pollution. Comparison with the NHAPS showed that the Camden study cohort, i.e. the subgroup who lives in air pollution hotspots, spent significantly more time outdoors (3.8 hours vs. 1.8 hours) and less time indoors (19.4 hours vs. 20.9 hours) than the U.S. general population, and had potential for a higher exposure to ambient air pollution. Results from this study suggest that characterization of the exposure related time-activity patterns of the unprivileged population, who often live in highly polluted areas, is important for understanding exposure routes and potential sources for this subgroup and ultimately help develop effective strategies to reduce their exposure to ambient air pollution.

2009-A-283-ISES

Exposure Measurement To Volatile Organic Compounds In Personal Samples And Residential Microenvironments In Tianjin, China

J. Zhou, Z. Bai, J. Zhang, Y. You; China State Environmental Protection Key Laboratory of Urban Ambient Air Particulate Matter Pollution Prevention and Control, College of Environmental Science and Engineering, Nankai University, Tian jin, China

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Objective: Volatile organic compounds (VOCs) are an important class of outdoor air toxics because they are ubiquitous and associated with increased long-term health risks. VOCs are also an indoor air quality issue because humansspend, on average, nearly 90% of their time indoors. To date, personal volatile organic compounds (VOCs) exposure and residential indoor and outdoor VOCs levels have not been characterized in china. Methods: In this study, residential indoor and outdoor VOCs concentrations were measured and compared simultaneously with the personal exposure for each of 20 participants in tianjin, china. 16 VOCS were measured using passive samplers for 5 days in May 2008, and analyzed by using thermal desorber and GC-MS. Factors that influence personal VOCs exposures were assessed in relation to time activity information.Results\conclusion:. Study shows Participants spend over 85% of their times in indoors, and the main exposure sources are environmental tobacco smoke, paint emission due to indoor decoration, automobile exhaust according to time-activity information. Concentrations of most VOCs followed the general pattern outdoor < indoor <personal exposure across, except for Chloroform, heptane, carbon tetrachloride.

2009-A-358-ISES

Activity Pattern And Personal Exposures To Vocs In Korean Population

W. Yang,1 K. Lee2; 1Catholic University of Daegu, Daegu, Republic of Korea, 2Seoul National University, Seoul, Republic of Korea

Personal exposure is critical information to determine extent of risk and identify factors associated risk. Since personal exposure is affected by microenvironmental concentration and time activity pattern, we measured time activity pattern and personal volatile organic compounds (VOCs) exposures of about 400 subjects, along with microenvironmental concentrations such as residential indoors, residential outdoors and workplace indoors. The subjects were recruited in four different regions in Korea and the measurements were repeated in summer and winter. Time spent in indoor environments has been identified as a major contributor to the personal exposure. Personal exposures to VOCs were mainly affected by residential and workplace indoor concentrations and significantly correlated with the time activity weighted average of microenvironmental concentrations. Time activity pattern of the 400 subjects were compared with those of 32,000 subjects who was recruited from the entire countries proportional to the population distribution. The 32,000 subjects were asked to record in the time activity diary every 10 min of the day. Korea population spent the majority of their time indoors (87%), outdoors (5%) and in transportation (7%). Residential indoor time (59%) in Korea was different from those of western countries (about 65~75%). Korean also spent more time in indoors other than residence. This result can be explained by different culture and customs of Korean. Age, gender, working status, education and having children at home were significant determinants of their time activity. The assessment of health risk due to environmental contaminants depends upon accurate estimates of the distribution of population exposures. This exposure study can provide valuable information to understand population exposure and impact from exposure related behaviors.

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2009-A-381-ISES

Use Of Personal Monitoring Equipment In The Assessment Of Ambient Air Pollution Exposure

J. P. Ramos-Bonilla,1 R. H. White,2 R. Nachman,1 J. M. Samet,3 P. N. Breysse1; 1Johns Hopkins University - School of Public Health - Department of Environmental Health Sciences, Baltimore, MD, 2Johns Hopkins University - School of Public Health - Department of Health Policy and Management, Baltimore, MD, 3Johns Hopkins University - School of Public Health - Department of Epidemiology, Baltimore, MD

Introduction In recent years there has been an increase in the use of personal air pollution monitoring devices in epidemiological studies of the health effects of air pollution. The use of these devices improves the accuracy of estimates of personal exposures to ambient air pollution, and facilitates the understanding of the contributions of indoor and outdoor exposures to total personal exposure. Objective To review the use of personal monitoring equipment in studies that assessed human exposure to ambient air pollution, identifying sampling equipment currently available for these types of studies, and the performance of such equipment. Methods This systematic literature review was limited to recent studies that used personal monitoring equipment worn by the study participants to assess personal exposures to ambient air pollutants, including epidemiological studies of health effects associated with personal exposures. Validation studies of the performance of personal monitoring equipment were also included. Results The literature suggests that ambient PM2.5 concentrations correlate reasonably well with PM2.5 personal exposures. However, some studies have found low to moderate correlations and/or important differences in magnitude of exposure. There seems to be a growing use of portable direct reading instruments for particulate matter (PM) exposure in health studies, although most of the studies have used gravimetric devices. For gaseous pollutants, most of the devices used to monitor personal exposures are passive samplers. In general, studies have found that ambient gaseous concentrations are poor surrogates for personal exposures. Conclusions The availability of portable direct reading instruments, particularly for PM, brings a wide range of possible health effects research opportunities, especially because risks for many health outcomes are driven by air pollution exposures that vary over time and space. There is a clear need for the development of direct reading instruments that measure personal exposures to gaseous criteria and hazardous air pollutants.

2009-A-107-ISES

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Personal Particulate Matter And Gaseous Co-pollutant Exposures In An Asthmatic Cohort

R. Williams,1 A. Rappold,2 L. Delaine,1 M. Case,2 M. Schmitt,2 P. Jones,1 J. Thornburg,3 H. Daughtrey4; 1U.S. EPA, Research Triangle Park, NC, 2U.S. EPA, Chapel Hill, NC, 3RTI International, Research Triangle Park, NC, 4Alion Science and Technology, Research Triangle Park, NC

The US EPA is currently conducting an integrated exposure/epidemiological panel study involving mild to moderate and severe asthmatics. The study involves longitudinal repeated daily measures of personal and ambient-based coarse and fine particulate matter (PM10-2.5, 2.5) mass concentrations. These collections are being performed using a low burden active sampler developed by RTI International, the Coarse Personal Exposure Monitor (CPEM). Personal and ambient measures of gaseous co-pollutant data (nitrogen dioxide and ozone) are also being collected using passive dosimeters. The protocol involves the collection of five separate daily (24-hr integrated) monitoring events for each participants while they engage in their normal activities over a multi-week time period. Data reported at this time involves preliminary findings from half of the planned monitoring. Collocated personal and ambient-based PM samples reveal excellent agreement (r2 > 0.84). Matched daily personal to ambient sampling events resulted in very poor spatial agreement for PM2.5 (r2 = 0.01) and PM10-2.5 (r2= 0.04) mass concentrations. The median personal exposures to PM2.5 and PM10-2.5 were 18.5 ±16.5 and 9.8 ±10.7 µg/m3, respectively. Ozone measures revealed median personal exposures of 0.9 ± 4.2 ppb with median ambient levels of 36.7 ± 31.0 ppb. Median personal nitrogen dioxide exposures were determined to be 7.0 ±1.0 ppb. The r2 between matched personal and ambient nitrogen dioxide measures was only - 0.22 indicating the impact of non-ambient sources of this pollutant. Questionnaire data will be used to further define the initial exposure findings being reported here. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

225

Poster

R-P001e: Thursday: Air - Theme: Indoor Exposures

2009-A-431-ISES

Assessment Of Airborne Chemical Pollutants Levels In Paris Child Day Care Centers

C. Roda,1 M. Tribout,1 C. Dassonville,1 H. Ravelomanantsoa,2 Y. Le Moullec,2 I. Momas1; 1Université Paris Descartes. Laboratoire Santé Publique et Environnement-EA 4064, Paris, France, 2Mairie de Paris. Direction de l'Action Sociale de l'Enfance et de la Santé. Laboratoire d'Hygiène de la Ville de Paris, Paris, France

Background. Indoor air quality in child care facilities is poorly documented and infants spend around 30% of their time in these places. Objective. The aim of this study was to assess airborne chemical pollutants (aldehydes, volatile organic compounds-VOCs, nitrogen dioxide-NO2) levels in Paris day nurseries over one year. Methods. Twenty eight child day care centers were selected from facilities frequented by a random sample of babies who participate in the Paris cohort study. Airborne chemical pollutants were measured twice a year in the infant section for one week using passive devices. VOCs and NO2 were also measured outside the building. Comfort parameters and carbon dioxide levels were measured simultaneously. A standardized questionnaire was administered to gather information about the building and its population. Results. Indoor NO2 levels were significantly lower than outdoor levels whatever the season (30.7±1.3 µg/m3 versus 41.5±1.2 µg/m3, p<0.001) and indoor levels in cold season were higher than in warm season (34.1±1.3 µg/m3 versus 26.7±1.3 µg/m3, p<0.001) As for indoor aldehydes, they were detected in air of all buildings. Geometric mean levels of formaldehyde, butyraldehyde, hexanal, acetaldehyde, pentanal were 13.1±1.4 µg/m3

(range: 7.5-32.0), 10.4±1.3 µg/m3 (6.6-16.5), 9.5±1.6 µg/m3 (4.2-20.2), 5.4±1.3 µg/m3

(3.2-8.6), 1.8±1.7 µg/m3 (0.7-4.3). Except for acetaldehyde, levels were higher in warm season than in cold season (p<0.001). Aromatic and aliphatic compounds were also detected in air of all buildings. However, chlorinated compounds-tetrachloroethylene, paradichlorobenzene, trichloroethylene- were detected in 91%, 44% and 35% samples respectively. Indoor geometric mean concentrations of toluene, meta-paraxylenes, benzene, orthoxylene, ethylbenzene were 7.0±1.5 µg/m3 (range: 3.1-18.8), 4.1±1.7 µg/m3 (1.7-13.9), 1.8±1.4 µg/m3 (0.8-3.5), 1.4±1.7 µg/m3 (0.6-5.4)1.4±1.7 µg/m3 (0.6-4.4). Conclusion. This is the first study which assess indoor air quality in Parisian day nurseries. Results show that it is useful to take into account exposure in these places to estimate children’s exposure to chemical pollutants.

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2009-A-309-ISES

Characterization Of Indoor Particle Resuspension Due To Walking Activities

K. Cheng,1 M. Goebes,2 L. Hildemann1; 1Stanford University, Stanford, CA, 2Jay Hall and Associates, Annapolis, MD

The effect of indoor walking activities on particle resuspension was evaluated by associating non-prescribed foot traffic with simultaneous size-resolved particulate matter (PM) concentrations in a hospital in northern California. 15-min Foot traffic and PM measurements were taken in a hallway segment of the hospital over two continuous 27-hr monitoring periods. To examine the relationship between foot traffic intensities and the levels of different sizes of PM, an autocorrelation regression method, derived based on the indoor well-mixed box model, was used to consider the contributions of previous concentrations on subsequent measurements. The overall statistics from both monitoring periods showed that all size ranges of PM levels were highly correlated with the foot traffic measurements (p < 0.001) with R2 ranging from 0.87 to 0.90. However, correlations during the daytime subset of hours were consistently less significant than the nighttime subset. Coefficients found via this autoregressive analysis can be interpreted to reveal (i) time-independent contributions of walking activities on PM levels; and (ii) size-specific characteristics of the resuspended PM.

2009-A-407-ISES

Exposure To Secondhand Smoke In Public Places In Korea, China, Japan And Sri Lanka

J. Lee,1 K. Lee,1 X. Guo,2 H. Yamato,3 S. Nandasena,4 N. Sathiakumar5; 1Seoul National University, Seoul, Republic of Korea, 2Peking University, Pecking, China, 3University of Occupational and Environmental Health, Kitakyushu, Japan, 4University of Kelaniya, Kelaniya, Sri Lanka, 5University of Alabama at Birmingham, Birmingham, AL

This study aimed to assess fine particle (PM2.5) air pollution due to secondhand smoke (SHS) in public places in East Asian countries. This study conducted in Korea, China, Japan and Sri Lanka from December 2007 to March 2009. SHS concentration was measured by a TSI SidePak AM510 Personal Aerosol Monitor, using a calibration factor of 0.295. We chose target public venues which allowed smoking and different types of venue were included. The measurement conducted during busy business hour and each venue measured for at least 40 minutes. Numbers of people inside the venue and burning cigarettes at that moment were counted every 10 minutes. Smoking density of each venue was calculated as number of burning cigarette per 100 m3 of the venue. The average PM2.5 concentrations were 161 μg/m3 in Korea, 160 μg/m3 in Japan, 125 μg/m3 in Sri Lanka and 98 μg/m3 in China. Internet café in Korea has the highest PM2.5 levels (392 ± 246 μg/m3). Entertainment venues of Japan (pachinko and bowling) and Sri Lanka (country club and pool parlor) showed the highest average PM2.5 concentrations among

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types of venue (Japan 184 ± 127 μg/m3, Sri Lanka 225 ± 55 μg/m3), and singing room showed highest concentration in China (221 ± 159 μg/m3). Except one type of venue in China (bath room 32 μg/m3), all of venues exceeded 35 μg/m3 which is 24hr ambient PM2.5 standard of US EPA. There was a positive relationship between smoking density and indoor PM2.5 concentration. This study provides evidence that people in some East Asian countries can be exposed to relatively high PM2.5 concentrations at public places due to secondhand smoke. To reduce secondhand smoke exposure, some efforts such as a comprehensive smoke-free law in public places are needed.

2009-A-448-ISES

Fine Particle (PM2.5) Air Pollution Due To Secondhand Smoke In Selected Public Places Of Sri Lanka

Y. Sumal Nandasena,1 A. Wickremasinghe,1 K. Lee,2 N. Sathiakumar3; 1Department of Public Health, Faculty of Medicine, University of Kelaniya, Ragama, Sri Lanka, 2Graduate School of Public Health, Seoul National University, Seoul, Republic of Korea, 3Department of Epidemiology, School of Public Health, University of Alabama at Birmingham, Birmingham, AL

Introduction: Annually, 5 million deaths could be attributed to tobacco smoke. Secondhand smoke accounts for a considerable proportion of deaths due to tobacco. Enactment and enforcement of legislation for all indoor workplaces and public places to be 100% smoke-free is recommended. In Sri Lanka, non-smokers are exposed to tobacco smoke at various public places despite the existence of legislation (National Authority on Tobacco and Alcohol Act (No. 27 of 2006) of Sri Lanka). Objective: To determine concentrations of fine particles (PM2.5) due to smoke in selected public places where smoking occurs in Colombo, Sri Lanka. Methods: PM2.5 levels in 20 public places (restaurants, n=6; bars, n=6; cafés, n=4; entertainment venues, n=4) were measured using the PM monitor (Model AM510 - SIDEPAK Personal Aerosol Monitor). Different types of businesses were selected and selection of monitoring venues was not random. Public places were defined as a space, which can be visited without permission. Air quality was measured indoors for 40 minutes and in the immediate outdoors for 10 minutes before and after the indoor measurement. Data were collected from January to March of 2009. Results: Average indoor PM2.5 ranged from 42 to 299 μg/m3. Average outdoor PM2.5 ranged from 18 to 83 μg/m3. Indoor to outdoor PM2.5 ratio (I/O) ranged from 1.05 to 14.93. The highest PM2.5 concentration was observed from a bar although the smoking density (1.52 bc/100m3) was lower than in some other venues. The highest I/O ratio was reported from an entertainment venue having a low smoking density (0.81bc/100m3). The lowest I/O ratio was recorded from a bar. Conclusions: All indoor locations had higher PM2.5 levels as compared to their immediate outdoors. The importance of improving ventilation and enforcing the law to stop smoking in public places is highlighted.

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2009-A-351-ISES

The Effects Of Proximity On Exposure: Examining The Uniform Mixing Assumption For A Point Source

V. Acevedo-Bolton, K. Cheng, R. Jiang, W. Ott, N. E. Klepeis, L. M. Hildemann; Stanford University, Stanford, CA

Most existing indoor air quality models assume uniform mixing. This will tend to underestimate a person’s exposure to a pollutant if they are near an emission source - since mixing is not instantaneous, the uniform mixing assumption does not adequately describe concentration levels near a source while emissions are occurring. To characterize the proximity effect, we performed 16 controlled experiments in two homes using tracer gases released from a point source. CO was released for 5 to 12 hours per experiment while an array of up to 41 CO monitors surrounded the source at different angles and distances. Monitors were placed at source height (1 m) and at horizontal distances of 0.25 m to 5 m from the source. For a few experiments the source was moved between 0.5 m to 1.25 m to measure vertical mixing of the pollutant. Window positions within the house were varied to test the effect of different ventilation rates, which were quantified using the decay of SF6. Results showed that shape of the proximity curve (average CO concentration as a function of radial distance from the source) flattened as the air change rate decreased. Thus, the proximity effect was most pronounced when the air exchange rate was high. Moving the CO source above or below the plane of the monitors diminished the proximity effect, suggesting that vertical mixing was greatly inhibited. Our data showed that concentrations at close proximity to a point source could greatly exceed the uniform mixing assumption. For example, at the highest ventilation rate, we found that two people standing 0.25 m and 5 m from the source, respectively, could be exposed to 20 times and 2.5 times the predicted concentration assuming uniform mixing in the room. This shows that indoor exposure can vary greatly with distance from a point source.

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Poster

R-P001f: Thursday: Air - Theme: Indoor/Outdoor Exposures

2009-A-493-ISES

Employee And Patron Exposure To Pollutants In A Northern California Casino

V. Acevedo-Bolton, N. E. Klepeis, R. Jiang, K. Cheng, W. R. Ott, L. M. Hildemann; Stanford University, Stanford, CA

Indoor and outdoor measurements of pollutant levels were collected for six days over three weekends at the Win-River Casino, a 12,000 m3 (75,000 square feet) California Indian casino in Redding with 750 slot machines. With the full cooperation of management, we collected measurements at seven fixed locations of gravimetric fine particles (PM2.5), real-time PM2.5, and nicotine. We logged real-time personal exposure to PM2.5 every minute, placing portable monitors on four employees per night, along with 3-4 investigators who behaved like patrons. Personal measurements of cotinine, PAH, ultra-fine particles, CO2, temperature and relative humidity were also collected, and the number of people and smokers present were counted several times each night. Stationary particle monitors measured, on average, 55 ug/m3 in the smoking areas, 17 ug/m3 in nonsmoking areas, and 8 ug/m3 outdoors. The PM2.5 levels experienced by the pit boss, who spent his entire work shift on the floor, were the highest. His personal exposure (averaged over 6 hours of his work shift) was 65 ug/m3 which was almost twice as high as the EPA 24-hr standard of 35 ug/m3; his peak exposures reached up to 450 ug/m3. The indoor versus outdoor CO2 levels, along with patron counts, were used to estimate air change rates of 2 h-1-14 h-1, consistent with the reported HVAC data (4 h-1 to 16 h-1) and within ASHRAE standards. Using ventilation data and the casino volume, a mass balance model was used to evaluate how well the smoker-count data correlated with the indoor PM2.5 measurements.

2009-A-414-ISES

Residential Levels Of Indoor And Outdoor Ultrafine Particles In Winsor, Ontario

J. Kearney,1 L. Wallace,2 K. Van Ryswyk,1 R. Kulka,1 X. Xu,1 A. Wheeler1; 1Health Canada, Ottawa, ON, Canada, 2Consultant, Weston, VA

Ultrafine particles continue to be a significant point of interest with respect to the health effects of particulate matter. Few data on indoor and outdoor levels of ultrafine particles exist in Canada. As part of the Border Air Quality Strategy, Health Canada has conducted a series of exposure assessment studies investigating the relationship between personal, indoor and outdoor air pollutants in Windsor, Ontario. During 2005 and 2006, 48 non-

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smoking adults and 51 asthmatic children (aged 9-12 years), respectively participated in an exposure study, examining indoor and outdoor levels of ultrafine particles. At each participant’s homes, indoor and outdoor 30-second average levels were measured for 10 minutes each hour using a P-trak (TSI Inc.). Sampling was carried out for 5 consecutive days in summer 2005 and winter and summer 2006. Other measures included air change rate, temperature, and relative humidity. Information on daily activities, housing characteristics and proximity to traffic sources was also collected. Approximately 500,000 30-second average indoor and outdoor ultrafine measurements were collected and analysed. Median indoor particle counts were 2742 cm-3 (summer 2005), 2626 cm-3 (summer 2006) and 4130 cm-3 (winter 2006). Median outdoor particle counts were 10660 cm-3 (summer 2005), 6397 cm-3 (summer 2006) and 11063 cm-3 (winter 2006). Maximum levels were near the maximum reading of the P-Traks (500,000 cm-3). Ultrafine distributions displayed stronger indoor source strengths than for fine particles, with indoor concentrations exceeding outdoor values for about 20% of cases. The outdoor distributions of particle number showed a distinct change of slope at about the 98th percentile; reasons for this will be investigated, but perhaps indicate occasional "nucleation bursts" that have been characterized in other studies. Indoor and outdoor sources associated with the ultrafine measurements collected in this study will be identified and discussed.

2009-A-420-ISES

Associations Between Outdoor And Indoor Ozone Concentrations

P. Taimisto, T. Yli-Tuomi, P. Ahtoniemi, M. Loh, J. Pekkanen, R. O. Salonen, T. Siponen, T. Lanki; National Institute for Health and Welfare (THL), Kuopio, Finland

Epidemiological studies have associated elevated daily outdoor ozone concentrations with increased cardiorespiratory morbidity and mortality. However, it is unclear how outdoor ozone concentrations are reflected indoors. The goal of the study was to determine whether outdoor ozone concentration measured at a central site can be used to estimate the variation of ozone levels at home. The field study was carried out in a residential area of Kuopio, a town with 93 000 inhabitants in Finland, during the winter and spring 2008-2009. Indoor ozone levels were measured in the living rooms of 34 participants once a month (1-6 times). The maximum distance from the central site to a participant’s home was approximately 1.5 kilometers. Pearson correlations between daily averages of outdoor and indoor O3 concentrations were analyzed for 11 individuals separately and then the median was taken. Participants with fewer than four successful measurements were excluded. There are currently 45 valid indoor ozone measurements with corresponding outdoor data available. The average daily ozone concentrations were 4.7 µg/m3 indoors and 45.5 µg/m3 outdoors in wintertime. Springtime concentrations were 6.2 µg/m3 indoors and 74.2 µg/m3 outdoors. The median Pearson correlation between the indoor and the outdoor ozone concentrations was 0.566 (25th percentile -0.646 and 75th percentile 0.946). Our preliminary results suggest that central outdoor measurements of ozone can be used

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in longitudinal epidemiological studies to estimate daily changes in indoor ozone levels. It is unclear whether the low indoor ozone levels can be harmful to health.

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Poster

R-P001g: Thursday: Air - Theme: Remote Sensing

2009-A-376-ISES

Enhancing Environmental Public Health Tracking With Satellite-driven Particle Exposure Modeling And Epidemiology

Y. Liu,1 D. A. Quattrochi,2 J. Sarnat,1 J. Qualters3; 1Emory University, Rollins School of Public Health, Atlanta, GA, 2NASA Marshall Space Flight Center, Huntsville, AL, 3Centers for Desease Control and Prevention, Atlanta, GA

Characterizing population exposures to PM2.5 has emerged as a major environmental health initiative. Satellite aerosol remote sensing may help expand the coverage of PM2.5 monitoring to rural and suburban areas not currently located near ground-monitoring networks. The proposed study will examine the use of satellite aerosol remote sensing as a potential means to extend the coverage of the National Environmental Public Health Tracking Network at CDC. Specifically, using data from multiple NASA Earth sciences missions together with meteorology and land use information, this study aims at providing accurate, timely information on the temporal and spatial characteristics of PM2.5 concentrations through an advanced spatial modeling framework that can be used by CDC and its federal, state and local partners to support, and evaluate public health policy and practice related to health impacts of air pollution. This study will consist of three research components. Component A will integrate aerosol retrievals from MODIS, GOES, MISR, and OMI, meteorology, land use information, and EPA PM2.5 measurements over the 20-county metropolitan Atlanta area between 2000 and 2007. Component B will develop a spatial statistical model using this database to estimate daily PM2.5 exposures, and generate daily concentration estimates for the model grid. These estimates will be compared to Tracking Network’s two current methods of estimating PM2.5. Predictions will also be validated prospectively. Component C will incorporate the validated estimates in the largest single-city, U.S. time-series epidemiologic analyses examining the association between PM2.5 and cardiorespiratory emergency department visits and comparing the results to those generated using CDC’s current PM2.5 exposure estimation methods. Together, this study comprises the most comprehensive effort to use satellite remote sensing information in a public health tracking context, while leveraging an existing extensive network of air quality researchers and data.

2009-A-467-ISES

Within-urban Variability In Outdoor Nitrogen Dioxide Concentrations: Satellite Versus Ground-based Estimates

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M. J. Bechle, L. C. Ohman, K. Lundquist, D. B. Millet, J. D. Marshall; University of Minnesota, Minneapolis, MN

We compared two estimates for outdoor urban NO2 concentrations: satellite measurements and EPA ambient monitoring stations. The OMI sensor, aboard NASA’s Aura satellite, provides afternoon (~1:30p) measurements of total atmospheric column abundance. We used the GEOS-Chem global model of atmospheric chemistry and the CAMx urban airshed model to relate those column measurements to ground-level concentrations. Previous work has shown that satellite measurement error is lower in summer than in winter. Our study location is the South Coast Air Basin of California, during the summer (June-August) of 2005. We compared 1231 sets of paired data for 25 EPA monitoring stations. The satellite measurements include more data gaps than the EPA monitors (41% versus 5%, respectively), due to cloud contamination and other issues. Mean (standard deviation) concentrations are 6.0 (3.8) ppb for the satellite dataset and 16.3 (11.2) ppb for EPA monitoring data, a factor of 2.7 difference. Correlation (67%) and bias (52%) statistics also point to significant differences between the two measurements. Our results are consistent with earlier work showing that EPA monitors can overestimate NO2 measurements due to interference from other reactive oxidized nitrogen-containing species (NOz) such as peroxyacetyl nitrate (PAN) and HNO3. Satellite measurements offer several advantages (low marginal cost; global coverage). However, accounting for differing chemical specificity, data gaps, and diurnal coverage will be necessary if researchers wish to use satellite measurements in place of ground-based measurements. Hybrid methods may potentially employ strengths from each approach.

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Poster

R-P001h: Thursday: Air - Theme: Outdoor Exposures

2009-A-389-ISES

Difference In Characteristics Of Fine Ambient Particles Collected From Cities Across The United States

A. S. Geyh, J. N. Mihalic, I. Han, J. P. Ramos Bonilla, A. M. Rule, L. Polyak, P. N. Breysse; John Hopkins Bloomberg School of Public Health, Baltimore, MD

Ambient particulate matter (PM) concentrations have historically been regulated and monitored based on mass concentration. There is a growing body of evidence suggesting that health risks derived from PM exposure could be due to specific constituents. A study is currently underway to collect and characterize PM in US cities that have shown important differences on the health risks associated with PM exposure. Sampling campaigns were sequentially conducted in Seattle WA, Sacramento CA, Phoenix AZ, Houston TX, and Minneapolis MN between October 2007 and February 2009. Constituents included black carbon (BC), polycyclic aromatic hydrocarbons (PAH), and metals (Ni, V, Zn, Pb, and Mn). BC and PAH were measured using direct reading instruments. Bulk samples of coarse and fine PM were collected using a sequential cyclone system. Samples were analyzed for metals using ICP-MS. Total sampling time within cities ranged between five to seven weeks. Preliminary analysis suggests major differences in PM constituents between cities. For BC and PAH, the highest concentration were observed in Seattle (BCmean=1040.9 ng/m3; PAHmean=6.6 ng/m3), and the lowest were observed in Minneapolis (BCmean=287.7 ng/m3; PAHmean=0.66 ng/m3). Metal mean concentrations for the fine PM samples showed high variability between cities. Overall, the highest metal concentrations were observed in Mn (overall highest in Minneapolis, Mn=698.8 μg/g) and Zn (Phoenix, Zn=407.7 μg/g), with several fold differences in concentration between cities for some metals. The smallest range for the metals assessed in fine PM was for Pb ( below the detection limit to 42.1 μg/g). We observed major differences in PM constituents in PM samples collected from different US cities. Our findings could help explain why cities with similar mass concentrations of PM show differences in terms of the health risks associated with PM exposure. Linking the exposure data with epidemiological and toxicological studies could improve our understanding of this field.

2009-A-415-ISES

Estimation Of Spatiotemporal Distribution Of Fine Particulate Matter Exposure In Taipei City (Taiwan)

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H. Yu, C. Wang; National Taiwan University, Taipei, Taiwan

Many health studies have shown a significant association between PM exposure and healthy deficiency, such as premature mortality, respiratory disease (e.g., asthma), cardiovascular disease, and systemic inflammation. Among them, fine PM particles (PM2.5) are believed to be more dangerous to human health than PM10 because fine particles are easier inhaled and accumulated deeply into the lungs. It is crucial for the health agency to have knowledge about spatiotemporal distribution of PM2.5 exposure to people living in Taipei city, the largest metropolitan city in Taiwan where a variety of industrial or traffic emissions are presented. In Taipei city, several PM-related data, i.e. PM10, PM2.5 and Total suspended particles (TSP), have been collected separately by central and local governmental institutes during . Bayesian maximum entropy (BME) is theory of modern spatiotemporal modeling and mapping that includes concepts and techniques having a number of important features: they automatically incorporate non-linear estimators and non-Gaussian laws, integrate information at various kinds and scales, and account for a variety of uncertainty sources. This paper provides an application to assimilate PM-related information for the PM2.5 modeling in Taipei city by BME method. PM-related information includes hard and soft data for PM2.5, PM10 and TSP, as well as empirical information about PM2.5/PM10, PM10/TSP ratios. The empirical ratios can depend on environmental conditions, such as changes of land use or weather patterns, which can significantly vary across space and time. BME method is then applied to generate PM2.5 maps monthly over entire Taipei city during the period of 2004-2007. The maps can account for both observed data, i.e. PM2.5, PM10, and TSP, and empirical relationships among them under conditions of uncertainty. The spatiotemporal mapping of PM2.5 can be valuable to health administration in Taiwan governments to assess the spatial distributed long-term exposure risk over the city.

2009-A-424-ISES

Exposure Of Finnish Subpopulations To Fine Particles Due To Domestic Wood Combustion

P. Ahtoniemi,1 M. Tainio,1 N. Karvosenoja,2 K. Kupiainen,2 P. Porvari,2 A. Karppinen,3 L. Kangas,3 J. Kukkonen,3 M. Pohjola,1 J. Tuomisto1; 1National Institute for Health and Welfare, Kuopio, Finland, 2Finnish Environment Institute, Helsinki, Finland, 3Finnish Meteorological Institute, Helsinki, Finland

Previous studies have shown that primary fine particles (PPM2.5, particles with aerodynamic diameter < 2.5 µm) cause several adverse health effects including cardiopulmonary diseases and mortality. In Finland domestic wood combustion is second most important PPM2.5 emission source category after traffic. The exposure for domestic wood combustion related PPM2.5 emissions varies across the country and different subpopulations could be more exposed to these emissions. In this study we estimated different subpopulations exposure to domestic wood combustion related PPM2.5 with GIS methods. The PPM2.5 emission data for Finnish sources for year 2000 was based on

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the Finnish Regional Emission Scenario (FRES) model and the dispersion of PPM2.5 was estimated with the urban dispersion modeling system (UDM-FMI). The population data used in assessment was based on Statistics Finland Grid Database. The exposure was defined separately for different age and education subpopulations. The spatial resolution of the model was 1 km x 1 km. Average exposure to domestic wood combustion related PPM2.5 was between 0.5 to 0.6 µg/m3 for different subpopulations. The highest exposed subpopulations were highest educated and young adults. These subpopulations had higher population densities near the areas where secondary house heating with wood combustion was common. Variation of exposure between subpopulations in contrast to population average exposure (0.6 µg/m3) to PPM2.5 due to domestic wood combustion was relatively small. The significance of the observed exposure differences for adverse health effects can be explored with more detailed analyses, including uncertainty analysis.

2009-A-430-ISES

Assessment Of Particle-bound Polycyclic Aromatic Hydrocarbons Exposures For Two Sensitive Cohorts

S. C. Lung,1 L. Chang,2 C. Tang,3 H. Tu3; 1Academia Sinica, Taipei, Taiwan, 2Feng Chia University, Taichung, Taiwan, 3Fu Jen Catholic University, Taipei, Taiwan

Polycyclic aromatic hydrocarbons (PAHs) are formed by the incomplete combustion of organic matters and are distributed into the air in the vapor phase or the particulate phase through adsorption or condensation on the surface of respirable particles. It has been reported that PAHs ranked as probable human carcinogens are primarily associated with the particulate phase. Therefore, the characterization of exposure to particle-bound PAHs is critical to assessing the health risks in our daily life. A panel study was conducted during the years 2003 to 2005 to examine the health effects of particulate air pollution on susceptible populations. The current paper focuses on assessing exposures to particle-bound PAHs for both of school-age children with asthma and elderly people living within the metropolitan Taipei area. Panels consisted of 57 susceptible subjects, including 43 children and 14 elderly subjects. During the study, integrated personal exposure samples were collected by a dust monitor (model 1.108, Grimm, Germany) for PAHs analysis using gas chromatography/mass spectrometry (GC/MS). The sampling durations for the elderly and children were 24 hours and 5 days, respectively. As some of the subjects participated in two different sampling seasons, overall, 23 samples for elderly people and 52 samples for the children were included in the data analysis. All participants lived in private residences, where they also completed activity diaries to report information on the nature and location of their activities, as well as other factors (e.g., incense burning) that may affect personal exposures. Initial results showed that geometric mean concentrations of total particle-bound PAHs in the elderly were almost two times higher than those commonly found in children (23.1 and 12.8 ng/m3, respectively). On the other hand, the percentage of carcinogenic PAHs exposures was lower in elderly people, as compared to those in school-age children (53.2% and 70.7%, respectively).

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2009-A-457-ISES

Estimating 5-minute Average Sulfur Dioxide Exposures In Support Of The Environmental Protection Agency's Review Of The National Ambient Air Quality Standard: Application Of A New Version Of Apex To St. Louis MO

A. Rosenbaum,1 S. Graham,2 M. Huang,3 S. Vutukuru,4 J. Langstaff5; 1ICF International, Rohnert Park, CA, 2US EPA, Office of Air Quality Planning and Standards, Research Triangle Park, NC, 3ICF International, Fairfax, VA, 4ICF International, San Francisco, CA, 5US EPA Office of Air Quality Planning and Standards, Research Triangle Park, NC

The US Environmental Protection Agency (EPA) is conducting a review of the national ambient air quality standards (NAAQS) for sulfur dioxide (SO2), including an estimate of potential population exposure and associated health risk. Controlled human exposure studies have consistently demonstrated that exposure to SO2 for 5 to10 minutes can result in significant bronchoconstriction and/or respiratory symptoms in exercising asthmatics. However, SO2 exposure concentrations, derived either from personal exposure measurements or indirect means (e.g., ambient measurements or air dispersion model predictions), are generally available only for averaging times of one hour or longer. Therefore, a new modeling approach was needed to estimate 5-minute exposure concentrations. As part of the NAAQS review, exposures were estimated using US EPA’s Air Pollutants Exposure Model (APEX), a probabilistic model that simulates the movement of individuals through time and space to estimate exposure in indoor, outdoor, and in-vehicle microenvironments. A required input to APEX is a time series of hourly air quality concentrations. To estimate SO2 concentrations with a 5-minute averaging time, a new algorithm was incorporated into APEX to generate a time series of 5-minute maximum concentrations within each hour from the time series of hourly average concentrations. The algorithm uses 5-minute peak to 1-hour mean concentration ratios derived from a small set of monitors that record 5-minute maximum SO2 concentrations. This presentation discusses the development of the new APEX algorithm and its application to St. Louis MO for several air quality scenarios. For example, approximately 7% of asthmatic children in the urban core of St. Louis are estimated to experience at least one 5-minute daily maximum SO2 concentration at or above 100 ppb under 2002 air quality conditions while exercising. Results for several other concentration levels and air quality scenarios will be reported.

2009-A-567-ISES

Two Hundred And Fifty Micrograms/m3 Is The Safe Level Of The Total Volatile Organic Compounds Indoor Air

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E. Todaka,1 H. Nakaoka,1 M. Hanazato,1 C. Mori2; 1Center for Environment, Health and Field Sciences, Kashiwa, Japan, 2Graduate School of Medicine, Chiba University, Chiba, Japan

“Chemiless Town” is a model town built in a university campus, in which houses and buildings are built with chemicals as few as possible, so that sick-building syndrome (SBS) can be prevented. The tentative legal standard value for the TVOC (total volatile organic compounds) indoor air is 400 micrograms/m3 in Japan. However, there are people who diagnose SBS at this level. To prevent SBS, more strict and attainable level should be decided. In Chemiless Town, there are two rooms about the same size. The TVOC of one room is over 400 micrograms/m3 (Room A), and the TVOC of another room is less than 250 micrograms/m3 (Room B). Thirty-three healthy volunteers participated in the experiment. They were divided into two groups by answering QEESI (Quick Environmental Exposure and Sensitivity Inventory) questionnaire if they are sensitive to chemicals or not. Among them, 12 people showed sensitivity, and 21 people showed less sensitivity. They stay in each room for 15 minutes and answered the questionnaire if they had any symptoms. As the results, regarding the less sensitive people, there was no difference between the numbers of the subjects who showed any symptoms in room A or B. Only three people in each room showed some symptoms. However, there was clear difference among the sensitive group. In Room A, 8 out of 12 subjects showed some symptoms (67%), whereas in Room B, only 2 out of 12 subjects showed some symptoms (17%). In conclusion, indoor air TVOC should be as low as 250 micrograms/m3 to prevent SBS. From the result, NPO (Non Profitable Organization) Chemiless Town Association decided to certify the room in which TVOC is below 250 micrograms/m3 as the “Chemiless Room” that can prevent SBS for most of the people.

2009-A-240-ISES

Development Of A Predictive Model To Determine Variables Affecting Pollution Concentrations Near Heavily Traveled Roadways

K. H. Kozawa,1 S. A. Fruin,2 A. M. Winer3; 1California Air Resources Board, Sacramento, CA, 2University of Southern California, Los Angeles, CA, 3University of California, Los Angeles, Los Angeles, CA

Fixed site monitoring data used in compliance monitoring and in many health studies generally do not capture the high localized impacts observed near roadways. These impacts vary depending on meteorology as numerous studies have shown, but there has been little effort to characterize such impacts as a function of meteorology. In the current study, we exploit the high temporal and spatial resolution provided by a mobile platform and combine it with highly-time-resolved met data to investigate the most important variables determining near-freeway pollution concentrations of nitrogen oxide, particle-bound polycyclic aromatic hydrocarbons, black carbon, and ultrafine particle number. Data were collected for 19 days in two seasons during various meteorological conditions including sampling before and after rain events. Multiple regression analysis showed

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impacts within 150 meters of busy freeways with heavy diesel vehicle traffic can be well-predicted by a combination of relatively few, readily-available explanatory variables including: fraction of time downwind (at two-minute average wind directions) relative humidity wind speed time of day (a.m. or p.m.) and season (warm or cool), with an R2 of 0.70. Interestingly, data from the nearest fixed site monitor, about 3000 meters away, was a poor predictor of near-road impacts (R2 = 0.0). Furthermore, significant near-road impacts were often observed even when the vector-averaged wind direction indicated the sampling area was upwind of the freeway. This simple and straightforward model for predicting near-road impacts may be a useful alternative to dispersion models such as CALINE in assessing pollutant concentrations near heavily traveled roadways where local, time-resolved wind direction data are available.

2009-A-347-ISES

The Impact Of Wood Smoke On Ambient Pm2.5 In Northern Rocky Mountain Valley Communities

T. Ward; The University of Montana, Missoula, MT

The Impact of Wood Smoke on Ambient PM2.5 in Northern Rocky Mountain Valley Communities Tony Ward1* and Todd Lange2 1Center for Environmental Health Sciences, The University of Montana, Missoula, Montana; 2NSF-Arizona AMS Facility, The University of Arizona, Tucson, Arizona, *Corresponding Author: Tony J. Ward Center for Environmental Health Sciences The University of Montana Missoula, MT 59812 tony.ward@umontana.edu Phone: (406) 243-4092 Fax: (406) 243-2807 Abstract During the winters of 2006/2007 and 2007/2008, PM2.5 source apportionment programs were carried out within five western Montana valley communities. Filter samples were analyzed for mass and chemical composition, with this information utilized in a Chemical Mass Balance (CMB) computer model to apportion the sources of PM2.5. Results showed that wood smoke (likely residential woodstoves) was the major source of PM2.5 in each of the communities, contributing from 56% to 77% of the measured wintertime PM2.5. Results of 14C analyses showed that between 44% and 76% of the measured PM2.5 came from a new carbon (wood smoke source), confirming the results of the CMB modeling. In summary, the CMB model results, coupled with the 14C results, support that wood smoke is the major contributor to the overall PM2.5 mass in these rural, northern Rocky Mountain airsheds throughout the winter months.

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2009-A-302-ISES

Modeling Historical Exposure To Diesel Exhaust Particulate In The U.S. Trucking Industry

M. E. Davis,1 T. J. Smith,2 F. Laden,2 J. E. Hart,2 E. Garshick2; 1Tufts University, Medford, MA, 2Harvard University, Boston, MA

The Trucking Industry Particle Study (TrIPS) is a large-scale exposure assessment and epidemiology project focused on refining the shape of the dose response curve between diesel and other traffic exhaust exposures and lung cancer. The study has collected over 4,000 air pollution samples from various work locations (stationary and mobile sources) in and around trucking terminals across the US, as well as lung cancer outcomes and detailed work histories for 55,000 employees in this industry. An exposure model has been developed to estimate job-related exposures during the study period using structural equation modeling techniques. However, in order to build the dose-response model linking exposures with health outcomes, a cumulative exposure estimate must be derived for each member of the epidemiologic cohort. The historical extrapolation of exposures across locations and time periods not sampled presents a unique challenge because of the lack of data both spatially and temporally from which the estimates can be drawn. In this study, cumulative exposure estimates for each individual worker are generated using the underlying framework of the current exposure model, and then updated with data from an earlier study of the industry to control for changing work practices, as well as a historical panel of ambient monitoring data to control for changing background conditions over time. The results suggest significant differences in exposure levels across job groups, with the highest exposures observed during a period of diesel forklift use on terminal docks. Exposures were also elevated for drivers, and were highest for those making frequent stops within cities (as opposed to long distance hauls between cities). These exposure estimates are currently being linked with the individual work histories for each member of the epidemiologic cohort to estimate a dose response curve for diesel and lung cancer.

2009-A-362-ISES

Submicron Particles Exposure At A Bus Station And A Scooter Garage In Taipei, Taiwan

C. Chan, J. Shih, R. Shie; National Taiwan University, Taipei, Taiwan

Diesel-powered buses and gasoline-powered scooters are two important transportation tools in developing countries. Potential health risks may exist for people who are exposed to diesel and gasoline particles emitted from these vehicles. Bus stations and parking garages are two places where high concentrations of these particles may exist in most urban environment. We conducted this study to characterize number concentrations of

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submicron particles at a bus station and a scooter garage in Taipei, Taiwan. The Sequential Mobility Particle Sizer and Counter (SMPS+C, Grimm Model 5.403) was used to measure submicron particle number concentrations, temperature and humidity in these two locations. The count median diameters (CMD) of submicron particles in the bus station (20.6-22.6 nm) were smaller than those in the scooter garage (22.6-24.7 nm). The geometric standard deviations of submicron particles were 2.3 in the bus station and 2.16 in the scooter garage. Averaged total number concentrations of the aerosols with diameters from 11.1 to 1083.3 nm (NC11.1-1083.3) were 1.19×105 cm-3 and 1.02×105 cm-3 for bus station and scooter garage. There was significant diurnal variation in concentrations with four times difference at the bus station and 11 times difference at the scooter garage between rush hours and non-rush hours. There was positive correlation between NC11.1-1083.3 ( #/cm3) and traffic volumes (X, #/hr). The regression equations were: NC11.1-1083.3 =81631X+107537, R2=0.523 for the bus station and NC11.1-1083.3 =72982X+115262, R2=0.802 for the scooter garage. NC11.1-100.0 =7209.3X+577777, R2=0.533 for the bus station and NC11.1-100.0 =6558.3X+530332, R2=0.767 for the scooter garage. There was one peak concentration of submicron particles with NC11.1-12.1 being the highest among all particle sizes of NC11.1-1083.3, which were 70,100 cm-3 at the bus station and 90,641 cm-3 at the scooter garage. Our findings show that vehicular emissions are an important source of submicron particle exposures in Taipei.

2009-A-393-ISES

Contributions Of Take-off And Landing Activities Of Aircrafts To Ultrafine Particle Levels Near An Airport

H. Hsu,1 G. Adamkiewicz,1 C. J. Paciorek,1 J. Vallarino,1 S. J. Melly,1 J. D. Spengler,1 J. I. Levy,1 C. J. Karner,2 R. L. Wayson3; 1Harvard School of Public Health, Boston, MA, 2Wyle Laboratories, Inc., Arlington, VA, 3Volpe National Transportation Systems Center, Boston, MA

There is growing concern in communities surrounding airports regarding the contribution of various emission sources (such as aircraft and ground support equipment) to nearby concentrations, but isolating the contributions of airports is challenging. Within this study, we conducted extensive real-time monitoring with 1 minute resolution at four sampling sites surrounding T.F. Green Airport in Warwick, RI, in three one-week campaigns across different seasons in 2007 and 2008. Our objective was to determine the contribution of airport activities to concentrations of multiple pollutants, although the present analysis focuses on ultrafine particles and their relationship with flight activity and meteorology. Along with pollutant monitoring, high-resolution wind data were collected using sonic anemometers. Runway-specific Landing and Take-off (LTO) operation data were obtained from airport officials. As these data (time stamped to the nearest second) may have differential biases for large and small aircraft, we also collected noise measurements at 3 second resolution and explored using these data to pinpoint the departure and arrival time and as a source strength proxy. In our regression models, wind speed and direction were included as a nonparametric smooth spatial term using thin-

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plate splines applied to wind velocity vectors and fitted using linear mixed models. To better pinpoint the timing in the LTO cycle most contributing to elevated concentrations, and to capture the spatiotemporal complexity of our data, we used distributed lag models for flight activity. Results suggest significant positive associations between ultrafine particle concentrations and both departures and arrivals, with departures having larger effects. Generalized additive models for wind speed and direction suggest that the elevated ultrafine particle levels are associated with airport activities and local traffic sources, with a significant effect of wind direction only given high wind speeds. Our analysis allows for quantification of the marginal contribution of airport sources relative to other nearby sources.

2009-A-496-ISES

Seasonal Variability In Particulate Matter Concentration In Kathmandu Valley Between 2003-2007

J. Perodin, J. Hada, A. Sapkota; School of Public Health, College Park, MD

Epidemiological studies have shown that long-term exposures to elevated levels of ambient particulate matter (PM) are associated with various adverse health outcomes, including respiratory and cardiovascular diseases. However, most of the data regarding PM exposure and the associated health outcomes are from the developed countries. It is likely that the propensity of exposure to PM in the developing world may be significantly higher, given the lack of adequate regulations combined with the presence of additional sources of PM. We analyzed daily 24-hr average PM10 concentration data from six different air-monitoring stations across Kathmandu, Nepal that differed by industrial as well as traffic activities: Putalisadak, Patan, and Thamel (urban high traffic area); Kirtipur and Bakhtapur (urban background); and Matsyagaon (background area). The highest average annual concentrations of PM10 were observed in the urban high traffic areas with values ranging from 222 μg/m³ (Putalisadak) to 110 μg/m³ (Thamel). Similarly, the lowest annual average concentrations were observed for Matsyagaon (41 μg/m³) and Kirtipur (46 μg/m³). We observed significant variability in PM10 concentration across different seasons. Within each monitoring station, the highest concentrations of PM10 were observed during winter while the lowest concentrations were observed during the summer season. During the 5 year monitoring period, the PM10 air quality level at the three urban areas routinely exceeded the 24-hr US-EPA standard of 150 μg/m³. Putalisadak exceeded the 150 μg/m³ level 71% of time over the 5 year period while Patan and Thamel exceeded it 66 and 39 % of the time, respectively. Our results suggest that individuals living and/or working in the urban areas of Kathmandu valley are potentially exposed to very high levels of PM10. The extent of adverse health effects associated with such high exposures warrants further investigation.

2009-A-349-ISES

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Fate Of Libby Amphibole Fibers When Burning Contaminated Firewood

T. Ward; The University of Montana, Missoula, MT

Fate of Libby Amphibole Fibers When Burning Contaminated Firewood Tony J. Ward1*, Julie F. Hart2, Terry M. Spear2, and Brienne J. Meyer2 1Center for Environmental Health Sciences, The University of Montana, Missoula, Montana; 2Department of Safety, Health, and Industrial Hygiene, Montana Tech of The University of Montana, Butte, Montana. *Corresponding Author: Tony J. Ward Center for Environmental Health Sciences The University of Montana Missoula, MT 59812 tony.ward@umontana.edu Phone: (406) 243-4092 Fax: (406) 243-2807 Abstract In Libby, Montana, over 70 years of mining amphibole-contaminated vermiculite has led to amphibole contamination in areas surrounding the abandoned mine and in other areas throughout the town. In addition to contaminated soils, tree bark has also been found to be contaminated with amphibole fibers throughout the Libby area. As residential woodstoves are the main source of home heating in Libby, the purpose of this study was to determine if amphibole fibers become liberated into the ambient air when amphibole-contaminated firewood is combusted. Amphibole-contaminated firewood was combusted in new, EPA-certified stoves during three Trials. The results of these Trials showed that the majority of the fibers remained in the ash following the combustion process, suggesting that additional potential exposures can occur within the homes to those that clean the ash out of woodstoves. The Combustion Trials also revealed that amphibole fibers can become liberated into the ambient air during the combustion process. Amphibole fibers were found impacted in the ductwork, as well as detected in wipe samples collected from a tote used to concentrate the woodsmoke emissions. These findings stress the need for identifying a clean fuel source for the inhabitants of Libby to prevent future exposures.

2009-A-321-ISES

Vehicle Emissions In Congestion: Comparison Of Work Zone, Rush Hour And Free-flow Conditions

K. Zhang, S. Batterman; Environmental Health Sciences, University of Michigan, Ann Arbor, MI

Background and Objectives: Congestion in work zones, e.g., due to highway maintenance, accounts for 10% of the total congestion in the U.S. We know of no study

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that has measured or predicted emission rates in such zones. This study estimates vehicle emissions of light-duty cars and heavy-duty diesel trucks under work zone and rush hour congestion, and free flow (low traffic) conditions as a comparison case. Methods: Field experiments collected second-by-second vehicle speed profiles using GPS during three periods (7-9 am, 11 am-1 pm and 4-6 pm) on Tuesdays, Wednesdays and Thursdays in three consecutive weeks in fall 2008. The test vehicles were driven back and forth on a local I-94 segment in Ann Arbor, Michigan, following a defined protocol called the “car floating technique” which involved passing as many vehicles as passed the test vehicle. Separate speed profiles were obtained for cars and trucks. The smoothed speed profiles were inputted into the Comprehensive Emissions Model (CMEM) to generate second-by-second emissions for cars and trucks. Emissions and fuel consumption were expressed on a per-mile basis. Results: For cars, free flow conditions were associated with highest emission rates of CO, VOC and NOx, followed by rush hour congestion, and then work zone congestion. In contrast, work zone congestion consumed the most gasoline and produced the most CO2, followed by rush hour and free flow conditions. For trucks, work zone congestion was associated with the highest emissions of the four pollutants and fuel consumption, followed by rush hour congestion, and then free flow conditions. Conclusion: Emission rates depend on vehicle type, and the degree and type of congestion. While only three congestion case studies were analyzed, this study highlights the importance of congestion, and the findings are relevant to emission, exposure and health risk evaluations, as well as transportation planning.

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Symposium

R-SY101: Biomonitoring and CDC Environmental Public Health Tracking

A goal of the CDC Environmental Public Health Tracking Program (Tracking) is to expand and further utilize biomonitoring data to assess the extent and nature of human exposures to environmental toxicants to generate research and assessments to determine if causal linkages occur with adverse health outcomes. The Tracking Network provides a coordinated, integrated, standards-based web-based system for data integration and dissemination. The Tracking Network collects, integrates, analyzes and interprets data about environmental hazards, exposures, and associated health effects. The biomonitoring program is a natural data stream for Tracking and, in turn, Tracking provides valuable environmental and health outcome data for integration in the biomonitoring studies, allowing information to be placed in proper exposure context and used in health assessment evaluations. As a scientific approach biomonitoring increases the sensitivity and specificity of measures of human exposure to environmental chemicals/elements; identifies exposed populations; allows assessment of exposure mitigation efforts; and provides quality data for assessment of environmental hazards on human health. Biomonitoring involving Tracking support at the state and local levels has been effective for development of protocols, methods and exposure assessment; interstate collection/analysis cooperation; and often provided a cost-effective tool to determine exposure. Potential biomonitoring data sources include NHANES, data collected under CDC biomonitoring program, notifiable conditions registries, and chemical preparedness data collections. At the National level data on childhood blood lead levels are currently included on the National Tracking Network. Biomonitoring provides a direct method of measuring exposure, as opposed to indirect methods of estimating exposure that are used extensively in environmental health studies. Exposure markers integrate all routes and sources of exposure. Measurement of biomarkers provides an estimate of the actual dose of toxicant resulting from an environmental exposure. In order for an exposure marker to reliably measure an exposure and to be accurately interpreted, the toxicokinetics (i.e. rates of absorption, distribution, metabolism, elimination) and the mechanism and potency at the site of action of a toxicant must be understood. Biomonitoring or measurement of exposure markers increases the power of epidemiologic studies in identifying the associations between environmental exposure and disease. Biomonitoring is particularly needed to assess exposures where minimal environmental data exist or where multiple exposure routes exist such as from water, air, soil, consumer products, and complex food sources. Tracking states have some of the highest levels of arsenic and uranium in drinking water in the nation both from naturally occurring deposits as well as anthropogenic activities such as mining/milling and coal-fired power plants. Additional exposure issues identified by the needs assessments include the widespread use and concern over mercury and other metals, pesticides, and polycyclic aromatic hydrocarbons (PAHs) from wildfires and from urban and border diesel emissions. Endocrine disruptors, particularly phthalates and bisphenol-A, are also of concern and can be readily evaluated through biomonitoring of urine. Surveillance and targeted-population studies conducted

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in three Tracking states are presented in this session. Each was designed to identify and address environmental exposures of specific concern to state health departments and communities. CDC biomonitoring project results used in Tracking have included metals in urine, metals in blood spots, metals in blood, mercury in hair, and pesticides and phthalate metabolites in urine.

2009-P-588-ISES

Utah: The Use of Neonatal Blood Spots for Public Health Surveillance for Heavy Metal Exposure

S. LeFevre, S. Chaudhuri, W. Ball, S. Butala; Utah Department of Health, Salt Lake City, UT

Public health surveillance is a tool used to assess public health status, identify at-risk populations, define public health priorities, evaluate intervention programs and acquire and support research. The use of new born blood spots (NBS) have been recommended for conducting environmental health surveillance by the Utah Department of Health for fetal lead and mercury exposure using NBS. NBS samples submitted to the Utah Public Health Laboratory (UPHL) were analyzed for blood lead and blood mercury using paired blank and blood spots. Measurement of metal in extracts from the blank and blood spots were made utilizing an Elan DRC II ICP-MS. During 2007, 3,579 (6.5%) samples randomly drawn from NBS submitted to the UPHL for the 54,943 live births in Utah were analyzed. In 1991, the Centers for Disease Control and Prevention (CDC) set the definition for an elevated child blood lead level to ≥ 10 ug/dL. The EPA uses 5.8 ug/L as the surveillance threshold for blood mercury. The state rate for elevated mercury results was 12.96 cases per 1,000 births (45 / 3,471; 95% confidence interval (CI) = 12.84 - 13.08). If this rate accurately reflects the real incidence of children born with elevated mercury levels, then one could anticipate 712 (95% CI = 706 - 719) children were born in 2007 with elevated blood mercury levels. For lead, the state rate for elevated results was 4.70 cases per 1,000 births (15 / 3,192; 95% CI = 4.62 - 4.77). This rate suggests that 258 children (95% CI = 254 - 262) were born in Utah in 2007 with elevated blood lead levels. No correlation was found between a geometric mean blood lead and blood mercury (Pearson’s Correlation Coefficient (PCC) = 0.04, p < 0.02). No infants were found to have concurrent elevated blood lead and blood mercury. A weak inverse correlation of birth weight in males to the newborn’s blood lead level was observed. Using blood spot data to predict and respond to population with increased risk to childhood developmental problems is one example of the utility of using these data for public health action. One utility of these data is developing understanding and intervention for autism spectrum disorder (ASD). Utah has the third highest prevalence of ASD among fourteen states with surveillance programs for this disease and the highest prevalence for male children. The prevalence of ASD in Utah among children age eight years was 7.5 per 1,000 children (aged 8 years) in 2002. Using this rate, 400 children

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from the 2007 birth cohort are expected to diagnosed with autism by age 8 years. In addition to the newborns, these results identify mothers with potentially elevated levels of these metals. Both lead and mercury have been shown to contribute to a number of degenerative health outcomes in adults to include behavioral and personality changes, encephalopathy, memory loss, dementia, peripheral nerve damage, and organic damage. Maternal body burden of both lead and mercury are controllable by nutrition, other healthy life choices and other medical interventions. Since public health interventions are available, surveillance for and identification of at-risk populations is warranted.

2009-P-589-ISES

Maine: The Use of Residual De-identified Blood Lead Specimens for Public Health Surveillance of Metals in Children

A. E. Smith, D. Rice, S. Xing, J. Martha; Maine Department of Health and Human Services, Augusta, ME

Maine has conducted a feasibility study of tracking levels of metals in children’s blood. The study was a joint project involving the Maine Environmental Public Health Tracking (ME-EPHT) Program and the state Health and Environmental Laboratory (HETL). Approximately 1400 residual venous blood specimens from children age 1 to 5 years submitted for lead analysis were de-identified, re-labeled and separately analyzed on an ICP/MS for multiple metals (mercury - Hg, cadmium- Cd, arsenic- As, uranium - U, manganese - Mn, antimony - Sb, tin - Sn, and selenium - Se) using a modified CDC method for measuring lead, cadmium and mercury in blood. Sufficient demographics were retained so data could be stratified by gender, year of age, region of the State, and season. Some metals were frequently detected in 90 % or more of blood samples (As, Mn, Se, Sb), others were detected in less than 10% samples (Cd and Sn). Hg and U were detected in 60% and 30% of samples, respectively. Percentile values of Cd and Hg were similar to those reported in the National Biomonitoring Study for children. Spearman rank correlations between metals revealed significant correlations between Se and the other metals As, Mn, Se and Hg. As levels were additionally correlated with Hg, and Sb was correlated with U. There was a tendency for As, Hg and Se levels to increase with year of age, whereas levels of Sb decreased with year of age. There was evidence for both regional and seasonal differences in Sb levels. This pilot demonstrates that it is feasible to operate an ongoing biomonitoring program involving the analysis of more than 1000 samples per year.

2009-P-590-ISES

New Mexico: Biomonitoring of Phthalate Metabolites in Urine

L. Flowers, D. Mills; New Mexico Department of Health Scientific Laboratory Division, Albuquerque, NM

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The Rocky Mountain Biomonitoring Consortium (RMBC) was formed with CDC biomonitoring grant funds to apply regional resources to address environmental public health concerns in the states of Arizona, Colorado, Montana, New Mexico, Utah, and Wyoming. The goal of the RMBC is to implement and expand a regional laboratory-based biomonitoring program to assess the magnitude and extent of human exposures to environmental toxicants. The interpretation of biomonitoring results has been conducted in collaboration with New Mexico and Utah CDC Environmental Health Tracking Programs. The RMBC states share common demographic, geophysical and environmental characteristics, and have extensive histories of mining, agriculture, and Federal military operations. The RMBC states have some of the highest levels of arsenic and uranium in drinking water in the nation. Additional exposure issues include the widespread use and concern over pesticides, perchlorate in groundwater, PAHs in air from wildfires and from diesel emissions. Endocrine disruptors are also of concern and began to be addressed by analysis of phthalate metabolites in urine for more than 200 samples. Phthalates are industrial compounds widely used in industry for a variety of products including detergents, children’s toys, food packaging, medical products, and also in personal care products such as shampoo, soaps, hair spray, and nail polish. Human exposure occurs primarily through direct contact with these sources. Health effects associated with phthalates include decreased sperm production, dysmorphology of male genitalia, and intersex development including feminization of male fish, amphibians, and gulls. The phthalate metabolites that were measured using LC/MS/MS include monomethyl phthalate (metabolite of dimethylphthalate), monoethyl phthalate (metabolite of diethylphthalate), mono-n-butyl phthalate (metabolite of dibutyl phthalate), monobenzyl phthalate (metabolite of benzylbutyl phthalate). In addition, the consortium measures mono-(2-ethyl-5-hydroxyhexyl) phthalate (metabolite of Bis-2-ethylhexyl phthalate), which is the only phthalate in drinking water that is regulated by the EPA. The results of the urine analyses for phthalate metabolites and the potential source and health implications and additional data needs will be presented and discussed.

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Symposium

R-SY102: Community Engagement to Facilitate Exposure Assessment and Environmental Health Research

The National Institute of Environmental Health Sciences (NIEHS) has established a new integrated, unified program called Partnerships for Environmental Public Health (PEPH) to coordinate the Institute’s extramural activities in environmental public health. The PEPH program is an umbrella program that brings together scientists, community members, educators, health care providers, public health officials, and policy makers in the shared goal of advancing the impact of environmental public health research at local, regional, and national levels. A major focus of the PEPH program is to encourage community participation in the research process, from development of research questions through translating and disseminating research findings. Community participation can enhance research in many ways. Benefits include improved recruitment and retention of study participants; community input to help inform the science and/or refine the research focus of the project; increased access to the multiple exposure environments experienced by vulnerable populations (home, work, and school); use of community members to help collect exposure data; and more effective translation and dissemination of research findings. This symposium will explore some of the opportunities and benefits of community participation by highlighting success stories from several NIEHS-sponsored research programs within the PEPH umbrella program. Moderator: Caroline Dilworth, PhD, NIEHS. Presentation #1: Community participation in the Breast Cancer and the Environment Research Centers (BCERC): Perfluorooctanoic acid (PFOA) and Pubertal Maturation in Young Girls (Susan Pinney, PhD, University of Cincinnati) - This presentation will highlight the use of community volunteers to assist with participant recruitment and retention. It will also describe the important role that community outreach and translation can play in developing a research dissemination and risk communication plan when study participants are found to have high exposure to know or suspected toxins. Presentation #2: Community participation in Environmental Justice Research (Thomas Arcury, PhD, Wake Forest University) - This presentation will highlight the importance of community-based research approaches when research is focused on improving the health of rural and minority populations. Presentation #3: Community Participation in research implementation, hypothesis generation and interpretation of study findings (Victoria Persky, MD, University of Illinois at Chicago) - This presentation will describe the evolution of an academic-community partnership in their collective efforts to address the myriad of environmental concerns affecting disadvantaged communities in Chicago and highlight the importance of community involvement in all phases of environmental health research, from development of research questions through translating and disseminating research findings. Presentation #4: Vision of the NIEHS Partnerships for Environmental Public Health Program (Gwen Collman, PhD, NIEHS) - Dr. Collman is the Interim Director of the Division of Extramural Research and Training (DERT) at NIEHS. This presentation will address the role of the NIEHS in fostering coordination between researchers and community partners

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in exposure science research, as well as outline the Institute’s broader vision for environmental public health research.

2009-P-207-ISES

Community Participation in the Breast Cancer and the Environment Research Centers (BCERC): Perfluorooctanoic Acid (PFOA) and Pubertal Maturation in Young Girls

S. M. Pinney; University of Cincinnati College of Medicine, Cincinnati, OH

Background: Earlier pubertal maturation is related to increased risk of breast cancer. Certain environmental chemicals can act promote estrogenic activity, which may lead to earlier breast development. Methods: Within the NIH Breast Cancer and the Environment Research Centers (BCERC), we conducted a study of multiple environmental biomarkers, including PFOA and other PFCs in serum of young girls (age 6-7 years at entry) from two sites. At the greater Cincinnati site (N=379 girls), community volunteers were active members of the research team, assisting with various measures to promote recruitment and retention. Pubertal staging was conducted by clinicians or trained research staff, every six months, for as long as four years. Upon the discovery that some study participants had high levels of one compound, the entire study team implemented an information dissemination and risk communication plan. Results: Detectable serum levels of PFOA were found in all but one of the 337 serum samples. The median was 7.5 ng/ml (range < LOD 0.01 to 55.9 ng/ml), somewhat higher than the median for children 12-19 years age in the NHANES 2003-2004 population (3.9 ng/ml). Only 62.6% of our study participants had serum concentration values below the NHANES population 95th percentile value (8.6 ng/ml), and 64 girls (19.0%) had values > 11.3 ng/ml. Girls with higher serum concentrations seemed to be clustered in one residential area. Length of residence and being breast fed by a mother living in that area was related to higher concentrations. Over a one year period, average levels decreased by about 20%. Information about the chemical compound and the finding was communicated to the families and community through meetings and written materials. Conclusions: Information needs of study families seem to have been met. Sharing of information with community public health agencies has fostered further bi-directional information sharing with the research team.

2009-P-208-ISES

Community Participation in Environmental Justice Research

T. A. Arcury; Wake Forest University School of Medicine, Winston-Salem, NC

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Rural and minority communities often experience considerable exposure to environmental hazards that can affect their health. Members of these communities have little financial or political power to gain redress from these exposures, and experience significant environmental injustice. Pubic health research with these vulnerable populations is needed to document their exposures and health outcomes, and to implement needed interventions. However, this research is often difficult to implement. Such communities can be characterized as hidden or hard-to-research populations for public health research in that no sampling frame exists for the population, so its size and boundaries are not known, and the members of the population have strong privacy concerns due to a history of discrimination. Community-based participatory research (CBPR) provides a framework for conducting basic and translational environmental health research in rural and minority communities. Our CBPR model is proactive in developing active participation form all community segments. It allows community members to use the modes of participation in which they are comfortable within three research domains: consultation, strategic planning, and implementation. CBPR also provides a framework for translational research to improve community health and to address policy change. The results of CBPR can be translated along four policy related paths: (1) reporting personal exposures to study participants; (2) developing education programs that address the exposures and health of the entire community; (3) improving the knowledge and practice of clinicians serving the community; and (4) improving policy and regulations. This presentation describes the CBPR models of basic and translational research. The models are illustrated with examples from our CBPR research with immigrant farmworker and immigrant poultry processing worker communities.

2009-P-209-ISES

Community Participation in Research Implementation, Hypothesis Generation and Interpretation of Study Findings

V. W. Persky; University of Illinois at Chicago School of Public Health, Chicago, IL

Community involvement in environmental epidemiology and exposure assessment is key, not only for implementation of projects, but also for hypothesis generation and interpretation of findings. This presentation will describe the evolution of our group’s activities on the Southside of Chicago. It will described the process by which our community health educator program was extended from the Westside of the city, the collaborations that ensued, hypotheses developed to address issues in public housing, intervention strategies, subsequent funded grant proposals and public health interventions. Each step of the process was initiated by community concerns for environmental exposures, initially related to housing conditions, then from demolitions of high rise public housing, subsequently from reconstruction of the Dan Ryan Expressway and low rise demolitions, and, more recently, stemming from sites used for transit equipment. Important in defining the issues and initiating effective intervention strategies was the sustained involvement of academic partners with community residents, as well as representatives of a wide variety of public and non-profit agencies.

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2009-P-206-ISES

Vision of the NIEHS Partnerships for Environmental Public Health Program

G. Collman; NIH\NIEHS, Research Triangle Park, NC

The Partnerships for Environmental Public Health (PEPH) program is an umbrella program designed to coordinate and support both ongoing and future environmental public health research activities supported by the Division of Extramural Research and Training at NIEHS. For the purposes of this program, Environmental Public Health is defined as the science of conducting and translating research into action to address environmental exposures and health risks of concern to the public. The PEPH program emphasizes robust research to investigate linkages between exposure and disease, as well as research to improve the theories, methods, and implementation strategies for working with communities to address their environmental health concerns and communicating health risks. This presentation will outline the Institute’s broader vision for the PEPH program as well as address the role of the NIEHS in fostering coordination between researchers and community partners in exposure science research.

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Symposium

R-SY103: Emerging Methods for Comprehensive Measurement of Personal Exposures: Discussion of Emerging Issues in Applying Measures for Exposure, Diet, Physical Activity, Stress and Biological Response in the NIH Genes, Environment, and Health Initiative

The US Department of Health and Human Services and the National Institutes of Health established the NIH Genes, Environment and Health Initiative in 2006 to lay a foundation for future studies in the interaction between Genetic and Environmental factors in human disease. An initial effort of this program has been the establishment of improved techniques for measuring personal exposures including chemical exposures, diet, physical activity, psychosocial stress and drug abuse as well as biomarkers of the initial biological response to those factors. These measures are intended to give a more comprehensive view of exposure including information on multiple analytes as well as temporal and spatial variability in exposures. An additional primary focus is on the development of measures that are minimally obtrusive – which require little to no participant burden or minimally invasive monitoring of biomarkers. An intermediate goal of the program is to integrate measures of exposure to change the perspective of exposure from being a single event to an integrated continuum. It is expected that, for instance, simultaneous measurement of PM and Ozone exposure in conjunction with detailed analysis of physical activity could add information about the correlation between exposure and increased activity, potentially signaling an increased risk of asthmatic events in susceptible populations. This expanded demonstration session will feature an overview presentation of the Exposure Biology Program, rapid overviews (1 minute/1 slide presentation) by EBP grantees and hands-on demonstrations of prototypic tools being developed by several of the program’s grantees. These will include a variety of new measures for each of the emphases of the Exposure biology program.

2009-P-176-ISES

Improving Dietary Assessment Methods Using the Mobile Phone and Digital Imaging

C. Boushey; Purdue University, West Lafayette, IN

Nutritional epidemiology is concerned with quantifying dietary exposures and their association with disease risk. Diet represents one of the most universal biological exposures; however accurate assessment of food and beverage intakes is problematic. We are developing a novel food record method using a mobile device that will provide an accurate account of daily food and nutrient intake. This system will generate an accurate account of daily food and nutrient intake among adolescents and adults. The mobile

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computing device provides a unique vehicle for collecting dietary information that reduces burden on record keepers. Our approach includes the use of image analysis tools for identification and quantification of food consumption. Images obtained before and after food is consumed can be used to estimate the diet of an individual. Image classification accuracy under good lighting conditions has achieved a 70.68% accuracy compared to 34.91% under bad lighting conditions and 93.75% for replica foods. To aid with interaction design, a total of 70 adolescents ages 11-18 y and 57 adults ages 21-65 y were recruited to participate in one or two meal sessions. Prior to their first meal, participants were instructed to capture an image with the mobile telephone food record (mpFR) that included all foods and beverages, and the fiducial marker (an item of known size), before and after eating. If these items were not visible, volunteers were instructed to retake images until a useful image was captured. After using the mpFR, the proportions of adults agreeing that it would be easy to take images before meals and after meals were significantly higher than adolescents (83% vs. 37% P<.0001 and 74% vs. 41% vs. P<.0001, respectively). Collectively, these results reinforce the importance of using evidence-based development to improve exposure biology methods.

2009-P-177-ISES

Mobile Food Intake Visualization and Voice Recognizer (FIVR) Automatic Food Volume Estimation Through 3D Images Captured via a Mobile Phone

R. Weiss; Viocare, Princeton, NJ

Assessing nutrition in population-based studies requires accurate tools for capturing food intake that can be compared to parameters such as cancer, obesity and coronary heart disease. Many methods of dietary assessment have been described; no method adequately assesses intake of free-living individuals. We are developing a simplified process for individuals and at the same time improving accuracy of portion estimation using mobile phones. The overall purpose of our study is to design techniques for automatically identifying food types and volume from photographs taken with a phone. A phone will enable subjects using the camera, speech recognition and probing questions to automatically and accurately record their intake. This can add visual data to a verbal record, query for details at the time of consumption and help to interpret the image. The device will transmit verbal and visual data and a querying system will capture details about the foods while the data is current. The final application will include image definition, color analysis and texture classification that will facilitate the food identification process. While most people can readily state what it is they are eating, it is generally much more difficult to estimate the portion size than the food identity. The portion estimation problem can be handled using computer vision techniques. Our system uses a “plate finder” to localize the recognition space, performs segmentation (determining where one food begins and the other ends) and collects three images taken from different angles to compute the 3D structure of each food. The tool utilizes texture, color, and shape to segment the 3D image according to local-area similarities and define individual foods. The 3D model of food items are measured against a known fiducial

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marker to determine a volume for each food which can then be converted to a weight. Before and after eating images determine amount eaten thus facilitating a detailed dietary analysis.

2009-P-178-ISES

Wearable Ultra-fine Particulate Matter (PM) Sensor for Childhood Allergy and Air Pollution Study

S. Son; University of Cincinnati, Cincinnati, OH

A Nano/Microtechnology-based PM sensor system has been being developed for childhood allergy and air pollution study under the support of NIEHS. The advance of sensor is creating an opportunity for epidemiologist to collect real-time data of position- tagged ultra-fine PM number concentration. The current development has the sensor measure environmental PM number concentration in the size range of 10 – 1000 nm (PM1.0) with one-second temporal and one-meter spatial resolutions. Furthermore, the PM1.0 sensor has high mobility which is an essential feature of wearable devices. Current sensor has ? 3-gravitational-acceleration mobility where sensor can reliably collect the data during children’s walking and running. The targeting sensor mobility is ? 5-gravitational-acceleration that can be under a variety of rugged children’s activities including jumping, playing at playground, and possibly playing sports. For the development of wearable PM1.0 sensor, nano/micro technologies have been employed in addition to conventional Condensate Particle Counting principle. The implemented nano/micro technologies are including Micro Thermofluidics, Nanomaterial, and MEMS (Micro-Electro-Mechanical-System) sensor & actuator. This presentation will provide recent advances on development of wearable PM1.0 sensor based on nano/microtechnologies.

2009-P-179-ISES

Personal Monitoring Of Black Carbon With Newly Developed Miniaturized Samplers

S. Chillrud; Columbia University, Palisades, NY

Epidemiology studies addressing air pollution health effects are increasingly concerned with the impacts of local sources like traffic on health outcomes under study. It is now widely recognized that fixed, central site monitoring systems will generally be uninformative for testing intra-urban exposure/response hypotheses. Ongoing efforts to improve personal monitors for exposure and epidemiological health studies via miniaturization of sensors and development of smart sensor platforms are critical for filling this gap. Here we report on efforts for developing and validating miniaturized personal monitor platforms for black carbon (BC). Data from two different monitors will

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be presented including a 3-location smart sampler, with location and compliance sensors, and the newly available Magee micro-aethalometer which provides real-time measurements of BC. Results will be presented for basic validation of the functionality of the monitors as well as preliminary exposure results from an ongoing study of acute airway response (measured by spirometry, exhaled NO and inflammatory mediators in exhaled breath condensate) to BC exposures for 9 and 10 year old children from Northern Manhattan and the South Bronx. Data from a 3-axis accelerometer clearly shows when the monitors are being worn or not. Different approaches are being tried for overcoming the challenges of using GPS in urban areas, ranging from using more sensitive chipsets and developing power saving algorithms in integrated units to adding external battery packs to commercial GPS data loggers. Side by side comparisons of two to six Magee micro-aethalometers co-located on a person or out of a window indicates excellent sensitivity and stability with a mean RSD across the multiple units of 9%. Preliminary tests also indicated that BC readings of the micro-aethalometer is impacted by relative humidity, an issue to be overcome by drying the airflow before the filter.

2009-P-180-ISES

Utilizing 3-Axis Accelerometry to Predict Respiration Rate for Adult Using the RTI MicroPEM™ PM Exposure Monitoring Platform

C. Rodes; Research Triangle Institute, RTP, NC

The personal version of the RTI MicroPEM™ platform initially include a single axis accelerometer chip to provide movement data that could be quantified as to the level of protocol wearing compliance. These data have been shown to be especially important for general population exposure studies where poor wearing compliance has been observed, resulting in exposure misclassification bias. Research funding provided by a 4-year NIEHS grant (U01ES016093) has allowed a much more sophisticated and sensitive (0-2g range) 3-axis accelerometer chip to replace the simplistic single axis sensor. This upgraded accelerometer now provides the capability to determine protocol compliance, as well as provide x, y, and z-axis sensing that can be more robustly related to the motion levels of adults during typical daily activities. To accomplish this first required significant reprogramming to provide optimal data collection rates. Scripted and controlled activities were then conducted with the MicroPEM™ worn in the breathing zone and the ventilation rate of the test subject researcher simultaneously monitored (OxyCon VE) and compared with similar "bare" MIT MITes accelerometers worn at strategic body locations. Regression fits were then made between various combinations of accelerometer output (single channel, vector sum, composite change) and ventilation rate (liters/min) for each activity range to determine whether significant and predictable associations were observed. Encouraging preliminary data will be presented showing that (for example) a Pearson correlation of 0.72 was observed between accelerometer output during treadmill controlled walking speeds up to 5 mph and observed ventilation rate. The wearing tightness of the personal exposure monitor was found to be an important

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contributing variable, with the correlation weaker when the sensor was not sufficiently tight.

2009-A-284-ISES

Label-free Biosensors With Low Cost Biochips For Detection Of Chemical And Biological Agents

P. Nikitin,1 B. Gorshkov,1 T. Ksenevich,1 M. Nikitin,1 T. Brusentsova,1 M. Nunuparov,1 E. Baranova,2 S. Biketov2; 1General Physics Institute, Russian Academy of Sciences, Moscow, Russian Federation, 2State Research Center for Applied Microbiology and Biotechnology, Obolensk, Moscow Region, Russian Federation

Several types of label-free biosensors are extensively investigated for environmental monitoring and bio- and chemical agent detection. Still a lot of efforts should be dedicated toward increasing of their sensitivity, design of multi-channel robust systems, decreasing of the biochip cost. For these purposes, new biosensing methods have been developed based on measuring receptor-ligand thickness and employment of microscope glass slips as biochips without deposition of any metal or dielectric films. Label-free biosensor “Picoscope™” has been developed for fast real-time detection of pathogens, pathogen products, chemical and biological warfare agents. For the device testing, monoclonal antibodies (MAb) were produced to serve as biological recognition elements for detection of anthrax spores (B. anthracis) and insecticide pyrethroids in liquid samples. The carefully selected target antigens have allowed us to generate MAb of necessary specificity and sensitivity. The first target-glycoprotein antigen from B. anthracis exosporium has been extracted. Another target (main pyrethroid metabolite) was produced by synthesis of hapten -3-phenoxybenzoic acid (PBA) followed by hapten conjugation with carrier proteins. Both antigens were used as immunogens for hybridoma generation, which produced MAb that reacted specifically with the spores of various B. anthracis strains and with the conjugate of PBA with BSA. The detection limit for B. anthracis spores in label-free mode was estimated to be 2×106 cfu/ml. Real-time pyrethroid detection in a competitive immunoassay has been tested using anti -PBA MAb and immobilized PBA conjugate. Besides, in our experiments magnetic nanoparticles were used for amplification of the Picoscope™ response, for antigen pre-enrichment, for active acceleration of immunoreagents’ binding, and for realization of "magnetic washing" by magnetic field gradients. The described approaches can be used to generate MAb to a desired target. The developed biosensors can be used for detection of biological and chemical threat agents.

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Symposium

R-SY104: Biomarkers and Other Measures of Exposure as Tools to Evaluate Exposure of Humans to Pathogens

A 90 minute symposium describing how biomarkers and other measures of exposure have been used to determine human exposure to microbial pathogens Abstract: There is a growing interest in exposure patterns related to microbial pathogens in water environments. Traditionally, exposure has been defined by the occurrence of pathogens in water and the belief that contact alone constitutes exposure. This belief carries with it a great deal of uncertainty because it is not actually known if a pathogen has breeched a body’s defense barrier and invaded the body where it may cause infection or disease. The use of biomarkers of exposure, which signal infection by a pathogen, is reducing this uncertainty associated with exposure. Biomarkers of exposure related to the humoral and cellular immune systems are being analyzed in saliva specimens, Saliva specimens can be obtained without using invasive techniques, and this greatly facilitates examining large study populations, including children. This session will address an intervention study which examined a drinking water exposed population for evidence of lower infection rates after significant improvements to the water treatment process in a plant serving the study population. Infection rates were measured before and after the intervention using saliva specimens, which were examined for evidence of infection using antibodies to Cryptosporidium, Norovirus, Rotavirus, Helicobacter and Toxoplasma. The session also includes research where epidemiological data and biomarker data will be collected during prospective epidemiology studies to determine how well these data relate to each other in swimmers exposed to bathing waters of varying quality. Other research that describes health studies involving cytokine biomarkers of exposure to mycobacteria and biomonitoring surveys will be addressed.

2009-P-232-ISES

Salivary Antibody Responses as an Indicator of Waterborne Infections: Pilot Community Study Before and After Installation of UV Treatment

A. Egorov,1 T. Wade,2 S. Griffin,3 G. S. Fout3; 1U.S. EPA, National Center for Environmental Assessment, Cincinnati, OH, 2U.S. EPA, National Health and Environmental Effects Research Laboratory, Chapel Hill, NC, 3U.S. EPA, National Exposure Research Laboratory, Cincinnati, OH

This ongoing project involves the development, validation and pilot application of a multiplex immunoassay based on Luminex microsphere technology to measure salivary antibody responses to the potentially-waterborne pathogens, noroviruses (Norwalk, VA387 and VA207), rotaviruses, Cryptosporidium, H. pylori and T. gondii. This salivary

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immunoassay has been validated for the detection of prevalent chronic infections, H. pylori and T. gondii, using diagnostic ELISA tests of paired serum samples. Validation of immunoconversion tests for the detection of incident acute infections involved an analysis of prospectively collected saliva samples from a Norwalk virus challenge study. These samples were tested repeatedly using various sample pre-treatment methods and assay buffers. Different immunoconversion definitions based on the ratio of antibody responses to the recombinant viral protein and internal cross-reactivity control, and the ratio of specific and total antibody concentrations were also evaluated in order to optimize the specificity and sensitivity of the assay. An optimized immunoconversion test is currently being applied in the ongoing analysis of saliva samples from a prospective pilot epidemiological study of waterborne infections. This study included two cohorts, before and after the introduction of UV treatment, in a community that used microbiologically-contaminated river as its source of drinking water. A total of more than 10,000 monthly saliva samples were collected from nearly 3,000 individuals participating in the two study cohorts. Preliminary results show that more than 10% of individuals with diarrhea or vomiting during follow-up had immunoconverted to noroviruses. This analysis is expected to be completed in 2010. Further development of the salivary antibody method will involve expansion of this multiplex assay to include more waterborne pathogens and more assay validation efforts.

2009-P-233-ISES

Assessment of Exposures to Fecally-contaminated Recreational Water

T. J. Wade,1 A. P. Dufor,2 E. Sams1; 1U.S. EPA, Research Triangle Park, NC, 2U.S. EPA, Cincinnati, OH

Exposure to fecally-contaminated recreational waters can pose a health risk to swimmers and other recreators. Since 2003, we have interviewed nearly 27,000 respondents at seven beaches impacted by treated sewage discharge. Information was collected about the duration and exposure to water, including whether water was swallowed. This analysis summarizes and quantifies these and other exposures (such as contact with sand and algae) especially with regard to available demographic characteristics. Across the seven beaches, 9% of respondents reported swallowing water. Young children were much more likely to report swallowing water. Twenty-five percent of those 5 years of age and under and 26% of those 6 to 10 years of age reporting swallowing water, compared to only 2% of those over 55, 4% of those 20-55 years of age, and 9% of those 10-19 years of age. Males were also more likely to swallow water (11%) than females (7%). Fewer Asian and white respondents reported swallowing water (6% and 8%, respectively) than African American (12%), Hispanic (12%), and multi-ethnic (18%) respondents. Among those who reported contact with water, the average time in the water was 56 minutes, with those 6-10 years of age reporting the longest mean contact time of 87 minutes. Males also reported spending longer in the water on average (61 minutes) than females (52 minutes). These results indicate that an extended duration of exposure to water and swallowing

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water are both prevalent, particularly among children. Differences in exposure gradient are also evident by race and sex. These results can provide insight into potentially susceptible populations and can inform quantitative risk assessments.

2009-P-234-ISES

Low Dose Exposure, Protective Immunity and the Negative Benefits of Improved Treatment

F. Frost,1 K. Tollestrup,2 T. Kunde3; 1Aurora Health Care, Milwaukee, WI, 2Dept. of Family and Community Medicine, University of New Mexico, Albuquerque, NM, 3New Mexico Public Health Laboratory, University of New Mexico, Albuquerque, NM

It has long been suspected that endemic waterborne illness, not associated with outbreaks, occurs commonly but is rarely detected (Frost et al. 1996). Our studies examined whether the occurrence of acute gastrointestinal illnesses declined after filtration and ozonation were added to a previous unfiltered but chlorinated high-quality surface water source and whether serological evidence of prior infection to Cryptosporidium was related to a reduced occurrence of enteric illness. Two cohorts living in the same city participated in the study. The first was served by water with this enhanced water treatment, and the second was served by unfiltered, chlorinated surface water. Daily illness diaries prior to (phase1) and after (phase 2) initiation of water filtration/ozonation were collected from both cohorts. To assess the risk of Cryptosporidium infections, we collected sera from a sample of each cohort. We compared illness diaries for people with a strong baseline serological response to Cryptosporidium antigens to those without. Following the intervention, residents reporting 3+ illness episodes in phase I reported an unanticipated, highly significant 4- to 5-fold increased risk of illness during phase II. However, people from either group with a strong baseline serological response were at a reduced risk of gastrointestinal illness during phase 2. These data suggest illness risks differ by whether the person had a strong serological response to Cryptosporidium antigens. People at the highest illness risk during the baseline period may be negatively affected by improved water treatment. If confirmed, these data suggest improved water treatment that removes or inactivates low doses of waterborne pathogens may negatively affect people at highest risk of waterborne disease.

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Interactive Poster

R-IP101: Exposure Science for Prioritizing and Evaluating Chemicals

2009-A-325-ISES

Identification Of Environmentally Relevant Mixtures To Aid In Multiple Chemical Risk Assessment

R. Tornero-Velez, P. Egeghy, N. Tulve, D. Stout, C. Dary; U.S. Environmental Protection Agency, Research Triangle Park, NC

A challenge with multiple chemical risk assessment is the need to consider the joint behavior of the mixture. Often these evaluations are relevant only for the set of compounds that may act by a common mechanism of action. For a set of N compounds, the possible number of binary pharmacological or pharmacokinetic interactions is N(N-1)/2. Therefore, the scope of toxicological evaluations becomes daunting as N increases, and this does not yet consider the number of possible higher-order interactions. However, economic factors control the co-occurrence of mixtures in the environment, meaning that the observed set of combinations is less than the theoretical set since many chemicals are unlikely to occur together in time and space. The implications are that information on possible or probable environmental mixtures can help inform toxicological evaluations early in the risk assessment process to pair down the numbers of testable combinations. In this study, we applied methodology developed in the field of community ecology to examine observed combinations of pyrethroid insecticides from two national surveys. The application of biogeographical methods is discussed, including consideration for development of presence/absence matrices for environmental wipe sample data, and choice of null model analysis which specifies the underlying structure of the data. Results indicate that the number of stable and significant numbers (tested at α=0.05) of environmental combinations is relatively small, suggesting that this methodology provides a promising avenue for informing the risk assessment of chemical mixtures.

2009-A-367-ISES

Development Of A Decision Scheme To Evaluate Chemical Exposure Information Requirements Under REACH

Y. Bruinen de Bruin, T. Aldenberg, A. Hollander, T. Vermeire; RIVM - National Institute of Public Health and the Environment, Bilthoven, Netherlands

Under REACH, Integrated Testing Strategies (ITS) need to be developed to increase the use of non-testing information for regulatory decision making of chemicals. Exposure is a decision element in ITS on which testing decisions are based. Exposure informed testing

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includes both Exposure Based Waiving (EBW) and Exposure Based Triggering (EBT). The principle behind any EBW is that there are situations when human or environmental exposures are so low that there is a very low probability that the acquisition of additional effect information may lead to an improvement in the ability to manage risk. In contrast, EBT refers to situations where human or environmental exposures are considered high enough to justify testing above the regulatory requirements. The justification for EBW/EBT can be either qualitative or quantitative. Qualitative justification for EBW could be based on specific use, conditions, or limited emissions. If absence of exposure cannot be justified qualitatively, a quantitative exposure assessment may be needed using REACH exposure scenarios and risk characterization based on hazard and exposure. The latter, should demonstrate that exposure is below a ‘no further action level’, such as PNECs (Predicted No-Effect Concentrations) or TTCs (Thresholds of Toxicological Concern).This presentation will discuss a proposed decision scheme to evaluate the validity of the methods and reliability of the results used as environmental exposure information to justify EBW/EBT. Further evaluation should give insight in the necessary improvements and criteria to make the EBW/EBT concept feasible. Acknowledgements: This presentation is supported by the EU Sixth Framework project OSIRIS (Optimized Strategies for Risk Assessment of Industrial Chemicals through Integration of Non-Test and Test Information). Special thanks to the sponsors, being the European Commission, the Dutch Ministry of Housing, Spatial Planning and the Environment, the Dutch Ministry of Social Affairs and Employment, and RIVM and to all contributing colleagues of TNO and RIVM.

2009-A-508-ISES

Development Of A Tiered Set Of Modelling Tools For Derivation Of Biomonitoring Guidance Values

M. Bartels,1 G. Loizou,2 P. Price,1 M. Spendiff,2 S. Arnold,1 J. Cocker,2 N. Ball3; 1The Dow Chemical Company, Midland, MI, 2Mathematical Sciences Unit, Health Improvement Group, Health and Safety Laboratory, Buxton, United Kingdom, 3Dow Europe GmbH, Horgan, Switzerland

There are numerous programs ongoing to evaluate environmental exposure of humans to xenobiotic chemicals (eg: EU ESBIO; US CDC NHANES; Canadian Health Measures Survey). The goal of these projects is to determine relative trends in exposure to chemicals, across time and subpopulations. Due to the lack of data, there is little information correlating biomarker levels with exposure concentrations, and as a result, difficulty in utilizing biomonitoring data for biological guidance values. A suite of model tools would be the most appropriate method to facilitate forward- and reverse-dosimetry estimations of xenobiotic exposure to aid in interpretation of biomonitoring results. A tiered approach of simple, arithmetic pharmacokinetic (PK) models, as well as more standardized PBPK models, would promote the use of human biomonitoring data in the development of appropriate biomonitoring guidance values (BGVs). The output of these evaluations will be potentially useful in setting hazard/exposure criteria, such as the

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Derived No- Effect Level values under the EU REACH program. In this project, three types of PK and PBPK models will be developed, utilizing the MEGen model generation application. QSAR estimations of chemical-specific parameters will be included, as well as accomodation of variations in urine production. Estimates of variability in human physiology will also be incorporated, to allow for Monte Carlo analysis of biomarker level concentrations. Validation of each of the model structures will be conducted with published datasets of representative biomarkers.

2009-A-375-ISES

A Systems Approach To Assessing Risk: The Role Of Metabolism Research In Describing And Predicting Exposure

J. F. Kenneke,1 C. S. Mazur,1 A. W. Garrison,1 C. K. Cunningham,1 R. D. Miller2; 1U.S. Environmental Protection Agency, Athens, GA, 2Student Services Authority, Athens, GA

An important component of assessing risk is defining the exposure of a chemical stressor to a target organism. Often the chemical stressor is assumed to be a single compound even when it is comprised of different stereoisomers (e.g., pyrethroids and 1,2,4-triazole fungicides), which possess different physical, chemical and toxicological properties. Additional uncertainties in exposure assessment arise when the chemical undergoes transformation inside the organism, especially when the transformation is organ, species, and/or gender specific. Thus, a “simple” exposure scenario of a single chemical may ultimately involve multiple stressors (i.e., stereoisomers and metabolites) resulting in multiple internal exposures. Our research focuses on defining the internal exposure of chemical stressors in organisms. We utilize in vitro and in vivo metabolism assays, specific enzyme inhibitors, purified enzymes, and molecular docking to elucidate the kinetics and mechanisms of xenobiotic metabolism to deconvolute “simple” exposure scenarios. For example, we have shown that the exposure of triadimefon to liver microsomes from eight vertebrate species resulted in the formation of triadimenol in all cases; however, the exposure scenario is actually more complex. Triadimefon metabolism occurs via the reduction of a prochiral carbonyl that yields a unique set of four triadimenol stereoisomers for each species. The stereoisomers have different toxicities and degrees of binding with endogenous receptors (e.g., enzymes involved in steroidogenesis and nuclear receptors), which could impact the mode-of-action of triadimefon. The implications of this for risk assessment are worth considering because triadimefon exposure to human liver microsomes produces a significantly higher percentage of the more toxic stereoisomers than rat (i.e., rat results extrapolated to human may underpredict risk). Examples of the (1) stereoselective and gender specific metabolism of 1,2,4-traizole fungicides, (2) organ and species specific metabolism of bisphenol A, and (3) stereoselective metabolism of pyrethroids for use in exposure reconstruction will also be presented.

2009-A-511-ISES

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Interpretation Of Exposure Regression Model For Exposure: Towards A Communicable Public Health Message

O. Jolliet, B. Hong, X. Jiang, Q. Chen, B. Gillespie, D. Garabrant; University of Michigan, Ann Arbor, MI

The University of Michigan Dioxin Exposure Study conducted a human exposure study in response to concerns that the population in Midland and Saginaw - Michigan, nearby the Dow Chemical Company may have increased dioxin-like body burdens. Linear regression was used to identify factors associated with serum dioxins of 946 people in the contaminated area and in a referent population (Garabrant et al, 2009, EHP, 117, 818-824). The resulting parameter estimates are however often difficult to interpret. This paper aims to show the relative influence of individual factors on the population (e.g., large influence on a few individuals versus small influence on many individuals). A graphic-based approach has been developed to visualize results: The influence on each participant is reported as a positive or negative bar, expressing the amount by which the serum dioxin concentration is increased or decreased: e.g. a value of +0.5 means a 50% increase, a value of -0.5 a 50% decrease due to the effect of the variable. The number of participant for each value is represented on the X-axis, ordering participants from smallest to largest effect (maximum effect on an individual). The area under the curve represents the influence of the considered factor on the overall population. Applying the approach to serum total TEQ and to the five main TEQ contributors, we show that: a)For TEQ and all main contributors, demographic variables (age, BMI, breastfeeding and smoking) play a dominant role and effect of age is higher for females. b)For TEQ and most congeners, living in Midland or Saginaw from 1960 to 1979 leads to a significant but relatively limited increase in serum concentration of around 20%. Fishing or water activities may also lead to a comparable increase in serum concentration. c)2,3,7,8 TCDD shows the highest variations for both demographic variable and the Dow related variables.

2009-A-559-ISES

Identifying Known Trace Target Compounds Within Complex Material Emissions Profiles By Employing Advanced Chemometric Techniques In Combination With Deconvolution Algorithms

P. G. Hughes; Markes International Ltd., Llantrisant, United Kingdom

Dr Peter Hughes1 and Dr Gerhard Horner2 1. Markes International Ltd. 2. ALMSCO International Ltd. Concern is growing about emissions of volatile organic compounds (VOCs) and semi-VOCs from materials due to their potential impact on human health/comfort. Manufacturers of construction products, furnishings, furniture, car trim components and consumer products need to monitor emissions of individual and total VOCs to assess the

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environmental impact of their products indoors and in vehicle cabins. VOCs/SVOCs are measured using conventional emission chambers/cells to simulate real-world conditions (ISO/EN 16000 -9/-10, ENV 13419) or by direct thermal desorption/ extraction. In either case, thermal desorption (TD) with GC-MS is required for analysis. TD-GC-MS often produces very complex chromatograms making it difficult and time-consuming to confidently identify key odorous and toxic compounds which may only be present at trace levels This paper describes the development and use of a novel software package, known as TargetView, for simplifying and improving the identification of trace level compounds within complex emissions profiles. TargetView is a post run software program which incorporates advanced chemometric techniques, e.g., pattern recognition software, to identify known target compounds. The software also incorporates novel approaches for compensating baseline anomalies and deconvoluting co-eluting species within GC/MS data. The analysis of GCMS data using TargetView follows a defined protocol. A dynamic baseline compensation algorithm removes the baseline of each spectrum. The baseline-free peak spectra are then processed by an innovative deconvolution algorithm. The deconvolved spectra and the target spectra are cross matched for compound identification. When a target compound is found a match co-efficient is calculated (0 to 1) and a plot of match value against peak apex RT created. A report is generated showing positive compound identification.

2009-A-341-ISES

Potential For Metabolomics-based Markers Of Exposure: Encouraging Evidence From Studies Using Animal Models

T. Collette; US EPA, Athens, GA

Genomic techniques (transcriptomics, proteomics, and metabolomics) have the potential to significantly improve the way chemical risk is managed in the 21st century. Indeed, a significant amount of research has been devoted to the use of these techniques to screen chemicals for hazardous effects. However, changes in transcripts, proteins, and endogenous metabolites may, in some cases, be more-certain indicators of chemical exposures than of apical chemical effects. Nonetheless, these powerful new techniques have rarely been applied as markers of exposure. In comparison to (or in combination with) conventional biomarkers, genomic markers of exposure offer considerable promise. Note that genomic markers are a unique pattern of a large number and wide variety of transcript, protein, or endogenous metabolite changes. These signatures may be more informative and more chemical-specific than a conventional biomarker. Also, taking advantage of the earlier research in genomic markers for effects, these markers of exposure may, in some cases, be able to identify exposure to a specific mode-of-action-active chemical. Indeed, genomic markers can sometimes serve as a linkage across the source-to-outcome continuum, functioning concomitantly as markers of exposure, dose characterization, and effects.

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Metabolomics may be a particularly powerful genomic tool for developing markers for both human and ecological exposures. For human exposures, it is important to note that metabolomics can be conducted effectively on biofluids that can be collected non-invasively from humans (e.g., urine, breath condensate, saliva). For ecological exposures, it is important to note that metabolomics can be conducted effectively without the need for a sequenced genome, and that metabolism is often conserved across species. We will illustrate here the advantages of metabolomics for developing markers of exposure, using results from studies with, e.g., fathead minnows, rodents and cell-cultures exposed to a variety of chemical stressors.

2009-A-377-ISES

Analysis Of Low Dose Synergy Literature For Use In Screening Chemical Co-exposures For Risk Assessment

R. T. Zaleski,1 *. HESI Risk Assessment Methodology Committee,2 M. Embry3; 1ExxonMobil Biomedical Sciences, Inc., Annandale, NJ, 2ILSI Health and Environmental Sciencies Institute, Washington, DC, 3ILSI Health and Environmental Sciences Institute, Washington, DC

There is a critical need to better understand the consequences of co-exposures to substances at environmentally relevant concentrations. Default assumptions of dose or response additivity, as appropriate, have been used to assess the joint toxicity of chemicals, due to the fact that it is not possible to perform toxicity tests on all combinations. In order to develop a screening approach to prioritize chemical mixtures or co-exposures for more detailed assessment, it is essential to know whether synergistic interactions can occur at low, environmentally relevant exposure levels. Studies present in the literature demonstrating synergism in mammalian test systems were identified, with emphasis on studies performed at doses close to the individual chemicals’ NOAELs or LOAELs in the test systems. This literature search identified data for 204 chemicals by in-depth critical review of 90 unique references. Few studies, however, included quantitative estimates of low dose synergy; interaction magnitude calculations were included in only 11 articles. Quantitative methodology varied across studies in terms of the null hypothesis, response measured, point of departure (POD), and whether the slope of the dose-response curve was considered. The values reported are not directly comparable because of the various definitions and quantification of synergy used. In general, the magnitude of any low dose synergy reported was relatively modest. It is anticipated that this analysis will be considered in developing an approach for quantitative risk assessment of chemical mixtures and co-exposures, including use of a Threshold of Toxicological Concern for screening and prioritization. Prior to this, it is recommended that consistent approaches be applied in synergy quantification, including that: synergy be defined in terms of departure from dose additivity; uniform procedures be developed for assessing synergy at low exposures; and the POD for calculating synergy be standardized.

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Symposium

R-SY201: Approaches to Interpreting Biomonitoring Data from Population-level Studies

Biomonitoring is the measurement of chemicals present in human blood, urine or other tissues and is used as an indicator of human exposure to these chemicals. In exposure assessment methodology, biomonitoring is considered to be the gold standard. As such, an increasing number of national, targeted population, and community-level biomonitoring programs are being established. However, detection and quantification of environmental chemicals in the population raises the question “Do these levels pose a risk to human health?” Approaches to interpreting biomonitoring data from population-level studies are often limited to trend analysis and comparisons with other populations. Regulatory bodies and public health agencies have established tissue level guidance for only a few substances measured in biomonitoring studies (e.g. lead, mercury, cadmium). For mercury, blood guidance values were established on the basis of epidemiological data. However, this kind of data does not exist for most substances and alternative approaches to establishing health-based guidance need to be considered. Use of occupational biomonitoring data, Biomonitoring Equivalents and human biomonitoring values should be fully examined to help interpret output from large-scale biomonitoring studies. With an increasing number of biomonitoring programs being established and the resulting need for interpretation of these data against toxicology-based criteria, this symposium will consider the different approaches which have been developed to deal with this data gap. The symposium will be divided into a brief introduction and four 15 minute presentations, followed by a 25 minute question period. Presentations 1. Human Biomonitoring and Reference Values: An overview of Germany’s development and use of HBM values (level I and level II) to interpret data from GerES. Presenter: Jurgen Angerer, Human Biomonitoring Commission, Germany. 2. Blood Guidance Values for Methylmercury for Canada. presenter: Angela Li-Muller, Health Canada 3. Biomonitoring and Epidemiology: A Case-study of Cholorpyrifos. Presenter: Carol Burns, Dow Chemical 4. Biological Equivalents as Screening Tools for Interpretation of Human Biomonitoring Data. Presenter: Sean Hayes, Summit Toxicology

2009-P-599-ISES

The German Human Biomonitoring Commission Reference- and HBM-Values

J. Angerer,1 U. Ewers,2 M. Kolossa-Gehring,3 C. Schulz,3 M. Wilhelm4; 1BGFA Research Institute of Occupational Medicine, Ruhr University Bochum, Bochum, Germany, 2Institute of Hygiene of the Ruhr, Gelsenkirchen, Germany, 3German Federal Environmental Agency, Berlin, Germany, 4Department of Hygiene, Social and Environmental Medicine, Ruhr-University Bochum, Bochum, Germany

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The German HBM-commission was founded in 1992. Experts from universities and government agencies are consulting the president of the Federal Environmental Agency of Germany with regard to exposure and health risk assessment of individuals and population groups exposed to chemicals from the environment. Human Biological Monitoring (HBM) is considered as the method of choice to determine internal exposure of individuals thus supplying a basis for estimating health risks and - if necessary - for risk management. A prerequisite for applying HBM is the availability of reliable analytical methods for the determination of biomarkers in human body fluids. Moreover, reference values and health-based biological exposure limit values are required for the interpretation of HBM results. With respect to analytical methods the HBM commission relies on the collection of proven and reliable standard operating procedures which are elaborated and published by the Deutsche Forschungsgemeinschaft. Reference values are defined as the 95th percentiles of the concentrations of a substance in human biological material; they are statistically derived from representative groups of the general population. The German Environmental Surveys represent the most important basis for establishing these values. Reference values allow to classify the exposure level of an individual or of a group of individuals as elevated or not elevated with regard to the current background exposure of the population. HBM values are health-based biological exposure limits based on exposure-effect-relationships. The HBM-commission tries to establish two different kinds of HBM values: HBM I is defined as a concentration, below which there is no risk for adverse health effects. HBM II is defined as an action-value, above which there is an increased risk for adverse health effects in sensitive individuals or population groups. Based on the reference and HBM values (metals, POP, pesticides, phthalates etc.) that were established in the past years the principles of their evaluation, their perception by health professionals and by the population, their documentation and their permanent re-evaluation will be discussed.

2009-P-452-ISES

Biomonitoring Reference Values: Blood Guidance Values for Methylmercuy for Canada

A. Li-Muller; Health Canada, Toronto, ON, Canada

Exposure to methylmercury (MeHg) from fish and marine mammal consumption continues to present a public health concern in Canada and elsewhere. In the seventies, Health Canada established a set of biomonitoring blood guidance values in response to unusually high mercury levels observed in a number of First Nation communities. These guidance values are applicable to the general population of high fish consumers (e.g. first Nations and Inuit). In recent years, extensive toxicological and epidemiological evidence have indicated that neurotoxicity resulting from in utero exposure is the most sensitive

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health outcome Health Canada is currently conducting biomonitoring surveillance for mercury in a number of national and targeted population studies. These initiatives are measuring mercury in blood, urine, and/or hair of children, pregnant and lactating women, women of childbearing age, adult men and/or adult women above the childbearing age. To enable better interpretation and reporting of the results of these and other studies, Health Canada reviewed and updated existing Health Canada blood guidance values. This presentation describes our approach to new blood guidance values for methylmercury applicable to women of child bearing age and pregnant women for the protection of the fetus, infants and children, including adolescents. These new guidance values complement the existing blood guidance values for adult general population. We will present recommendation for associated public health actions, according to age, sex and level of exposure.

2009-P-450-ISES

Biomonitoring and Epidemiology: A Case-study of Chlorpyrifos

C. J. Burns; Dow Chemical Company, Midland, MI

Biomonitoring for chlorpyrifos (CPF) exposure dates back more than 40 years with the monthly monitoring of cholinesterase (ChE) inhibition among applicators and manufacturing workers. Urinary metabolites including 3,5,6-trichloro-2-pyridinol (TCPy) and dialkylphosphates (DAP) have the benefits of being less invasive to collect and perhaps more sensitive than ChE inhibition as a biomarker of exposure. We evaluated the quantitative relation between measured red blood cell acetylcholinesterase (RBC AChE) and plasma butyrylcholinesterase (BuChE) activities with exposure to CPF by measurement of urinary TCPy in a year-long study of CPF manufacturing workers and a referent group. RBC AChE activity was unrelated to exposure, up to the maximum of approximately 1,000 µg TCPy/g creatinine (Cr), while plasma BuChE activity was negatively related to urinary TCPy concentrations above approximately 110 µg TCPy/g Cr. No-effect levels for inhibition of plasma BuChE and RBC AChE corresponded to absorbed doses of CPF of approximately 5 and >50 µg/kg-d, respectively, consistent with previous no-effect level determinations in humans. These findings suggest that general population CPF exposure levels are substantially below the identified no-effect levels. These findings are important as epidemiologists make decisions regarding relevant cut points for analyses by exposure levels. Relative risks are often compared by above and below the limit of detection or by quartiles, regardless of the absolute levels of exposure. However, as the CPF case study demonstrates, analytical detections of biomarkers of exposure can occur far below the levels at which even early biomarkers of response can be observed; thus, health effects in humans at these levels may not be biologically plausible. We recommend that epidemiologists use such information to inform ranges selected for exposure-response analyses to improve the interpretability of their results.

2009-P-449-ISES

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Biomonitoring Equivalents (BEs) as Screening Tools for Interpretation of Human Biomonitoring Data

S. M. Hayes; Summit Toxicology, Lyons, CO

Increasingly sensitive analytical data on concentrations of chemicals in human biologic media such as blood or urine in persons from the general population are being generated by biomonitoring programs conducted by the U.S. Centers for Disease Control (CDC) through the National Health and Nutrition Examination Survey (NHANES) and other researchers, and more such programs are planned or ongoing, including the Canadian Health Measures Survey. Currently, few screening tools are available for interpretation of biomonitoring data in a health risk assessment context. In this presentation we describe the concept and implementation of Biomonitoring Equivalents (BEs), estimates of the concentration of a chemical or metabolite in a biological medium that is consistent with an existing exposure guidance value such as a tolerable daily intake (TDI) or reference dose (RfD). Key concepts regarding the derivation and communication of BE values will be presented. Approaches for deriving BE values include use of PBPK models, urinary mass balance assessments, and the direct use of measured biomarker concentrations in an internal dose-based risk assessment framework. We summarize the BE values derived to date for approximately 20 chemicals. We demonstrate use of the BE values to evaluate current biomonitoring data from NHANES for several chemicals to estimate margins between the BE values and measured biomarker concentrations in the general population for many of these chemicals. The resulting screening level evaluation of biomonitoring data can be used as one tool to classify chemicals into relative categories of low, medium, and high priority for risk assessment follow-up

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Platform

R-PL201: Time-Activity Patterns

2009-A-281-ISES

Microenvironment Exposure Weights Can Be Obtained From A Straightforward Statistical Model Of Time-location Data

R. deCastro,1 A. S. Geyh,2 A. Houseman,3 L. Ryan,4 J. D. Spengler5; 1Westat, Rockville, MD, 2Johns Hopkins Bloomberg School of Public Health, Baltimore, MD, 3Warren Alpert Medical School of Brown University, Providence, RI, 4Commonwealth Scientific and Industrial Research Organisation, North Ryde, New South Wales, Australia, 5Harvard School of Public Health, Boston, MA

Collection of time-location data through diaries is a common feature of personal exposure studies and is intended to provide a basis for time-weighted averaging in exposure assessment totaled across microenvironments. Particular difficulties posed by the outcome -- multiple non-ordered microenvironments -- have precluded routine statistical analysis, but such multinomial outcomes may be modeled within a regression framework using the generalized logit model (or discrete choice model). Conveniently, this model predicts the proportions of subjects in each microenvironment at each time interval. These proportions may be construed most usefully as exposure weights in a formulation of total exposure. This report introduces the generalized logit model and demonstrates its application to data from a study of schoolchildren (N = 95, 7-11 years old) in southern California who reported their time-location at 30-minute intervals in structured 24-hour diaries for 4 days per month for 12 months (June 1995-May 1996; N = 171,000). A generalized logit model of the proportion of subjects in each of five microenvironment -- indoor-home, indoor-school, indoor-other, commuting, outdoors -- shows that while subjects spent substantial time indoor-home, there was substantial variation for other microenvironments at all temporal scales. Consistent with a daily academic schedule, indoor-school time predominates at the 30-minute timescale. Yet, at the day and month timescales indoor-other predominates. This suggests that important longer-term exposures among schoolchildren may be missed because non-home and non-school microenvironments are not often monitored. The model also found that microenvironment location is most positively correlated with the previous 30-minute interval, tapering through the preceding 3 hours. Also discovered was that children in homes with >=5 televisions spent 21 percent less time outdoors than homes with <=2 TVs, while nonwhites spent 21 percent less time indoor-school than whites.

2009-A-288-ISES

Quantified Outdoor Micro-activity Data For Children Aged 7-12 Years Old

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P. Beamer,1 C. E. Luik,1 J. O. Leckie2; 1University of Arizona, Tucson, AZ, 2Stanford University, Stanford, CA

Estimation of aggregate exposure and risk requires detailed information regarding dermal contact and mouthing activities. Although many studies have been completed to assess micro-activities of young children (< 6 years of age) and identified differences in behavior by developmental stage, few have reported micro-activity contact behavior of older children. We have analyzed micro-level activity time series (MLATS) of older children to provide quantified values of contact behavior for exposure and risk assessment and evaluate how these behaviors change as a function of age and gender. We utilized MLATS for 18 children (11 female, 7 male) aged 7-12 years. The children were videotaped playing for 2 hours outdoors in suburban California. Video footage was transcribed into MLATS via Virtual Timing Device software. The videotapes were transcribed for contacts with the hands and the mouth. We calculated contact frequency, hourly duration and median duration of contact for 16 object categories. Median hand-to-mouth and object-to-mouth frequencies were 12.6 events/hr and 16.3 events/hr, respectively. The hourly mouthing duration was 0.4 and 1.0 min/hr with the hands and objects respectively. The median mouthing duration with hands and objects was 1 second. The median contact frequency for both hands combined was 595.4 events/hr with an hourly contact duration of 78.7 min/hr and a median contact duration of 3 seconds. There were no significant differences between gender with mouthing activity, however female children had longer and more frequent contacts with fabric, wood and floor surfaces. A significant negative correlation with age was determined between hand contact and floor surfaces. While these children had longer and more frequent contacts with clothes and footwear compared with younger children (1-6 years), the younger children had more frequent contacts with metal, plastic and floor surfaces. Contact frequencies in this study are higher than current U.S. EPA recommendations for this age group.

2009-A-231-ISES

Estimation Of 24hr NOx Exposure Level Of Children By A Time-activity Pattern

J. Zhang,1 Y. Zeng,2 X. Wang,3 Q. Zhao,2 P. Parasati2; 1Department of Environmental Pollution and Health, Chinese Research Academy of Environmental Sciences (CRAES), Beijing, China, 2Department of Occupational & Environmental Health Sciences, School of Public Health, Peking University Health Science Center, Beijing, China, 3Beijing Centers for Diseases Control and Prevention (CDC), Beijing, China

Objective To estimate children’s personal NOx exposure level by time-activity pattern combined with microenvironment monitoring. Methods The research was conducted in Qingdao and Beijing. Three primary schools were selected in each city. They were selected in light, middle, highly-polluted areas by traffic exhaust respectively. The air quality was monitored on campus (including school gate, playground, classroom); Ten children in grade three were selected in each school and personal 24-hour NOx exposure

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level and average NOx level at their household were measured by passive diffusion samplers provided by Chinese CDC. Meanwhile the information on children’s time-activity was collected via questionnaire. The adjusted NOx level at school gate was used to represent the NOx exposure of children in traffic vehicles to simulate the schoolchildren’s personal exposure level. The values estimated by the model were compared with adjusted monitoring results. Results Children have very regular time-activity pattern. They spend 96% of their time at home and school and the ratio of the time at school to time at home is 1.64:1; There were very similar NOx levels in the household for all children both in Beijing and in Qingdao. Personal 24 hr NOx exposure level estimated by time-activity pattern was 0.041 mg/m3, and it was highly associated with the traffic intensity. Meanwhile, the estimated personal exposure level was significantly correlated with the adjusted personal exposure level (r=0.785, p<0.01). The paired T-test showed that there was no significant difference (T=0.139, P>0.05) between them. Conclusion The evaluation of children’s exposure to NOx by the time-activity pattern model combined micro-environment measurements, has similar spatial variation as on-site measurement.

2009-A-363-ISES

Feasibility Of A Global Positioning System (GPS) Device For Time Location Analysis

K. Lee,1 J. Kim,1 D. H. Bennett,2 C. Teague,2 B. Ritz,3 D. Cassady,2 I. Hertz-Picciotto2; 1Seoul National University, Seoul, Republic of Korea, 2University of California, Davis, CA, 3University of California, Los Angeles, CA

There is a great challenge to obtain accurate time location data for exposure assessment. Global positioning system (GPS) can potentially be a useful tool. The purpose of this study is to evaluate if time and coordinate data logged by a GPS device can be used to determine time-location information in a field study. In this study, the time location data were recorded by a small and portable GPS device (MT-4100, Skytrx). Thirty-two subjects, living within a 2-hour drive of Sacramento, California, were given the device for seven day periods. We analyzed the 5 middle days. Because the GPS device does not log data while inside building, a logged GPS time was assumed to be either time spent outdoors or in transit. We assume the last recorded location prior to a period of no records is the location of the indoor location. Among the 32 subjects, 17 subjects provided information for 5 days with time spend outdoors. There were days where no time outdoors was recorded. These days may be explained in two ways; 1) subjects did not carry the GPS device, or 2) subjects did not leave the house. On average, 4.1 days of time location data were collected from the possible 5 days. All subjects stayed mostly in their own houses on average of 15.5 hours per day. Average outdoor-activity time of the 32 subjects was 2.1 hours per day. Outdoor times in weekend and weekday were 2.1 hours and 1.9 hours, respectively. The logged GPS data demonstrated that it could be useful and feasible to collect subject’s time-location pattern and GPS technology might be a useful tool for exposure science.

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2009-A-413-ISES

An Analysis Of Time-activity Pattern Of California Residents And The Evaluation Of Sampling Techniques

D. H. Bennett,1 X. Wu,1 D. Cassady,1 K. Lee,2 B. Ritz,3 I. Hertz-Picciotto1; 1UC Davis, Davis, CA, 2Seoul National University, Seoul, Republic of Korea, 3UCLA, Los Angeles, CA

Time-activity data are essential for conducting exposure assessments, however, there is little longitudinal time-activity data available. This study examines longitudinal consistency of time-activity across seasons, and compares compliance obtained from different sampling platforms. Time-activity-location data, i.e., time spent in multiple microenvironments (e.g., residence, transit, places for work/shopping/eating/errands) and on specific activities (e.g., work and sleep), were collected from California residents in three age groups, including children (<9-year-old), parents of young children, and seniors. Two platforms were employed: (1) telephone interviews on a weekday and a weekend day once a year for three years for a large cohort (N=1068), and (2) two versions of a web-based survey (interactive and non-interactive) for 24-hour recall were completed for a weekday and a weekend day 6 times over an 18-month period for a sub-cohort (N=355). To determine subject compliance, we examined the longitudinal variation of the count of total daily records and found consistent compliance throughout the study. Parents had similar activity counts for the interactive and non-interactive versions, indicating ability and willingness to complete the survey, but seniors performed better on the non-interactive version. Sampling compliance between sampling platforms will also be examined. Generalized linear mixed models and mixed-effect mixed-distribution models were used to examine the longitudinal variation of time spent in various locations and to determine if there was significant variation between weekend versus weekdays and by season. For many of the locations people spend time, such as their home and workplaces, inter-person variability exceeded intra-person variability. There was more significant variation between weekend and weekdays for children and parents than for seniors, probably due to their relatively flexible time budget.

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Symposium

R-SY202: Demonstrations of Emerging Methods for Comprehensive Measurement of Personal Exposures Including Diet, Physical Activity, Stress and Biological Response in the NIH Genes, Environment, and Health Initiative

The US Department of Health and Human Services and the National Institutes of Health established the NIH Genes, Environment and Health Initiative in 2006 to lay a foundation for future studies in the interaction between Genetic and Environmental factors in human disease. An initial effort of this program has been the establishment of improved techniques for measuring personal exposures including chemical exposures, diet, physical activity, psychosocial stress and drug abuse as well as biomarkers of the initial biological response to those factors. These measures are intended to give a more comprehensive view of exposure including information on multiple analytes as well as temporal and spatial variability in exposures. An additional primary focus is on the development of measures that are minimally obtrusive – which require little to no participant burden or minimally invasive monitoring of biomarkers. An intermediate goal of the program is to integrate measures of exposure to change the perspective of exposure from being a single event to an integrated continuum. It is expected that, for instance, simultaneous measurement of PM and Ozone exposure in conjunction with detailed analysis of physical activity could add information about the correlation between exposure and increased activity, potentially signaling an increased risk of asthmatic events in susceptible populations. This expanded demonstration session will feature an overview presentation of the Exposure Biology Program, rapid overviews (1 minute/1 slide presentation) by EBP grantees and hands-on demonstrations of prototypic tools being developed by several of the program’s grantees. These will include a variety of new measures for each of the emphases of the Exposure biology program.

2009-P-159-ISES

Wearable Electronic System for Objective Dietary and Physical Activity Assessment

M. Sun; University of Pittsburgh, Pittsburgh, PA

Currently, self-reporting is the main method for diet and physical activity assessment. However, this method is subject to substantial error due to bias and behavior change of individuals during the reporting period. We present an electronic system to monitor both dietary and physical activity continuously for extended periods. The design of the wearable unit of the system is a decorative pendant-like device suspended on a chain or line. This device contains a miniature camera to record video at a selected frame rate. It also contains electronic circuits for the camera and sensor interfaces, data compression, and data storage. The viewing angle of the camera is set such that, at normal head

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position, the central visual fields of the human eyes and the camera lens overlap. An optical sensor below the camera estimates food portion size by projecting a light pattern within known parameters. The image data, along with other sensor measurements, are compressed and stored in a multi-gigabyte flash memory within the device. The recorded data are uploaded to a computer regularly (e.g., every week) where advanced multimedia data processing algorithms, including food portion size and physical activity estimations, are utilized to compute calories and nutrients in foods and energy expenditure during physical activity. Our current version of the device contains only essential sensor components. Subsequent versions of our wearable system may contain additional sensors. Our ultimate goal is to make the device as versatile as possible so it can be used as a measurement platform in the study of exposure biology.

2009-P-161-ISES

A Tool for Geospatial Analysis of Physical Activity: Physical Activity Location Measurement System (PALMS)

K. Patrick; University of California at San Diego, La Jolla, CA

The PALMS project will: a) develop a system to concurrently collect physical activity (PA), location (GPS) and momentary assessment data from free-living humans over extended periods of time; and b) enable modeling, analysis and sharing of these data via a cyberinfrastructure for researchers. PALMS began with samples of data on heart rate, accelerometer, GPS, and participant satisfaction data from subjects who provided hours of heart rate and motion data and hours of GPS data over 95+ days. Subjects completed a customized PA Spatial Analysis interview to differentiate between types of PA and to help develop initial algorithms to identify PA type. Other development has been based upon GPS and accelerometer data on 800+ teenagers collected in another study. These data are being used to explore methods of variable creation, visualization, algorithm development and analyses. Continued usability testing of PALMS is planned with older adults from retirement communities in San Diego. This will extend PALMS capabilities into supporting research with older populations as well as expand the number of sensors and data sources to include ambulatory blood pressure and respiration via the Zehpyr Bioharness device. Work is also underway on scripts and systems for mobile phone based ecological momentary assessment to be used concurrently with sensor and GPS data. The PALMS Cyberinfrastructure (PALMS-CI) is being designed as a scalable, policy-driven system to allow researchers to specify: a) type of information kept on study participants; device used to collect data; c) calculation and data visualization algorithms used; and d) format for data export. The PALMS-CI’s will support multiple users in multiple locations via web and grid-based computational systems. Using the PALMS-CI’s policy mechanisms, researchers will have control over the privileges and capabilities of research staff either on a role or individual basis, with controlled data sharing and HIPAA-compliance.

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2009-P-164-ISES

Real-time Self-report and Geospatial Localization of Exposure to Stressors and Drugs of Abuse

K. Preston; NIDA, Baltimore, MD

Assessment of exposure to drugs and psychosocial stress is complicated by the fact that each is often transient and difficult to recall accurately. Assessment of their connections with one another, and of their genetic and environmental determinants, is complicated by the multidirectionality of the causal connections and by the elusive nature of what constitutes the environment. To address these problems, our laboratory is combining two real-time data-collection technologies: handheld electronic diaries for collection of self-reports of drug use and stress, and Global Positioning System (GPS) devices to record the location. Participants use the handheld electronic diaries to record events as they occur and to report recent or ongoing events in response to randomly timed prompts throughout the day, a technique called Ecological Momentary Assessment (EMA). Participants also carry GPS devices to track their whereabouts and to record the location of self-reported events, with a likely spatial resolution of several meters. Broadening the definition of environmental factors, we will evaluate “neighborhood-level” exposures to drugs and stress measured in terms of specially developed indices (e.g., Neighborhood Psychosocial Hazards scale) based on objective statistical data available from public sources and independent of self-report. Overall environmental exposure will be calculated from participants’ locations and the neighborhood-level risk indicators. For comparison, we will also assess drug use through retrospective interviews and from biological specimens (urine and sweat). Stress will be assessed through standardized questionnaires and physiological measures (allostatic load, a physiological marker of long-term cumulative stress) and laboratory sessions examining responsiveness to standardized stressors. The result is expected to be a set of field-deployable, state-of-the-art tools to study gene-environment interactions affecting drug use and stress.

2009-P-165-ISES

AutoSense: A Wireless Sensor System to Quantify Personal Exposures to Psychosocial Stress and Alcohol in Natural Environments

S. Kumar; University of Memphis, Memphis, TN

In the AutoSense project, we have developed a completely wireless sensor system that provides continuous measurement of heart rate, heart rate variability, respiration rate, skin conductance, pulse wave velocity (for estimating arterial blood pressure), skin temperature, and physical activity, to provide a comprehensive physiological measurement of stress response. It also has an Interstitial Fluid (ISF) based sensor to continuously measure blood alcohol concentration in real-time. The sensors are hosted on

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a tiny computing platform called wireless sensor mote (similar form factor as an SD card that is used in digital cameras). Several motes are placed at different locations on the body (around the chest area and forearm). There is no wiring involved either between the motes and the sensors or between the motes themselves; the system is completely wireless. The motes have Analog to Digital converters and standalone microcontrollers that can be used to filter out noises from the signals and extract features of interest in real-time. All motes on the body communicate wirelessly to a cell phone, which has a visual display, a more powerful microprocessor, and a wireless link to the Internet via the cellular network. New sensors can be added to AutoSense and existing ones removed without affecting the operation of the rest of the sensor system. Wiring free configuration and tiny form factor make AutoSense suitable for wearing by healthy subjects in their natural environments. The energy-efficient AutoSense system can run for multiple days without a need to change batteries. These features together with low cost make AutoSense an appropriate field deployable tool for use in large scale field studies for simultaneous collection of personal exposures to psychosocial stress and addictive substances in subjects’ natural environments.

2009-P-170-ISES

A Wearable & Wireless Sensor System for Real-time Monitoring of Toxic Environmental Volatile Organic Compounds

N. Tao; Arizona State University, Tempe, AZ

Evidence has shown that the recent increases in chronic diseases, such as asthma, diabetes and autism, are linked to the exposure of individuals to various environmental pollutants. In order to fully establish the correlation between the diseases with specific pollutants, new tools for measuring personal environmental exposures are required. We have been developing a wearable wireless system for real-time monitoring of personal exposure to environmental toxicants. The system is a palm-sized detection unit, housing a sensor cartridge, sample delivery and conditioning components, and electronic circuits for signal processing. It also has a wireless communication chip that can instantaneously transmit the sensor signals to a cell phone where the data are processed, displayed and stored. High sensitivity and selectivity are accomplished through the use of novel tuning fork sensor modified by molecularly imprinted polymers. The system can detect toxic volatile organic compounds (VOCs) under high concentrations of common interferents from flavors and fragrances. We have tested the system by measuring volatile toxic petroleum derivatives in laboratories, at a gas station, and at the Sky Harbor International airport (Phoenix), and validated the results by comparative studies using conventional gas chromatography (GC) and mass spectrometry (MS) equipment.

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Platform

R-PL202: Phthalates and Flame Retardants

2009-A-374-ISES

Phthalate Exposures In Various Polyvinylchloride Processing Industries

H. M. Koch,1 T. Weiss,1 L. Neumeister,2 J. Stork,3 T. Brüning1; 1Research Institute of Occupational Medicine (BGFA), Bochum, Germany, 2Berufsgenossenschaft Energie Textil Elektro (BG ETE), Cologne, Germany, 3Audi AG, Ingolstadt, Germany

Phthalates like DEHP (Diethylhexylphthalate), DiNP (Diisononylphthalate) and DiDP (Diisodecylphthalate) are high volume industrial chemicals mainly used for plasticizing PVC. While exposure of the general population is well described, data on occupational exposures are sparse. Within this study we examined 41 employees in different PVC processing industries (electric cable production, hosing and tubing, automotive industry) from six different workplaces (extrusion, hotwelding, heatcutting, mixing, recycling, underbody coating) regarding their exposure to DEHP, DiNP and DiDP. We determined the individual internal exposure using biological monitoring. For this purpose we collected pre- and post-shift urine samples and analysed them for secondary oxidised metabolites, which are the major urinary metabolites. In some cases we also performed ambient monitoring using personal air samplers. Air measurements indicated that external exposures to DEHP were between 0.023 and 0.56 mg/m3 and to DiNP between 0.026 and 0.41 mg/m3 (no DiDP was detectable). These values are considerably below the German occupational limit value (MAK-value) for DEHP (10 mg/m3). Results varied strongly both between identical and different workplaces. Biomonitoring results showed significant work-related exposures to DEHP, DiNP and DiDP. In contrast to ambient monitoring, we found considerable differences in exposure for the different workplaces. Employees in hotwelding and in underbody coating (cold plastisol application) had highest internal exposures which were 20 to 50-times the background levels of the general population. Surprisingly, pre-shift samples (taken at the beginning of the work-week) were also considerably elevated. In conclusion, biomonitoring can be considered to be a specific and sensitive tool to assess phthalate exposure at the workplace. Additional research regarding routes of uptake, the significance of dermal exposures and elimination (high pre-shift values) is warranted.

2009-A-387-ISES

Chemicals Used In Personal Care Products: Biomonitoring Advances

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A. M. Calafat, M. J. Silva, X. Ye, L. Wong, L. L. Needham; Centers for Disease Control and Prevention, Atlanta, GA

Background/Objectives: Synthetic chemicals such as phthalates (plasticizers), parabens (preservatives), triclosan (antimicrobial agent) and benzophenone-3 (sunscreen agent) can be used in personal care products, medications, paints, adhesives, and in some medical products. Data on the potential effects of these compounds on human health are limited and, at times, even contradictory, but several of these chemicals have demonstrated toxicity in experimental animals. For the past ten years, we have developed biomonitoring programs to assess human exposure to several compounds present both as “active” and “inactive” ingredients in personal care products. Methods: We have analyzed biological samples (e.g., urine, serum) collected from the general population using state of the art analytical methods, namely isotope dilution tandem mass spectrometry. Results: The urinary concentrations of monoethyl phthalate (MEP) have been associated with the reported use of personal care products both in men and women. MEP is the primary metabolite of diethyl phthalate, a compound commonly used as a fragrance vehicle in personal care products. The urinary concentrations of the sunscreen agent benzophenone-3 were significantly higher among men than women and among whites compared to blacks. Exposure to triclosan and parabens also follows specific demographic patterns. Conclusions/Implications: Exposure to several these chemicals commonly used in personal care products is prevalent in the general U.S. population. The observed differences by sex, age and race/ethnicity probably reflect differences in lifestyle (e.g., use of personal care products containing these compounds). The identification of personal care products as contributors to these chemicals body-burden is an important step in exposure characterization. Further work is needed to identify additional predictors of exposure to these synthetic chemicals.

2009-A-512-ISES

Gas-phase Emissions Of Phthalate Plasticizer From Vinyl Flooring - Prioritizing Exposure And Risk

J. C. Little; Virginia Tech, Blacksburg, VA

Phthalate esters have been recognized as major indoor pollutants. Di-2-ethylhexyl phthalate (DEHP) is most widely used phthalate. Exposure to DEHP at environmental levels may adversely affect human reproductive system development. The mechanisms governing emission of DEHP from consumer pro ductsare still not fully understood. In this paper, the emission of di-2-ethylhexyl phthalate (DEHP) from vinyl flooring was measured in a specially-designed stainless steel chamber. The gas-phase concentration in the chamber reached a steady state level of 0.8 µg/m3 after about 30 days. By increasing the area of vinyl flooring and decreasing that of the stainless steel surface, the time to reach steady state was significantly reduced. The strong adsorption of DEHP onto the

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stainless steel surface was explicitly measured, and was found to follow a simple linear relationship. Good agreement was subsequently obtained between the predictions of a fundamental emissions model and the gas-phase DEHP chamber concentrations, without resorting to fitting of model parameters. Based on this fundamental understanding of the emission process, residential exposure can be estimated and then combined with an estimate of toxicity (obtained from EPA's ToxCast Program) to get risk. The overall approach provides a convenient screening level risk assessment for rapid prioritization of indoor sources most harmful to human health.

2009-A-245-ISES

Association Between Phthalates Exposure And Glutathione S-transferase M1 Genotype On Estrogen-dependant Diseases

P. C. Huang,1 E. M. Tsai,2 W. F. Li,1 P. C. Liao,3 M. C. Chung,1 Y. H. Wang,1 S. L. Wang1; 1Division of Environmental Health and Occupational Medicine, National Health Research Institutes, Miaoli County, Taiwan, 2Department of Obstetrics and Gynecology, Kaohsiung Medical University Hospital, Kaohsiung City, Taiwan, 3Department of Environmental and Occupational Health, Medical College, National Cheng Kung University, Tainan City, Taiwan

Background and Objective. The etiology of estrogen-dependant diseases (EDDs), such as endometriosis, adenomyosis, leiomyoma, are still unclear. Recent studies showed possible association among endocrine disruptors, genetic factors and endometriosis. However, few studies explore the synergetic effects of phthalates exposure, widely used as plasticizers, and genetic factors on EDDs. The aim is to investigate the association between phthalate metabolites and genotype of glutathione S-transferase M1 (GSTM1) in women with EDDs. Methods. We recruited patients and controls that underwent laparotomy and had pathological confirmation with and without EDDs from the Department of Obstetrics and Gynecology at the Kaohsiung Medical University Hospital in Taiwan during 2005 to 2007. Blood and spot urine samples were collected from 29 endometriosis, 16 adenomyosis, 36 leiomyoma, and 29 controls. Lymphocytes were obtained from blood (8 ml) for GSTM1 genotyping by polymerase chain reaction. Seven urinary phthalate metabolites were analyzed using liquid chromatography tandem mass spectrometer (LC-MS/MS). Results. Median levels of urinary mono-butyl phthalate (MBP) in endometriosis (87.7 v.s. 58.0 μg/g creatinine) and Σ mono ethylhexyl phthalate (MEHP) in leiomyoma (52.1 v.s. 18.9 μg/g creatinine) were significantly higher than in control group. GSTM1 in adenomyosis was significantly increased (Odd ratio (OR) = 5.2; 95% CI: 1.1-24.6) even after the adjustment of age and phthalate exposure. OR for ΣMEHP exposure in leiomyoma was 1.53 (1.04-2.24) folds higher than in the control. The combination of GSTM1 deletion and high ΣMEHP in adenomyosis (OR=12.0) and leiomyoma (OR=7.1) showed significantly increased than those with normal GSTM1 and low ΣMEHP after adjustment of age.

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Conclusion. We suggested that phthalate exposure may increase the risk of adenomyosis and leiomyoma in women with GSTM1 deletion.

2009-A-600-ISES

PBDEs In House Dust And Human Placenta - Results From An Exposure Study In Denmark

M. Frederiksen,1 K. Vorkamp,2 M. Thomsen,3 L. E. Knudsen1; 1Institute of Public Health, University of Copenhagen, Copenhagen, Denmark, 2National Environmental Research Institute, Dept. of Environmental Chemistry and Microbiology, Aarhus University, Aarhus, Denmark, 3National Environmental Research Institute, Dept. of Policy Analysis, Aarhus University, Aarhus, Denmark

The indoor environment is one of the most important human exposure sources for polybrominated diphenyl ethers (PBDEs). Several studies have shown the importance of dust as a source of exposure, however, many different sampling techniques have been applied. The variability in dust sampling is not well studied, thus in the current study a second round of dust sampling was performed three months after the initial sampling; both samplings were based on domestic vacuum cleaner bags. The dust samples were dominated by BDE-209 (54.5 - 95380 ng/ dw), which on average made up 84 % of the total PBDE (76.8 - 95410 ng/g dw). A single sample had very high levels of BDE-209, which were approximately one order of magnitude higher than the second highest and more than two orders higher than the median, the high level was observed in both sampling rounds. Preliminary comparison of the two dust samplings showed good correlations, particularly for BDE-47 and -99, indicating that a single sample is representative for the general contamination level. Furthermore, a statistically significant correlation was observed for BDE-47 in house dust and placental tissue of residents after planned caesarean section (p = 0.048, r = 0.29). Like dust, the placental tissue was dominated by BDE-209 (<0.28 - 5.5 ng/g lw). For this congener there was not observed any correlation between dust and placental tissue, however, uptake mechanisms and degradation processes are poorly understood for BDE-209. The exposure study also includes maternal and umbilical cord plasma as well as breast milk, however, the analyses of these matrices are still in progress. Keywords: flame retardants, PBDE, dust, placenta.

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Interactive Poster

R-IP201: Measuring, Modeling, and Managing Urban Air Contaminants

2009-A-267-ISES

Spatial And Temporal Distributions Of PM2.5 Components Within New York City

M. Lippmann, R. E. Peltier; New York University School of Medicine, Tuxedo, NY

In earlier work based on PM2.5 speciation network data in and near New York City (NYC), we showed that nickel (Ni) concentrations were much higher in NYC than in adjacent states, and that NYC levels, but not those in nearby states, were much higher in the winter than in summer (Peltier et al. 2009). However, all of the speciation sites in NYC were in the northern half of the city. In a follow-up study of outdoor PM2.5 component concentrations throughout NYC, we collected 8 weeklong filter samples at 10 sites in both winter and summer, and measured the concentrations of the elements by x-ray fluorescence (XRF). The resulting data, together with speciation network site data, were used to construct seasonal average concentration isopleth maps for Ni and vanadium (V). As expected, Ni was much higher in Bronx than in Brooklyn, and much higher in winter than in summer, while V had little seasonal variation, and was somewhat higher in Brooklyn than in Bronx (Peltier and Lippmann 2009). The highest winter Ni concentrations observed under ambient conditions were similar to those from studies of the effects of subchronic inhalation exposures to concentrated ambient air PM2.5 in mice that showed cardiac function effects in mice. In tis paper we will present spatial and seasonal distributions of ~33 other elements, including tracers of traffic (e.g. elemental carbon, Pb, and Zn), resuspended road dust (Fe, Si, Ca, Mn, Al, and Ti), and biomass burning (elemental carbon, K, and Ca).

2009-A-286-ISES

Development Of A Personal Exposure Aerosol Screening Model: Model Description And Evaluation Of A Hybrid Dispersion & Aerosol Dynamics Model Against Ambient Measurements

S. Lee,1 C. O. Stanier,1 N. Riemer,2 M. West,2 R. A. Zaveri,3 K. Moore,4 C. Sioutas,5 R. Delfino,6 A. Ayala,7 T. Sax7; 1University of Iowa, Iowa city, IA, 2University of Illinois, Urbana-Champaign, IL, 3PNNL, Seattle, WA, 4University Southern California, LA, CA, 5University Southern California,, LA, CA, 6University of California, Irvine, CA, 7California Environmental Protection Agency, Sacramento, CA

There is a need for validated exposure models that bring together meteorology, source activity, plume processing and aerosol dynamics. Model-based exposure tools are

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expected to have a key role in health impact studies and in urban/transportation planning applications. This has motivated the development of a Personal Exposure Aerosol Screening (PEASM). Since full calculation of the associated aerosol dynamics and thermodynamics is computationally expensive, PEASM uses a two stage calculation approach, first calculating vehicular carbon monoxide at high spatial resolution (but low computational cost), and then in a 2nd pass implementing aerosol dynamics on spatial subdomains upwind of receptors of interest. The first stage of computation uses a GIS-based road network, an adaptive grid, CALINE4 line source dispersion, and meteorology from the Weather Research and Forecasting (WRF) model. The current development status of this model and its evaluation against highly time resolved data from the Harbor Communities Monitoring Study will be presented. Measured variables include particle number and particle size distribution measured at over 14 sites. This study was conducted from mid-February to mid-December 2007 to investigate diurnal, seasonal and spatial patterns. Total number concentration varied up to factor of 10 (<10,000 cm-3 up to 90,000 cm-3 for hourly averages calculated by month). The road maker was developed with ArcGIS and Matlab, and can successfully duplicate a real road network for simulation in PEASM, and is combined with traffic activity (from California Air Resources Board for this work) and 1x1 km meteorology from the WRF model. Also presented are preliminary results from the size-resolved aerosol model. PEASM includes two options, a simple particle physics module with sectional treatment of a single non-volatile aerosol species, and a fully featured module that explicitly resolves aerosol mixing state and performs comprehensive aerosol thermodynamics and gas-particle partitioning calculations (using PartMC-MOSAIC developed by Riemer and Zaveri).

2009-A-319-ISES

Wintertime Spatial And Temporal Variability In Urban Combustion-related Pollutants: The New York City Community Air Survey

J. E. Clougherty,1 Z. Ross,2 S. Johnson,1 I. Kheirbek,1 H. Eisl,3 J. E. Gorczynski,3 S. Markowitz,3 T. Matte1; 1New York City Department of Health, New York, NY, 2ZevRoss Spatial Analysis, Ithaca, NY, 3City University of New York Queens College, New York, NY

Introduction Most land-use regression (LUR) studies of intra-urban air pollution variability have focused on gaseous species (e.g., nitrogen dioxide (NO2)) easily monitored in many locations simultaneously. Few have examined multiple pollutants, particle constituents, or year-round variation. Methods The NYC Community Air Survey (NYCCAS) is measuring multiple pollutants year-round at 150 locations throughout five boroughs. We selected 120 sites through stratified

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random sampling, and 30 purposeful locations of interest. Once per site each season, we collect two-week integrated fine particles (PM2.5) and constituents, elemental carbon (EC), nitrous oxides (NOx), sulfur dioxide (SO2) (winter), and ozone (O3) (summer). One site per borough is sampled every session for temporal variability. To minimize spatio-temporal confounding, we randomized sites across time; sites are sampled every two to eight sessions. We are developing LUR models examining spatial variability in multiple pollutants, within and across seasons, using GIS source indicators (e.g., traffic, buildings density) and meteorology. Results will describe intra-urban variation in ambient concentrations, identify sources and site characteristics (e.g., built topography) contributing to intra-urban variation, and provide guidance for NYC environmental policy. Results Preliminary first season (winter) data displays reproducibility in co-located NO(x) (R2 >= 0.95), and validity against co-located regulatory monitors (R2 = 0.89, 0.91, and 0.85 for NO2, SO2, and PM2.5). NO(x) species were highly correlated with each other (r >= 0.83) and with PM2.5 (r for NO2-PM2.5 = 0.84). SO2 correlates better with PM2.5 (r = 0.64) than NO(x) (r >= 0.42). Preliminary analyses indicate that NO(x) and PM2.5 correlated with traffic and building density (r > 0.25-0.53); SO2 correlates with buildings density (r >= 0.40) but not traffic. Conclusion Preliminary findings demonstrate strong variability and reproducibility in wintertime data, and associations with hypothesized sources. LUR models, to be developed in coming months, will explain additional variability in multiple pollutants and particle constituents.

2009-A-301-ISES

Incorporating Population Exposure Estimates In An Integrated Decision Support System For Air Quality Management

M. Loh; National Institute for Health and Welfare (THL), Kuopio, Finland

Air pollution reduction strategies should be considered on a European level to account for long-range transport. Existing health impact assessments (e.g. CAFÉ) have been based on ambient concentrations rather than population exposures. Using exposures is beneficial because it gives 1) a more realistic depiction of the amount of pollutant people potentially breathe in, and 2) expands the range of policy options that could be explored by incorporating people’s behaviour patterns or other micro-environmental characteristics that modify exposure to ambient source pollution. This study builds upon previous European scale assessments by incorporating an exposure module to the EcoSense model, which has been developed to assess health impacts from classical air pollutants at various spatial scales. The module is currently geared towards fine particles, but could be adjusted for other pollutants. The module includes distributions of exposure scaling factors (ESF) for several subpopulations in each country. Using Monte Carlo methods, distributions of the fractions of time spent in

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different micro-environments were multiplied by distributions of fine particle infiltration factors from outdoor to indoor and summed to produce the ESF. The ESFs were multiplied by the ambient air concentration levels to yield the exposure distribution in the population. EcoSense applies the ESFs to ambient concentration levels and the population subgroups in each EMEP grid cell (50 x 50 km²) within Europe. Preliminary estimates indicate higher ESFs for Southern countries. Individual exposure estimates show that men generally have higher exposures than women and. differences between countries are higher than between population subgroups. Average exposure to ambient PM2.5 ranged from 1.30 µg/m3 for women aged 65+ in Norway to 10.06 µg/m3 for men aged 65+ in Belgium. The ESF method provides a means of improving estimation of existing health impacts models for outdoor source air pollution and exploring a wider range of exposure reduction policies.

2009-A-324-ISES

The Changes Of Heavy Metal Components In Ambient Particle During The Sand-dust Weather In China

X. Pan, M. Fang, Q. Wang; Peking University School of Public Health, Beijing, China

Objective: To explore the changes of some metal components of ambient PM10 particle during sand-dust weather periods in Inner Mongolia of China and to analyze the relationship between the levels of Pulmonary Expiratory Flow Rate (PEFR) in the school children and the concentrations of certain heavy metal components within the ambient PM10 particles during the sand-dust weather. Method: Baotou city of Inner Mongolia was selected as our study field. The PEFR values of over 100 elementary school students was continually measured by themselves for 40 days in the spring seasons, the mass concentration of PM10 particle and some metal components in the particles were sampled and measured, the daily concentrations of CO, NO2 and SO2 in air and the related weather data were also collected. Statistic software SPSS 13.0 was used to conduct the t-test, ANOVA and Spearman correlation analysis. Result: 1. 17 sand-dust weather days were observed during two-year study period, and the daily concentrations of air PM10 is significantly higher in the sand-dust weather than in non-sand dust weather (p<0.001)). 2,The concentration of several elements were not significantly change during ordinary dust weather(p>0.05), and during heavy sand-dust weather, the daily average concentrations of Hg, K, Ca, Na and Mg were significantly increased (p<0.001).3,The relative contents of Pb, Cr, Cd, Hg, Na and Mg in PM10 showed a decreasing tendency during ordinary sand-dust weather, and their relative contents kept on declining as the concentration of PM10 increased. Conclusion: The relative contents of Pb, Cr, Cd, Hg, Na and Mg in air PM10 showed a decreasing tendency while the concentration of PM10 the dust weather were significantly increased during the sand-dust weather.

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2009-A-331-ISES

Levels, Composition And Sources Of Particles In Kuwait

P. Koutrakis,1 K. W. Brown,1 M. Al-Olayan,1 W. Bouhamra2; 1Harvard School of Public Health, Boston, MA, 2Kuwait University, Kuwait City, Kuwait

Kuwait, a desert country located on the Persian Gulf, has a large petroleum industry with associated industrial and urban land uses. To assess levels of particulate matter (PM) and PM components a detailed characterization study was conducted at three sites over 18 months in 2004-2005. Two sites were in urban areas (central and southern) and one in a remote desert location (northern). PM2.5 comprised 40-50% of PM10 measured at all of the sites, and arithmetic mean PM2.5 concentrations varied from 31 to 38 μg/m3 at the three sites. Fine particle nitrate, sulfate, elemental carbon (EC), organic carbon (OC) and elements were also measured at the three sites. All samples were collected using a polyurethane foam impaction surface in a modified Chemcombs sampler allowing for measurement in very high concentrations, as during dust storms. EC, OC and most of the elements were significantly higher at the urbanized sites, indicating significant pollutant contributions from local mobile and stationary sources. To better assess potential source profiles for PM2.5 in Kuwait, we conducted a source apportionment analysis, using factor analysis. Three factors were identified corresponding to three source types: a) soil (mostly desert dust) comprising Si, Al, Fe, and Ca; b) long range transported pollution comprising mostly ammonium sulfate; and c) local traffic comprising EC, Pb, Cu and Zn. Results suggest that each of the sources contributed approximately one-third of measured PM2.5. The factors account for most of the observed PM2.5 mass. In addition, elemental data were regressed on several meteorological variables. Daily average wind speed was significantly positively associated with Si and inversely associated with S and EC. These results indicate that higher wind speeds increased ambient levels of Si (due to soil re-suspension), but reduced ambient sulfur and elemental carbon that originate from local sources.

2009-A-416-ISES

Modeling Personal Exposures To Fine Particulate Matter Mass, Elemental And Organic Carbon, And Nitrogen Dioxide In A Panel Of Southern California School Children With Asthma

H. C. Phuleria,1 R. Ducret-Stich,1 T. Tjoa,2 J. Wu,2 R. J. Delfino,2 L. J. S. Liu1; 1University of Basel, Basel, Switzerland, 2University of California, Irvine, CA

Recent studies have shown associations between adverse health effects and measured or modeled estimates of ambient air pollutant concentrations of traffic origin. However, most studies do not take into account activity patterns and exposure in different microenvironments which may under/over estimate these effects. Personal exposure of 63

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children with asthma, ages 9-18 yr, was assessed for 10 days in 2003/2004 in two different areas of Southern California. Each child carried an active personal DataRAM to measure continuous PM2.5 (particulate matter <2.5 µm) and 24-hr PM2.5, EC (elemental carbon), OC (organic carbon) and NO2 (nitrogen dioxide) and completed an electronic time-place-activity diary every two waking hours. One of the 4 children’s homes was also monitored for 24-hr PM2.5, EC and OC using Harvard Impactors. Identical measurements were also taken daily at the respective central sites. Different personal exposure models were developed based on available data. Models based on central site concentrations, geographic information system and traffic variables performed very well for PM2.5 (R2=0.72) and EC (R2=0.60) and reasonably for OC (R2=0.38) and NO2 (R2=0.34). Adding home characteristics data improved the model performance for all the pollutants. The significant predictors included “gasstove pilot light on”, “garage attached to home”, “gasstove at home” and “homes with smoker” for different pollutants. Total personal exposure models, based on time-weighted individual microenvironmental exposures, performed similarly to the previous models for PM2.5 (R2=0.66) but not for EC (R2=0.32) and OC (R2= 0.05). For OC, indoor modeling errors for homes without measurements seriously weakened the total personal exposure estimates. We conclude that for EC, OC and NO2 which are predominantly affected by local sources, models based on central site measurements may not be adequate. Models of total personal exposure, however, require robust indoor exposure estimates. More specific research and additional studies are needed in this direction.

2009-A-435-ISES

Fine Particulate Matter Concentrations In Low- And Middle-income Neighborhoods In Bangalore, India

A. F. Both, J. D. Marshall; University of Minnesota, Minneapolis, MN

We measured outdoor fine particulate matter (PM2.5) concentrations in a low- and a nearby middle-income neighborhood in Bangalore, India. Each neighborhood included one sampling location near (200m) a major roadway. One-minute average concentrations were recorded for 168 days during September 2008 - May 2009 using a nephelometer. We also measured wind speed and direction and concentration as a function of distance from roadway. A moving-average subtraction method (Watson and Chow, 2001) was applied to the fixed-site data to distinguish local- (~100-1000m), neighborhood- (~1-5km) and urban-scale (~5-50km) sources of PM2.5. Average concentrations are 10-60% higher in the low- than in the middle-income neighborhood. Median concentrations (units: microgram m-3) near and not-near the roadway are 72 and 81, respectively, in the low-income neighborhood and 68 and 54, respectively, in the middle-income neighborhood. These concentrations exceed long-term US EPA and WHO standards (15 and 10, respectively). The moving-average method indicates that local and neighborhood sources typically contribute 40% (20%) of the total concentration in the low-income (middle-income) neighborhood. Our results indicate significant non-traffic PM2.5 sources in the low-income neighborhood but not the middle-income neighborhood. Neither

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neighborhood exhibited the expected stereotypical decline in concentration at increasing distance from the roadway. Landscaping (e.g., walls, trees) in the middle-income neighborhood likely mitigates local traffic pollution impacts by altering local airflow patterns; as a result, most pollution in that neighborhood is urban-scale. In contrast, the low-income neighborhood likely experiences significant PM2.5 emissions inside the neighborhood, leading to more pollution being local/neighborhood and reducing the local importance of vehicle emissions. We conclude that the moving-average subtraction method yields meaningfully information about spatial variability. Stereotypical declines in total concentration away from a roadway may not hold in many important contexts, including urban slums, owing to significant in-neighborhood emissions and local wind-flow barriers.