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OSHA’s Approach to Nanotechnology: Developing a Searchable "Health Effects Matrix" Database for Nanomaterials Utilizing Existing Published Data

Janet Carter

Sr. Health ScientistDepartment of LaborOccupational Safety & Health AdministrationDirectorate of Standards and Guidance

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Presentation Outline

• Brief overview of OSHA perspective on nanotechnology

• Highlights of OSHA activity

• Specifics on “Health Effects” matrix

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OSHA’s Mission

… “assure safe and healthful working conditions for working men and women”…

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Nanomaterials – highly diverse in form, structure, chemistry

4Source: Maynard et al., 20053

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Many Applications for Nanotechnology

• Every day uses such as sunscreens

• Electronic and Information Technologies

• Sustainable Energy Applications

• Environmental Remediation

• Nanobiosystems, Medical, and Health Applications

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OSHA’s Interest in Nanomaterials

• Various studies suggest some nanomaterials may be toxic to workers– Effects may be dependent on size, crystalline

structure, solubility, shape, chemical form, other characteristics

– Not necessarily relatable to macro-scale material of same chemical composition

– Many unknowns remain

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What is known about nanomaterials

• Small, insoluble particles may be more toxic than large particles on a mass basis

• Small particles may distribute beyond portal of entry

• Distributed particles may have different organ distribution and clearance than soluble materials

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What is Not Known• How to predict potential for novel mechanisms of

toxicity

• How to predict extra-pulmonary particle distribution, clearance based on physico/chemical properties

• High to low dose extrapolation methods

• Sensitive subpopulations-range of sensitivity

• Consequences of distribution and long term residence in brain, liver, spleen, bone marrow, including data on bench-mark compounds or screening methods for hazard ranking

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Not all nanomaterials are alike

Source: Maynard et al., 2005

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OSHA’s conundrum

• Small agency

• Small budget in comparison to other Federal agencies with nano programs

• Scarce and/or inconsistent information– Cannot treat all nanomaterials as same

• Proactive on safety and health issues without hindering or stifling innovation or job-growth

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OSHA’s Objective for Nanotechnology

• Protect workers

• Promote safe sustainable stewardship of nanotechnology

• Promote collaboration between Federal Partners, Industry and Labor

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OSHA’s Approach to Nanotechnology

• Utilize existing framework

• Work through National Nanotechnology Initiative (NNI)

• Form collaborations with Federal agencies, NGOs, Industry, Labor organizations

• Develop Agency specific programs

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OSHA Program Activities

• Develop guidance materials and information for workers and businesses to promote sustainable occupational practices

• Develop bibliographic database of peer-reviewed EHS publications - “Health Effects Matrix”– Possible hazard determination guidance – Possible SAR development

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Nanomaterials Health Effects Matrix• Focus on existing published data• Searchable and sortable format

– Highlight similar effects

• Develop SAR for nano?• Develop hazard determination criteria

– Safety data to be included

• Information to be publically available– Venue not determined yet

• Publish in peer-review journal• Public access on website

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Literature Search Findings

• To date:– Over 700,000 Nanotechnology publications (according to

Web of Science)– Close to 32,000 studies have been published and available

through NLM/PubMed • More than 3300 are review articles

– More than 4000 studies of those on nanomaterial/nanoparticle toxicity

• More than 2100 studies focused on human toxicity– Approximately half studies conducted using in vitro systems– More than 20 different broad categories of materials tested– More than 500 of these publications are review

• Approximately 1100 studies have been identified as having usable information for our database

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Distribution by Study Compounds

0

50

100

150

200

250

300

350 Al

CB

Chitosan

CNT

Dendrimers

Fullerenes

Gold

Polystyrene

Silica

Silver

QD

ZnO

TiO2

Zeolites

Nickel

Polymers

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Information Collection for Database

• Full reference information• Biological effect

– System/organism– Delivery system– Vehicle– Full test info– Species– Study duration– Dose –

• with corresponding biological response for each endpoint

– Quantitative – Qualitative

– Sample size– How was material dispersed

• agents or actions

• Materials– Chemical composition– Size

• Principle (mean)• Distribution• Agglomeration state

– Surface area– Structure – Solubility– Manufacturer, producer,

laboratory of nanomaterial– Contaminants– Other information

• Scans• Certificate of analysis• MSDS

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Example of Database Entry:

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Preliminary Findings

• Labor intensive process

• Iterative process

• Most EHS data generated from 1st generation nanoparticles and CNTs– Are a few exceptions

• R&D work on 3rd generation nanomaterials– Very early stage research for 3rd generation– 2nd generation near market stage

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Preliminary Conclusions

• Data is more usable than many critics say• Trends are emerging

– Able to make some preliminary determinations on apparent “inconsistencies” in the literature

• Highlights to need for more consistency in how research is conducted– Not unique to nanoresearch

• Can be used as tool to develop future research needs by systematically highlighting current gaps in research/knowledge

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Future Direction of Project

• Anticipate completely preliminary results by end of August 2012

• Possible publication by fall/winter (if accepted in journal)

• Update database utilizing new search criteria early 2013

• Share database to other communities after formal clearance

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