why we should be worried about our water lily clark envr 230 november 6, 2007
TRANSCRIPT
Why we should be worried about our water
Lily ClarkENVR 230November 6, 2007
Drinking Water in the U.S.: OverviewOverall, water quality has improved over the last
15 years, according to a report done by the Natural Resources Defense Council (NRDC)
Quality of tap water varies greatly from city to cityMost cities have good or mediocre water quality
NRDC estimates that 50 million Americans drink water that is below the standards for water quality set by the EPA (1996)
CDC estimates that half of the country’s water treatment systems fail to remove the parasite that killed 100 people in Milwaukee in 1993 (1996)
Contaminants enter water in many ways, such as through runoff from sewage systems, runoff from roads and farms, and dumping of industrial waste
RegulationEPA has National Primary Drinking Water Regulations
(NPDWRs) to enforce standards for public water systems
Clean Water Act (CWA) of 1972 and Safe Drinking Water Act (SDWA) of 1974 passed “to restore and maintain the chemical, physical and biological integrity of the nation’s waters”Safe Drinking Water Act Amendments of 1996
introduced new prevention approaches, changes in regulation, increased funding to state and local governments and improved consumer information
CDC performs and funds research and helps disseminate information regarding safe drinking water
Maximum Contaminant Levels (MCLs)Microorganisms
CryptosporidiumGiardiaLegionellaColiforms (including E. coli)TurbidityEnteric viruses
Disinfectants – chlorine and chloraminesDisinfection by-products – chlorite, haloacetic acids,
trihalomethanesInorganic chemicals – arsenic, cyanide, fluoride, lead,
mercuryOrganic chemicals – atrazine, carbon tetrachloride, TCDD,
PCBsRadionuclides
Problems with RegulationReport by the General Accounting Office in 1993
found that “most state inspection programs to ensure the safety of public water supplies are a shambles”State public health departments responsible for
monitoring and reporting to the EPA on water qualityHowever, many state inspection programs are under
funded and are thus unable to test the water every three years, as recommended by the EPA
Deficiencies often went unidentified and uncorrected due to bad record-keeping
Less than half of the inspectors nationwide had been formally trained
Lapse in regulation seen in DC lead contamination and the disease outbreak in Milwaukee
Health EffectsLead
Permanent brain damage and decreased intellectual ability in infants and children
Trihalomethanes and haloacetic acidsCancer and reproductive problems, including
miscarriageAll possible health effects especially dangerous
for those with a compromised immune systemPregnant women, infants, children, elderly,
HIV/AIDS patients, chemotherapy and cancer patients
Health Effects of Waterborne PathogensEspecially dangerous for the immuno-compromised
(HIV/AIDS, the elderly, children, chemo patients)Cause diarrhea and acute gastrointestinal illness
(AGI)Currently estimated 4.26 – 11.69 million cases of
AGI annuallyDue to drinking water from community drinking
water systems supplied by surface and groundwater sources
However, most of the microbes that have caused outbreaks of waterborne diarrheal illnesses in the U.S. and their sources are unidentified
Threats to Water QualityReliance on pipes that are 100 years old, on
averageProblems with breakageLeach contaminants and allow bacteria to breed
Reliance on outdated water treatment techniques
Regulatory efforts by the Bush administrationWeaken regulation on source watersStall the creation of new standards for
contaminantsCut funding and environmental programs
How the Bush Administration’s Policies Threaten Our Drinking WaterBush administration policies in 2003 supported reducing
the protection of our water sources and our drinking water
Specifically, proposed scalebacks would have removed protection for headwaters, wetlands, seasonal streams and other water sourcesPolicy would exempt protections on “isolated” watersThese exemptions would have affected directly the drinking
water sources for 15 U.S. cities, including Atlanta, Baltimore, D.C. and Seattle
Policy rejected in 2006In 2006, the Bush administration declared that federal
workers would not be protected under whistleblower protection for reporting “water enforcement breakdowns, manipulations of science, or cleanup failures”Threatens the integrity of the CWA and SDWA by removing
protection from federal employees who attempt to uncover and report honestly the state of our water quality
What’s On Tap: Grading Drinking Water in U.S. CitiesThe Natural Resources Defense Council
issued a 2003 report on the quality of drinking water in 19 states
Process of Water TreatmentCoagulation – addition of aluminum sulfate to make large
particles of solids stick togetherPerchlorination (optional) – addition of chlorine or other
oxidant to start disinfection and oxidation of chemicals If added at this early stage, can greatly increase levels of by-
productsSedimentation – water mixed and left to sit to allow
coagulant to take effectFiltration – run water through filters of sand or coal to
remove smaller particles (unable to remove arsenic, pesticides and other chemicals)
Primary chemical disinfection – usually chlorine gas or liquid
Corrosion inhibitor – lime or zinc orthophosphate to inhibit ability of water to corrode city and household piping
Fluoride and secondary disinfection – second dose of infectant to prevent recontamination
Waterborne PathogensVegetative bacteria and other microorganisms are
killed by disinfection process of water treatmentCryptosporidium and Giardia are relatively resistant to
disinfection processMany waterborne parasites are resistant to
chlorinationFiltration removes these parasites, however many
treatment facilities have broken and failing filtration systems
Acute gastroenteritis illness (AGI) is most common health problem associated with consumption of water contaminated with microbesAssociations between water turbidity and AGI have
been found in citywide studies performed in Milwaukee and Philadelphia
AGI rates in the US can be used to estimate the risk of infectious, waterborne diseases
Waterborne Disease Outbreaks (WBDOs)Outbreak statistics do not accurately reflect the incidences
of waterborne illness due to endemic contaminationThere is no surveillance system to report the incidences of
endemic waterborne illness, specifically AGI, in the USReported occurrences of WBDOs are only a fraction of the
actual occurrences of AGI because endemic illnesses are not included
WBDO statistics have been recorded since the 1920s through local, state and national public health departments
Useful to identify risks of disease associated with source waters, public water systems and treatments
Also provide information about the important waterborne pathogens and adequacy of contamination regulations
Disease OutbreaksWaterborne pathogens are increasing as a cause of
waterborne disease outbreaks in the U.S.Between 1991 and 2002
403,000 people got sick4,400 were hospitalized50 died
Mortality associated with WBDOs decreased from 1920 to 1990 but has risen in the last 12 years
The percentage of WBDOs associated with contaminants in the public water systems have increased since 1991
Outbreak tracking does not take into account rates of endemic waterborne diseases, which can be caused by the same pathogens
Taken from Craun et al. “Waterborne outbreaks reported in the United States.” Journal of Water and Health. 2006.
Etiology of waterborne outbreaks reported in the U.S., 1991 – 2002Etiological agent Outbreaks Cases
AGI 77 16,036
Chemical 33 577
Giardia 25 2,283
Cryptosporidium 15 408,371
Norovirus 12 3,361
E. coli O157:H7 11 288
Shigella 9 663
Campylobacter jejuni 7 360
Legionella 6 80
Salmonella 3 833
V. cholerae 2 114
Hepatitis A 2 56
Naegleria fowleri 1 2
Plesiomonas shigelloides 1 60
Campylobacter and Yersinia 1 12
E. coli O157:H7 & Campylobacter
1 781
Unidentified SRSV 1 70
Total 207 433,947Taken from M. F. Craun et al. “Waterborne outbreaks reported in the United States.” Journal of Water and Health. 04.Suppl 2. 2006.
Milwaukee, 1993400,000 people got sick and 100 died from
contaminated waterCryptosporidium was the parasite found in
the waterCaused death mostly in immuno-
compromised populations, specifically those with HIV/AIDS
New York, 19991,000 people got sick at a county fair in
upstate New YorkThe water was contaminated with a virulent
strain of E. coliResulted in the death of one elderly man and
one 3-year old girl
New York, 2005Nearly 750 people got sick from a
contaminated play area in a water park The water was found to be contaminated with
cryptosporidiumThe tank from which the water park drew its
water had a chlorination and a filtration system
U.S. Public Interest Research Group 2005 Report on CWA Compliance3600, or 57%, of the nation’s water treatment
facilities exceeded limits set by the CWA at least once in 2005Noncompliant facilities reported 24,400 cases of
exceeding CWA permitsIndicates that facilities are exceeding their permits
more than once, and for more than one pollutant628 facilities exceeded their permit limits for at
least half of the monthly reporting periods in 2005On average, noncompliant facilities exceeded
permit limits by four times the allowed amountOn 1800 occasions, facilities reported exceeding
the limits by at least six-fold
Recommended Actions by the Natural Resources Defense CouncilInvestment in upgrading water systems
Pipe breaksAllow in bacteria and contaminantsEstimated $500 billion over the next two decades to
ensure the safety of drinking water nationwideUpgrading of water treatment techniques
Currently use same basic water treatment technologies from before WWI
New technologies available – ozone, UV light treatment, membrane treatment, granulated activated carbon
Use a combination of two or more to maximize efficiency and minimize by-products of treatment
Strengthen and enforce existing health standards and create new standards for unregulated contaminants
Sources EPA
Office of Water: http://www.epa.gov/OW/ Health and Environmental Effects Research Laboratory:
http://www.epa.gov/nheerl/articles/2006/waterborne_disease.html “Clinton Administration works to help protect the public health from recent infectious disease outbreaks.”:
http://yosemite.epa.gov/opa/admpress.nsf/a21708abb48b5a9785257359003f0231/52a4c3f2c4d50b31852567ee00661941!OpenDocument
CDC Healthy Drinking Water: http://www.cdc.gov/Ncidod/dpd/healthywater/index.htm “Surveillance for Waterborne-Disease Outbreaks --- United States, 1999-2000”:
http://www.cdc.gov/MMWR/preview/mmwrhtml/ss5108a1.htm Natural Resources Defense Council
“Study Finds Safety of Drinking Water in U.S. Cities at Risk”: http://www.nrdc.org/water/drinking/uscities.asp
“What’s on Tap? Grading Drinking Water in U.S. Cities”: http://www.nrdc.org/water/drinking/uscities/contents.asp
“Limiting Clean Water Act Protection Could Contaminate Drinking Water”: http://www.nrdc.org/media/pressReleases/030611a.asp
“Clean Water at Risk”: http://www.nrdc.org/water/pollution/cwa30/contents.asp CNN
“Milwaukee learned its water lesson, but many other cities haven’t”: http://www.cnn.com/HEALTH/9609/02/nfm/water.quality/
“1,800 infected; water park blamed”: http://www.cnn.com/2005/US/08/19/water.illness/index.html New York Times
“Outbreak of Disease in Milwaukee Undercuts Confidence in Water”: http://query.nytimes.com/gst/fullpage.html?res=9F0CE6D9143EF933A15757C0A965958260
“Nearly 750 Are Sickened at State Park”: http://www.nytimes.com/2005/08/19/nyregion/19sick.html New York Department of Health
http://www.health.state.ny.us/press/releases/2000/ecoli.htm US PIRG
“Troubled Waters: An analysis of 2005 Clean Water Act compliance”: http://static.uspirg.org/reports.asp?id2=35946
Stormwater Authority: http://www.stormwaterauthority.org/library/view_article.aspx?id=633 Earthjustice:
http://www.earthjustice.org/our_work/policy/2004/bush_administration_launches_effort_to_dismantle_clean_water_act.html