Chromium-6 in U.S. Tap Water
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Chromium-6 in U.S. Tap Water Rebecca Sutton, PhD EWG Senior Scientist http://www.ewg.org/chromium6-in-tap-water http://www.ewg.org/chromium6-in-tap-water Contents Background i. Executive Summary. 4 ii. Study Findings . 8 iii. Industry Tactics. .11 iv. Government Failings. .15 v. Progress in California. 17 vi. Methodology. .19 vii. References. 21 This PDF is QR Mobile Interactive Scan this QR code with your web and camera featured smart phone and be taken to the online report for Cancer Causing Chromium 6 in U.S. Tap Water. Download QR Reader for your Smartphone: www.i-nigma.mobi Chromium-6 Is Widespread in US Tap Water: Environmental Working Group 2 Acknowledgments Principal Author: Rebecca Sutton, PhD Editors: Jane Houlihan, Renee Sharp & Nils Bruzelius Databases & Mapping: Chris Campbell & Sean Gray Web Design: Dean Clark This report was made possible by the support of the John Merck Fund, the Johnson Family Foundation, the Park Foundation and the Turner Foundation. EWG thanks Erin Brockovich and Bob Bowcock for their continued efforts to protect public health, and Max Costa (New York University School of Medicine) for his review of our report. Interns Jacob Booher, Marisa Evanouski, Samara Geller and Kimi Schell made significant contributions to this research. We also thank EWG contacts nationwide who made this study possible by volunteering to collect water samples for analysis. Chromium-6 Is Widespread in US Tap Water: Environmental Working Group 3 http://www.ewg.org/chromium6-in-tap-water Executive Summary Tap water from 31 of 35 U.S. cities tested contains hexavalent chromium (or chromium-6), the carci- nogenic “Erin Brockovich chemical,” according to laboratory tests commissioned by Environmental Work- ing Group (EWG). The highest levels were detected in Norman, Okla.; Honolulu, Hawaii; and Riverside,i Calif. Despite mounting evidence of the contaminant’s toxic effects, including a U.S. Environmental Protec- tion Agency (EPA) draft toxicological review that classifies it as “likely to be carcinogenic to humans” when consumed in drinking water, the agency has not set a legal limit for chromium-6 in tap water and does not require water utilities to test for it. Hexavalent .02 chromium is commonly discharged from steel and .18 pulp mills as well as metal-plating and leather-tanning .15 facilities. It can also pollute water through erosion of soil and rock. .1 The National Toxicology Program has found that hexavalent chromium in drinking water shows clear evidence of carcinogenic activity in laboratory ani- .05 .06 mals, increasing the risk of otherwise rare gastrointes- tinal tumors (NTP 2007, 2008). In response to this Chromium-6 in tap water (parts per billion) .0 study and others, California officials last year proposed Average Proposed setting a public health goal for chromium-6 in drink- chromium-6 safe limit** level in EWG ing water of 0.06 parts per billion (ppb). This is the testing* first step toward establishing a statewide enforceable *Geometric average based on level of chromium-6 measured in 35 U.S. cities and a statistical estimate for the four cities limit (OEHHA 2009). where no chromium-6 was detected. The lowest level detect- able by these tests is 0.02 ppb. For the purpose of calculating Levels of the carcinogen in 25 cities tested by the nationwide average, the concentration of chromium-6 in EWG were higher than California’s proposed public these four cities was assumed to be 0.01 ppb, or half of the lowest detectable level. health goal. Tap water from Norman, Okla. (popula- **“Proposed safe limit” is California EPA’s proposed public tion 90,000) contained more than 200 times Califor- health goal (OEHHA 2009). nia’s proposed safe limit. Source: EWG-commissioned testing for hexavalent chromium in tap water from 35 cities. Chromium-6 Is Widespread in US Tap Water: Environmental Working Group 4 Top Five Chromium-contaminated Cities Tested by EWG Hexavalent Chromium Contamination City City Population Level in Tap Water Norman, Oklahoma 89,952 12.9 ppb Honolulu, Hawaii 661,004 2.00 ppb Riverside, California 280,832 1.69 ppb Madison, Wisconsin 200,814 1.58 ppb San Jose, California 979,000 1.34 ppb Millions of Americans drink chromium-contaminated water EWG’s investigation is the broadest publicly available survey of hexavalent chromium to date. The 31 cities with chromium-polluted tap water draw from utilities that collectively serve more than 26 million people. In California, the only state that requires testing for hexavalent chromium, water utilities have de- tected the compound in tap water supplied to more than 31 million people, according to an EWG analysis of data from the state water agency (EWG 2009). EWG’s tests provide a one-time snapshot of chromium-6 levels in 35 cities. But chromium pollution is a continuous, ongoing problem, as shown by the annual water quality reports that utilities must produce under federal law. Over the years, nearly all of the 35 cities tested by EWG regularly report finding chromium (in the form of total chromium) in their water despite using far less sensitive testing methods than those used by EWG. The total number of Americans drinking tap water contaminated with this compound is likely far higher than is indicated by EWG’s tests. At least 74 million people in nearly 7,000 communities drink tap water polluted with “total chromium,” which includes hexavalent and other forms of the metal, according to EWG’s 2009 analysis of water utility tests from 48,000 communities in 42 states (EWG 2009). The EPA has set a legal limit in tap water for total chromium of 100 ppb to protect against “allergic dermatitis” (skin irritation or reactions). Measures of total chromium include the essential mineral trivalent chromium, which regulates glucose metabolism, as well as the cancer-causing hexavalent form. Preliminary EWG-commissioned water tests found that in most cases, the majority of the total chromium in water was in the hexavalent form, yet the EPA’s legal limit for total chromium is 1,700 times higher than California’s proposed public health goal for hexavalent chromium. This disparity could indicate significant cancer risk for communities drinking chromium-tainted tap water. Chromium-6 Is Widespread in US Tap Water: Environmental Working Group 5 http://www.ewg.org/chromium6-in-tap-water The EPA’s new analysis of hexavalent chromium toxicity, released in draft form in September 2010 (EPA 2010a), cites significant cancer concerns linked to exposure to the contaminant in drinking water. It high- lights health effects documented in animal studies, including anemia and damage to the gastrointestinal tract, lymph nodes and liver. Industry deception delayed protections The plight of the cancer-stricken residents of Hinkley, Calif., who in 1996 won a $333 million settle- ment from Pacific Gas and Electric Co. for contaminating their tap water with hexavalent chromium, was the basis of the 2000 movie “Erin Brockovich,” starring Julia Roberts. Subsequently, a 2005 Wall Street Journal investigation and a separate EWG report based on court docu- ments and depositions from a similar lawsuit in Kettleman City, Calif. revealed that PG&E had hired consultants to publish a fraudulent analysis of cancer mortality in Chinese villagers exposed to hexavalent chromium, in an attempt to disprove the link between the chemical and cancer. The study was published in the respected Journal of Occupational and Environmental Medicine, and scientists and regulators — in- cluding the EPA — cited the fraudulent article in research and safety assessments. The journal retracted the paper in 2006 in response to EWG’s request for corrective action. California officials then conducted a rigorous re-assessment of the study data, finding a statistically sig- nificant increase in stomach cancer among the exposed. Their analysis is consistent with laboratory evidence from the National Toxicology Program and others showing that hexavalent chromium in tap water causes gastrointestinal tumors in multiple species. Industry has sought for more than six years to delay state-mandated regulation of hexavalent chromium in tap water in California. Aerospace giant Honeywell International Inc. and others have stalled the adop- tion of the advisory public health goal by pressing for additional external scientific peer review. California’s Department of Public Health can neither set nor enforce a mandatory tap water standard for hexavalent chromium until the goal is finalized. Recommendations At least 74 million Americans in 42 states drink chromium-polluted tap water, much of it likely in the form of cancer-causing hexavalent chromium. Given the scope of exposure and the magnitude of the po- tential risk, the EPA should move expeditiously to establish a legal limit for the chemical in tap water and require water utilities to test for it. Chromium-6 Is Widespread in US Tap Water: Environmental Working Group 6 The state of California must establish a strong standard for hexavalent chromium in tap water immedi- ately. A truly health-protective hexavalent chromium regulation will reduce the cancer risk for Californians and serve as a model for the nation. With an enforceable standard already six years past the statutory dead- line and the health of millions of Californians at stake, the state cannot move too quickly. Chromium-6 Is Widespread in US Tap Water: Environmental Working Group 7 http://www.ewg.org/chromium6-in-tap-water Study Findings Carcinogenic Erin Brockovich Chemical Found in Tap Water Across the U.S. Tests commissioned by the Environmental Working Group (EWG) detected carcinogenicii hexavalent chromium in 31 of 35 tap water samples — 89 percent — collected in cities across the country. EWG targeted a mix of large cities and some smaller ones where testing by local water utilities had previously de- tected potentially significant amounts of “total chromium.” This less specific measurement includes trivalent chromium, an essential mineral that regulates glucose metabolism, as well the cancer-causing hexavalent form, also called chromium-6.