It is the first standard for chromium-6, also known as hexavalent chromium, in the nation.
Acknowledging that there was more to the decision than just public health, CDPH Director Dr. Ron Chapman said, “The drinking water standard for hexavalent chromium of 10 parts per billion will protect public health while taking into consideration economic and technical feasibility as required by law.”
The CDPH calculated that it would cost public water treatment systems $156 million to implement it.
Environmentalists took issue with multiple aspects of Chapman’s statement. “A 10-parts-per-billion standard is certainly better than nothing,” said Environmental Working Group Director Renee Sharp. “But when you know that the standard is not truly protecting the public from cancer and other health impacts, it doesn't feel like a victory.”
Natural Resources Defense Council attorney Avinash Kar said, “The department both inflated water treatment costs and underestimated the benefits of a stronger standard to justify its proposal. Politics and special interests shouldn’t be able to interfere with and delay the process of setting public health standards for dangerous chemicals in drinking water.”
The decision affirms a proposal by the department last August to allow 10 parts per billion (ppb) of the chemical made famous by the movie Erin Brockovich in 2000, although CalEPA suggested a goal in 2011 of 0.02 ppb. The department received 18,000 comments on the proposed regulation, which it will now send to the Office of Administrative Law (OAL) for final procedural approval.
There is some evidence that chromium-6 can damage DNA. Other studies have linked it to male reproductive harm, liver toxicity and blood disorders. The chemical is on California’s Prop. 65 list of substances known to cause cancer and reproductive harm. It has long been considered dangerous if inhaled and in 2007 the federal government determined that it’s not OK to eat it either.
Chromium-6 was found in the drinking water of at least 500 California communities in 51 of the state’s 58 counties between 2000 and 2004. Trace amounts are known to cause cancer but the state refused for years to set a standard until CalEPA made its recommendation.
Erin Brockovich chronicled the experience of residents in the small town of Hinckley, California, who were exposed to chromium-6 when Pacific Gas & Electric (PG&E) used it to prevent rust in water towers. The water seeped into the groundwater and caused health problems that included bronchitis, asthma and lung cancer. PG&E settled with Hinckley residents in 1996 for $333 million.
The regulation, which will be reviewed every five years, is slated to take effect on July 1.