What’s In the Water?

The last time I wrote about hexavalent chromium, a toxic chemical known to cause myriad health problems, it was in a piece on soldiers who say they were exposed to it while guarding a water treatment facility in Iraq. But the chemical, made famous by Erin Brockovich, is also turning up in drinking water sources around the United States.

A recent report from the Environmental Working Group found the chemical in the tap water of 31 out of 35 cities it tested. This is a major issue, as exposure through drinking water has been linked to stomach and gastrointestinal cancers in both humans and animals. From the report:

The highest levels were in Norman, Okla.; Honolulu, Hawaii; and Riverside, Calif. In all, water samples from 25 cities contained the toxic metal at concentrations above the safe maximum recently proposed by California regulators.

The National Toxicology Program has concluded that hexavalent chromium (also called chromium-6) in drinking water shows “clear evidence of carcinogenic activity” in laboratory animals, increasing the risk of gastrointestinal tumors. In September 2010, a draft toxicological review by the U.S. Environmental Protection Agency (EPA) similarly found that hexavalent chromium in tap water is “likely to be carcinogenic to humans.”

The EPA responded quickly to the new report; Administrator Lisa Jackson met with a group of 10 senators about the issue and released a statement outlining the EPA’s next steps:

Today, I am announcing a series of actions that the EPA will take over the coming days to address chromium-6 in our drinking water. It is clear that the first step is to understand the prevalence of this problem. While the EWG study was informative, it only provided a snapshot in time. EPA will work with local and state officials to get a better picture of exactly how widespread this problem is. In the meantime, EPA will issue guidance to all water systems in the country to help them develop monitoring and sampling programs specifically for chromium-6. We will also offer significant technical assistance to the communities cited in the EWG report with the highest levels of chromium-6 to help ensure they quickly develop an effective chromium-6 specific monitoring program.

This is good news, but could take some time to actually equate to meaningful action. In the meantime, what can people do about the chemical? AlterNet put together a helpful list of questions and answers, including how one can find information on the levels of the chemical in their local water system and what to do if your water is contaminated.


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