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Carcinogen Found in Drinking Water


Cue Erin Brockovich and the bottled water (kidding!)... the probable carcinogen hexavalent chromium was found in the drinking water of 31 United States cities. Yes, it’s the same chemical that had Brockovich sneaking onto power plants and crawling into sewers to help hundreds of people.

The Environmental Working Group recently released the first public nationwide analysis of hexavalent chromium in drinking water. It comes on the heels of the Environmental Protection Agency’s consideration to set a limit for hexavalent chromium in tap water.

Hexavalent chromium (aka chromium-6) was a common chemical used in manufacturing plants until the early 1990s. However, it’s still used in chrome plating, plastic and dye plants and can leach into groundwater from natural ores. In 2008 the National Institutes of Health deemed the chemical a possible carcinogen. As of now, the federal government restricts the amount of “total chromium.” However, that includes both trivalent chromium (a mineral humans need to metabolize glucose) and the cancer-causing hexavalent chromium.

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From the Organic Authority Files

The new study found the carcinogen in 31 out of the 35 city samples. Of that, 25 cities exceeded the safe level 0.06 parts per billion. The top five chromium-contaminated cities are Norman, OK (12.9 ppb), Honolulu, HI (2.00 ppb), Riverside, CA (1.69 ppb), Madison, WI (1.58 ppb), and San Jose, CA (1.34 ppb). For a complete list of contaminated cities, visit the EWG’s report.

To curb the leaching of this chemical, the EPA just released a plan to help water facilities better monitor for hexavalent chromium. “Local water utilities will now be able to better determine if their water carries potentially troubling levels of this carcinogen and get that information out to the public quickly,” said Environmental Working Group senior vice president for research Jane Houlihan. “This comprehensive plan and the speed with which it was produced is proof the federal government can act decisively to address public health issues people are concerned about.”

Find out more about the EPA’s plan for monitoring hexavalent chromium.

image: Reiner Schubert

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