Photo by lifeinthedistrict.

And you thought the biggest problem with D.C. water was the possible lead contamination. The Environmental Working Group will release a study Monday showing that out of 35 cities surveyed, 31 have hexavalent chromium in their tap water. You might have heard of hexavalent chromium, as you might remember Erin Brockovich, who sued the Pacific Gas & Electric in California when the possible carcinogen was found in Hinkley, CA’s water supply.

And yes, D.C. and Bethesda were a part of the national study: both tested positive for hexavalent chromium. While there is no national standard of acceptable levels of the possible carcinogen, both cities have levels above a rate California is proposing as acceptable. California’s proposed safe level is 0.06 parts per billion, D.C. and Bethesda each had levels of 0.19 parts per billion, 3 times the proposed standard.

Apparently California’s proposed standard is under scrunity. The American Chemistry Council says it is unrealistic because hexavalent chromium is naturally present in water at higher rates than the proposed standard.

So you probably saw the movie, but wondering what exactly the danger of the possible carcinogen is? Hexavalent chromium causes lung cancer when inhaled, but it also has caused cancer in laboratory animals when ingested. Fun.