Hexavalent Chromium in California drinking water
The National Resources Defense Council recently announced a great legal victory, a court order forcing the state of California to set a drinking water standard for Hexavalent Chromium [Cr(VI)] by the end of this month. Many will be watching with great interest to see what level the state chooses. Nationally – EPA is at the beginning of a three year process which will assess for the first time, what the level of this contaminant is in the drinking water provided to most of the rest of America.
There is one aspect of the nearly two decades of study that will go into the California decision that I still find quite intriguing. It turns out that there are many rural areas in the state where Cr(VI) occurs naturally in the groundwater, at concentrations near where a feasible standard might be. Many of these communities must sit right next to communities served by surface water systems that are free from Cr(VI). This seems like a perfect set up for a powerful epidemiology study, that could provide a great reference to support the standard. Yet – no such study seems to be underway, and it seem unlikely that one could be completed in time to inform the decision making process.