MoreEWG report puts Hexavalent Chromium back in
national spotlight
On Monday, Dec. 20, 2010, the Environmental Working Group (EWG), an environmentalist organization most famous for its annual "Dirty Dozen" food list, released a study to the national press that has many civilians worried about Hexavalent Chromium in drinking water across the country. The study found trace levels of Chromium-6 in 31 out of the 35 cities it sampled. The group also produced a map, since reproduced in several news outlets, that showed Chromium-6 levels measured across the country as measured in parts per billion. Among the high points was Norman, Okla., which showed a level of "12.90" ppb.
Another distributed stat is the average level found, 0.18 ppb.
The problem with this: the national standard is almost eight times the highest reported level in the study. The baseline of safety the environmental group used is 0.06 ppb, a target set by California. However, the current national limit isn't anywhere near that. It's 100 ppb, or 0.1 mg/L. This is currently under IRIS review, but even if a new limit is set (likely), it is unlikely to be as stringent as that proposed by California.
In light of the study, California Sen. Barbara Boxer, D, and Dianne Feinstein, D, announced they will push the EPA to meet those same limits.
The EPA on Wednesday responded by issuing a statement reminding the nation of its current standards, and its regular, ongoing IRIS review of the chemical. Key points:
The IRIS review of Hexavalent Chromium is in the middle of the external peer review stage, with a final assessment likely released by September 2011. Until then, it will be hard to guess what the new standard would look like. As low as the California recommendation is unlikely. Most recently, the agency on Nov. 11, 2010, decided it would extend the public comment period for that review through Dec. 29, 2010.
SOURCES: EPA press release, EWG press release, Washington Post article.
On Monday, Dec. 20, 2010, the Environmental Working Group (EWG), an environmentalist organization most famous for its annual "Dirty Dozen" food list, released a study to the national press that has many civilians worried about Hexavalent Chromium in drinking water across the country. The study found trace levels of Chromium-6 in 31 out of the 35 cities it sampled. The group also produced a map, since reproduced in several news outlets, that showed Chromium-6 levels measured across the country as measured in parts per billion. Among the high points was Norman, Okla., which showed a level of "12.90" ppb.
Another distributed stat is the average level found, 0.18 ppb.
The problem with this: the national standard is almost eight times the highest reported level in the study. The baseline of safety the environmental group used is 0.06 ppb, a target set by California. However, the current national limit isn't anywhere near that. It's 100 ppb, or 0.1 mg/L. This is currently under IRIS review, but even if a new limit is set (likely), it is unlikely to be as stringent as that proposed by California.
In light of the study, California Sen. Barbara Boxer, D, and Dianne Feinstein, D, announced they will push the EPA to meet those same limits.
The EPA on Wednesday responded by issuing a statement reminding the nation of its current standards, and its regular, ongoing IRIS review of the chemical. Key points:
- Currently, the total chromium standard is 0.1 mg/L (100 parts per billion).
- Our latest data shows no U.S. utilities are in violation of the standard.
The IRIS review of Hexavalent Chromium is in the middle of the external peer review stage, with a final assessment likely released by September 2011. Until then, it will be hard to guess what the new standard would look like. As low as the California recommendation is unlikely. Most recently, the agency on Nov. 11, 2010, decided it would extend the public comment period for that review through Dec. 29, 2010.
SOURCES: EPA press release, EWG press release, Washington Post article.
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