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More Insight On EPA’s Regulation Of Hexavalent Chromium And Perchlorate

Grayson_Lynn_COLORBy E. Lynn Grayson


In testimony before the Senate Environment and Public Works Committee, EPA Administrator Lisa Jackson confirmed that EPA likely will regulate hexavalent chromium in tap water but only after completing its health assessment study of the toxic contaminant. Jackson told the committee that the regulatory process would take up to two years including the completion of the human health assessment study and the ensuing public comment period. The final study is now being peer-reviewed and should be completed later this year.

For now, EPA's maximum contaminant level for total chromium is 100 ppb. California has proposed a health protection goal of 0.02 ppb for hexavalent chromium.

In a related action, EPA also announced on February 2nd that the Agency will develop the first national standard for perchlorate in drinking water as well as a new drinking water strategy addressing up to 16 chemicals, both regulated and unregulated substances.


The decision to adopt the first-ever national standard reverses prior Agency action but comes after EPA directed further evaluation of the emerging science of perchlorate. Perchlorate is both naturally occurring and a man-made chemical and scientific research indicates that it may impact the normal function of the thyroid. EPA will move forward with a formal rulemaking process including input from key stakeholders and a public comment period.

More information on perchlorate:

Drinking Water Strategy

In addition, EPA will be developing one regulation addressing chemicals that may cause cancer. The list includes industrial solvents such as TCE and PCE as well as other regulated and unregulated contaminants discharged from industrial operations. The VOC standard will be developed as part of EPA's new strategy for protecting drinking water. A key principle of the strategy is to address contaminants as groups rather than individually to provide public health protections more quickly.

More information on drinking water strategy: