Decision Nears on Lowering Allowable Arsenic Levels
Prior to its September meeting, the Environmental Protection Agency’s (EPA’s) Science Advisory Board (SAB) is expected to accept or reject a report, approved by an SAB Work Group, describing inorganic arsenic as an oral carcinogen.  The report, “Toxicological Review of Inorganic Arsenic,” proposes a twenty fold increase (from 1.5 to 25.7 mg As/kg-day-1) in the oral cancer slope factor for inorganic arsenic published in EPA’s Integrated Risk Information System (IRIS).  The cancer slope factor increase would significantly lower allowable levels of inorganic arsenic for most media.  If the SAB accepts the report and the Office of Management and Budget approves it, the new cancer slope factor would immediately increase the likelihood of crossing health thresholds in site-specific or industrywide quantitative multimedia cancer risk assessments.  Ultimately, the change would impact EPA’s regulatory programs, including those for drinking water, ambient water quality criteria, and soil cleanup.  EPRI submitted comments on the draft report to the official docket (Docket ID No. EPA-HQ-ORD-2010-0123) and directly to the SAB Work Group, which met April 6–7 to review the draft report in a public forum (public comments are available here).  For more information, contact Sharan Campleman, (650) 855-2331, scampleman@epri.com, or John W. Goodrich-Mahoney, (202) 293-7516, jmahoney@epri.com.