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IRIS Program Releases Second Set of Preliminary Materials for Hexavalent Chromium

EPA has released the second of two sets of preliminary materials for the IRIS assessment of hexavalent chromium for public comment and discussion. The second set of preliminary materials includes an updated literature search and associated strategy, an approach for evaluating and selecting critical epidemiological (human) literature, evidence tables for critical epidemiological studies, and a preliminary summary of mechanistic and toxicokinetic studies pertinent to the assessment of hexavalent chromium. The IRIS assessment is looking at seven key science questions:

  •  Methodological considerations for evaluating epidemiology studies
  • Inhalation cancer dose-response modeling
  • Toxicokinetic considerations for dose-response
  • Mechanistic studies database
  • Chromium-DNA adducts
  • In vitro mutagenicity/genotoxicity studies of hexavalent chromium
  • Definitions of mutagenicity and genotoxicity

The results of the IRIS assessment will provide basic information on health impacts that can support any future development of an MCL and MCLG for hexavalent chromium.  The assessment for hexavalent chromium along with Diisononyl Phthalate (DINP) will be discussed during the October IRIS Bimonthly Public Science Meeting. This public meeting will be held October 29-30, 2014 at the U.S. EPA Conference Center, One Potomac Yard (South Building), 2777 South Crystal Drive, Arlington, Virginia 22202.   Registration for the meeting is now open.

Please visit the October IRIS Bimonthly Public Science Meeting website for additional information on the meeting and to access materials on the assessment.