Independent Peer Review of the Hexavalent Chromium Cancer Assessment for the Texas Commission on Environmental Quality, State of Texas



What: Peer Review of Section 4.2, Carcinogenic Potential, of the Development Support Document for Hexavalent Chromium, Draft March 2013


NOTE: TERA and TCEQ evaluated the peer reviewers’ written comments and determined that there were not enough significant scientific issues or disagreements that indicated a need to have the experts meet in a teleconference.  Therefore, the written comments of the reviewers (and public comments) will form the peer review report.  The peer review report will be available on the review web page by the end of June 2013.


Toxicology Excellence for Risk Assessment (TERA) is organizing an expert external peer review of the Texas Commission on Environmental Quality's (TCEQ's) Development Support Document for Hexavalent Chromium, Draft March 2013.  This peer review will be conducted as a letter review with a follow-up conference call. The conference call date is still to be determined.


The Toxicology Division of the Texas Commission on Environmental Quality (TCEQ) has prepared a draft Development Support Document (DSD) that outlines the hazard assessment and dose-response processes used to derive health-protective Effects Screening Levels (ESLs) and Unit Risk Factors (URFs) for hexavalent chromium (CrVI). The draft DSD includes Section 4.2, which documents the derivation of an inhalation unit risk factor (URF) and air concentrations corresponding to the policy-based 1 in 100,000 excess risk level based on lung cancer mortality. These toxicity values are used in the evaluation of air permit applications and ambient air data and were developed using RG-442 TCEQ Guidelines to Develop Toxicity Factors (TCEQ 2012).


Public Comments:  Technical and Scientific Comments from the public will be accepted via email and will be included as an appendix to the final peer review report.  All submitted comments must have your name, organization, mailing address, and email address and should address technical or scientific issues presented in the document.  All comments should be submitted as a Word file and can be directly emailed to Ms. Melissa Vincent at  Comments were due by May 24, 2012 and are no longer being accepted.


Report of Letter Peer Review of the TCEQ's Hexavalent Chromium - Section 4.2 Carcinogenic Potential - Development Support Document (pdf)


Charge to Peer Reviewers (pdf)


Biographical Sketches of Reviewers (pdf)



For more information, contact Jacqueline Patterson at or 513-542-7475 x29