EPA Releases New Human Health Assessment for Hexavalent Chromium

EPA recently released its Draft IRIS Human Health Assessment of Hexavalent Chromium, which will be used to set regulatory standards for hexavalent chromium. The Draft IRIS Assessment is overly conservative and does not use the best available peer-reviewed science. Based on the draft assessment EPA’s new safe concentration of hexavalent chromium would equate to 35 parts per trillion (ppt). This is nearly 3,000 times lower than EPA’s current drinking water standard.

EPA currently has in place a maximum contaminant level (MCL) of 100 parts per billion (ppb) total chromium based on the assumption of 100 percent hexavalent chromium in the water. Results from a series of state of the art, peer-reviewed studies provide support that the current EPA drinking water standard is human health protective.

This research has been validated by other regulatory bodies, including Health Canada, the World Health Organization, and the Food Safety Commission of Japan. For example, in 2020 the World Health Organization issued a final background document that recommends retaining the current WHO guideline value for total chromium (50 ppb) based on newer, high-quality data from chronic drinking water carcinogenicity studies noting that the overall weight-of-evidence supports this level as safe. Similarly, in 2018 Health Canada issued a final maximum acceptable concentration of 50 ppb for total chromium, finding the weight of evidence, including review of the large body of peer-reviewed published studies.

The draft IRIS assessment is at odds with the findings of over 30 peer-reviewed studies supporting the current health standards for hexavalent chromium. NASF will be engaging EPA to understand why its assessment is not consistent with the best available science.

If you have any questions or would like more information regarding this process, please contact Christian Richter or Jeff Hannapel with NASF at crichter@thepolicygroup.com or jhannapel@thepolicygroup.com.

This update is courtesy of the National Association for Surface Finishing (NASF). For more information or to become a member, visit nasf.org.