The Nickel Report

On December 22, 2022, EPA’s Integrated Risk Information System (IRIS) Program released its ORD Staff Handbook for Developing IRIS Assessments (IRIS Handbook). EPA began working on the approaches in the IRIS Handbook after a 2011 National Research Council report recommended several improvements to the overall IRIS assessment process. In 2020, EPA released a draft IRIS Handbook for public comment and commissioned a peer review by the National Research Council.

Established in 1985 to ensure Agency-wide consistent toxicity evaluations, IRIS assessments provide chemical toxicity values for noncancer and cancer human health effects resulting from chronic exposure to chemicals. These values are often utilized in EPA regulations under the Clean Air Act (CAA), the Safe Drinking Water Act (SDWA), and the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA). While chemical risk evaluations conducted under the Toxic Substances Control Act (TSCA) require more information and analysis than that provided by an IRIS assessment, IRIS assessments will likely continue to be used to inform TSCA risk evaluations. State agencies and international bodies also rely on IRIS assessments.

8.18.2021 EPA Finalizes Hazard Assessments for Two Fuel Additives (ETBE and tert-Butanol):

On August 18^th, EPA finalized the long-awaited hazard assessments for both Ethyl Tertiary Butyl Ether (ETBE) and tert-Butyl Alcohol (tert-Butanol).  ETBE was previously added to gasoline to increase its octane levels. It is still registered with EPA for use as a fuel additive, but it is not used currently in the United States.  tert-Butanol is one of the primary metabolites of ETBE and has also been used as a fuel oxygenate. It is also used for other purposes including as a solvent and as a dehydrating agent.

On November 9, 2020, EPA’s Office of Research and Development (ORD) released its long-awaited draft handbook that details the office’s process for developing chemical hazard assessments for its Integrated Risk Information System (IRIS) Program. The ORD Staff Handbook for Developing IRIS Assessments (IRIS Handbook) gives useful insight into ORD’s process to develop its IRIS assessments, which provide important toxicological information that federal and state environmental agencies consider when making regulatory and cleanup decisions under multiple statutory programs. EPA will accept comments on the draft handbook and charge questions until March 1, 2021.