On August 31, 2021, the U.S. Environmental Protection Agency (EPA) released the final scope documents for the Toxic Substances Control Act (TSCA) risk evaluations of diisodecyl phthalate (DIDP) and diisononyl phthalate (DINP). 86 Fed. Reg. 48695; 86 Fed. Reg. 48693. In its August 31, 2021, press release, EPA notes that both DIDP and DINP “belong to a family of chemicals called phthalates and are commonly used as plasticizers in the production of plastic and plastic coating to increase flexibility.”

According to EPA, the final scope documents reflect the policy changes on risk evaluations announced in June 2021. This includes plans to consider exposure pathways that may be regulated outside of TSCA, like air and water, and potential for exposures to fenceline communities (i.e., communities near industrial facilities). EPA states that “[a]ssumptions that personal protective equipment (PPE) in occupational settings will always be properly utilized will not be used as the basis for the risk determination. Use of PPE, and other ways industry protects its workers, will be assessed during the risk evaluation and considered as potential ways to address unreasonable risks during the risk management process.” More information on the policy changes is available in our July 1, 2021, memorandum.

The final scope documents explain EPA’s plan for the risk evaluations, including the conditions of use, hazards, exposures, and the potentially exposed or susceptible subpopulations that EPA will consider. The documents also include a description of the reasonably available information and the best available science approaches that EPA will use; a conceptual model that outlines the potential hazards and exposures throughout the life cycle of the chemical; an analysis plan to identify the approaches and methods EPA will use to assess health and environmental risks; and a plan for peer review.