By Lynn L. Bergeson and Carla N. Hutton
The U.S. Environmental Protection Agency (EPA) announced on November 20, 2020, the availability of a supplemental analysis to the draft risk evaluation of 1,4-dioxane under the Toxic Substances Control Act (TSCA). 85 Fed. Reg. 74341. EPA states that it developed the supplemental analysis in response to public and peer review comments on the draft risk evaluation. The supplemental analysis includes eight consumer uses, including surface cleaners, laundry/dishwashing detergents, and paint/floor lacquer, where 1,4-dioxane is present as a byproduct. The supplemental analysis also assesses exposure to the general population from 1,4-dioxane in surface water. In the supplemental analysis, EPA preliminarily found no unreasonable risk to consumers from the eight conditions of use assessed. EPA also preliminarily found no unreasonable risks under any of the conditions of use to the general population from exposure to 1,4-dioxane. Comments are due December 10, 2020. More information on the draft risk evaluation of 1,4-dioxane is available in our July 2, 2019, memorandum.