On March 5, 2025, the U.S. Environmental Protection Agency (EPA) extended the comment period on the draft scope of the risk evaluation to be conducted under the Toxic Substances Control Act (TSCA) for vinyl chloride. 90 Fed. Reg. 11315. As reported in our January 28, 2025, memorandum, under TSCA, the scope documents must include the conditions of use (COU), hazards, exposures, and the potentially exposed or susceptible subpopulations (PESS) that EPA expects to consider in conducting its risk evaluation. The purpose of risk evaluations is to determine whether a chemical substance presents an unreasonable risk of injury to health or the environment under the COUs, including unreasonable risk to PESS identified as relevant to the risk evaluation by EPA, and without consideration of costs or non-risk factors. Comments on the draft scope of the risk evaluation for vinyl chloride are due April 2, 2025.