EPA Risk Evaluation For 1,4-Dioxane

On November 14, 2024, the U.S. Environmental Protection Agency ("EPA") determined that 1,4-dioxane presents an unreasonable risk of injury to human health under its conditions of use. This determination now requires that EPA to propose risk management regulations under section 6(a) of the Toxic Substances Control Act ("TSCA") to eliminate the unreasonable risk.

This risk determination applies to many entities, including those that manufacture, import, process, distribute, use, and dispose of 1,4-dioxane particularly for use as a solvent or chemical stabilizer. This unreasonable risk determination is expected to lead to restrictions, which could include regulation of the manufacturing, processing, distribution, or disposal of 1,4-dioxane, and could lead to additional notification or recordkeeping requirements. The unreasonable risk determination may also affect the implementation of remedy selection decisions at sites contaminated with 1,4-dioxane.