ASDWA Provides Support for EPA’s Proposed Procedures to Evaluate Risks from Chemicals under TSCA

ASDWA submitted comments to EPA on December 14, generally supporting EPA’s proposed rule, Procedures for Chemical Risk Evaluation Under the Toxic Substances Control Act (TSCA). The proposal amends the procedural framework rule for conducting risk evaluations under TSCA. Most notably, the proposed rule ensures that risk evaluations include all exposure routes and pathways relevant to the chemical substance under the conditions of use, including those regulated under other Federal statutes. When EPA proposed the Supplemental Analysis to the Draft TSCA Risk Evaluation for 1,4-dioxane in 2020, the Agency chose to exclude key exposure routes, such as drinking water, with the assumption that the Safe Drinking Water Act (SDWA) is the appropriate path to manage those exposures. ASDWA submitted comments in response to the analysis disagreeing with this approach, highlighting that since there is no current drinking water standard for 1,4-dioxane, SDWA is not managing this exposure pathway. Additionally, the Agency has no clear timeframe for potentially regulating 1,4-dioxane under the SDWA, if ever. EPA has since revised its risk determination for 1,4-dioxane, this time including drinking water exposures under the assessment. ASDWA joined the American Water Works Association and the Association of Metropolitan Water Agencies in support of the action.

ASDWA’s December 14 comments agree with the EPA’s assessment under this new proposal that, for future TSCA risk evaluations, it is unclear how EPA would have sufficient information to determine if a chemical substance poses a risk to health or the environment that should be addressed under TSCA without considering all relevant aspects of the risk.