On July 24, 2026, the U.S. Environmental Protection Agency (EPA) published a notice in the Federal Register, formally releasing the draft risk assessment for 1,1,2-trichloroethane and opening the document for public comment. Based on existing scientific evidence, the EPA has preliminarily determined that this chemical substance poses an unreasonable risk to human health under certain conditions of use (COUs).
Assessment Background and Scope
1,1,2-Trichloroethane is an industrial chemical used primarily in plastics and petrochemical manufacturing, as well as in industrial adhesives, sealants, and laboratory chemicals. The substance was designated as a high-priority substance under the Toxic Substances Control Act (TSCA) in December 2019, with the scope of the risk assessment defined in 2020. This draft assessment covers the full lifecycle of the chemical, including manufacture, processing, use, and disposal.
Key Risk Findings
The EPA evaluated exposure risks for multiple populations in the draft assessment:
- Workers and Occupational Non-Users (ONUs): Exposed via inhalation and dermal contact, facing acute, intermediate, and chronic non-cancer and cancer risks
- Consumers: Exposed via dermal contact and inhalation when using adhesive products containing the substance, facing acute and chronic non-cancer risks
- General Population and Sensitive Subgroups: Including fenceline communities and Potentially Exposed or Susceptible Subpopulations (PESS), facing acute and chronic non-cancer and cancer risks
- Ecological Environment: Poses acute and chronic risks to aquatic and terrestrial species
Public Comment Period
The EPA is now accepting public comments on the draft risk assessment, with a comment deadline of September 28, 2026. Comments may be submitted through the Federal Regulations website (regulations.gov) under Docket ID EPA–HQ–OPPT–2018–0421.
Next Steps
After collecting and reviewing public comments and peer review input from the Science Advisory Committee on Chemicals (SACC), the EPA will issue a final risk assessment. Under Section 6 of the Toxic Substances Control Act (TSCA), the EPA must, based on the final assessment results, determine whether this chemical substance poses an unreasonable risk to human health or the environment under its conditions of use, in accordance with the weight of the scientific evidence.
