The US Environmental Protection Agency has released draft exposure assessments for two chemicals, trans-1,2-dichloroethylene and 1,2-dichloropropane, under the Toxic Substances Control Act.
The agency published technical support documents explaining how it estimates human and environmental exposure to these widely used industrial solvents.
EPA’s draft assessment for trans-1,2-dichloroethylene characterises releases to air, water, and land across occupational, consumer, general population, and environmental pathways.
The assessment covers the chemical’s manufacture, processing, laboratory use, disposal, and all reasonably foreseen industrial, commercial, and consumer applications.
Air is identified as the primary exposure pathway for trans-1,2-dichloroethylene, given the chemical’s physical properties and documented release patterns.
The draft assessment for 1,2-dichloropropane similarly evaluates releases to air, water, and land, covering an equivalent range of exposure scenarios and use categories.
EPA’s draft hazard assessment for 1,2-dichloropropane identified potential cancer and non-cancer health concerns, including effects on the nervous system.
The exposure technical support documents are intended to give stakeholders insight into the scientific methods and data underpinning EPA’s broader draft risk evaluations.
EPA released the documents early to allow the public additional time to review the scientific analyses ahead of a scheduled August review by the Science Advisory Committee on Chemicals.
The Science Advisory Committee on Chemicals is conducting independent peer review of human health and environmental assessments for both chemicals during a meeting running from 3 to 7 August 2026.
The full public comment period will open alongside the draft risk evaluations when they are formally released, with EPA committing to consider all input before finalising its assessments.
Public comments on the exposure technical support documents will be accepted through their respective TSCA dockets, referenced as EPA-HQ-OPPT-2018-0465 and EPA-HQ-OPPT-2018-0428.
All existing protections for both chemicals remain in place while the agency completes its review, and the draft documents do not represent EPA’s final determination on the risks they pose.