US: EPA TSCA Evaluation Finds 1,2-Dichloropropane Unreasonable Risk

On September 4, 2026, the US Environmental Protection Agency (EPA) published its draft risk evaluation for 1,2-dichloropropane under Toxic Substances Control Act (TSCA) Section 6, opening a 60-day public comment period that closes November 3, 2026 (91 FR 56882). EPA preliminarily determines that 1,2-dichloropropane poses unreasonable risk to human health, driven by 11 occupational conditions of use and three consumer uses in cleaning and furnishing care products. Manufacturers, importers, processors, and commercial users of the substance now have a narrow window to shape the findings that will drive a binding Section 6(a) risk-management rule.

1,2-Dichloropropane is a volatile chlorinated solvent manufactured mainly as a byproduct, with a national aggregate production volume of 100 to 250 million pounds per year reported under the 2024 Chemical Data Reporting. Industrial and commercial uses include processing as a reactant, laboratory chemical use, and residual presence in some imported cleaning, polish, and wax products.

Who must act on the draft risk evaluation, and by when?

Comments must be received on or before November 3, 2026, submitted to docket EPA-HQ-OPPT-2018-0428 (Regulations.gov docket). The notice is directed broadly, but the exposed actors are concrete: manufacturers, including importers under the TSCA section 3 definition, of 1,2-dichloropropane; processors using it as a reactant; commercial laboratories using it as a laboratory chemical; and importers of residual cleaner, polish, or wax products that still contain it. Trade associations, NGOs, and state, local, and Tribal governments are also invited. EHS and TSCA compliance leads at these entities should treat the deadline as hard: comments received after November 3, 2026 will not be considered in the final evaluation.

What unreasonable risk does EPA preliminarily find?

EPA's draft concludes that 1,2-dichloropropane poses unreasonable risk to human health under 11 occupational conditions of use, covering both workers and occupational non-users (ONUs), and under three consumer uses tied to all-purpose liquid cleaners, polishes, and waxes. The agency assessed acute, intermediate, and chronic non-cancer and cancer risks to workers and ONUs, acute and chronic non-cancer risks to consumers, and acute and chronic non-cancer and cancer risks to the general population, including fenceline communities and potentially exposed susceptible subpopulations. Environmental risks to aquatic and terrestrial species were also evaluated.

The occupational exposure routes are inhalation and dermal for workers, and inhalation for ONUs. The consumer routes are dermal and inhalation during the intended use of affected products. EPA specifically flags stone polishing and cleaning as a use it wants to characterize, including whether that use is reasonably foreseen and whether it is being reestablished in the United States through imported products.

Which data gaps is EPA asking commenters to fill?

EPA requests targeted information that directly affects whether each condition of use stays in the unreasonable-risk column. The agency specifically seeks:

• Whether 1,2-dichloropropane is manufactured as a primary product, or by manufacturing processes not discussed in the draft;
• How the substance is distributed for use as a laboratory chemical and in cleaning and furnishing care products;
• For commercial laboratories (occupational exposure scenario #5), the amounts used daily (kg/site-day) and yearly (kg/site-yr), plus the personal protective equipment and engineering controls in place;
• Information on use in all-purpose liquid cleaners, polishes, and waxes, particularly for stone polishing and cleaning, including whether this is a reasonably foreseen use and whether it is being reestablished in the United States.

Commenters should cite public data where possible and describe non-public supporting data to the extent permissible, because the agency weighs the scientific record on a weight-of-the-evidence basis.

What comes after a final unreasonable-risk finding?

A final unreasonable-risk determination triggers EPA's obligation to issue a TSCA Section 6(a) risk-management rule, which can restrict or prohibit the conditions of use found to present unreasonable risk. The 1,2-dichloropropane file therefore moves from consultation toward potential use restrictions, with exposure-reduction obligations likely for manufacturers, processors, and commercial labs. Two parallel TSCA developments shape how narrow or broad that rule may be: EPA's proposed framework rule (RIN 2070-AL27) would let the agency narrow risk evaluations by excluding particular conditions of use and assuming personal protective equipment, a departure from the prior whole-chemical approach, and the existing risk-management rules for methylene chloride and chrysotile asbestos remain under Fifth Circuit review. Compliance leads should track both tracks.

Obsidian's continuous, per-jurisdiction real-time monitoring surfaces this kind of change the moment it publishes, so compliance teams see the consultation opening on day one rather than after the comment window has narrowed.

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Next steps: confirm whether your operation manufactures, imports, processes, or uses 1,2-dichloropropane as a reactant, laboratory chemical, or in cleaner, polish, or wax products; calendar the November 3, 2026 comment deadline and assign a technical author; gather usage amounts, PPE, and engineering-control data for any commercial laboratory operations; and brief EHS and procurement teams on the Section 6(a) rule now moving toward restrictions.