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Chemical Regulation

EPA seeks to ban trichloroethylene

US agency proposes to end most uses of the carcinogenic solvent within 1 year

by Britt E. Erickson
October 25, 2023

A lithium ion battery pack and power connections for an electric vehicle.
Credit: Shutterstock
Use of trichloroethylene to produce lithium ion battery separators for electric vehicles would be allowed for 10 years under a proposed rule.

After years of evaluating the risks of the solvent trichloroethylene (TCE), the US Environmental Protection Agency has concluded that there are no safe uses of the carcinogenic chemical.

Under a proposed rule released Oct. 23, the agency plans to ban TCE in most industrial and consumer products within 1 year. A few limited uses of TCE, including the production of separators used in electric vehicle batteries and the manufacture of rocket booster nozzles, would be exempt from the ban for 10 years.

TCE was once widely found in metal degreasers and in cleaning and automotive care products. Safer alternatives to TCE are now available for these products, according to the EPA. Although most consumer uses of TCE have been eliminated, a few products containing the toxic chemical can still be purchased from online retailers, the agency says.

TCE is also used as an intermediate in the production of certain hydrofluorocarbons (HFCs) that are used as refrigerants. These refrigerants are being phased out because HFCs are potent greenhouse gases.

Exposure to very low levels of TCE is associated with cancer and adverse neurological, developmental, and immunological effects, and the risks are irreversible, the EPA says in an evaluation published in January 2023. The assessment builds on earlier assessments published by the EPA in 2020 and 2014.

TCE is a contaminant in soil and groundwater at many hazardous waste sites and surrounding areas, stemming from decades of widespread use and improper disposal. “For far too long, TCE has left a toxic legacy in communities across America,” Michal Freedhoff, assistant administrator for the EPA’s Office of Chemical Safety and Pollution Prevention, says in a statement.

The American Chemistry Council, which represents chemical manufacturers, says the proposal is overly restrictive. The industry group says the EPA is overestimating exposure to TCE. “Where uses of chemistries have decreased over time, this must be reflected in EPA’s underlying risk assessment, because decreased use reduces potential exposure,” the ACC says in a statement. “Here, for example, in the underlying risk assessment, EPA’s exposure assessments were not realistic or reflective of current industrial hygiene practices.”

Environmental groups welcome the EPA’s proposal—the fifth rule aimed at controlling a high-priority chemical since the Toxic Substances Control Act was amended in 2016. The four other rules target asbestos, carbon tetrachloride, methylene chloride, and perchloroethylene. The EPA plans to propose restrictions on five additional high-priority chemicals in the coming months.

“The Biden EPA is once again putting the health of workers and consumers first,” Scott Faber, senior vice president of government affairs at the Environmental Working Group, says in a press release. “EWG applauds this move to ban most uses of TCE.”

The EPA will accept comments on the proposed rule for 45 days after it is published in the Federal Register.


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