EPA Adds 1-Bromopropane to List of Hazardous Air Pollutants

A final rule issued by EPA adds the chemical 1-bromopropane (1-BP), or n-propyl bromide, to the Clean Air Act list of hazardous air pollutants. EPA’s final rule, which was published in the Federal Register on Jan. 5, is the final step in the process of modifying the list. The agency’s action marks the first time a substance has been added to the list since it was created in 1990. (EPA previously amended the list four times to remove or delist a hazardous air pollutant.) According to EPA, hazardous air pollutants are those that are “known or suspected to cause cancer or other serious health effects, such as reproductive effects or birth defects, or adverse environmental effects.” 1-BP, a solvent used in electronics and metal cleaning, surface coatings, and dry cleaning, is also used as an intermediate chemical in the manufacture of pharmaceuticals and agricultural products. A risk evaluation published by EPA in August 2020 identifies “unreasonable” risks to workers associated with 1-BP under certain conditions of use.

Under the Clean Air Act, any person can petition EPA to modify the list of hazardous air pollutants by adding or deleting a substance. The agency states that petitions must provide adequate data for EPA to determine that “emissions, ambient concentrations, bioaccumulation, or deposition of the substance are known to cause, or may reasonably be anticipated to cause, adverse effects to human health or the environment” (PDF). In June 2020, EPA granted the petitions of two organizations—the Halogenated Solvents Industry Alliance and the New York State Department of Environmental Conservation—to add 1-BP to the list.

The effective date for the listing of 1-BP as a hazardous air pollutant is Feb. 4, 2022. According to a Q&A document (PDF) published last week, EPA plans to develop a rule to address the “impacts, implications, and requirements” associated with the addition of a new chemical to the hazardous air pollutant list. The agency anticipates that the proposed regulatory infrastructure will be published this year and finalized in early 2023.