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Petitions to Add 1-BP (nPB) to the Clean Air Act List of Hazardous Air Pollutants

Note: 1-bromopropane (1-BP) is also known as nPB

Petition Summary

Under the Clean Air Act (CAA), EPA is required to evaluate and control emissions of hazardous air pollutants (also known as air toxics). The CAA allows any person to petition EPA to modify the list by adding or deleting a substance. To add a substance, the petition 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.

EPA received petitions requesting 1-BP be added to the CAA list of hazardous air pollutants. The chemical  1-bromopropane (1-BP), also known as n-propyl bromide (nPB), is a solvent used in electronics and metal cleaning, surface coatings, dry cleaning, adhesives, and as an intermediate chemical in the manufacture of pharmaceuticals and agricultural products.

In 2015, EPA determined that the petitions were complete. To aid the Agency in its technical review of the petitions, EPA published a Federal Register notice requesting public comment on the complete petitions. EPA conducted a thorough review of the petitions, relevant scientific studies, and the public comments received. Based on the evidence of the carcinogenicity and toxicity of 1-BP, EPA concluded that 1-BP is reasonably anticipated to cause adverse effects to human health. In 2017, EPA issued a draft notice of its rationale for granting petitions to add 1-BP to the list of hazardous air pollutants contained in the CAA.

On June 12, 2020, Administrator Wheeler signed the final notice granting petitions from the Halogenated Solvents Industry Alliance (HSIA) and the New York State Department of Environmental Conservation (NYSDEC) to add 1-BP to the Clean Air Act (CAA) list of air toxics, and on June 18, 2020, the final notice was posted to the Federal Register. Following this action, the EPA will take a separate regulatory action to add 1-BP to the list of HAP under CAA section 112(b)(1). After 1-BP is added to the list, EPA may revise air toxic standards for source categories that emit 1-BP or add new source categories for sources of 1-BP emissions. This final notice does not have any direct impacts. No regulatory requirements will come into effect until EPA adds 1-BP to the CAA list of air toxics.

Petition Review History

6/18/2020 - Federal Register Notice: Granting Petitions To Add 1-bromopropane to the List of Hazardous Air Pollutants

6/6/2017 - Notice: Extension of Comment Period 

3/6/2017 - Notice: Extension of Comment Period

1/9/2017 - Notice: Draft Rationale for Granting Petitions to Add 1-bromopropane to the List of Hazardous Air Pollutants

2/6/2015 - Notice of Complete Petition: Petition to Add 1-bromopropane to the List of Hazardous Air Pollutants

Additional Resources

Docket - Petition to Add 1-bromopropane to the List of Hazardous Air Pollutants

1-bromopropane Draft Toxic Substances Control Act Risk Evaluation and TSCA Science Advisory Committee on Chemicals Review of Risk Evaluation for 1-bromopropane Docket

Clean Air Act List of Hazardous Air Pollutants

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