Risk Evaluation for Cyclic Aliphatic Bromide Cluster (HBCD)
EPA evaluated the cyclic aliphatic bromide cluster (HBCD) under the amended Toxic Substances Control Act (TSCA) and completed the risk evaluation in September 2020. In June 2022, EPA released a final revised risk determination for HBCD. The revisions to the risk determination were made in accordance with the path forward for the first 10 risk evaluations under TSCA laid out by EPA in June 2021. The final revised risk determination is based on HBCD as a whole chemical substance and does not assume that all workers exposed to HBCD are protected by personal protective equipment.
EPA will next propose a regulation to address the unreasonable risk HBCD presents to human health and the environment. EPA will develop ways to address the unreasonable risk identified and will propose and take public comments on any risk management action.
On this page:
- Background on HBCD
- Uses of HBCD
- Risk Evaluation of HBCD under Amended TSCA
- Review of HBCD prior to Amended TSCA
HBCD is a flame retardant. Use of HBCD has declined dramatically over the past few years, primarily due to the use of replacement chemicals. U.S. manufacturers have indicated complete replacement of HBCD in their production lines, including the depletion of stockpiles and cessation of export.
HBCD is primarily used as a flame retardant in building materials like insulation, solder paste, recycled plastics, and automobile replacement parts.
In June 2022, EPA released a final revised risk determination for HBCD. The final revised risk determination finds that HBCD presents an unreasonable risk of injury to human health and the environment when evaluated under its conditions of use.
In the September 2020 risk evaluation, EPA reviewed the exposures and hazards of HBCD uses. In September 2020, EPA released the final risk evaluation for HBCD.
In the final revised risk determination, the agency assessed the impact of HBCD on aquatic and sediment-dwelling species through surface water and sediment exposures, and to terrestrial species. After reviewing these data, EPA found that risk from import, processing, recycling, commercial use, and disposal of HBCD drive the whole chemical determination of unreasonable risk to the environment.
EPA also determined unreasonable risk to workers from the use of HBCD from both short- and long-term inhalation exposure when personal protective equipment (such as respirators) is not assumed to be used. Risk from import, processing, commercial use, and disposal of HBCD drive the whole chemical determination of unreasonable risk to human health.
In June 2019, EPA released the draft risk evaluation for HBCD for public comment and peer review.
In June 2017, EPA released the scope document for HBCD which included the hazards, exposures, conditions of use, and the potentially exposed or susceptible subpopulations EPA expected to consider in its risk evaluation. In June 2018, EPA released the problem formulation for HBCD which refined the scope of the risk evaluation by clarifying the chemical conditions of use that EPA expected to evaluate and describing how EPA expected to conduct the evaluation.
After releasing the scope documents, the dockets for each of the first 10 chemicals were open for public comments. Read EPA’s Responses to Public Comments Received on the Scope Documents for the First Ten Chemicals for Risk Evaluation under TSCA. This document addresses cross-cutting public comments received in response to EPA publishing the scope documents.
Prior to the Frank R. Lautenberg Chemical Safety for the 21st Century Act, EPA began the review of HBCD and published the following information.