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Assessing and Managing Chemicals under TSCA

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 final risk evaluation in September 2020. The next step in the process required by TSCA is addressing these risks. EPA will now begin the process of developing ways to address the unreasonable risks identified and has up to one year to propose and take public comments on any risk management actions.

Find information about other chemicals undergoing risk evaluations under TSCA

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Background on HBCD

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.

Uses of HBCD

HBCD is primarily used as a flame retardant in building materials like insulation, solder paste, recycled plastics, and automobile replacement parts.

Risk Evaluation of HBCD under Amended TSCA

In September 2020, EPA released the final risk evaluation for HBCD. The final risk evaluation for HBCD shows that there are unreasonable risks to the environment for six out of 12 conditions of use. Additionally, EPA found unreasonable risks to workers and occupational non-users from the use and disposal of HBCD in building and construction materials. EPA did not find unreasonable risks to the general population or consumers.

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.

Review of HBCD Prior to Amended TSCA

Prior to the Frank R. Lautenberg Chemical Safety for the 21st Century Act, EPA began the review of HBCD and published the following information.