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Assessing and Managing Chemicals under TSCA

Risk Evaluation for Cyclic Aliphatic Bromide Cluster (HBCD Cluster)

The cyclic aliphatic bromide cluster (HBCD) is currently undergoing risk evaluation under the Toxic Substances Control Act (TSCA). EPA is evaluating HBCD because the 2016 amendments to TSCA directed EPA to pick its first ten chemicals for evaluation from the TSCA Work Plan, and HBCD is on the Work Plan. In June 2019, EPA released the draft risk evaluation for HBCD.

In the draft risk evaluation for HBCD, EPA did not find unreasonable risk to the general population, consumers, workers, or the environment. These initial determinations may change as our assessment becomes more refined through the public and peer review process.

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Chemical Description of HBCD

HBCD is a flame retardant that has been used primarily in construction materials, which may include structural insulated panels. While HBCD is known to build up in the environment over time and presents potential human health concerns based on animal test results, it is unlikely that most people would be exposed to this chemical which means that potential risks from this chemical are low. 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 Included in the Problem Formulation, Risk Evaluation, and Scope

In the draft risk evaluation, EPA looked at 8 conditions of use associated with the manufacturing (including import), processing, distribution, use, and disposal of HBCD, including the following:

  • Importation for manufacturing
  • Processing of flame retardants used in custom compounding of resin
  • Processing of flame retardants used in plastics product manufacturing
  • Recycling of foam and resin panels
  • Building and construction materials
  • Automobile replacement parts
  • Recycled plastics
  • Disposal of construction and demotion waste

In June 2017, EPA released the scope document for HBCD which includes the hazards, exposures, conditions of use, and the potentially exposed or susceptible subpopulations EPA expected to consider in its risk evaluation of the HBCD conducted pursuant to TSCA Section 6(b)(4). In June 2018, EPA released the problem formulation for HBCD which refined the scope of the HBCD risk evaluation by clarifying the chemical uses that EPA expected to evaluate and described 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.

Draft Risk Evaluation

On June 28, 2019, EPA released the draft risk evaluation for HBCD. The public comment period for the draft risk evaluation has closed. 

Review Prior to the Lautenberg Act

Prior to the Lautenberg Act, EPA began the review of the HBCD cluster and published the following information.