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Assessing and Managing Chemicals under TSCA

Final Risk Evaluation for Cyclic Aliphatic Bromide Cluster (HBCD)

As part of EPA’s mission to protect human health and the environment, the agency has completed a final risk evaluation for HBCD under the Toxic Substances Control Act (TSCA). In the final HBCD risk evaluation, EPA reviewed 12 conditions of use, including as a flame retardant in building materials, solder paste, recycled plastics, and automobile replacement parts.

The HBCD risk evaluation contains the agency’s final determinations on which conditions of use present unreasonable risks to human health or the environment based on a robust review of the scientific data. To prepare the final risk evaluation, EPA reviewed extensive scientific literature, conducted modeling and other risk assessment activities, and collected toxicity, exposure, and hazard information from many sources.

Releasing a final risk evaluation is the last step in the scientific evaluation process required by TSCA and will guide the agency’s efforts to reduce harmful human exposure to this chemical. 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.

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Risk Evaluation Findings

In the September 2020 final risk evaluation, EPA reviewed the exposures and hazards of HBCD uses and made the following final risk findings on this chemical. This final risk evaluation includes input from the public and peer reviewers as required by TSCA and associated regulations. In making these unreasonable risk determinations, EPA considered the hazards and exposure, magnitude of risk, exposed population, severity of the hazard, uncertainties, and other factors.

EPA found no unreasonable risks to the general population. The general population could be exposed to HBCD either through releases to water and air, through waste disposal, or aggregate general background exposure to HBCD not related to any particular use of the chemical. EPA found no unreasonable risks to the general population from releases to air and water, including drinking water.

EPA found no unreasonable risks to consumers. HBCD does not pose an unreasonable risk for use of consumer articles and products or where distributed in commerce. No bystanders were identified for HBCD.

EPA found unreasonable risks to the environment from six conditions of use.  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 the import, processing, recycling, commercial use, consumer use, and disposal of HBCD presents unreasonable risks to the environment.

EPA found unreasonable risks to workers and occupational non-users from the use and disposal of HBCD in building and construction materials. EPA found unreasonable risks to workers and occupational non-users from the use of HBCD in building and construction materials like insulation. Unreasonable risks to workers and occupational non-users can come from both short- and long-term inhalation exposure when personal protective equipment (such as respirators) is not used.

Using Products Safely and Alternatives

While EPA is working through the process required by TSCA to address the unreasonable risks found from HBCD, the information below provides ways to reduce exposure.

For any chemical product, EPA strongly recommends that users carefully follow all instructions on the product’s label. For example, labels on products containing HBCD may state that the product should be used only with adequate ventilation. The labels may also instruct users to move to fresh air if they feel unwell and contact their physician.

Workers using products containing HBCD should continue to follow label instructions and applicable workplace regulations and should properly use appropriate personal protective equipment.

Next Steps and Public Participation

The next step in the process required by TSCA is risk management. EPA will propose and take public comments on actions to address the unreasonable risks identified in the risk evaluation. According to TSCA, the agency must finalize those actions within two years of completing the final risk evaluation. EPA’s proposed regulations could include requirements on how the chemical is used, or limiting or prohibiting the manufacture, processing, distribution in commerce, use, or disposal of this chemical substance, as applicable.

EPA is committed to being open and transparent as the agency follows the process required by the law for evaluating unreasonable risks from chemicals. EPA will continue to keep the public updated as the agency moves through the risk management process. By following the comprehensive risk evaluation process required by TSCA ensures that EPA has confidence in our final conclusions about whether a chemical substance poses any unreasonable risks to health or the environment under the conditions of use. This then allows the public to have confidence in the risk management actions taken to ensure the safety of chemicals on the market.

There will be additional opportunities for public participation. Just like the risk evaluation process, there will be opportunities for public comment as EPA works to propose and finalize risk management actions for HBCD. You can stay informed by signing up for our email alerts or checking the public docket at EPA-HQ-OPPT-2019-0237 at 

Final Risk Evaluation and Supporting Documents

Below are the final risk evaluation for HBCD, non-technical summary, response to comments, and other supporting documents.

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