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June 30, 2022

Final Revision to HBCD Risk Determination Finds HBCD, as a Whole Chemical Substance, Presents an Unreasonable Risk

Bergeson & Campbell, P.C.

The U.S. Environmental Protection Agency (EPA) announced on June 29, 2022, the availability of the final revision to the risk determination for the cyclic aliphatic bromide cluster (HBCD) risk evaluation issued under the Toxic Substances Control Act (TSCA). 87 Fed. Reg. 38747. The revision reflects EPA policy changes intended to ensure the public is protected from unreasonable risks from chemicals in a way that is supported by science and the law. EPA states that it determined that “HBCD, as a whole chemical substance, presents an unreasonable risk of injury to health and the environment when evaluated under its conditions of use.” In addition, the revised risk determination does not reflect an assumption that all workers always appropriately wear personal protective equipment (PPE). According to the notice, EPA “understands that there could be occupational safety protections in place at workplace locations; however, not assuming use of PPE reflects EPA’s recognition that unreasonable risk may exist for subpopulations of workers that may be highly exposed because they are not covered by [Occupational Safety and Health Administration (OSHA)] standards, or their employers are out of compliance with OSHA standards, or because OSHA has not issued a permissible exposure limit (PEL) (as is the case for HBCD).” The revised risk determination supersedes the condition of use-specific no unreasonable risk determinations in the September 2020 HBCD risk evaluation and withdraws the associated order included in Section 5.4.1 of the September 2020 HBCD risk evaluation.

Whole Chemical View of the Unreasonable Risk Determination for the HBCD Risk Evaluation

According to the notice, and as announced on June 30, 2021, EPA plans to consider the appropriate approach for each chemical substance risk evaluation on a case-by-case basis, taking into account considerations relevant to the specific chemical substance in light of EPA’s obligations under TSCA. EPA states that it expects that this case-by-case approach “will provide greater flexibility in the Agency’s ability to evaluate and manage unreasonable risk from individual chemical substances. EPA believes this is a reasonable approach under TSCA and the Agency’s implementing regulations.”

With regard to the specific circumstances of HBCD, EPA states that it determined that a whole chemical approach is appropriate for HBCD to protect health and the environment. According to EPA, the whole chemical approach “is appropriate for HBCD because there are benchmark exceedances for multiple conditions of use (spanning across most aspects of the chemical lifecycle — from manufacturing (import), processing, commercial use, and disposal) for both health and the environment, HBCD is persistent, bioaccumulative and toxic substance, and the health effects associated with HBCD exposures are irreversible.” Because the chemical-specific properties cut across the conditions of use within the scope of the risk evaluation and a substantial amount of the conditions of use drive the unreasonable risk, EPA states that it is appropriate to make a determination for HBCD and that it “has concluded that the whole chemical presents an unreasonable risk.”

For purposes of TSCA Section 6(i), EPA is making a risk determination on HBCD as a whole chemical. Under the revised approach, the “whole chemical” risk determination for HBCD supersedes the no unreasonable risk determinations for HBCD that were premised on a condition-of-use-specific approach to determining unreasonable risk and also contains an order withdrawing the TSCA Section 6(i)(1) order in Section 5.4.1 of the September 2020 HBCD risk evaluation.

Final Revision about the Use of PPE

EPA states that in the risk evaluations for the first ten chemical substances, as part of its unreasonable risk determination, EPA assumed for several conditions of use that all workers were provided and always used PPE in a manner that achieves the stated assigned protection factor (APF) for respiratory protection, or used impervious gloves for dermal protection. In support of this assumption, EPA used reasonably available information such as public comments indicating that some employers, particularly in the industrial setting, provide PPE to their employees and follow established worker protection standards (e.g., OSHA requirements for protection of workers).

For the September 2020 HBCD risk evaluation, EPA assumed that workers used PPE for six of the 12 conditions of use:

  • Manufacturing — Import;
  • Processing: Incorporating into formulation, mixture, or reaction products;
  • Processing: Incorporation into article;
  • Processing: Recycling (of XPS and EPS foam, resin, panels containing HBCD);
  • Processing: Recycling (of electronics waste containing high-impact polystyrene (HIPS) that contains HBCD); and
  • Commercial/Consumer Use: Other — Formulated Products and Articles.

EPA states that it is revising the assumption for HBCD that workers always or properly use PPE, “although it does not question the public comments received regarding the occupational safety practices often followed by industry respondents.” According to the notice, when characterizing the risk to human health from occupational exposures during risk evaluation under TSCA, EPA “believes it is appropriate to evaluate the levels of risk present in baseline scenarios where PPE is not assumed to be used by workers.” EPA states that it should be noted that, in some cases, baseline conditions may reflect certain mitigation measures, such as engineering controls, in instances where exposure estimates are based on monitoring data at facilities that have engineering controls in place. EPA’s approach considers the risk to potentially exposed or susceptible subpopulations of workers who may not be covered by OSHA standards, such as self-employed individuals and public sector workers who are not covered by an OSHA State Plan.

In addition, EPA states that it believes it is appropriate to evaluate the levels of risk present in scenarios considering applicable OSHA requirements (e.g., chemical-specific PELs and/or chemical-specific PELs with additional substance-specific standards), as well as scenarios considering industry or sector best practices for industrial hygiene that are “clearly articulated” to EPA. Consistent with this approach, the September 2020 HBCD risk evaluation characterized risk to workers both with and without the use of PPE. According to EPA, by characterizing risks using scenarios that reflect different levels of mitigation, EPA risk evaluations can help inform potential risk management actions by providing information that could be used during risk management to tailor risk mitigation appropriately to address any unreasonable risk identified, or to ensure that applicable OSHA requirements or industry or best sector practices that address the unreasonable risk are required for all potentially exposed and susceptible subpopulations of workers (including self-employed individuals and public sector workers who are not covered by an OSHA State Plan).

EPA states that when undertaking unreasonable risk determinations as part of TSCA risk evaluations, it does not believe it is appropriate to assume as a general matter that an applicable OSHA requirement or industry practice is consistently and always properly applied, however. According to EPA, the mitigation scenarios included in the EPA risk evaluation (e.g., scenarios considering use of various PPE) “likely represent what is happening already in some facilities.” EPA notes that it “cannot assume that all facilities have adopted these practices for the purposes of making the TSCA risk determination.”

EPA is making a determination of unreasonable risk for HBCD from a baseline scenario that does not assume compliance with OSHA standards, including any applicable exposure limits or requirements for use of respiratory protection or other PPE. EPA notes that making unreasonable risk determinations based on the baseline scenario “should not be viewed as an indication that EPA believes there are no occupational safety protections in place at any location, or that there is widespread non-compliance with applicable OSHA standards. Rather, it reflects EPA’s recognition that unreasonable risk may exist for subpopulations of workers that may be highly exposed because they are not covered by OSHA standards, such as self-employed individuals and public sector workers who are not covered by a State Plan, or because their employer is out of compliance with OSHA standards, or because EPA finds unreasonable risk for purposes of TSCA notwithstanding OSHA requirements.”

In accordance with this approach, EPA prepared its final revision to the HBCD risk determination without relying on assumptions regarding the occupational use of PPE in making the unreasonable risk determination under TSCA Section 6. EPA states that it will consider information on the use of PPE as a means of mitigating risk (including public comments received from industry respondents about occupational safety practices in use) during the risk management phase, as appropriate. As a general matter, when undertaking risk management actions, EPA states that it intends to strive for consistency with applicable OSHA requirements and industry best practices, including appropriate application of the hierarchy of controls, to the extent that applying those measures would address the identified unreasonable risk, including unreasonable risk to potentially exposed or susceptible subpopulations.

Consistent with TSCA Section 9(d), EPA will consult and coordinate TSCA activities with OSHA and other relevant federal agencies “for the purpose of achieving the maximum applicability of TSCA while avoiding the imposition of duplicative requirements.” Informed by the mitigation scenarios and information gathered during the risk evaluation and risk management process, EPA states that it might propose rules that require risk management practices that may be already common practice in many or most facilities. Adopting clear, comprehensive regulatory standards will foster compliance across all facilities (ensuring a level playing field) and ensure protections for all affected workers, especially in cases where current OSHA standards may not apply or be sufficient to address the unreasonable risk.

According to EPA, by removing the assumption of PPE use in making the whole chemical risk determination for HBCD, the same six conditions of use would continue to drive the proposed unreasonable risk determination. The impact of removing the assumption of PPE use, however, would cause four of the six conditions of use that drive the unreasonable risk determination based only on risks to the environment also to drive unreasonable risk based on health risks to workers. The four conditions of use affected by this change are:

  • Manufacturing — Import;
  • Processing: Incorporation into formulation, mixture, or reaction products;
  • Processing: Incorporation into article; and
  • Processing: Recycling (of XPS and EPS foam, resin, panels containing HBCD).

Final Conclusions in the Revised TSCA Risk Evaluation Based on the Whole Chemical Approach and Not Assuming the Use of PPE

EPA determined that HBCD presents an unreasonable risk to health and the environment under the conditions of use. EPA’s unreasonable risk determination for HBCD is driven by risks associated with the following conditions of use, considered singularly or in combination with other exposures:

  • Manufacturing — Import;
  • Processing: Incorporation into a Formulation, Mixture, or Reaction Products;
  • Processing: Incorporation into Article;
  • Processing: Recycling (of XPS and EPS foam, resin, and panels containing HBCD);
  • Commercial/Consumer Use: Building/Construction Materials (Installation); and
  • Disposal (Demolition).

EPA notes that while it assessed commercial and consumer use as part of the same exposure scenario for the “Commercial/Consumer Use: Building/Construction Materials (Installation)” condition of use, it quantified the risks separately and found consumer use did not drive the HBCD unreasonable risk.


EPA’s embrace of the whole chemical approach, and its application to HBCD resulting in a single “unreasonable risk” finding for HBCD, will continue to invite criticism from some, and support from others. Whether it will result in a legal challenge remains to be seen. There are many procedural and substantive issues in play in the final rule, and intuitively, it seems reasonable to assume that EPA will be sued, likely by multiple stakeholders. EPA did an admirable job of responding to industry commenters’ concerns with the procedural aspects of EPA’s shift to the whole chemical approach from use-by-use in the final rule. That said, fundamental due process and TSCA interpretative issues remain unresolved. A raft of other issues, including the relevance of applicable OSHA requirements, EPA’s withdrawal of the no unreasonable risk findings with regard to other conditions of use, the withdrawal’s impact on state HBCD regulations, and the likelihood of litigation of the order withdrawing the findings are also in play. Given the fact this is the first final rule reflecting EPA’s new policies, it would seem litigation is in our future.