The U.S. Environmental Protection Agency (EPA) issued a proposed rule on August 8, 2024, to address the unreasonable risk of injury to human health presented by 1-bromopropane (1-BP) under its conditions of use (COU) as documented in EPA’s August 2020 Risk Evaluation for 1-BP and the December 2022 Revised Risk Determination for 1-BP prepared under the Toxic Substances Control Act (TSCA). 89 Fed. Reg. 65066. To address the identified unreasonable risk, EPA proposes requirements to, among other things, prevent consumer access to 1-BP, restrict the industrial and commercial use of 1-BP while also allowing for a reasonable transition period where an industrial and commercial use of 1-BP is being prohibited, and protect workers from the unreasonable risk of 1-BP while on the job. EPA will hold a webinar on August 28, 2024, to provide an overview of the proposed rule. Comments are due September 23, 2024. EPA states that under the Paperwork Reduction Act, “comments on the information collection provisions are best assured of consideration if the Office of Management and Budget (OMB) receives a copy of your comments on or before September 9, 2024.”
According to EPA’s web page on risk management for 1-BP, 1-BP is a solvent that is widely used in cleaning and degreasing operations, spray adhesives, and dry cleaning. 1-BP is also used in insulation for building and construction materials and in the manufacture of other chemicals. EPA states that consumer uses of 1-BP include aerosol degreasers, spot cleaners, stain removers, and insulation.
EPA states that it proposes to protect the public from exposure to 1-BP by banning all consumer uses except in insulation (because EPA determined that this use did not contribute to the unreasonable risk to people). The ban on consumer uses would begin to go into effect within six months after the final rule is published and would come fully into force within 15 months.
EPA also proposes to ban some industrial and commercial uses of 1-BP for which EPA analysis identified safer alternatives. The ban on industrial and commercial uses would begin to go into effect six months after the final rule is published and would come fully into effect within 18 months. The industrial and commercial uses to be prohibited include:
- Dry cleaning, spot cleaning, and stain removers;
- Adhesives and sealants;
- Coin and scissor cleaners;
- Automotive care products used as engine degreasers, brake cleaners, and refrigerant flushes;
- Anti-adhesive agents used for mold cleaning and release products;
- Functional fluids used as refrigerants or cutting oils; and
- Arts, crafts, and hobby materials.
EPA notes that the proposed rule would also require worker protections for several industrial and commercial uses of 1-BP that would continue but which EPA has determined contribute to the unreasonable risk to human health that must be addressed, including its use in vapor and aerosol degreasing, electronics, and electronic and metal products. To continue these uses, non-federal workplaces would need to implement a workplace chemical protection program (WCPP), including an exposure limit, within 12 months. EPA also proposes to require the use of chemical-resistant gloves within six months for some uses for non-federal workplaces, including manufacturing, processing (which includes recycling), and disposal, to protect workers from exposures to 1-BP through the skin. Federal agencies (and federal contractors acting for or on behalf of the federal government) would be required to implement a WCPP and use chemical-resistant gloves within three years.
EPA acknowledges that “[m]any workplaces already employ stringent controls to reduce exposures to 1-BP.” EPA states that for some workplaces, such as those using 1-BP in vapor degreasing, the existing controls “may already sufficiently reduce exposure to meet the inhalation exposure concentration limit proposed in this rulemaking.”
Commentary
The proposed rule is consistent with EPA previous proposed and final rules on other high-priority substances and for this reason offers few surprises. For discussion, see our commentaries on trichloroethylene and methylene chloride dated November 3, 2023, and May 17, 2024, respectively. We focus our discussion on issues on 1-BP that are common with EPA’s risk evaluations on high-priority substances and that raise questions on whether EPA’s risk evaluations and its proposed/final risk management actions comport with the scientific standards under TSCA Section 26 and meet the statutory standard in TSCA Section 6.
In the final risk evaluation for 1-BP (Final 1-BP RE), EPA did not identify unreasonable non-cancer risks to workers with no gloves from acute or chronic dermal exposures. EPA did, however, identify unreasonable cancer risks to workers for all of the high-end exposure scenarios under the assumption of no glove use. We mention this because EPA’s identified unreasonable risks were based on its use of an “Oils study” to inform the quantity of 1-BP remaining on the skin. For discussion, see our memorandum dated July 21, 2022. EPA has been using the “Oils study” for decades with its evaluation of new chemical substances. This study has, however, come under recent scrutiny within EPA. For example, EPA included a charge question to the TSCA Science Advisory Committee on Chemicals (SACC) on the appropriateness of using the “Oils study” to inform its recent draft risk evaluation on 1,1-dichloroethane. For discussion, see our memorandum dated July 19, 2024. The outcome of the SACC review may impact EPA’s use of the “Oils study” in the Final 1-BP RE and its subsequent reliance on this document for its proposed rule, given that 1-BP, like 1,1-dichloroethane, is a volatile organic compound (VOC). It is questionable whether using a highly viscous and non-volatile substance (e.g., cooking oil) is appropriate for informing the amount of a low-viscosity VOC remaining on the skin. Measuring dermal exposures, especially to VOCs, has been a challenge for EPA and industry stakeholders.
As with other risk management rules, we question EPA’s proposal to ban certain COUs when EPA finds a WCPP to be protective. Bergeson & Campbell, P.C. (B&C®) agrees that 1-BP may cause “irreversible health effects (specifically developmental toxicity and cancer)” if exposures are not adequately mitigated under its COUs. For discussion, see our memorandum dated July 21, 2022. As we have in past bans under Section 6, we question EPA’s proposal to prohibit most industrial and commercial uses of 1-BP as satisfying the “extent necessary” provision of TSCA Section 6(a) when EPA finds that compliance with a WCPP protects against the risks identified.
TSCA Section 6(c)(2)(C) states in part that “the Administrator shall consider, to the extent practicable, whether technically and economically feasible alternatives that benefit health or the environment, compared to the use so proposed to be prohibited or restricted ….” (Emphasis added.) EPA continues to be challenged by the complexity of its alternative assessments, especially in cases like 1-BP in which the breadth of uses means that EPA must evaluate a wide range of alternatives. In this case, EPA evaluated adhesives include cyanoacrylates (superglue), solvent adhesives, and caulk — three very different classes of adhesives. EPA proposed to ban, as part of its Proposed Regulatory Action, multiple uses of 1-BP, including as an adhesive in industrial and commercial uses. EPA’s alternatives assessment identified 227 products for the adhesives category. EPA also struggled to find full compositional information for many of the products in the alternatives assessment, making it difficult, if not impossible, for EPA to evaluate whether alternatives “benefit health or the environment.” In addition, EPA has struggled to identify hazard data to support its alternatives assessments. Whether EPA views any of the listed adhesives as an appropriate replacement for 1-BP is not clear.
It is critical that EPA’s alternatives assessments are well-conducted and well-supported so that EPA can meet its obligation to identify “alternatives that benefit health or the environment.” This is especially true when EPA is seeking to ban a substance, since the existence of alternatives is a consideration in EPA’s selection of regulatory options and EPA does not want to invite a regrettable substitution. Without additional information, it is unclear whether EPA’s alternatives assessment of these products meets the requirements of TSCA Section 6(c)(2)(C).
EPA’s approach (banning many COUs) removes the opportunity for workplaces to determine whether compliance with EPA’s WCPP is possible. This fact may drive substitution to alternatives that have unknown, equal, or even greater hazard concerns that are without binding workplace protections.