On May 3, 2023, EPA released its proposed risk management rule under Section 6(a) of the Toxic Substances Control Act (TSCA) to impose restrictions on the manufacture, import, processing, distribution, and use of methylene chloride, a widely-used solvent in a variety of consumer and commercial applications. This is the first risk management rule proposed by EPA since it issued revised risk determinations last year based on its new “whole chemical approach” and policy for assuming that personal protective equipment (PPE) is not used by workers. It also reflects a substantial expansion of the regulatory prohibitions applicable to a chemical that was already subject to TSCA risk management restrictions, albeit more limited ones, under EPA’s prior framework for risk management actions.
EPA is proposing to prohibit the manufacture, processing, and distribution in commerce of methylene chloride for consumer use; prohibit most industrial and commercial uses of methylene chloride; require a workplace chemical protection program (WCPP) for certain identified conditions of use that are allowed to continue; and provide certain time-limited, critical use exemptions under Section 6(g) of TSCA for uses of methylene chloride that would otherwise significantly disrupt national security and critical infrastructure. Stakeholders have until July 3, 2023 to comment on the proposed rule.
Proposed Prohibitions on Methylene Chloride Uses
In proposing risk management actions for methylene chloride, EPA found that several consumer, commercial, and industrial uses of the substance require regulatory action, predominantly a prohibition on use, as shown in Table 3 of the proposed rule. Many of these conditions of use include, but are not limited to, industrial and commercial use of methylene chloride in solvents for cleaning, paints and coatings (and removers), vapor degreasing, adhesives, sealants, caulks, textiles and fabrics, automotive care products, lubricants and greases, pipe insulations, oil and gas drilling, toys, playground and sporting equipment, and plastic and rubber products. EPA also identified the need for a prohibition for all consumer uses of methylene chloride that were evaluated.
EPA asserts that the requirements in this proposal would prohibit uses that account for approximately one-third of the total annual production volume of methylene chloride generated (TSCA and non-TSCA uses), “leaving a sufficient supply in circulation to provide a source for these critical or essential uses for which EPA is proposing to allow continued use” either through a critical use exemption or a WCPP.
Timeline for Risk Management Actions
Once EPA finds during risk evaluation that a substance presents an unreasonable risk of injury to human health or the environment, it is required to propose risk management requirements to the extent necessary so that the substance no longer presents such risk. In issuing risk management restrictions on a chemical, EPA must factor in considerations such as the economic consequences of the rule, including consideration of costs and benefits, cost-effectiveness, and the impact of the rule on the economy, small business, and technological innovation. EPA is also required to consider whether technically and economically feasible alternatives will be available as substitutes when banning a use of a substance.
EPA has proposed the following prohibitions on the use of methylene chloride and timelines for the prohibitions to take effect:
EPA also proposes downstream notification requirements for companies who ship methylene chloride to customers and recordkeeping requirements.
The use of methylene chloride in paint and coating removal for consumer use is not included in the listed prohibitions because this use is already addressed by an existing risk management rule promulgated by EPA in 2019, codified at 40 C.F.R. § 751.101.
Critical Use Exemptions (Time-Limited Exemptions)
Section 6(g) of TSCA allows EPA to exempt from the requirement of a risk management rule specific uses that EPA finds to be critical or essential uses for which no technically and economically feasible safer alternative is available or provide a substantial benefit as compared to reasonably available alternatives. It also allows exemption if EPA finds that compliance with the requirement would significantly disrupt the national economy, national security, or critical infrastructure. EPA proposes critical use exemptions for the following conditions of use of methylene chloride:
Ten Conditions of Use Allowed to Continue but Subject to WCPP Requirements
EPA’s proposed WCPP for allowed uses of methylene chloride includes comprehensive requirements for the protection of workers from exposures, including respiratory protection, use of PPE, exposure monitoring, training, and regulated areas. Of note, EPA proposes an Existing Chemical Exposure Limit (ECEL) for airborne concentrations of methylene chloride in excess of 2 parts per million (ppm) based on an 8-hour time weighted average (TWA), which is significantly lower than the current OSHA permissible exposure limit (PEL) for methylene chloride of 25 ppm. The proposed action level would be a value half of the ECEL that would trigger additional monitoring action to ensure workers are not exposed to concentrations above the ECEL. EPA also proposes a short-term exposure limit (EPA STEL) of 16 ppm as determined over a sampling period of 15 minutes.
EPA proposes, in lieu of prohibitions, worker protection requirements for the following conditions of use:
- Manufacturing (for downstream uses that would continue under WCPP)
- Import (for downstream uses that would continue under WCPP)
- Processing: As a reactant. Note that EPA is allowing this use to continue under WCPP because it believes a large volume of methylene chloride is processed for this condition of use, which almost entirely goes towards the manufacture of the hydrofluorocarbon HFC-32. HFC-32 is one of the regulated substances that are subject to a phasedown under the American Innovation and Manufacturing Act (AIM Act) of 2020. EPA expects that, by allowing for the continued, controlled use of methylene chloride in the manufacture of HFC-32, efforts to shift to chemicals with lower global warming potential would not be impeded by this rulemaking.
- Processing: Incorporation into a formulation, mixture, or reaction product
- Processing: Repackaging
- Processing: Recycling
- Industrial and commercial use as a laboratory chemical
- Industrial or commercial use for paint and coating removal from safety-critical, corrosion-sensitive components of aircraft and spacecraft that are owned or operated by the US DOD, NASA, DHS, and FAA that is performed by the agency or the agency’s contractor at locations controlled by the agency or the agency’s contractor
- Industrial or commercial use as a bonding agent for acrylic and polycarbonate in mission-critical military and space vehicle applications, including in the production of specialty batteries for applications that are performed by the DOD, NASA or DHS or their contractors at locations controlled by the agency or the agency’s contractor
Key Considerations of Proposed Rule
Stakeholders who manufacture, process, distribute, or otherwise use methylene chloride for any of the conditions of use evaluated by EPA will likely be interested in commenting on many aspects of this precedent-setting proposed rule. Stakeholders may consider providing input to EPA in the following areas:
- Risk management approach for the conditions of use evaluated: Stakeholders may wish to evaluate whether the proposed risk management requirements proposed for each condition of use are consistent with EPA’s findings from its risk evaluation of methylene chloride for each condition of use and EPA’s statutory authority under Section 6 of TSCA. For example, if EPA found that unreasonable risk is driven by dermal exposures to methylene chloride from a particular condition of use, and if EPA requires more than dermal protection to mitigate the risks, stakeholders may wish evaluate whether such additional requirements are appropriate.
- Costs: EPA estimates that the incremental, non-closure-related costs of this proposed rule are $13.2 million annualized over 20 years at a 3 percent discount rate and $14.5 million annualized over 20 years at a 7 percent discount rate. Stakeholders may wish to evaluate whether these projected costs appropriately include all aspects of implementation of the proposed rule, including the costs for reformulating (for banned uses) or compliance with WCPP for conditions of use permitted to continue, including compliance with the 2 ppm ECEL.
- WCPP requirements: For conditions of use which EPA proposes to prohibit, stakeholders may evaluate whether they have data to support that compliance with a WCPP would sufficiently reduce exposures rather than a prohibition (in particular, for the conditions of use for which EPA proposes a WCPP as an alternative to a ban in the primary alternative option provided in the proposed rule). Stakeholders may also wish to evaluate the feasibility of the WCPP requirements and consider consistency with OSHA’s methylene chloride standard.
- Timelines: Stakeholders may consider whether the proposed timelines for bans are feasible and whether other uses are appropriate for consideration for a time-limited critical use exemption based on the statutory criteria for critical use exemptions.
- Alternatives: Stakeholders may want to comment on EPA’s alternatives assessment for methylene chloride and whether the proposed prohibited uses under the rule have available, safer alternatives to transition to.
- De minimis level: EPA specifically requests comment regarding the number of entities that could potentially go out of business, as well as associated costs, with a prohibition on methylene chloride for certain industrial and commercial conditions of use identified in the proposed rule. EPA would also like comment on whether it should consider a de minimis level of methylene chloride in formulations for certain continuing industrial and commercial uses to account for impurities (e.g., 0.1% or 0.5%) when finalizing the prohibitions, and, if so, what level should be considered de minimis.
- Certification and training: EPA explains in the proposal that it also examined the extent to which a certification and limited access program restricting methylene chloride use to trained and licensed users could ensure that only certain workers employed by a facility would be able to purchase and use methylene chloride. Stakeholders may wish to comment on whether a certification and training program would effectively reduce exposures to workers as a risk management approach for certain conditions of use, including conditions of use that EPA is proposing to ban.