Court Rebukes EPA’s Methylene Chloride Approach—And Industry Takes Notice

On September 15, 2026, the U.S. Court of Appeals for the Fifth Circuit vacated EPA’s 2024 methylene chloride (MC) risk management rule and underlying unreasonable-risk determination in East Fork Enterprises v. EPA. Finding legal errors and conclusions unsupported by substantial evidence, the court remanded the matter to EPA, overturning restrictions that would have prohibited many MC uses while permitting certain industrial uses under the Workplace Chemical Protection Program (WCPP).

A Significant Win for Exposure-Based Risk Assessment

Many industry stakeholders view the decision as a victory for science-based, exposure-driven regulation that gives greater consideration to actual workplace conditions, engineering controls, PPE, and documented risk management practices. At the same time, the vacated rule drove substantial compliance investments aimed at meeting EPA’s Existing Chemical Exposure Limit (ECEL) of 2 ppm, an occupational exposure limit approximately 12.5 times lower than OSHA’s 25 ppm PEL.

In the big picture, however, this court’s decision ruling highlights longstanding industry concerns about how EPA has been implementing TSCA risk evaluations and risk management rules. Let’s dig in.

1. Reconsideration of Existing TSCA Risk Evaluations and Rules: The court rejected EPA’s “whole chemical” approach, holding that risk determinations must be made for specific conditions of use. Other TSCA evaluations and risk management actions that relied on similar reasoning may face revision, reconsideration, or legal challenge.
2. Greater Recognition of Workplace Controls The Fifth Circuit concluded that EPA improperly excluded PPE from its unreasonable risk analysis. Future risk evaluations may need to give greater weight to actual workplace practices, including engineering controls, respiratory protection programs, exposure monitoring, and OSHA-compliant PPE requirements. A mature industrial hygiene program provides compelling data to demonstrate risk reduction through existing controls.
3. Higher Evidentiary Burden for EPA Historically, EPA’s Sustainable Futures program provided industry with training on tools such as ECOSAR, EPI Suite, ChemSTEER, and E-FAST, giving companies greater insight into how EPA evaluated chemical hazards, exposures, and risks. As these training opportunities diminished, visibility into EPA’s assumptions and methodologies became more limited, making regulatory outcomes increasingly difficult to predict. The Fifth Circuit’s emphasis on substantial evidence and scientifically supported decisions may renew calls for greater transparency and stakeholder access to the tools and methods that underpin EPA’s risk evaluations.
4. Delays to Future Risk Management Rules EPA’s challenge is no longer just meeting statutory deadlines. The agency must simultaneously advance a growing portfolio of risk evaluations and risk management rules while defending its decisions in court. The MC ruling may improve the scientific rigor and transparency of future TSCA actions, but it could also require EPA to revisit existing evaluations and regulatory frameworks, further extending timelines. For industry, early engagement, robust exposure data, and greater regulatory predictability will be essential.
5. Increased Importance of Exposure Data This ruling is incentive for companies to develop robust occupational exposure monitoring data, industrial hygiene records, and documentation of control measures. If EPA must evaluate risk on a condition-of-use basis and account for actual workplace protections, facility-specific exposure information will become more influential.

How Trinity Can Help

Trinity Consultants helps companies evaluate the implications of evolving TSCA risk evaluations and risk management requirements, including chemical applicability reviews, occupational exposure assessments, industrial hygiene monitoring, evaluation of engineering and administrative controls, PPE and respiratory protection programs, and development of documentation to support facility-specific conditions of use and exposure scenarios.

With the Fifth Circuit’s decision creating new questions around EPA’s approach to TSCA risk evaluations and risk management, companies that manufacture, process, use, or rely on MC or other chemicals undergoing TSCA review should take this opportunity to evaluate their exposure data, workplace controls, and supporting documentation.

If your operations may be affected by the MC decision or other ongoing TSCA risk management actions, early review can help identify potential impacts and position your organization to respond as EPA determines its next steps.

If you would like to discuss how this decision may affect your operations, please email Anne Chappelle at [email protected].