The DC Circuit Court has unanimously upheld the EPA’s designation of two widely used chemical compounds as hazardous substances under federal environmental law.
The ruling, handed down on August 18, confirmed the EPA’s classification of perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS) under the Comprehensive Environmental Response, Compensation, and Liability Act, known as CERCLA.
The decision in Chamber of Commerce v. EPA marks one of the most significant shifts in environmental liability for manufacturers and industrial users in recent memory.
For decades, cleanup costs associated with these per- and polyfluoroalkyl substances, commonly known as PFAS, have largely fallen to taxpayers rather than the companies responsible for producing or using them.
That calculation has now changed dramatically, with the ruling unlocking CERCLA’s powerful enforcement tools against the two chemical compounds.
The EPA first designated PFOA and PFOS as hazardous substances in May 2024, citing scientific evidence linking the compounds to cancer, developmental effects, cardiovascular conditions, and other serious health harms.
The DC Circuit’s decision extensively catalogued the many regulatory steps that must occur before cleanup liability can attach to any specific party.
Those steps include Hazard Ranking System scoring, National Priorities List placement through notice-and-comment rulemaking, site investigation, cost-effectiveness analysis, feasibility studies, and settlement procedures.
The court also highlighted CERCLA’s affirmative defences available to companies, including protections for acts of God, third-party acts, de minimis and de micromis exposures, and the innocent landowner defence.
The rejection of constitutional challenges brought by industry groups clears a significant legal hurdle, leaving fewer avenues for companies to contest their potential liability under the statute.
Manufacturers, transporters, waste handlers, and downstream users associated with these chemicals over the past eight decades now face direct exposure to federal cleanup enforcement actions.
Legal analysts say the ruling also sets the stage for the EPA to designate additional PFAS compounds beyond PFOA and PFOS as hazardous substances, using the same regulatory framework upheld by the court.
Companies with exposure to the broader PFAS chemical family are being advised to begin proactive risk assessment and contamination mapping now, rather than waiting for additional designation rulemakings to proceed.
The scale of potential liability is substantial, given how widely PFAS compounds have been used across industries including aerospace, food packaging, firefighting, and consumer goods manufacturing.
With the legal framework now firmly established, businesses facing PFAS-related exposure should treat this ruling as an urgent prompt to review their environmental risk profiles and engage specialist legal counsel without delay.