EPA Cannot Use Low Exposure to Justify DecaBDE Inaction, Ninth Circuit Rules
The Ninth Circuit has ruled that EPA’s decisions not to regulate certain decabromodiphenyl ether (decaBDE) exposures under the Toxic Substances Control Act (TSCA) were not supported by substantial evidence, ordering the agency to regulate or better justify its inaction in four areas: recyclable articles, disposal, wastewater, and sewage sludge.
The May 13, 2026, ruling leaves EPA’s regulations for decaBDE intact but remands them back to agency to regulate—or better defend its decision not to regulate—those areas. It is the first time a court has weighed in on TSCA section 6(h), which requires EPA to reduce exposures to certain persistent, bioaccumulative, and toxic chemicals (PBTs) “to the extent practicable.”
Congress added section 6(h) in 2016. EPA issued a risk management rule for decaBDE in 2021 and amended it in 2024, targeting the flame retardant’s use in products. But the agency declined to regulate various other exposures, citing low exposures and prohibitively high costs.
Siding with environmental groups, the Ninth Circuit rejected EPA’s low-exposure rationale outright. Because TSCA does not require EPA to conduct a risk evaluation before regulating section 6(h) PBTs, Congress already determined that any exposure warrants a regulatory response, the court held.
“[I]t is beyond EPA’s authority to justify a decision not to regulate based on there being low levels of decaBDE,” the opinion states. “TSCA § 6(h)(4) permits EPA to consider decaBDE levels for the purpose of deciding between regulatory tools, but not in deciding whether to use a regulatory tool at all.”
The court stopped short of holding that high costs can never justify a decision not to regulate under section 6(h), but it found EPA’s cost evidence consistently inadequate. For recyclable articles, for example, EPA’s economic analysis relied on studies not specific to decaBDE and failed to consider regulatory options short of an outright ban.
Substantial Evidence
EPA’s other justifications fared no better under TSCA’s “substantial evidence” standard, which the court characterized as a “searching review.”
On disposal, EPA argued regulations were unnecessary because the Resource Conservation and Recovery Act (RCRA) already reduces exposures to the extent practicable. But the court held that “EPA cannot evade its responsibilities under TSCA to regulate decaBDE disposal merely by invoking EPA’s compliance with another statute regulating solid waste disposal,” while also observing that RCRA does not cover all possible disposals.
For wastewater, the court found that EPA had ignored data contradicting its position that decaBDE is not released to water. And, on recycling, it held that the agency gave “undue weight” to its position that regulation would undermine its general pro-recycling stance.
The court also rejected EPA’s fallback argument that staged regulation justifies its current inaction. Section 6(h) “expressly places regulation of decaBDE on an expedited timeline,” the court held, and EPA has made no commitment to address these exposures in future rulemaking.
The case is Alaska Cmty. Action on Toxics v. United States EPA, No. 21-70168 (9th Cir.).
