The Environmental Protection Agency must revoke all tolerances for chlorpyrifos or modify them to meet a federal food safety law, the Ninth Circuit Court of Appeals ruled Thursday.

The insecticide, which has been under fire for more than a decade because of its neurotoxic effects, especially on infants and children, has increasingly been the subject of state bans, including in California, in the absence of federal action. Major manufacturer Corteva Agriscience said last year it would stop making the insecticide at the end of 2020.

Former EPA Administrator Scott Pruitt in early 2017 allowed its continued use despite not making a safety finding, which the court in its decision described as a “delay tactic.”

“EPA has spent more than a decade assembling a record of chlorpyrifos’s ill effects and has repeatedly determined, based on that record, that it cannot conclude, to the statutorily required standard of reasonable certainty, that the present tolerances are causing no harm,” the court said in a 2-1 decision.

“Yet, rather than ban the pesticide or reduce the tolerances to levels that the EPA can find are reasonably certain to cause no harm, the EPA has sought to evade, through one delaying tactic after another, its plain statutory duties,” the court said. The Federal Food, Drug and Cosmetic Act “permits no further delay.”

Specifically, EPA will have 60 days from the issuance of the court mandate implementing the decision to either revoke or modify the tolerances. The court also ordered EPA “to correspondingly modify or cancel related FIFRA registrations for food use in a timely fashion” in accordance with the law.

“The court got it right: EPA’s time is now up,” said Patti Goldman, managing attorney at Earthjustice, who litigated the case for environmental and farm labor groups. “EPA must now follow the law, ban chlorpyrifos, and protect children and farmworkers from a pesticide we know is linked to numerous developmental harms.”

The New York Attorney General’s Office also hailed the decision, with Attorney General Letitia James calling it a “major victory.” The state led a coalition of nine attorneys general challenging EPA’s decision to allow use of chlorpyrifos while EPA’s registration review continues through 2022.

The court said based on the record, “the only reasonable conclusion the EPA could draw is that the present tolerances are not safe within the meaning of the FFDCA. The EPA can find a tolerance safe only if there is ‘a reasonable certainty’ of ‘no harm,’ and for nearly a decade, the EPA and its [Scientific Advisory Panels] have concluded that there is not a reasonable certainty of no harm.”

The decision was written by U.S. District Judge Jed Rakoff of the Southern District of New York, sitting by designation, He was joined by Circuit Judge Jacqueline H. Nguyen. Dissenting was Circuit Judge Jay Bybee, who, while criticizing EPA “dithering,” nonetheless said EPA’s decisions were within the law.

“The question EPA had to answer in this proceeding is whether new scientific evidence is sufficient to require EPA to ‘modify or revoke’ its prior determination,” Bybee said. “Under the FFDCA, EPA must do so ‘if the Administrator determines it is not safe.’… Because EPA found that chlorpyrifos was safe when it concluded its prior rulemaking in 2006, EPA properly determined here that there was insufficient evidence to conclude that chlorpyrifos is ‘not safe’ and thus it was not required to ‘modify or revoke’ those tolerances.”

The majority, however, called Bybee’s reading “strained” and quoted the FFDCA, which says, “The Administrator may establish or leave in effect a tolerance for a pesticide chemical residue in or on a food only if the Administrator determines that the tolerance is safe. The Administrator shall modify or revoke a tolerance if the Administrator determines it is not safe.”

“We think that these two simple sentences are — with their emphasis on the word ‘only’ — remarkably straightforward,” the opinion said.

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An EPA spokesperson said the agency is "reviewing the decision as it considers its options." The statement continued, "As the agency pursues its mission to protect human health, including that of children, and the environment, EPA is committed to ensuring the safety of pesticides and other chemicals. The agency is committed to helping support and protect farmworkers and their families while ensuring pesticides are used safely among the nation’s agriculture. EPA will continue to use sound science in the decision-making process under the Federal Insecticide, Fungicide and Rodenticide Act.” 

Corteva Agriscience said that although it no longer produces chlorpyrifos, "we are disappointed in this outcome, which threatens to effectively remove an important tool for farmers. The ruling disregards a robust database of more than 4,000 studies and reports that have examined the product in terms of health, safety and the environment."

Agri-Pulse also reached out for comment to CropLife America and the American Farm Bureau Federation, but did not immediately receive reaction to the decision.

Dozens of farm groups filed an amicus brief in the appeals court siding with EPA, arguing that chlorpyrifos is safe to use and important to control pests in a wide variety of crops.

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