EPA and FDA Update Chlorpyrifos Regulations and Guidelines in Response to Eighth Circuit Ruling

On February 5, 2024, the U.S. Environmental Protection Agency (EPA) and U.S. Food and Drug Administration (FDA) updated their respective regulations and published guidance concerning chlorpyrifos residues in response to a ruling from the U.S. Court of Appeals for the Eighth Circuit. The updates reflect the Eighth Circuit’s rejection of EPA’s 2021 rulemaking that revoked all tolerances for chlorpyrifos under the Federal Food, Drug, and Cosmetic Act (FDCA).

The Eighth Circuit’s holding largely returned the regulatory scheme to its pre-2021 rulemaking status. That holding took effect on December 28, 2023, meaning that, with limited exceptions, industry actors can evaluate chlorpyrifos residue issues today just as they did before EPA’s 2021 rulemaking. That said, EPA recently announced plans to promulgate a new rule, which would revoke all chlorpyrifos tolerances, with eleven exceptions. Thus, companies interested in the future of chlorpyrifos should consider engaging with EPA on this issue, including by commenting on any proposed rule that would revoke chlorpyrifos tolerances.

Under the Federal Insecticide, Fungicide, Rodenticide Act (FIFRA), EPA can register a pesticide—thus authorizing its use—if it determines that the pesticide will not unreasonably harm humans or the environment.[1] The FDCA in turn bars pesticide chemical residue in or on foods sold in interstate commerce unless EPA promulgates a tolerance or an exemption for that chemical.[2] Tolerances are fact-specific and turn on EPA’s assessment of the health and safety risks posed by a given residue on a given food at a given level, and “a separate tolerance (or exemption) must be established for each pesticide-food combination.”[3] While EPA sets the tolerances, FDA is responsible for enforcement of those tolerances in FDA-regulated foods.

EPA first registered chlorpyrifos under FIFRA in 1965, and farmers have used pesticides containing chlorpyrifos since then. The agency has revisited its chlorpyrifos regulations numerous times over the last sixty years, including the chemical’s FDCA residue tolerances, many of which date back decades. EPA’s actions (and inactions) concerning chlorpyrifos have attracted significant commentary and litigation from both agricultural and environmental groups. In response to one such lawsuit challenging chlorpyrifos tolerances, the U.S. Court of Appeals for the Ninth Circuit in 2021 ordered EPA “either to modify chlorpyrifos tolerances and concomitantly publish a finding that the modified tolerances are safe, including for infants and children—or to revoke all chlorpyrifos tolerances,” within sixty days of the court’s ruling.[4]

Citing the Ninth Circuit’s decision, EPA, on August 27, 2021, promulgated a rule revoking all tolerances for chlorpyrifos.[5] The rule took effect on October 29, 2021, and specified that all chlorpyrifos tolerances would expire by February 28, 2022. Three chlorpyrifos registrants accepted EPA’s rulemaking and voluntarily cancelled or amended their registrations, while other agricultural companies and groups filed objections with EPA, all of which EPA denied.[6] Entities who objected then sought review in the Eighth Circuit of both EPA’s rule and its denial of their objections.

In response to EPA’s rulemaking, FDA’s Center for Food Safety and Applied Nutrition (CFSAN), which regulates human food, published guidance clarifying the agency’s approach to chlorpyrifos residues in FDA-regulated human foods.[7] CFSAN announced that it would follow its longstanding “Channels of Trade” policy and allow the sale of human foods bearing chlorpyrifos residues so long as the chlorpyrifos use was lawful at the time of application. Because EPA specified that all chlorpyrifos tolerances would expire on February 28, 2022, CFSAN determined that the last lawful application date for chlorpyrifos was February 27, 2022. Moreover, CFSAN announced a two-stage planned enforcement approach, under which it first would exercise enforcement discretion for human foods by not requesting documentation showing that the application of chlorpyrifos to a commodity crop was lawful for a period ranging from six to twenty-four months after February 27, 2022 depending on the specific food commodity at issue. In addition, CFSAN explained that it generally would not take enforcement action during this same period on the basis of the presence of chlorpyrifos residues in a human food as long as the residue was within the former tolerance. After the enforcement discretion period, CFSAN would request documentation demonstrating that residues present in human foods were the result of lawful application or use of chlorpyrifos.

The FDA Center for Veterinary Medicine (CVM), which regulates food for animals, did not publish a formal policy regarding chlorpyrifos, but advised in private correspondence that it decided not to issue guidance for each commodity and instead to evaluate each situation on a case-by-case basis. Similarly to CFSAN, CVM applied the Channels of Trade provision in the FDCA[8] to exercise enforcement discretion for animal foods such that, as long as the pesticide had been applied legally prior to February 28, 2022 and the level detected was below the applicable tolerance at that time, CVM would not consider the food to be adulterated. Otherwise, it would consider any quantifiable chlorpyrifos residue detected on animal foods after February 28, 2022, to be violative.

On November 2, 2023, a three-judge panel unanimously ruled against EPA, determining that its tolerance-revocation rule and denial order were arbitrary and capricious.[9] In reaching this conclusion, the court cited a proposed interim decision published by EPA in December 2020.[10] In that decision, EPA identified eleven “high-benefit chlorpyrifos uses” that were likely safe, provided that EPA revoked all other chlorpyrifos tolerances. Those use cases span the country and include certain applications of chlorpyrifos to alfalfa, apples, asparagus, cherries, citrus, cotton, peaches, soybeans, strawberries, sugar beets, and wheat.

Despite knowing about these use cases, EPA did not specifically refer to them in its 2021 revocation rulemaking, instead concluding that the Ninth Circuit left it with no choice but to revoke all tolerances. The Eighth Circuit found this conclusion arbitrary and capricious. Thus, the Eighth Circuit vacated EPA’s revocation rule and denial order and remanded the matter to EPA, ordering the agency to “at least recognize the full scope of what it can do before announcing what it will not do.” The court’s mandate issued on December 28, 2023, finalizing its judgment and formally vacating EPA’s rule and denial.

On February 5, 2024, EPA and CFSAN updated their respective regulations and guidelines to accord with the Eighth Circuit’s decision. EPA promulgated a rule on February 2 (which took effect on February 5) effectively removing its revocation rule from the Code of Federal Regulations, thus reinstating the various chlorpyrifos tolerances.[11] And CFSAN withdrew the guidance document discussed above. [12]

For now, the Eighth Circuit’s decision has largely reinstated the pre-2021 rulemaking status quo, meaning that the various chlorpyrifos tolerances are back in force (not just the eleven that the Eighth Circuit highlighted). Thus, most agricultural firms and food companies can address chlorpyrifos residues today much as they treated them prior to the 2021 revocation rule.

Companies should, however, be aware that FIFRA registration cancellations and modifications remain in place: Following EPA’s revocation rule, three companies—ADAMA US; Corteva Agriscience, LLC; and Winfield Solutions, LLC—voluntarily requested cancellations of or amendments to their FIFRA registrations for chlorpyrifos-containing pesticides. EPA accepted those requests on May 3, 2023, when it cancelled the registrations of fourteen products and amended the registrations of three products.[13] Those cancellations and modifications remain the law today, such that companies must ensure compliance with those registrations or modifications when using chlorpyrifos.

Moreover, EPA has publicly announced its intentions to pursue a new chlorpyrifos rulemaking soon. Specifically, the agency “expects to expeditiously propose a new rule to revoke the tolerances associated with all but the 11 uses referenced by the court.” In the meantime, EPA is currently “engaged in discussions with the registrants to further reduce exposures in specific geographic locations and at specific application rates associated with these 11 uses of chlorpyrifos to address safety of the tolerances.” The precise timeline for the new rulemaking remains unclear, but companies growing or selling products that fall outside those eleven use cases should considering engaging with EPA regarding the future of chlorpyrifos tolerances.