Court decision allows chlorpyrifos use to resume, EPA considers next steps

Regulatory approval of chlorpyrifos, an organophosphate insecticide, is one of stops and starts. Since its first use in 1965, it’s been used on crops like corn, wheat, apples, strawberries and citrus under the trade names Dursban and Lorsban. After a brief ban effective February 2022, Environmental Protection Agency (EPA) recently issued its reapproval forcing FDA to withdraw its 2022 guidance document, “Questions and Answers Regarding Channels of Trade Policy for Human Food Commodities with Chlorpyrifos Residues: Guidance for Industry.”

Because of its efficacy against multiple pests, chlorpyrifos is one of the most widely used insecticides in the world. While growers love it, it’s one of the most loathed by environmental groups. Arguably, chlorpyrifos evokes the emotional charge of DDT or glyphosate.

“The Nazis developed organophosphates as nerve agents but did not use them in World War II,” Patti Goldman, senior attorney at Earthjustice, said. “After the breakup of the Nazi state, the emerging chemical companies adapted and formulated organophosphates for commercial pesticide use.“ Chlorpyrifos is one of those commercial pesticides.

Chlorpyrifos’ approved use has been modified over the years. In 2000, for example, it was discontinued on tomatoes and restricted to pre-bloom and dormant applications of apples. In 2002, EPA established buffer zones to protect water quality and wildlife. Application rates were reduced. Health and ecological assessments continued over the years.

In 2007, Natural Resources Defense Council (NRDC) and Pesticide Action Network North America (PANNA) petitioned EPA to revoke all tolerances and cancel all registrations for chlorpyrifos.The request was ignored. Ten years later, EPA denied the petition. That’s when it started to get ugly. Several groups joined NRDC in a lawsuit against EPA.

In 2021, the 9th U.S. Circuit Court of Appeals issued an opinion. “This dispute concerning the documented health risks posed by a widely used pesticide, chlorpyrifos, has been before this Court more than a half-dozen times,” U.S. District Judge Jed S. Rakoff said in the petition denial. “The Environmental Protection Agency (“EPA” or the “Agency”) has recognized that when pregnant mothers are exposed to chlorpyrifos residue, this likely harms infants in utero. Nevertheless, in derogation of the statutory mandate to ban pesticides that have not been proven safe, the EPA has failed to act, requesting extension after extension. The Agency’s present position is effectively more of the same.”

The document continued, “The EPA must act based upon the evidence and must immediately revoke or modify chlorpyrifos tolerances.” In compliance with the court’s order, EPA revoked all tolerances for chlorpyrifos in August 2021.

Several grower groups filed suit against EPA in February 2022, pointing out that EPA ignored the agency’s own scientific analysis in revoking all food tolerances for chlorpyrifos. Congress entered the fray. On Sept. 20, 2022, USDA Secretary Thomas Vilsack disagreed with the decision to ban chlorpyrifos. In a response provided to Congress, Secretary Vilsack stated that the USDA pest management scientists believe EPA could retain certain chlorpyrifos uses that meet EPA’s safety standards.

On Nov. 2, 2023, the 8th U.S. Circuit Court of Appeals heard the case. “This is the latest round in the battle over chlorpyrifos, which has been waged behind the scenes for some time,” the court said. Yet while recognizing that leftover residue can be harmful for humans, it stated that before banning the insecticide altogether, “EPA had set specific tolerances for over a hundred different crops.”

The decision was made that chlorpyriphos tolerances would be in effect again while EPA considers modification of tolerances. On Feb. 5, 2024, EPA issued a final rule to amend the Code of Federal Regulations to reflect the court’s reinstatement of those tolerances.

“The actions the agencies are taking now are simply conforming regulations and guidance to the Eighth Circuit decision,” Goldman said. “Next, EPA will need to decide whether chlorpyrifos is safe for children. In light of the extensive science showing chlorpyrifos causes learning disabilities at low exposure levels, EPA cannot find the pesticide safe and will need to reinstate the food ban.”

California, Hawaii, New York, Maryland and Oregon have their own bans on chlorpyrifos.