The Environmental Protection Agency is standing by its decision to revoke all chlorpyrifos tolerances, clearing the way for a court to decide whether to allow continued use of the insecticide.

In August, EPA issued its final rule revoking all tolerances, which goes into effect Feb. 28. The chemical has been used on a wide variety of crops, including soybeans, fruit and nut trees, broccoli, cauliflower, sugarbeets and other row crops. However, “It has been found to inhibit an enzyme, which leads to neurotoxicity, and has also been associated with potential neurodevelopmental effects in children,” the agency said in a news release.

"Today’s action shows how EPA continues to put the health and safety of the public first, particularly that of children and farmworkers,” said Assistant Administrator for the Office of Chemical Safety and Pollution Prevention Michal Freedhoff. “After more than a decade of studying a large body of science, EPA is taking the next step towards the cancellation of the use of chlorpyrifos on food.”

EPA’s decision "reaffirms that the law and the science compel revocation of chlorpyrifos food tolerances in order to protect children from learning disabilities and other neurodevelopmental harm," said Patti Goldman, an attorney with Earthjustice who is representing environmental groups and farmworkers who won a case in the U.S. Court of Appeals for the Ninth Circuit, compelling EPA to revoke the tolerances.

The grower groups said the decision "comes as no surprise."

"The agency indicated in its court filings it had every intention of rejecting our objections, hearing requests, and stay requests," they said in a statement. "It’s unfortunate EPA sat on these objections for months and waited until the 11th hour to respond in an attempt to deny agricultural groups any recourse and seal the significant, irreparable harms growers and co-ops will experience under the rule.

"We will review EPA’s rejection decision but fully expect to find more flawed reasoning and legal gymnastics to defend the agency’s decision not to follow the law and ignore safety findings of EPA’s career scientists. We will also continue to pursue our legal challenge and stay request to obtain relief from this harmful, unfounded rule."

EPA said for registrations not voluntarily canceled, “EPA intends to issue a Notice of Intent to Cancel under the Federal Insecticide, Fungicide and Rodenticide Act (FIFRA) to cancel registered food uses of chlorpyrifos associated with the revoked tolerances.”

Grower groups and chlorpyrifos registrant Gharda Chemicals formally objected to the tolerance revocation decision and sought a stay from EPA. They subsequently filed a petition in the U.S. Court of Appeals for the Eighth Circuit seeking an emergency stay of the decision.

The filing of what EPA calls a “final order,” which also denies the grower groups’ request for a stay and hearings, means the court can now rule on the request for an emergency stay, lawyers for the petitioners said in a letter to the court Thursday.

In its letter to the court, EPA said “parties seeking judicial review of EPA’s final order may file petitions for review two weeks after it is published in the Federal Register,” which is scheduled for Monday, Feb. 28.

In its order, EPA said the Federal Food, Drug and Cosmetic Act requires the agency to determine that “there is a reasonable certainty that no harm will result from aggregate exposure to the pesticide chemical residue, including all anticipated dietary exposures and all other exposures for which there is reliable information.”

“Congress understood the phrase ‘aggregate exposure’ to include dietary exposures under all tolerances for the pesticide chemical residue,” EPA said.

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The grower groups have argued that EPA should have continued to allow 11 so-called “safe uses” that EPA identified in a proposed registration decision. But EPA contended in its appeals court filing that the proposal was made under FIFRA, a separate law.

In court, EPA said it “never formally concluded that the 11 uses are safe,” but that it had proposed continuing to allow those uses “under a different statute.”

“In demanding that EPA retain tolerances for the 11 uses, the objectors essentially argue that EPA should have presumed that individuals would only be exposed to chlorpyrifos from the 11 uses because EPA proposed those 11 uses as an option for mitigation” in the 2020 proposal, EPA said. “However, that argument ignores the premise in the [Proposed Interim Decision] that the safety finding for those uses is contingent on all other uses being cancelled and the remaining 11 uses being restricted both geographically and with lowered use rates.”

“Exposures from those uses alone could not reasonably be considered as ‘anticipated’ since they did not yet (nor did EPA have reason to believe that they would) reflect the exposures people would be exposed to in the real world,” EPA said. “The FFDCA requires EPA to determine whether tolerances are safe, requiring consideration of aggregate exposures, including ‘anticipated dietary exposures’; it does not allow EPA to leave tolerances in place if they would be safe at some unspecified time in the future based on certain mitigation that may not be implemented.”

The tolerance revocation was made in response to a U.S. Court of Appeals for the Ninth Circuit decision that ordered EPA to modify or revoke the tolerances. The grower groups have emphasized that EPA could have modified the tolerances, but in its order announced Friday, the agency noted that the court had told EPA to act “immediately” and not conduct “further factfinding.”

“Given the limited window for issuing the rule and the court’s directive not to engage in additional fact-finding or further delay, the agency focused in its rulemaking on the data and completed assessments available at the time and whether they were adequate to support a safety finding for the chlorpyrifos tolerances,” EPA said. “EPA did not conduct additional analyses or engage in any additional fact-finding or scientific review, due to the limited time. Thus, the rule was based on available information that EPA had already reviewed and incorporated into risk assessments and/or regulatory documents.”

This story has been updated to include comments from the grower groups and Earthjustice attorney Patti Goldman.

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