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Chlorpyrifos returns to the US market

Court overturns ban, orders EPA to review organophosphate insecticide again

by Britt E. Erickson
November 6, 2023

Chemical structure of chlorpyrifos.

In a win for farmers and pesticide makers, a federal appeals court has reopened the door for use of the organophosphate pesticide chlorpyrifos on food crops in some US states.

A Nov. 2 ruling by the US Court of Appeals for the 8th Circuit nixes a 2021 rule issued by the Environmental Protection Agency banning the neurotoxic insecticide on food. The court ruling also orders the EPA to reevaluate whether chlorpyrifos can be safely used on crops like sugar beets, soybeans, and certain fruits and vegetables.

In its opinion, the court notes that the EPA failed to consider “its own proposal to keep a set of high-benefit uses in place.” The EPA was under a short court-ordered deadline to make a decision about whether to cancel all uses of chlorpyrifos on food or show that anticipated uses are safe. The agency zeroed in on a single solution—banning all uses of chlorpyrifos on food—rather than considering whether the pesticide could be safely used on a few select crops, the court ruled.

The battle over chlorpyrifos has been playing out for more than a decade. Environmental groups petitioned the EPA in 2007 to ban the chemical, citing harm to the brains of developing children.

The EPA proposed to ban chlorpyrifos on food in 2015, and after a lot of back-and-forth, finally did so in August 2021, in response to a court order. A year later, farm groups and a chemical manufacturer legally challenged the rule, which the 8th Circuit has now overturned.

Some states, including California, Hawaii, Maryland, New York, and Oregon, have banned chlorpyrifos on food grown and sold in their jurisdictions. Those bans remain in effect.

Earthjustice, an environmental law group that has represented environmental and public health groups in many chlorpyrifos lawsuits, called the latest court ruling shocking.

“We are profoundly saddened by the 8th Circuit’s decision to send the chlorpyrifos ban back to the EPA to review, which will subject farmworkers and children to this extremely harmful pesticide yet again,” Patti Goldman, senior attorney at Earthjustice, says in a statement. “It’s unconscionable that industry continues to fight, subjecting children to learning disabilities, when crops have been successfully grown in the two years since chlorpyrifos has been banned.”

Several manufacturers voluntarily agreed to stop making chlorpyrifos because of the EPA’s 2021 ban. The EPA plans to finalize those cancellations Nov. 6, according to a Federal Register notice. It is unclear whether the EPA will modify the cancellations or whether the companies will seek new approvals in light of the court ruling.

Sales of chlorpyrifos in the US were declining even before the EPA finalized the ban. In early 2020, Corteva Agriscience announced that it would stop producing the chemical due to low demand.

Gharda Chemicals is the only pesticide manufacturer that challenged the chlorpyrifos ban. The company joined forces with about two dozen farm groups, which claimed that loss of chlorpyrifos would result in increased costs and lower crop yields for growers.


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