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Chemical Regulation

Court orders EPA to ban chlorpyrifos

9th Circuit Court of Appeals directs agency to finalize Obama-era proposal

by Britt E. Erickson
August 10, 2018


Chemical structure of chlorpyrifos.

In a win for environmentalists and farmworkers, the U.S. Court of Appeals for the Ninth Circuit has ordered the Environmental Protection Agency to finalize a proposed ban on the organophosphate insecticide chlorpyrifos. The Aug. 9 ruling gives EPA 60 days to revoke all allowable limits in food and cancel all approved uses for the pesticide, which is linked to neurodevelopmental disorders in children.

EPA determined in a 2015 human health risk assessment that combined exposure to chlorpyrifos from food and drinking water in the U.S. likely exceeds safe levels, particularly for children. The agency twice proposed to ban chlorpyrifos under the Obama administration, but the agency did not finalize either rule. In March 2017, then-EPA Administrator Scott Pruitt delayed EPA’s proposed ban and put off any decision about chlorpyrifos until 2022.

“Over nearly two decades, EPA has documented the likely adverse effects of foods containing the residue of the pesticide chlorpyrifos on the physical and mental development of American infants and children, often lasting into adulthood,” District Judge Jed S. Rakoff wrote in an opinion accompanying the ruling. “Yet, over the past decade and more, the EPA has stalled on banning chlorpyrifos.”

The case dates back to a 2007 petition from environmental groups, urging EPA to ban chlorpyrifos on food crops. EPA failed to respond to the petition until November 2015, when it was directed to do so by a court order. At that time, EPA proposed to revoke all food tolerances for chlorpyrifos.

Chlorpyrifos has been used as a pesticide in the U.S. since 1965. Manufacturers voluntarily canceled residential uses of the insecticide in 2000 because of health risks identified by EPA. Chlorpyrifos acts by inhibiting acetylcholinesterase, an enzyme essential for neurotransmitter function. The chemical is used on dozens of food crops, including fruits, vegetables, and nuts.

After pushing EPA for decades to ban chlorpyrifos, environmentalists are elated. “The court has made it clear that children’s health must come before powerful polluters,” Erik Olson, senior director of health and food at the Natural Resources Defense Council (NRDC), said in a statement. NRDC is one of the environmental groups that filed the 2007 petition. “This is a victory for parents everywhere who want to feed their kids fruits and veggies without fear it’s harming their brains or poisoning communities.”

Sen. Tom Udall (D-NM), who has been leading an effort in Congress to ban chlorpyrifos, is urging EPA Acting Administrator Andrew Wheeler “to take immediate action to show that the Trump EPA will stop prioritizing the profits of industry and start putting public health first.” Udall introduced legislation in 2017 to ban chlorpyrifos. “It is long past time for this dangerous chemical to come off our food, off the shelves, and off the market,” Udall said in a statement in response to the court ruling.

DowDuPont’s agriculture division, which manufactures chlorpyrifos, claims that the insecticide is a “critical pest management tool used by growers around the world to manage a large number of pests.” The appeals court ruling “was a split decision of the panel and we agree with the dissenting judge’s opinion. We expect that all appellate options to challenge the majority’s decision will be considered. We will continue to support the growers who need this important product,” the company said in a statement.

UPDATE: This story was revised on Aug. 10, 2018, to add comments from DowDuPont’s agriculture division.


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