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New measures proposed to curb chlorpyrifos exposure

EPA plan aims to reduce risks of neurotoxic pesticide to human health and the environment

by Britt E. Erickson
December 8, 2020

The chemical structure of chlorpyrifos

The organophosphate insecticide chlorpyrifos would remain on the US market with additional restrictions, under a proposed interim decision announced Dec. 4 by the US Environmental Protection Agency. The proposed measures include changes to the label that limit how much chlorpyrifos can be sprayed, additional personal protection equipment for workers who spray the pesticide, and steps to reduce spray drift to non-target organisms.

The decision comes as several states, including California, phase out most uses of chlorpyrifos because of its ability to disrupt the developing nervous system. The EPA proposed to ban the use of chlorpyrifos on food in 2016, but reversed that decision in 2017 under the Trump administration.

Chlorpyrifos is registered for use on numerous agricultural crops, including corn, soybeans, alfalfa, oranges, wheat, and tree nuts. Overall its usage has declined over the past decade, but use on sorghum, sweet corn, sunflowers, tobacco and pears has increased, according to the EPA. Manufacturer Corteva announced earlier this year that it would stop making chlorpyrifos by the end of the year, citing reduced demand.

Environmental groups have been urging the EPA to ban chlorpyrifos since 2007. The agency denied a petition to do so in 2017 and again in 2019. The petitioners, represented by environmental advocacy group Earthjustice, are challenging the 2019 decision. Oral arguments were heard in July 2020, and the court has yet to issue a decision in the case.

The EPA’s proposed restrictions do not go far enough, the petitioners say. “EPA is refusing to protect children from damage to their brains and learning disabilities. Even with the new protections, the agency is still failing children, who will continue to be exposed to chlorpyrifos at levels that cause lifelong damage,” Patti Goldman, managing attorney at Earthjustice, says in a statement.

The EPA is accepting public comments until Feb. 5 on its proposed restrictions, as well as its draft human health and ecotoxicology risk assessments for chlorpyrifos. The agency expects to complete the registration review process for several organophosphate pesticides, including chlorpyrifos, in 2022.



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