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California to ban chlorpyrifos sooner than expected

by Britt E. Erickson
October 12, 2019 | A version of this story appeared in Volume 97, Issue 40


Close up of oranges on a tree in California.
Credit: Shutterstock
California orange growers will need to find an alternative to the insecticide chlorpyrifos by the end of next year.
Structure of chlorpyrifos.

California regulators have struck a deal with pesticide manufacturers to phase out the sale of chlorpyrifos by Feb. 6, 2020, and nearly all uses of the organophosphate insecticide by the end of 2020. Earlier this year, the California Department of Pesticide Regulation (DPR) started the process of canceling all uses of the pesticide in the state. But the process could have taken up to 2 years if companies pursued administrative hearings or appealed the decision. “This agreement avoids a protracted legal process while providing a clear timeline for California farmers as we look toward developing alternative pest management practices,” Jared Blumenfeld, the state’s secretary for environmental protection, says in an Oct. 9 statement. Chlorpyrifos is associated with neurodevelopmental problems and impaired brain function in children, and is likely to be removed from the European Union market by January 31. The chemical is sprayed on numerous crops grown in California, including almonds, citrus, and grapes, but its use has been steadily declining over the past decade, according to the DPR. A few products that contain granular forms of chlorpyrifos, which represent less than 1% of the pesticide’s agricultural use in California, can remain on the market.


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