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California court orders end to sulfoxaflor use

State violated environmental law when approving pesticide harmful to bees

by Britt E. Erickson
December 9, 2021


The pesticide sulfoxaflor can no longer be used on crops in California, a state superior court ruled Dec. 3. The decision is a win for beekeepers and environmental groups, which challenged California’s approval of agricultural uses for sulfoxaflor in 2020. The groups claimed that the state’s Department of Pesticide Regulation (DPR) violated the law by failing to consider adverse impacts of the chemical on bees.

chemical structure of sulfoxaflor

The court agreed with the petitioners, represented by the environmental law group Earthjustice, that the DPR violated state environmental law when it approved sulfoxaflor pesticides produced by Dow AgroSciences, now Corteva Agriscience.

Sulfoxaflor targets the same nicotinic acetylcholine receptor in insects as neonicotinoid pesticides, which have been under scrutiny for their ability to harm bees. Both sulfoxaflor and neonicotinoids are systemic insecticides, meaning they are taken up by plants and distributed throughout plant tissues. Both are harmful to bees at low doses. But sulfoxaflor has a different mode of action than neonicotinoids and belongs to a class of insecticides called sulfoximines.

“Honeybees and other pollinators are incredibly important in our food systems and our wider ecosystem, but they’re dying in droves because of pesticides like sulfoxaflor,” Earthjustice attorney Greg Loarie says in a statement. “With this ruling, the bees in California are getting much-needed relief just as we’re seeing some of the worst signs of colony collapse,” he says. From April 2020 to April 2021, US beekeepers lost nearly 46% of managed honeybee colonies, according to Earthjustice. The petitioners are now urging California regulators to also protect pollinators from neonicotinoids.

In a separate lawsuit, the groups are challenging the US Environmental Protection Agency’s 2019 decision to allow new uses of sulfoxaflor. The EPA removed the pesticide from the market in 2015 because of a court order to do so to protect bees. Under pressure from growers and Dow, the agency then allowed limited use of the chemical on a few crops with restrictions in 2016. In 2019 under former President Donald Trump’s administration, it removed those restrictions and allowed new uses. A decision in the federal case is expected soon.



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