October 05, 2015

Sulfoxaflor is a pesticide that kills insects by attacking their central nervous system. It is a member of the sulfoximine family of insecticides. In 2013, the US Environmental Protection Agency (EPA) approved this Dow AgroSciences product for use in the United States. It is also registered in some Central American and east Asian countries.

The EPA registered sulfoxaflor despite its potential toxicity to honeybees. It recommended that the insecticide not be used when flowering crops are attracting bees.

A consortium of beekeeping trade groups sued the EPA shortly after registration, believing that sulfoxaflor would exacerbate the declining bee population. In September 2015, a federal appeals court overturned the registration by ruling that the supporting studies were insufficient to demonstrate that sulfoxaflor does not cause environmental harm. Dow says it will perform additional studies and may appeal the court’s decision.

MOTW Update

The October 5, 2015, MOTW noted that a federal appeals court had overturned the registration of the insecticide sulfoxaflor because of its toxicity to honeybees. As a result of this court order, on November 12, 2015, the US Environmental Protection Agency stopped the sale of this chemical in the United States. The manufacturer, Dow AgroSciences, intends to work with EPA to return sulfoxaflor to the market.

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