If you have an ACS member number, please enter it here so we can link this account to your membership. (optional)

ACS values your privacy. By submitting your information, you are gaining access to C&EN and subscribing to our weekly newsletter. We use the information you provide to make your reading experience better, and we will never sell your data to third party members.



Sulfoxaflor poses risks to endangered species, US EPA finds

Agency seeks measures to minimize harm to hundreds of protected species

by Britt E. Erickson
July 21, 2022 | A version of this story appeared in Volume 100, Issue 26


The insecticide sulfoxaflor, which is less toxic than organophosphates and neonicotinoids, is likely to harm about one-third of species listed as endangered or threatened in the US, according to a draft biological evaluation released July 19 by the Environmental Protection Agency. The agency predicts that mitigation measures will protect most of those species, however.

The chemical structure of sulfoxaflor.

The EPA is working with Corteva Agriscience, which makes sulfoxaflor, to determine what additional actions are needed to protect all endangered species. Measures could include requiring buffers, limiting use in certain areas, and reducing pesticide drift, the EPA says.

Sulfoxaflor acts on the same receptor as neonicotinoids, which are under scrutiny for harming bees. But it has a different mode of action. The EPA removed sulfoxaflor from the market in 2015 because of concerns about risks to bees. It allowed a few restricted uses in 2016. But in 2019, under the administration of Donald J. Trump, the EPA removed those restrictions and allowed new uses.

Environmental groups, which sued the EPA over its 2019 decision, are not surprised by the new evaluation. “This disturbing but very predictable finding shoots gaping holes in the myth promoted by the EPA and pesticide industry that new pesticides like sulfoxaflor are safe,” Stephanie Parent, a senior attorney at the Center for Biological Diversity, one of the plaintiffs in the case, says in a statement. A ruling in the case is expected soon.



This article has been sent to the following recipient:

Chemistry matters. Join us to get the news you need.