November 08, 2010
Image of Chlorpyrifos 3D Image of Chlorpyrifos

Chlorpyrifos is a thiophosphate insecticide and acaricide sold under such names as Lorsban and Dursban. Dow Chemical first marketed it in 1965 as a household pesticide. Because chlorpyrifos is associated with several health problems, in 2001 FDA severely restricted its use , but it is still widely used in some countries. More recently, researchers found that it affects several regions of the brain.

MOTW update: August 20, 2018

Chlorpyrifos was once a widely used insecticide, but since 2001 its use has been increasingly restricted. In the latest development, the US 9th Circuit Court of Appeals chastised the US Environmental Protection Agency for its failure to act on findings of chlorpyrifos’ harm to children’s brains and ordered the Trump administration to ban the pesticide within 60 days.

MOTW update: 
May 20, 2019

Chlorpyrifos is an insecticide first marketed in 1965 that for the past 20 years has been increasingly restricted in the United States and European Union. Last week, the California Environmental Protection Agency announced that all uses of chlorpyrifos will be banned in the state. This action follows similar ones taken by Hawaii and New York.

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