Chlorpyrifos

Chlorpyrifos (IUPAC name: O, O-diethyl O-3, 5, 6-trichloropyridin-2-yl phosphorothioate) is a crystalline organophosphate insecticide. It was introduced in 1965 by Dow Chemical Company and is known by many trade names (see table), including Dursban and Lorsban. It acts on the nervous system of insects by inhibiting acetylcholinesterase.
Chlorpyrifos is moderately toxic to humans and chronic exposure has been linked to neurological effects, developmental disorders, and autoimmune disorders. Exposure during pregnancy retards the mental development of children, and most use in homes has been banned since 2001 in the U. S. [4] In agriculture, it remains "one of the most widely used organophosphate insecticides", according to the United States Environmental Protection Agency (EPA). [5]