Skip to main content

A Ban or New Rules for Chlorpyifos May Be Coming Soon

Farmer standing over insecticide jug in wheatgrass field
Courtesy: Canva

Originally Submitted: May 6, 2021

Chlorpyrifos is an insecticide active ingredient that belongs to the organophosphate insecticide class (Group 1B). Organophosphates are acetylcholinesterase inhibitors, which means that they work by disrupting a certain part of the insect nervous system. While all insecticides should be handled with care, organophosphates can pose serious health hazards if exposure occurs, because our nervous system contains the same target sites as insects.

Chlorpyrifos is broken down into a second product in bodies that blocks the natural breakdown of acetylcholine, a neurotransmitter. As acetylcholine accumulates, the nervous system is overstimulated, which ultimately kills the target insect and can have the same effect on humans. Repeated exposure over time (chronic), is how people are harmed by chlorpyrifos.

Check your insecticide labels to see if you are using (or storing) any chlorpyrifos products. The insecticide sections of the latest South Dakota Pest Management Guides contain tables that quickly show what pests can be managed by these products and include a selection of trade names that you might encounter.

In 2020, Corteva Agriscience announced that it would stop producing insecticide products that contained chlorpyrifos. This decision was based on declining sales. Recently, a federal appeals court in California gave the U.S. Environmental Protection Agency (EPA) a 60-day deadline to either ban chlorpyrifos or set new guidelines for its use. We will continue to monitor the EPA’s decision.