Chlorpyrifos

Chlorpyrifos is an organophosphate insecticide tied by a large body of research to neurodevelopmental harm in children, including lower birth weight, reduced IQ, working-memory loss, attention disorders, and delayed motor development from prenatal exposure. The EPA revoked all food-use tolerances in August 2021, effectively banning it on food and animal feed nationwide — but the Eighth Circuit Court of Appeals vacated that rule in November 2023 and reinstated the tolerances after industry challenges. The EPA proposed a narrower rule in December 2024 that would again ban most food uses, carving out exceptions for only 11 crops (alfalfa, apple, asparagus, tart cherry, citrus, cotton, peach, soybean, strawberry, sugar beets, and wheat) in specific states, with an amended risk assessment and interim decision expected in 2026 — a regulatory back-and-forth spanning more than a decade.