California begins phaseout of paraquat weedkiller

California is beginning a phaseout of paraquat, a potent weedkiller linked to thyroid issues, birth defects, and risks to wildlife. The California Department of Pesticide Regulation announced that all manufacturers of products containing the active ingredient have voluntarily agreed to withdraw from the market.

While paraquat is banned in over 60 countries, it has remained legal in the United States, with California being a major user. Millions of pounds are sprayed annually on crops such as almonds, grapes, and cotton, particularly in the San Joaquin Valley. The phaseout follows a regulatory reevaluation prompted by state legislation.

Major manufacturers, including the Swiss-based and Chinese-owned Syngenta, have begun canceling their registrations in the state. This move marks California’s first significant pesticide phaseout since the 2019 decision to end the use of chlorpyrifos.