08/11/2026
The California Department of Pesticide Regulation announced Monday that the pesticide paraquat-dichloride is being phased out, as all the pesticide’s manufacturers have voluntarily cancelled their product registrations in the state.
Exposure to the pesticide, which is more commonly referred to simply as paraquat, has been tied to potential thyroid issues and birth defects in humans, according to reports from the state pesticide regulation agency. The research also notes potential negative effects on other species such as birds.
The pesticide is one of the nation’s most widely used herbicides, according to the U.S. Environmental Protection Agency. Commonly used to kill weeds, the product can only be used by professionally licensed applicators, according to the state agency. There are “no homeowner uses and no products registered for application in residential areas,” according to the EPA.
The rollback of paraquat is the first significant pesticide eradication effort in California since around 2019. That year, the state announced the end of chlorpyrifos, a chemical linked to brain disorders.
The California Department of Pesticide Regulation has released a report showing links between paraquat pesticide exposure and birth defects.
