SACRAMENTO – The California Department of Pesticide Regulation (DPR) announced today that all manufacturers of pesticide products containing the active ingredient paraquat-dichloride (paraquat) have voluntarily cancelled their product registrations, beginning the phase-out of the use of paraquat in California.
“For years, communities have fought to end the use of paraquat, a weedkiller associated with negative impacts to human health and wildlife,” said California Secretary for Environmental Protection Yana Garcia. “California will keep moving toward pest management practices that protect health and our ecosystems.”
DPR initiated the reevaluation of paraquat in November 2024, aligning with requirements in Food & Agricultural Code (FAC) section 14086, and released two preliminary scientific assessments the following month. DPR’s preliminary reports identified a potential association between paraquat exposure and thyroid impacts and birth defects. The reports also indicated paraquat may adversely affect other organisms, with the most significant risks to birds.
“We need the right data to identify where there are risks to people and the environment,” said DPR Director Karen Morrison. “This is a cornerstone of our continuous evaluation process to respond to evolving science on the impacts of pesticides.”
Reevaluation gives DPR the authority to require registrants – the companies that make pesticides – to develop and submit new scientific studies needed to fully understand emerging risks that were unknown at the time of registration. For paraquat, DPR invoked this reevaluation authority to require registrants to submit scientific data by June 5, 2026, to address newly identified gaps in DPR’s human health toxicology database, among other requirements. In lieu of providing required data, companies began voluntarily cancelling registration of paraquat pesticide products in California in April, with the last registrant voluntarily cancelling its registration on August 6, 2026.
