Full Breakdown
California Moves to Phase Out Paraquat, the Toxic Herbicide
8/13/2026, 10:35:03 PM
State Decision and Implementation
The California Department of Pesticide Regulation (DPR) cancelled the state’s final paraquat registrations, beginning a two-year phase-out. The last voluntary cancellation was filed on August 6. Licensed dealers may sell existing inventories for up to two years after cancellation. The move follows a “voluntary” industry decision after the 2024 law required DPR to re-evaluate paraquat’s risks.
Legislative Background
In 2024, Assemblymember Laura Friedman (D-Glendale) authored AB 1963, mandating DPR to reassess paraquat’s health and environmental impact. Registrants were required to submit additional scientific data by June 5 2026. Rather than provide the data, manufacturers began withdrawing registrations in April 2026, culminating in the August 6 cancellation.
Usage and Health Concerns
California accounts for the nation’s largest paraquat consumption, with roughly 14 million pounds sprayed annually on almonds, grapes, cotton, soybeans, pistachios and other crops, especially in the Central Valley. Exposure pathways—skin contact and inhalation—are linked to acute toxicity, cancer, organ failure and lung scarring. Studies in Central California farming communities have shown elevated rates of Parkinson’s disease, thyroid disorders and birth defects among those exposed. Wildlife risks include threats to the San Joaquin kit fox and Swainson’s hawk.
Timeline
- 2024 – AB 1963 enacted, directing DPR to re-evaluate paraquat.
- April 2026 – Manufacturers begin voluntary registration cancellations.
- June 5 2026 – Deadline for registrants to submit additional health data (missed).
- March 17 2026 – Paraquat spill in Dorris, Siskiyou County triggers shelter-in-place orders for ~600 residents.
- August 6 2026 – DPR confirms the final voluntary cancellation.
Official Statements & Responses
California Secretary for Environmental Protection Yana Garcia said the state will continue moving toward pest-management practices that protect health and ecosystems. DPR Director Karen Morrison emphasized the need for robust data to identify human and environmental risks. The agency noted that paraquat remains in soil for decades, complicating exposure mitigation.
Criticism & Opposition
The California Farm Bureau opposed the phase-out, arguing that paraquat is an essential tool for growers and that the 2024 law “bypasses the scientific review process.” Spokesperson Isabella Quinonez warned that the loss could increase production costs and reduce access to effective weed control.
On-the-Ground Reports
The March 17 spill involved a 140-gallon tank that released roughly 50 gallons of concentrated paraquat onto Highway 97 in Dorris. Emergency responders ordered a shelter-in-place, closed the highway and instructed residents to wash vehicles without touching tires. No injuries were reported; officials called the incident a “close call” that underscored the chemical’s acute danger.
Conflicting Reports & Gaps
Scientific consensus on paraquat’s link to Parkinson’s disease remains unsettled. Some studies demonstrate neurotoxic mechanisms that could trigger Parkinson’s, while other research finds no clear association. The U.S. EPA has not confirmed a causal link but has expressed concern about volatilization and non-occupational inhalation exposure. A federal lawsuit filed by public-health groups alleges EPA inaction despite “broad scientific consensus,” yet the agency maintains that further evidence is needed.
Verbatim Quotes
- “Paraquat is the most acutely lethal pesticide ever made,” — Nathan Donley, Center for Biological Diversity
- “California is sending a powerful message that there is no place for paraquat in modern agriculture,” — Bernadette Del Chiaro, Environmental Working Group
What’s Next
The EPA plans a summer roundtable to hear from scientists, farmworkers and advocates about paraquat’s safety challenges. In June, Representatives Anna Paulina Luna (R-FL) and Chellie Pingree (D-ME) introduced the bipartisan Paraquat Prevention Act, signaling potential federal legislative action. California’s phase-out will continue to shape pesticide regulation discussions nationwide.
