SACRAMENTO, Calif. – Today the California State Assembly voted to ban the highly toxic pesticide paraquat, which is linked to Parkinson’s disease. If the Senate passes the bill and Gov. Gavin Newsom signs it into law, the state would become the first to ban the herbicide’s use.
Assembly Bill 1963, authored by Assemblymember Laura Friedman (D-Burbank) and sponsored by the Environmental Working Group, would prohibit the use of paraquat on California fields and orchards starting January 1, 2026. To become law, the bill must make its way through Senate committees, pass a Senate vote this summer and then be signed by Newsom by September.
“Seasonal agricultural workers brave some of the worst environmental working conditions in the state. Agricultural field workers are also composed nearly entirely of undocumented or first-generation Latino immigrants that work for low wages in fields saturated by paraquat, mostly without access to quality health care. That lack of health care should not be compounded by work-issued Parkinson’s disease,” Friedman said. “We don’t have a cure for Parkinson’s, but A.B. 1963 will lessen the incidence rate for agricultural workers and communities surrounding the fields where paraquat is sprayed.”
Peer-reviewed science shows that paraquat exposure is associated with a higher risk of developing Parkinson’s disease, a progressive brain disorder characterized by involuntary movements like tremors, stiffness and impaired balance. Over time, these symptoms worsen, leading to permanent and often profound impairment of movement and speech.
“Assemblymember Friedman has shepherded this bill through the Assembly in order to protect farmworkers and nearby residents from a highly toxic pesticide that has been around too long,” said Bill Allayaud, EWG vice president of government affairs in California. “As proven by other countries where paraquat has been banned, the output of California’s farmers will not suffer.”
With A.B. 1963, California would follow in the footsteps of more than 60 countries that have already banned the chemical. Yet in the U.S., the Environmental Protection Agency continues to permit the use of paraquat on crop fields, despite mounting evidence of the danger it poses to people.
An EWG analysis released in March showed that paraquat is disproportionately sprayed in areas of California primarily inhabited by Latino farmworkers and their families, exacerbating environmental health risks for these communities.
“Farmworkers, their families, and nearby communities in California face serious risks from toxic pesticides like paraquat,” said renowned labor leader and civil rights activist Dolores Huerta at an April press conference about A.B. 1963 hosted by Friedman and EWG.
A study using data from the National Institutes of Health found that workers who sprayed paraquat were more than twice as likely to develop Parkinson’s disease than those who applied other pesticides. And a meta-analysis of 13 studies found a 64 percent increase in the likelihood of developing Parkinson’s disease from paraquat exposure.
Most recently, findings from researchers at UCLA show paraquat sprayed within 500 meters, or about 1,640 feet, of where someone lives and works could more than double a person’s odds of developing Parkinson’s.
In April, EWG Senior Toxicologist Alexis Temkin, Ph.D. testified before the Assembly’s Committee on Environmental Safety & Toxic Materials about the robust body of scientific research on the herbicide’s serious health harms. She explained that paraquat “has both acute and chronic toxicity, meaning it can harm people both when they’re exposed one time to a single dose, or over time to lower doses.”
Investigative reporting by the nonprofit investigative news outlet The New Lede uncovered that Syngenta, the primary manufacturer of paraquat, chose to hide evidence for decades from the public and the EPA about how paraquat can accumulate in people’s brains.
A.B. 1963 allows for a safety reevaluation of paraquat, with the potential for future use in agriculture, pending completion of the review process. Until then, the ban on paraquat would remain in effect.
###
The Environmental Working Group is a nonprofit, non-partisan organization that empowers people to live healthier lives in a healthier environment. Through research, advocacy and unique education tools, EWG drives consumer choice and civic action.
Full disclosure: The New Lede is a journalism enterprise of EWG but operates independently of the organization’s advocacy and communications departments. EWG has no influence on its editorial decision making.
