Across California
Health & Fitness

Pesticide Associated With Birth Defects To Be Phased Out In CA

The chemical is banned in dozens of countries, as well as Vermont.

A pesticide that may be tied to birth defects and thyroid issues is being phased out in California, state regulators announced this week.

Makers of pesticide products containing paraquat-dichloride voluntarily canceled their product registrations after the California Department of Pesticide Regulation demanded the manufacturers submit scientific data to address newly found gaps in the agency's human health toxicology database, according to the department.

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"For years, communities have fought to end the use of paraquat, a weedkiller associated with negative impacts to human health and wildlife," California Secretary for Environmental Protection Yana Garcia said in a news release. "California will keep moving toward pest management practices that protect health and our ecosystems."

The last cancellation happened on Thursday.

The department reevaluated paraquat in 2024 in accordance with state law and released two preliminary assessments, which identified a potential association between exposure to the pesticide and thyroid impacts and birth defects, according to the agency. Findings also showed paraquat may adversely affect other organisms, most significantly birds, the department reported.

California Farm Bureau spokesperson Isabella Quinonez told the Los Angeles Times that paraquat was "an important tool for California farmers" and said the phaseout "raises a broader concern about California's increasingly difficult marketplace."

More Possible Health Risks

A 2023 Times report documented thousands of lawsuits against manufacturer Syngenta alleging paraquat gave workers Parkinson's disease, a possible link that has yielded conflicting results in studies and that the company rejected, according to the newspaper.

California is the largest paraquat user in the U.S., with use heavily concentrated in the San Joaquin Valley, according to the Center for Biological Diversity, which noted in a news release that a 2024 California law required the state to continue reevaluating the pesticide's use.

"The fact is, farmworkers and nearby communities have been unprotected from the health threats of paraquat making this decision long overdue," Bernadette Del Chiaro, senior vice president for California with the Environmental Working Group, said in a news release.

The group noted that the move to stop using paraquat in California comes after a large container of the pesticide in March fell off a truck in Dorris, spilling about 60 gallons of the chemical and causing officials to lock down 600 residents, including a local elementary school.

Paraquat is banned in dozens of countries, as well as Vermont, which became the first state to prohibit its use earlier this year, according to the Environmental Working Group.

Under California law, licensed dealers can possess and sell paraquat for up to two years following the date of the product's cancellation, the state department said.

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