Experts concerned Paraquat remains legal in the U.S. despite international bans and proven health risks

A widely used herbicide, banned in over 70 countries due to its harmful effects on human health and wildlife, continues to be legally sprayed in U.S. fields. Despite being labeled unsafe by domestic officials, Paraquat was reapproved for use by the Environmental Protection Agency (EPA) in 2024, sparking a significant legal challenge.

Nonprofit Earthjustice, along with various farming and environmental groups, has filed a lawsuit to revoke the EPA’s endorsement of Paraquat. This legal action comes in response to the agency’s decision which now faces mandatory review under California state law.

The California Department of Pesticide Regulation initiated a preliminary investigation which found that the currently registered uses of paraquat in California may adversely affect non-target organisms, including birds, mammals, and aquatic organisms, with the most significant risks to birds.

The Department’s review of existing human health studies does not indicate a causal association between paraquat exposure and Parkinson’s disease. The human health preliminary report identifies a potential association between exposure to paraquat, thyroid impacts and birth defects. The department is investigating these potential human health associations that may be linked to current paraquat uses and may require additional studies. The investigation also found that the herbicide poses a threat to several endangered species, such as the San Joaquin kit fox and Swainson’s hawk.

Jonathan Evans, Environmental Health Legal Director at the Center for Biological Diversity, emphasized the growing evidence against Paraquat. “The evidence continues to mount that Paraquat is just too dangerous,” he stated, reflecting a broader consensus on the immediate need for a ban.

However, a complete evaluation by the Department of Pesticide Regulation is not scheduled for completion until January 2029, raising concerns about the prolonged exposure risks.

The broader issue at stake is the critical role of pesticides in affecting biodiversity and human health. Pesticides have been linked to reproductive issues, cancer, and developmental delays in children. They are also detrimental to animal populations, contributing to the decline of various species, including vital pollinators like bees, which are crucial for global food production.