EPA backing of pesticide poses human health risks, groups allege

The Environmental Protection Agency (EPA) is risking the health of farmworkers and other Americans by allowing continued widespread use of a highly toxic pesticide called paraquat that has been linked to Parkinson’s disease and other health problems, a coalition of advocacy groups alleged in court filings this week.

The group of eight organizations is challenging a 2021 EPA decision that the group’s allege violates federal law. They say the EPA failed to adequately account for the “magnitude” of the risks posed by paraquat use, and improperly determined that the benefits of paraquat for crop production outweigh the dangers to farmworkers and others.

“EPA’s flawed risk assessment and one-sided weighing of paraquat’s risks and benefits will leave people more likely to develop Parkinson’s disease and suffer other serious harms, merely because of the jobs they hold or the places they live,” the group stated in an opening brief filed Wednesday with the 9^th U.S. Circuit Court of Appeals. “EPA repeatedly understated the extent of paraquat’s adverse effects, and it failed to lawfully address the serious risks it did identify.”

The group is asking the court to overturn the EPA decision on paraquat and order the agency to conduct analyses required under the Federal Insecticide, Fungicide, and Rodenticide Act (FIFRA).

The petitioners in the case are the California Rural Legal Assistance Foundation; the Michael J. Fox Foundation for Parkinson’s Research; Farmworker Association of Florida, Inc.; Farmworker Justice; Pesticide Action Network North America; Alianza Nacional de Campesinas; Center for Biological Diversity; and Toxic Free North Carolina.

The EPA has until July 25 to file its response. Syngenta AG, the key maker of paraquat, has intervened in the action, and has until August 14 to file its response.

In the EPA’s interim decision on paraquat, announced last July, the agency said it had found more than 70 scientific articles covering a range of health impacts of paraquat, including many dealing with the potential association between paraquat and Parkinson’s. The EPA found that there was “limited, but insufficient, epidemiologic evidence” to conclude that there is a clear association between the disease and exposure to the pesticide. 

The agency said in that decision that it would continue to allow paraquat to be sprayed onto farmland from the air, but would put in place some new restrictions to protect people from being exposed through wind drift.

“The agency has taken proactive steps to ensure paraquat is used in a manner that will not cause unreasonable adverse effects to human health or the environment…” the EPA states on its website.

Widely used

Paraquat has been used in the United States since 1964 as a tool to kill broadleaf weeds and grasses. Farmers often use paraquat before planting crops or before those crops emerge. Though paraquat has been banned in several countries, it is one of the most widely used herbicides in the United States, with an average of 8.5 million pounds applied annually to 15.8 million acres, according to the EPA.

Paraquat is used in growing soybeans, cotton, and corn as well as in growing grapes, pistachios, peanuts and many other crops.

Farmers in southern states rely heavily on paraquat, according to the agency, in part because the more popular glyphosate herbicides have lost efficacy as weeds have developed resistance to glyphosate.

The chemical has long been known to be extremely dangerous to anyone who ingests even a small amount, and regulators have issued warnings and placed restrictions on its use because of poisoning risks.

But whether or not it causes Parkinson’s disease is a matter of fierce debate. Syngenta maintains that there is no credible evidence of a connection between the disease and the weed killer.

Still, several scientific studies have linked paraquat to Parkinson’s, including a large study of U.S. farmers jointly overseen by multiple U.S. government agencies. The Agricultural Health Study (AHS) said it found that “exposure to agricultural pesticides may increase a person’s risk of developing Parkinson’s disease.” In 2011, AHS researchers reported that “participants who used paraquat or rotenone were twice as likely to develop Parkinson’s disease as people who didn’t use these chemicals.”

More than 1,000 people are currently suing Syngenta in courts around the country, alleging they or their loved ones developed Parkinson’s because of paraquat exposure. A first trial in the litigation is set for February of next year. Syngenta settled with plaintiffs in a trial that had been scheduled for last summer. 

In the opening brief filed Wednesday, the petitioners said the EPA improperly dismissed the risks of Parkinson’s disease from paraquat exposure by “mischaracterizing” data from animal research studies. The groups said the EPA risk assessment also ignores the multiple ways people are exposed to paraquat. And they allege, the EPA emphasized the economic “savings” for growers in a “one-sided assessment” that did not properly balance against human health risks in addition to Parkinson’s as well as risks to mammals, birds, bees and other wildlife.

”EPA’s finding that paraquat’s benefits outweigh its human health and environmental risks is unsupported by substantial evidence,” the brief states.