Paraquat Toxicity Resulted in Parkinson’s Disease Diagnosis, Lawsuit Alleges

The grass and weedkiller paraquat is known to be extremely toxic and poses a serious risk of poisoning if ingested. However, according to allegations in a recently filed lawsuit, an Illinois woman indicates that after years of what she believed was safe exposure while mixing, loading and spraying the herbicide on farms, paraquat caused Parkinson’s disease.

Barbara Piper filed the complaint (PDF) in the U.S. District Court for the Southern District of Illinois on February 26, presenting claims against Syngenta Crop Protection, LLC and Chevron U.S.A., Inc. as defendants.

Given the known toxicity of paraquat, it is subject to serious restrictions in the United States. However, warnings and safety instructions largely focus on the risk of paraquat poisoning from accidentally ingesting the herbicide, even though a number of studies published in recent years indicate that normal handling of paraquat may cause Parkinson’s disease, which is a severe and progressive nervous system disorder that causes debilitating tremors and movement problems.

Piper, born in 1954, worked on her parents’ farm in Franklin County from 1975 to 2017. She also worked on her own farm in Jefferson County from 1980 to 2017. During her work on both farms, she was regularly in or near fields where paraquat products had been sprayed, and regularly mixed, loaded, sprayed and cleaned up paraquat products.

Following decades of exposure, Piper was diagnosed with Parkinson’s disease in 2019, and the lawsuit indicates that Sygenta and Chevron knew or should have known about the risk associated with their products, yet provided false and misleading information about paraquat’s toxicity for decades.

“Many epidemiological studies (studies of the patterns and causes of disease in defined populations) have found an association between paraquat exposure and Parkinson’s disease, including multiple studies finding a two‐ to five‐fold or greater increase in the risk of Parkinson’s disease in populations with occupational exposure to paraquat compared to populations without such exposure,” Piper’s lawsuit states.

Paraquat is used to kill broadleaf weeds and grasses before planting numerous types of crops, is also used to control weeds in orchards, and is sometimes sprayed on plants before harvest in order to dry them out. However, research over the years has repeatedly warned that the toxic effects of Paraquat go beyond weeds and also impact animals and humans.

A number of studies published over the past decade have established a link between paraquat and Parkinson’s, finding that farmers using the herbicide may be several times more likely to develop the disorder. Research has also found that individuals with certain genetic variations may be 11 times more likely to develop Parkinson’s after paraquat exposure.

Parkinson’s disease affects more than 500,000 Americans, with approximately 50,000 new cases each year. The disease causes the loss of motor functions, causing imbalance and shaking, which gets progressively worse over time.

The claim joins a growing number of paraquat Parkinson’s lawsuits now being filed by former individuals exposed to the herbicide in prior decades, alleging the manufacturers failed to provide adequate warnings and safety instructions for consumers.