Paraquat Parkinson’s Disease Risk Made Herbicide Unreasonably Dangerous, Lawsuit Alleges

According to allegations raised in a recently filed product liability lawsuit, the Parkinson’s disease risk linked to Paraquat exposure makes the widely used weed killer unreasonably dangerous to users and the public.

Scott Marsh filed the complaint (PDF) in the U.S. District Court for the Southern District of Illinois on July 30, naming Syngenta Crop Protection and Chevron, U.S.A., Inc. as the defendants, indicating that inadequate warnings and directions for the use of Paraquat have been provided for decades.

Paraquat is a herbicide that has been widely used throughout the United States since the mid-1960s, which is used to control weeds and long grass. Since accidentally ingesting even a small amount poses a serious risk of Paraquat poisoning and death, the products are heavily restricted in the United States, requiring users to go through a training certification process. However, Marsh claims Syngenta and Chevron have withheld information about the Paraquat Parkinson’s disease risk, which users face even when the recommended precautions are followed.

According to Marsh’s lawsuit, he was regularly exposed to Paraquat from 1984 to 2000 at different sites across northern Illinois while working for a lawncare and maintenance company. He was a licensed Paraquat applicator, and part of his job included mixing Paraquat as well as filling tanks with the herbicide and applying it while servicing Commonwealth Edison stations across the state.

In 2015, Marsh was diagnosed with Parkinson’s disease, which is a progressive neurodegenerative disorder of the brain that affects the part of the central nervous system that controls movement. However, the lawsuit indicates he was never given any warning Paraquat caused Parkinson’s disease until earlier this year.

“The paraquat that Defendants… designed, manufactured, distributed, and sold, and to which Plaintiff was exposed, was in a defective condition that made it unreasonably dangerous, in that when used in the intended and directed manner or a reasonably foreseeable manner… it was likely to cause or contribute to cause latent neurological damage that was both permanent and cumulative,” according to the complaint.

Marsh indicates Syngenta and Chevron concealed, suppressed and omitted information about the risks associated with inhaling, ingesting or absorbing the herbicide into the body while using it, standing nearby while it was being used or entering fields where it had been sprayed.

While genetics are often believed to be a major cause of Parkinson’s disease, growing research indicates genes are only believed to be associated with about one-in-ten cases. Exposure to herbicides and pesticides are increasingly considered a leading risk, especially when combined with other factors that place individuals at risk of the development of Parkinson’s.

The case joins dozens of Paraquat Parkinson’s disease lawsuits now filed in courts throughout the U.S., each raising similar allegations.

Following an order issued by the U.S. Judicial Panel on Multidistrict Litigation in June, the complaints are being transferred to the U.S. District Court for the Southern District of Illinois, where the Paraquat litigation has been centralized before one judge for coordinated discovery and pretrial proceedings. However, if Paraquat settlements or another resolution for the litigation is not reached, each individual case may later be returned to the home district where it was originally filed for a future trial.

Written by: Irvin Jackson

Senior Legal Journalist & Contributing Editor

Irvin Jackson is a senior investigative reporter at AboutLawsuits.com with more than 30 years of experience covering mass tort litigation, environmental policy, and consumer safety. He previously served as Associate Editor at Inside the EPA and contributes original reporting on product liability lawsuits, regulatory failures, and nationwide litigation trends.




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