Iowa Farmer Sues Over Paraquat Exposure

Legal Challenges Grow Over Paraquat's Alleged Parkinson's Disease Connection

Todd Neeley
By  Todd Neeley , DTN Environmental Editor
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An Iowa farmer is the latest producer to file a class-action lawsuit against Syngenta and Chevron USA on the handling of paraquat-based pesticides. (DTN file photo)

LINCOLN, Neb. (DTN) -- An Iowa farmer is the latest producer to file a class-action lawsuit arguing that Syngenta and Chevron USA failed to notify users of the alleged dangers of using paraquat-based pesticides, including the potential risk of acquiring Parkinson's disease.

The companies face many ongoing legal challenges to the chemical's registration. Syngenta is a major registrant of paraquat herbicides and Chevron has manufactured and sold some paraquat herbicides in the past.

Currently the U.S. Judicial Panel on Multi-District Litigation is considering a motion to move at least 14 similar cases filed in six different federal courts to the U.S. District Court for the Northern District of California, according to court documents.

Paraquat is a Group 22 herbicide sold under brand names like Gramaxone, Firestorm and Parazone, used most commonly on soybeans, cotton, orchards and pasture.

In this most recent class-action lawsuit filed this month in the U.S. District Court for the Southern District of Iowa, Greenfield, Iowa, farmer Doug Holliday is seeking medical monitoring and other relief on behalf of himself and other farmers as a result of repeated exposure to paraquat. Holliday has not been diagnosed with Parkinson's.

"In the 1990s and more recently, Mr. Holliday sprayed paraquat on his ground crops," the lawsuit said.

"Defendants knew that, when used as directed and/or in a reasonably foreseeable manner, consumers (including the plaintiff) would be exposed to paraquat, including through the epithelial tissues, respiratory system, and digestive system, and that this exposure significantly increased the risk that plaintiff and consumers would develop Parkinson's disease.

"Despite this knowledge, defendants did not adequately warn plaintiff or paraquat consumers that their use of and exposure to paraquat significantly increased their risk of developing Parkinson's disease."

In addition, the lawsuit alleges the companies didn't "adequately test" paraquat's potential health effects.

"Instead, defendants sold paraquat with complete disregard and reckless indifference to the safety of plaintiff and members of the nationwide class defined as: 'All persons in the United States who used or were exposed to paraquat and who have not been diagnosed with Parkinson's disease,'" the lawsuit said.

"Because plaintiff and the class members have been exposed to paraquat and are at an increased risk of developing Parkinson's disease, they require diagnostic testing different from that provided in routine medical care to promote early detection and treatment of Parkinson's disease."

Chevron said in a statement to DTN, "Chevron sympathizes with families affected by Parkinson's disease. We do not believe that the former Chevron Chemical Company, which ceased its business over 30 years ago, had any role in causing the plaintiffs' illnesses and we will vigorously defend against the allegations in the lawsuits."

Syngenta did not respond to DTN's request for comment.


While a number of paraquat cases have been filed, future class actions may depend on a case set for oral arguments starting June 1 in St. Claire County, Illinois.

In September 2017, Thomas Hoffmann and his wife Diana Hoffmann filed a lawsuit against Syngenta and Chevron. Thomas Hoffmann is a life-long farmer from Clinton County, Illinois.

In his 268-page lawsuit Hoffmann claimed he was regularly exposed to paraquat for about 30 years while farming. Hoffmann was diagnosed with Parkinson's disease in 1998 and alleges in the lawsuit it was caused by exposure to paraquat. His lawsuit was filed on behalf of himself and seven other farmers and their wives making similar allegations.

"Beginning in the 1970s and continuing through the late 1990s, plaintiff Thomas Hoffmann was repeatedly exposed to paraquat though inhaling, ingesting and absorbing it while it was being mixed or loaded," the Hoffmann lawsuit said, "while it was being or recently had been sprayed, while tanks and equipment used to spray it were being maintained, and while he was in fields where it had been sprayed."

In Syngenta's 2018 financial statement,…, the company said: "Syngenta strongly believes that these complaints are without merit and will vigorously defend the lawsuits."

Paraquat's use has increased steadily in the United States since 2013, with the growth of herbicide resistance in weed populations. Applications rose from less than 5 million pounds a year to as high as 12 million pounds per year in 2017, with most growth concentrated in soybeans, cotton, orchards and pasture.

Paraquat has been the target of lawsuits and controversy in the past, given its high toxicity, its role in poisoning accidents and research suggesting it might be linked to Parkinson's disease.

The herbicide is undergoing EPA's routine 15-year re-registration review and the agency released its draft of human health and ecological risk assessments of paraquat in October 2019.

In October 2020 the EPA released an interim decision on paraquat, "Based on this review, EPA concluded that there is insufficient evidence to link registered paraquat products to any of the health outcomes investigated, including Parkinson's disease, when used according to the label." The agency, however, proposed a number of changes to paraquat use to protect applicators and the environment.

Read more about paraquat here:…

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Todd Neeley

Todd Neeley
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