LINCOLN, Neb. (DTN) -- A California man has sued Corteva Agriscience LLC, the Dow Chemical Company and three commercial nurseries, alleging that years of exposure to the insecticide chlorpyrifos drifting from nearby nurseries caused him to develop early-onset Parkinson's disease.

The lawsuit filed in the Superior Court for the State of California, County of Los Angeles, seeks to hold the pesticide manufacturers and commercial applicators responsible under California law for injuries allegedly resulting from long-term, off-target chlorpyrifos exposure. The lawsuit seeks compensatory and punitive damages on behalf of plaintiff Michael Sargent.

DTN reached out to Corteva and Dow seeking comment.

What's noticeably absent is a legal challenge to a label approved by the U.S. Environmental Protection Agency, with a focus instead on product design and testing, safety communications outside of labels, and how the pesticide allegedly was applied near a residential property.

Sargent's lawsuit alleges his exposure to chlorpyrifos started around 2003 and continued into 2022.

He alleges the pesticide reached him through spray drift, airborne inhalation, contaminated soil, plants, surfaces, clothing and equipment via dermal contact and possible ingestion of droplets, according to the lawsuit.

"Plaintiff has no known family history of Parkinson's disease and no known genetic or familial risk factors for the disease," the lawsuit said. "Plaintiff's neurological symptoms began during the period of his exposure to chlorpyrifos."

From 2003 to 2013, Sargent alleges he lived about 20 feet from a nursery with no barriers separating the operation from his residence. From 2017 to 2022, the lawsuit said, Sargent's backyard bordered a nursery separated by a residential fence. The 30-acre nursery operated about a half mile from his residence, according to the complaint.

The Los Angeles County nurseries named in the lawsuit include Abeja Nursery, Azul and Verde Nursery and ABC Nursery Inc. DTN reached out to the nurseries seeking comment.

REPEATED EXPOSURE LINKED

The lawsuit alleges repeated exposure to chlorpyrifos can cause or contribute to permanent neurological injury, including Parkinson's.

Sargent's case targets specific application failures on the part of the nurseries, arguing they breached their duty by "Applying, or causing to be applied, chlorpyrifos in open-air conditions in immediate physical proximity to occupied residences, including plaintiff's, without adequate measures to prevent off-target drift, volatilization, or runoff."

The complaint further alleges the nurseries failed to "employ reasonably available application methods, buffer zones, timing precautions, or engineering controls that would have reduced or eliminated the foreseeable exposure of neighboring residents."

In addition, the lawsuit argues the nurseries failed to warn or notify residents of the timing and nature of chlorpyrifos applications.

"The nursery defendants failed to adequately account for wind speed and direction, control pesticide spray drift and droplet size, use appropriate application methods and maintain adequate setbacks from neighboring residential properties," according to the complaint.

"Despite decades of chlorpyrifos manufacture, distribution, and sale, and scientific evidence concerning its neurological effects, plaintiff alleges that defendants failed to adequately investigate the potential relationship between chronic chlorpyrifos exposure and Parkinson's disease."

The lawsuit alleges the company engaged in misleading safety communications and points to a New York Attorney General investigation of Dow's advertising in the early 1990s, including claims of "No significant adverse health effects will likely result from exposures to Dursban even at levels substantially above those expected to occur when applied at label rates."

The complaint said Dow entered into an agreement in 1994 to stop making alleged false safety claims.

CALIFORNIA LAW

The complaint alleges negligent failure to warn, negligent design, strict-liability design defect, general negligence and trespass, under California law.

Sargent's lawsuit shies away from making claims under the Federal Insecticide, Fungicide and Rodenticide Act, after the U.S. Supreme Court in June 2026 sided with Bayer on Roundup in ruling FIFRA preempts state failure-to-warn laws.

"Independent of any labeling or packaging requirement under FIFRA, the product and distributor defendants had duties under California law, as alleged below, to design and formulate a reasonably safe product, to adequately test chlorpyrifos, and to disclose chlorpyrifos's known and

knowable neurological risks through non-labeling channels," the lawsuit said.

"Those duties could have been satisfied without changing chlorpyrifos's EPA-approved label or packaging."

Chlorpyrifos was first registered for use as a pesticide in the U.S. in 1965. In June 2000, following concerns regarding the health and environmental risks associated with chlorpyrifos exposure, the EPA announced an agreement with chlorpyrifos registrants to eliminate, phase out or modify certain uses while permitting continued agricultural uses. The EPA in 2002 required additional safety measures, including restrictions on application rates, buffer zones intended to protect water quality and wildlife, and increased personal protective equipment requirements for agricultural workers.

In 2024, the EPA announced new measures designed to protect threatened or endangered species from the effects of chlorpyrifos.

The EPA continues to review the pesticide's registration and currently allows it to be used on soybeans, wheat, alfalfa, apples, asparagus, tart cherries, citrus, cotton, peaches, strawberries and sugar beets.

Chlorpyrifos is an organophosphate insecticide commonly used on agricultural crops and on nonfood sites such as ornamental plants in nurseries, golf course turf or as wood treatment.

The lawsuit is at least the second filed in California in recent weeks making failure-to-warn claims that are not tied directly to EPA-approved labels under FIFRA. Syngenta faces a similar suit over atrazine, as DTN reported in October: https://www.dtnpf.com/…

Read more on DTN:

"EPA Further Restricts Chlorpyrifos Use," https://www.dtnpf.com/…

"Court Tosses EPA Chlorpyrifos Action," https://www.dtnpf.com/…

Todd Neeley can be reached at todd.neeley@dtn.com

Follow him on social platform X @DTNeeley

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