In January 2026, a landmark study from researchers at UCLA Health found that the pesticide chlorpyrifos could be linked to an increased risk of Parkinson’s disease. The study showed that Americans exposed to chlorpyrifos for a long period of time could be over 2.5x more likely to develop Parkinson’s or Parkinson’s-like symptoms.
Published in the medical journal Molecular Neurodegeneration, this was the first study to ever link Parkinson’s with chlorpyrifos specifically. However, researchers have been investigating potential links between Parkinson’s and insecticides like chlorpyrifos since at least the 2000s.
What is chlorpyrifos?
Chlorpyrifos is a common type of organophosphate insecticide mainly known by popular brand names “Dursban”, “Lorsban”, and many others. As an insecticide, chlorpyrifos is primarily designed to kill insects and other pests by attacking their nervous systems.
Once an extremely popular insecticide in America, chlorpyrifos was used for many purposes, such as:
- Home, yard and garden pest control
- Pest control for field crops, like corn and soybeans
- Protecting tree crops, like almonds, apples and oranges
- Landscaping on golf courses and turf farms
- Protecting nurseries and greenhouse flowers
However, in 2000, the U.S. Environmental Protection Agency (EPA) officially banned chlorpyrifos for home and garden use. This decision came shortly after a federal investigation found potential health risks associated with the brand Dursban, especially in children. Today, chlorpyrifos is only available for industrial use in the United States.
If you don’t recognize chlorpyrifos by its official name, this pesticide is also known by dozens of other brand names. These include:
Dursban, Lorsban, Raid Liquid Roach Ant Killer, Scotts ProTurf Insecticides, MosquitoMist, Cobalt, Insecta, Drexel, Durashield CS, Chemisco Roach Control, Pilot, Ortho-Klor, Ortho Dursban, Duraplex TR, Warhawk, Pyrinex, NuFos, Hatchet, Vulcan, Lock-On, Yuma (4E), Govern, Empire, Equity, Bolton, Vesper, Stallion, Voltage Endurx, Pyrofos, Tundra Supreme.
How was chlorpyrifos linked to Parkinson’s disease?
According to the UCLA Health study, long-term exposure to chlorpyrifos—mainly when used in homes and personal gardens—could be associated with “more than a 2.5-fold increased risk of developing Parkinson’s disease.”
To reach these findings, researchers analyzed data from nearly 850 Americans diagnosed with Parkinson’s disease, along with another 850 people without the disease. Then, they examined the behavior of a group of mice exposed to chlorpyrifos pest control spray for an 11-week trial period.
The rats, as researchers discovered, ended up developing similar signs of brain damage as the Parkinson’s disease patients they examined. By the end of the trial, they were experiencing significant movement problems, losing some of the same brain cells that die in Parkinson’s disease patients.
Study findings spark new lawsuits
When the UCLA study came out in early 2026, agricultural workers and homeowners with Parkinson’s after using chlorpyrifos began filing claims against pesticide manufacturers, demanding compensation for their illnesses. As of June 2026, the Parkinson’s lawsuit for chlorpyrifos users is still getting underway, but legal experts believe there may be hundreds of claims currently being filed.
So far, most of these claims are targeting Dow Chemical Company and Corteva Agriscience, makers of the popular brands “Dursban” and “Lorsban.”
File a Parkinson’s disease claim
If you or an immediate family member were diagnosed with Parkinson’s disease after using chlorpyrifos in 2000 or later, you may be entitled to significant compensation from the lawsuit.
Ready for a free case review? Take our online Pesticides eligibility evaluation to see if you may be eligible to file a claim.