A large-scale study conducted in California has raised questions about the safety of one of the world’s most widely used pesticides—chlorpyrifos. The research found that people exposed to this chemical for years, whether at work or at home, face nearly triple the risk of developing Parkinson’s disease. This isn’t just a statistic—it’s a real threat to millions, as chlorpyrifos is still widely used on US farmland despite partial restrictions.
Researchers from the University of California, Los Angeles (UCLA) analyzed data from nearly 1,700 people, some of whom had already been diagnosed with Parkinson’s disease. They carefully examined where and how long these individuals had lived and worked, then overlaid this information with official pesticide usage maps dating back to 1974. The results were alarming: the longer and more intense the exposure to chlorpyrifos, the higher the risk.
Those who had worked near fields where the pesticide had been sprayed for decades turned out to be especially vulnerable. For them, the risk of developing Parkinson’s was 2.7 times higher than among those who had rarely been exposed to the chemical. And the danger persisted even years after exposure had ceased—since the disease often develops slowly, its first symptoms may only appear decades later.
How it harms the body
To understand why chlorpyrifos is particularly dangerous, scientists conducted a series of animal experiments. Mice exposed to this pesticide began losing motor skills and suffered a loss of neurons responsible for producing dopamine—a key substance whose deficiency is central to Parkinson’s disease. Their brains developed characteristic protein clumps typically found in patients diagnosed with this condition.
Zebrafish that were also exposed to chlorpyrifos showed disruptions in the autophagy system—a process responsible for clearing cellular debris. When scientists tried to stimulate autophagy, neurons were better protected from damage. This discovery could be the key to new prevention and treatment strategies.
Previous research had already suggested that autophagy plays an important role in the progression of neurodegenerative diseases. Now, it is clear that chlorpyrifos can interfere with this process, accelerating brain cell death. This mechanism explains why even relatively small doses, if exposure is prolonged, can have serious consequences.
A global threat
Chlorpyrifos is banned in the UK and European Union, but in the United States it continues to be used on many farms. Despite stricter regulations, millions of people remain at risk—not only agricultural workers, but also residents of nearby areas. What is particularly concerning is that this chemical has already been linked to developmental brain disorders in children.
The problem is compounded by the fact that Parkinson’s disease develops slowly and has multiple causes. Genetics, sleep quality, even proximity to golf courses (where pesticides are also used)—all of this can affect one’s risk of developing the illness. But now scientists have strong evidence to believe that chlorpyrifos is one of the most dangerous environmental factors.
In the future, researchers plan to study the impact of other pesticides as well as explore whether medications that support autophagy can help protect the brain from damage. For now, we can only speculate how many more people worldwide will encounter the consequences of using this chemical.
In Search of Solutions
The discovery of the mechanism through which chlorpyrifos destroys brain cells offers hope for new methods of prevention and therapy. If scientists can find a way to protect neurons from the disruption of autophagy, there may be a chance to slow or even prevent the onset of Parkinson’s disease in people exposed to pesticides.
However, the situation remains concerning. Despite numerous warnings, chlorpyrifos continues to be used in the agricultural sector, and its traces are still found in food products. The question of a complete ban on this substance in the US and other countries remains unresolved, and each new study only fuels the ongoing public debate.
Even if chlorpyrifos disappears from store shelves, the problem of chemical pollution in the environment will not go away. Scientists are calling for stricter controls over the use of pesticides and a search for safer alternatives to protect the health of future generations.
RUSSPAIN reminds readers that chlorpyrifos is an organophosphate pesticide that has been widely used since 1965 to control pests on agricultural crops and in domestic settings. In recent years, its use has come under heavy criticism due to proven risks to the human nervous system and the environment. In several countries, it has been completely banned, but in the US and some other regions around the world, it is still permitted for use on certain crops. The question of its safety continues to spark intense scientific and public debate.
