Parkinson’s disease was first formally described roughly 200 years ago, when a London physician named James Parkinson wrote about six patients with a peculiar trembling condition he called “the shaking palsy.” By all historical accounts, the condition was rare. Today, it is the fastest-growing neurological disorder on the planet.
Researchers who have studied the disease’s explosive global rise increasingly point to something else, something in the air, soil, water, and on the food we eat. A growing body of evidence now suggests that for most people, Parkinson’s disease prevention is not only possible, but it may also already be within reach. For decades, Parkinson’s was viewed largely as a matter of genetic destiny, bad luck written into the DNA before birth. That picture has changed substantially, and the agents responsible for the shift are hiding in plain sight.
Environmental factors, researchers now argue, don’t just nudge risk upward at the margins. They appear to drive the majority of cases, which is a profoundly different claim than saying that lifestyle choices have some modest benefit.
The Evidence That Environment Drives Most Cases
The global burden of Parkinson’s disease is rising, and large-scale genetic studies have confirmed that extrinsic or environmental factors, rather than genetic predisposition, play the dominant role in its cause. This doesn’t mean genetics are irrelevant – they shape individual vulnerability – but they don’t explain the epidemic.
Parkinson’s disease has been reported as the fastest-growing neurological disorder worldwide in both prevalence and deaths. The age-standardized prevalence increased by 60% between 1990 and 2021, resulting in approximately 11.8 million cases globally. Projections suggest over 12 million cases by 2040.
In the United States, the numbers are just as striking. An estimated 90,000 new cases in people 65 and older are diagnosed annually in the United States alone. In 2022, the World Health Organization published a technical brief outlining the global burden, treatment gaps, and crucial areas for action for Parkinson’s – and included key actions for prevention and risk reduction to reduce its anticipated rise.
The aging of the population explains part of the increase. Aging populations and genetic susceptibility, however, explain only a portion of this growing disease burden. The rest points toward something people are being exposed to – and crucially, something that could be reduced.
Three Culprits Backed by Evidence
Increasing evidence implicates three classes of toxicants in the development of Parkinson’s disease: certain pesticides, the dry-cleaning chemicals trichloroethylene and perchloroethylene, and air pollution. These toxicants are widely prevalent and impair mitochondrial or lysosomal function – the cellular machinery that generates energy and removes waste – or both.
The connection to pesticides is the most thoroughly documented. Paraquat, rotenone, chlorpyrifos, pyrethrins, pyrethroids, and some fungicides are among the chemicals that increase Parkinson’s risk, with dose-response relationships observed – meaning higher exposure correlates with higher risk, not just a statistical blip.
Paraquat deserves particular attention because of how widely it is still used. Paraquat is highly toxic and linked to Parkinson’s disease. Although more than 50 countries have banned it, U.S. farms still apply it regularly. In 2018 alone, 15 million pounds of paraquat were used in the United States.
Chlorpyrifos, another widely used pesticide, carries risk even for people who never work in agriculture. Long-term residential exposure to the pesticide chlorpyrifos is associated with more than a 2.5-fold increased risk of developing Parkinson’s disease, according to researchers at UCLA Health – meaning living near fields where it is sprayed, not just handling it directly, may be enough to matter.
Rotenone, used in both agriculture and aquatic environments, appears to do damage that outlasts the exposure itself. The pesticide rotenone triggers lasting alterations in brain gene activity and epigenetic markers, with changes persisting even weeks after exposure has ended. A 2025 study published in npj Parkinson’s Disease found region-specific epigenomic changes associated with rotenone exposure in the substantia nigra and motor cortex – two of the brain areas most directly damaged in Parkinson’s.
These chemicals don’t stay in the fields. They drift into the air, settle on neighboring properties, and seep into water supplies. Urban and suburban residents are not automatically shielded from agricultural chemical exposure.
The Solvent in the Air You Can’t See
Trichloroethylene (TCE) was once ubiquitous in industrial settings, used to degrease metal parts, in dry-cleaning operations, and in countless manufacturing processes. Most people assume it’s a relic of the past. It isn’t.
TCE is a chemical used in metal degreasing, dry cleaning, and other industrial applications and is a persistent environmental pollutant found in U.S. air, soil, and groundwater. TCE has been identified in at least 1,500 hazardous waste sites regulated under the Comprehensive Environmental Response, Compensation, and Liability Act.
The link to Parkinson’s isn’t new – case reports connecting Parkinson’s disease to occupational TCE exposure appeared as early as 1969, as noted by neurologist Dr. Aaron Ellenbogen of the Michigan Institute for Neurological Disorders. What is new is the scale of the evidence. A study published in Neurology by researchers at Barrow Neurological Institute suggests a potential link between ambient trichloroethylene exposure in outdoor air and Parkinson’s disease risk nationwide – not just among people who worked directly with the chemical, but among people who simply lived and breathed in communities where TCE was present in the environment.
Perchloroethylene, TCE’s chemical cousin, commonly used in dry cleaning, carries a similar risk profile. Both chemicals belong to a family of chlorinated solvents that researchers now believe may be quietly elevating Parkinson’s risk in millions of Americans who have never heard of them.
Air Pollution and the Brain
The third major category is air pollution – specifically fine particulate matter, the microscopic particles emitted by vehicle exhaust, power plants, wildfires, and industrial facilities. Unlike pesticide exposure, which requires some proximity to agricultural or industrial activity, air pollution is near-universal in modern life.
Research published in npj Parkinson’s Disease found that exposure to air contaminants heightens Parkinson’s disease risk, particularly in individuals who are genetically predisposed to higher susceptibility. This gene-environment interaction is important: it suggests that the same level of air pollution may hit some people harder than others, depending on their genetic makeup.
The dose relationship is measurable. A 2025 study found that for each 5 micrograms per cubic meter increase in long-term fine particulate matter (PM2.5) exposure, the odds ratio for Parkinson’s disease increased by 1.10 – a modest but consistent effect that compounds over years of exposure.
This is particularly concerning given how many Americans live in areas that regularly exceed EPA air quality guidelines, and how climate change is intensifying both wildfire smoke and smog conditions.
You can find more about how everyday environmental exposures accumulate in our coverage of U.S. pesticide hotspots and what the maps reveal about where chemical risk is highest.
How These Toxicants Damage the Brain – and What Parkinson’s Prevention Requires
The disease is defined by the death of dopamine-producing neurons in a region of the brain called the substantia nigra. Dopamine is the signaling molecule that coordinates smooth, controlled movement, and when enough of these neurons die, the tremors, rigidity, and slowness that characterize Parkinson’s emerge.
Pesticides like paraquat and rotenone, TCE, and fine particulate matter all appear to converge on the same vulnerability: they impair mitochondrial or lysosomal function – or both – in neurons. Mitochondria generate the energy cells need to survive. Lysosomes clear out cellular debris, including a protein called alpha-synuclein that clumps abnormally in Parkinson’s. When either system fails, neurons become vulnerable to the kind of progressive damage seen in the disease.
Both genetic susceptibility and environmental exposures – including pesticides such as paraquat and rotenone, as well as heavy metals and tobacco smoke – are implicated in Parkinson’s disease development. Genetics shapes individual vulnerability; accumulating environmental exposures, the research increasingly suggests, determine whether that vulnerability becomes disease.
What Reduces the Risk
The same research that identifies environmental culprits also points toward factors that appear protective. Physical activity, healthy dietary patterns, and caffeine intake are among the protective factors against Parkinson’s disease identified in published research.
The evidence for regular physical exercise is consistent across multiple studies. For diet, adherence to healthy dietary patterns – particularly those rich in fruits, vegetables, whole grains, and fish – was consistently associated with reduced Parkinson’s risk in a 2024 systematic review published in Cureus.
Caffeine’s apparent protective effect has drawn considerable scientific attention. At least six large prospective epidemiological studies have firmly established a relationship between increased caffeine consumption and decreased risk of developing Parkinson’s disease, according to a review in The Lancet Neurology. Researchers suggest this effect may be mediated by caffeine’s ability to protect nerve cells and support brain levels of dopamine, the signaling chemical that is deficient in Parkinson’s. This doesn’t mean coffee is a cure, and researchers note some of the observed association may reflect reverse causation – people who later develop Parkinson’s may reduce coffee consumption in the years before diagnosis, complicating the picture.
These lifestyle factors – exercise, diet, and moderate caffeine intake – represent modifiable choices that individuals can act on based on current evidence. Heavy or prolonged toxicant exposure presents a different order of challenge, one that ultimately requires systemic action on pesticide regulation and environmental contamination.
What This Means
Parkinson’s disease could be largely preventable, according to the 2025 analysis published in The Lancet Neurology – a conclusion that would have seemed premature a decade ago. The World Health Organization has recommended reducing exposure to specific environmental factors – in particular pesticides, trichloroethylene, and air pollution – as key actions for Parkinson’s prevention and risk reduction.
On a personal level, that translates to a handful of specific, actionable steps. Choosing organic produce for the crops most heavily treated with paraquat, chlorpyrifos, and rotenone reduces dietary pesticide load. If you live near agricultural land, checking local air quality data and keeping windows closed during high-spray seasons is a reasonable precaution. If your home or neighborhood has any history of industrial dry-cleaning operations or manufacturing sites, checking whether TCE contamination has been reported in local groundwater is worth the five minutes it takes. Indoor air filters rated for volatile organic compounds can reduce exposure to solvents that off-gas from older materials.
Regular vigorous exercise, a diet built around vegetables, whole grains, and fish, and maintaining a healthy weight all consistently appear in the research as factors that lower risk. None of these changes requires a prescription or a specialist. What they require is awareness that Parkinson’s disease is not simply a matter of genetics or bad luck – and that the chemicals surrounding us in daily life are not a minor footnote to that story. They may be the story itself.
Disclaimer: This information is not intended to be a substitute for professional medical advice, diagnosis, or treatment and is for information only. Always seek the advice of your physician or another qualified health provider with any questions about your medical condition and/or current medication. Do not disregard professional medical advice or delay seeking advice or treatment because of something you have read here.
AI Disclaimer: This article was created with the assistance of AI tools and reviewed by a human editor.
Read More: Parkinson’s May Actually Be 7 Different Diseases, New AI Study Finds