Medscape Medical News
Residential Proximity to Golf Courses Linked to Parkinson’s Disease
Pauline Anderson
May 09, 2025
Living within a mile of a golf course is associated with a 126% increased risk for Parkinson’s disease (PD), possibly due to increased pesticide exposure, results of a population-based case-control study suggest.
Results also showed drinking water from groundwater service areas with a golf course was associated with almost a twofold increased risk for the disease.
Brittany Krzyzanowski, PhD
The study results imply that both vulnerable drinking water and airborne pollutant exposure may contribute to the risk of developing PD near golf courses, study investigator Brittany Krzyzanowski, PhD, assistant professor, Barrow Neurological Institute, Phoenix, told Medscape Medical News.
However, she cautioned that because the study is observational it cannot establish causality, so it is too early to recommend that individuals move away from golf courses.
Nevertheless, she added, the results suggest individuals should be aware of the potential risk and take steps to minimize their exposure.
The study was published online on May 8 in JAMA Network Open.
Novel Research
PD is likely caused by a complex interaction between genetic predisposition and environmental factors, including pesticide exposure. Previous research showed pesticides such as paraquat and rotenone induce Parkinson-like neurodegeneration in the substantia nigra, primarily through mechanisms involving oxidative stress, mitochondrial dysfunction, and dopaminergic neuron apoptosis.
Golf courses are frequently treated with pesticides to uphold the visual and maintenance standards of putting greens and fairways. In the United States, the amount of pesticide used on golf courses can be up to 15 times greater than that in European countries.
One anecdotal report has suggested that living near golf courses may increase the risk for PD. However, few studies have explored the role of pesticide exposure from golf courses on PD risk, said Krzyzanowski.
Using the Rochester Epidemiology Project (REP) medical records linkage system, researchers identified patients with PD in Olmstead County, Minnesota, from 1991 to 2015. From medical records, a movement disorder specialist confirmed the PD diagnosis as well as the date of onset.
Investigators used home addresses 2 or 3 years prior to PD symptom onset to allow for a delay between potential environmental exposure and development of PD. Address-level data provide the most accurate distance-to-exposure values.
The study included 419 individuals with PD, median age of 73 years at diagnosis and 61% men, who were compared with 5113 age- and sex-matched control individuals without the disease.
Researchers collected data on 139 golf courses in the 27-county study region. Using satellite imagery, they manually digitized golf course data to confirm the correct placement of golf course boundaries in 2013, the earliest year relevant data were available.
After adjusting for age, sex, race and ethnicity, index year (date of PD symptom onset for cases), household income, and urban or rural category, the study found living within one mile of a golf course was associated with 126% increased odds of PD (adjusted odds ratio [aOR], 2.26; 95% CI, 1.09- 4.70; P = .03) compared with those living more than 6 miles from a golf course.
The analysis uncovered a modest dose response. The odds of PD increased by 198% at 1-2 miles (aOR, 2.98; 95% CI, 1.46-6.06; P = .003), 121% at 2-3 miles (aOR, 2.21; 95% CI, 1.06-4.59; P = .03), and 92% at 3-6 miles (aOR, 1.92; 95% CI, 0.91-4.04; P = .09) compared with those living more than 6 miles away.
Contaminated Drinking Water?
A sensitivity analysis showed the link between proximity to golf course and PD was stronger in urban areas. The authors speculate that greater density surrounding golf courses in urban areas may lead to higher levels of airborne pollutant exposure to nearby residents.
Researchers also assessed whether individuals received their drinking water from groundwater sources located either with, or without, a golf course or from private wells. Overall, 77.3% of the study population lived in areas served by groundwater-based water systems. They noted that pesticides used on golf courses can seep into groundwater, potentially contaminating drinking water supplies.
Results showed that individuals receiving tap water from groundwater service areas with a golf course had nearly a twofold increased risk for PD compared with those in groundwater areas without golf courses (aOR, 1.96; 95% CI, 1.20-3.23). They also had a 49% higher risk for PD than those using private wells as a drinking water source (aOR, 1.49; 95% CI, 1.05-2.13).
The researchers acknowledged the water distribution process is complex and varies from city to city, so it’s possible not everyone within the same water service area shared the same water source.
The investigators also determined whether water services areas were within a vulnerable groundwater region, defined as those with coarse texture soils, shallow bedrock, or karst geology.
Krzyzanowski explained that karst topography describes a region with limestone bedrock that slowly dissolves over time, creating underground voids that allow water from the surface to move more rapidly through it.
“This means that pesticides applied to grass or crops can more readily move into the groundwater supply after a rain,” the investigators noted.
The analysis showed that individuals whose tap water was from service areas with a golf course located in vulnerable groundwater regions were 82% more likely to have PD compared with those in similar areas with a golf course but nonvulnerable groundwater (aOR, 1.82; 95% CI, 1.09-3.03).
Study limitations included the restricted geographic scope of the population-based dataset and the predominantly White study population. In addition, the lack of occupational history data may have led to exposure misclassification, as some individuals may have spent significant time away from their home address. The study also did not account for other relevant risk factors for PD, such as head trauma or genetic predisposition.
Experts Weigh In
Commenting on the findings, David Dexter, PhD, director of Research, Parkinson’s United Kingdom, raised a number of other potential limitations of the study.
In a statement from the Science Media Center, which features expert comment on science news, Dexter noted the study didn’t restrict participants to those who lived permanently in the area, an important consideration as PD starts in the brain 10-15 years before diagnosis.
“This would not only affect participants’ exposure but also suggests their Parkinson’s could have started before they moved around a golf course,” he said.
Dexter also noted that 80% of individuals with PD lived in urban areas compared with only 30% of control individuals, so other factors such as air pollution from motor vehicles could have accounted for some of the increased incidence of the disease. He also noted that the drinking water wasn’t analyzed for pesticide levels.
Commenting on the research for Medscape Medical News, Michael S. Okun, MD, Adelaide Lackner professor of Neurology, University of Florida, and executive director, Norman Fixel Institute for Neurological Diseases, both in Gainesville, Florida, said the study’s findings “highlight a clear and urgent need to re-evaluate pesticide use on golf courses.”
Okun, who is also medial advisor for the Parkinson’s Foundation said the link between proximity to golf courses and increased PD risk is “striking.”
“These results raise concerns about how chemicals applied for aesthetics may silently shape neurological health,” he said. The fact that pesticides used to keep golf courses pristine may be seeping into local water supplies and increasing PD risk “is a hidden hazard we can no longer ignore,” said Okun.
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