spoiler

Living within one mile of a golf course doubles the risk of developing Parkinson’s, a new study suggests.

US researchers believe pesticides used to keep greens and fairways in immaculate condition could be triggering the condition by leaching into water supplies or becoming airborne.

In new research, a team from the Barrow Neurological Institute, Arizona analysed health data from people living near 139 golf courses in southern Minnesota and western Wisconsin.

They discovered that living within one mile of a golf course was associated with a 126 per cent higher risk of developing Parkinson’s compared with individuals living more than six miles away.

The study also found a linear relationship between the chance of developing Parkinson’s and distance from the greens, with each mile away reducing the chances of diagnosis by 13 per cent.

Writing in the journal Jama Network Open, Dr Brittany Krzyzanowski said: “These findings suggest that pesticides applied to golf courses may play a role in the incidence of Parkinson’s disease for nearby residents.

“Public health policies to reduce the risk of groundwater contamination and airborne exposure from pesticides on golf courses may help reduce risk of Parkinson’s disease in nearby neighbourhoods.”

The overall chance of developing Parkinson’s is small, with about 0.005 per cent of people in their 30s diagnosed, rising to about 1.7 per cent of people in their 80s.

Previous studies have suggested that exposure to pesticides such as organophosphates raise the risk of the condition, and in 2011 the US National Institutes of Health warned that rotenone and paraquat in particular multiply the risk of Parkinson’s by 2.5.

That study found the pesticides can inhibit the function of the mitochondria, the structure responsible for making energy in the cell, as well as causing oxidative stress that can harm cellular structures. Seven pesticides in groundwater

There is also evidence that pesticides from golf courses can pollute groundwater. A study of water courses surrounding four different golf courses in Cape Cod, Massachusetts discovered that they were contaminated with seven different pesticides including those linked to Parkinson’s.

But although there has been anecdotal evidence that living near golf courses may increase the chance of Parkinson’s and cancer, there have been no major studies until now.

The latest research looked at nearly 4,500 people who lived in the vicinity of golf courses, including 418 Parkinson’s patients.

It found a clear link for those living within three miles of a golf course, with the risk decreasing as people moved farther away. The effects were strongest in residential areas that shared their groundwater with a golf course.

Britain has traditionally used fewer pesticides on golf courses than the US, and recently banned the most harmful chemicals.

Experts at the charity Parkinson’s UK also pointed out the disease starts in the brain 10 to 15 years before diagnosis, so the seeds may have been planted long before people moved near a golf course.

Dr Katherine Fletcher, the research lead at Parkinson’s UK, said: “Parkinson’s is complex. The causes of the condition are unclear and are likely to involve both genetic and environmental factors.

“Many studies have investigated whether pesticides increase the risk of developing Parkinson’s in different populations around the world. The results have been varied, but overall suggest that exposure to pesticides may increase the risk of the condition.

However, the evidence is not strong enough to show that pesticide exposure directly causes Parkinson’s. In Europe and the UK, the use of pesticides is strictly controlled, and some – like paraquat – are banned, due to concerns about their wider health and environmental impacts.

“So, the risk of exposure to these for most people is extremely low.”