Air pollution could be to blame for Parkinson’s disease, a new study has suggested.
Intriguing research has found that those living in heavily polluted cities are at higher risk of developing the incurable and progressive condition.
Those with a higher genetic Parkinson’s risk living in such areas were also up to three times more likely to be diagnosed with the brain disorder, according to the study.
Exposure to tiny particles of fumes emitted from car exhausts and burning wood are thought to trigger inflammation in the body that could spark the condition — which affects movement, and blights some 150,000 Brits.
For the study, US scientists tracked over 3,000 adults in two separate experiments.
The average levels of carbon monoxide (CO) that was directly emitted from vehicle engines close to participants’ homes were assessed.
Also taken into account were other common pollutants from cars including unburned hydrocarbons (HC), carbon monoxide (CO), nitrogen oxides (NOx) and particulate matter (PM).
Factors that could skew the results, such as food allergies and smoking status, were also accounted for.
Research suggests people living in heavily polluted cities are at higher risk of developing the incurable condition
Symptoms can include uncontrollable tremors, slow movements and muscle stiffness, but experts say they often only appear when about 80 per cent of the nerve cells have been lost
In the first study, researchers at the University of California, Los Angeles, tracked over 1,300 adults who had lived in California for at least five years.
They found high levels of traffic-related air pollution put people at 28 per cent higher risk of developing Parkinson’s.
The second tracked more than 2,000 adults, more than half of whom lived in Copenhagen or provincial cities in Denmark.
Here, they discovered high traffic air pollution ‘nearly tripled the risk’ of the disease.
Combining the results of both studies, they determined that, on average, those who live in areas with high levels of traffic-related air pollution are at nine per cent greater risk.
Writing in the journal JAMA Network Open, the researchers said: ‘Notably, joint effects of both risk factors were much more pronounced, with Parkinson’s risk increasing up to 3-fold in genetically susceptible individuals exposed to high traffic-related air pollution levels.’
Study authors suggested that a reduction in air pollution may help reduce Parkinson’s disease risk.
This map shows the 10 areas with highest levels of air pollution recorded in 2023. These areas had almost double or triple the levels of of particulate matter, recommended by the World Health Organization
The World Health Organization has long demanded countries take tougher action to combat the scourge of pollution, which is thought to kill 7million people every year globally.
Parkinson’s affects around 153,000 people in the UK and 500,000 Americans.
Every hour, two people are diagnosed with the condition in the UK and the disease costs the NHS more than £725million a year.
Early signs of the condition include a tremor, stiffness, slowness of movement, and loss of smell.
Balance problems such as issues with coordination and muscle cramps are other common signs.
But it is a poorly understood condition which sees nerve cells in the brain that produce the vital hormone dopamine die off.
While there is no cure, treatments are available to manage symptoms and maintain quality of life for as long as possible.
The condition places great strain on the body which in turn leaves a person vulnerable to deadly infections.
