Breathing in tiny air pollution particles could increase the risk of Parkinson’s disease, scientists have found.
Exposure to tiny particles of fumes emitted from car exhausts and burning wood are thought to trigger inflammation in the body that that could spark the disease — which affects some 8.5million people globally.
Parkinson’s is the fastest-growing neurological condition in the world, affecting two per cent of the population over 70-year-old with figures set to triple in the next two decades.
But it’s thought that as many as 20 per cent of people with Parkinson’s — caused by a loss of brain cells that produce vital chemicals — experience symptoms before they are 50.
According to neurologist Dr Anh-Thu Vu, Parkinson’s was traditionally found in people over the age of 60, but it is increasingly common in younger people.
Now, a team of US experts have published findings that suggest one possible theory for the rise could be air pollution.
According to neurologist Dr Anh-Thu Vu, Parkinson’s was traditionally found in people over the age of 60, but it is increasingly common in younger people
Exposure to tiny particles of fumes emitted from car exhausts and burning wood are thought to trigger inflammation in the body that that could spark the disease — which affects some 8.5million people globally
The US study identified 346 Parkinson’s patients in Minnesota who were diagnosed with the disease between 1991 and 2015.
These patients were then divided into two subgroups; those with faster cognitive deterioration and slower movement, and those with a tremour.
Researchers calculated mean annual PM2.5 levels in the atmosphere — pollutant particles smaller than 2.5 micrometers — from 1998 to 2019 and nitrogen dioxide levels between 2000 and 2014.
Levels of pollution were then analysed at the participants home addresses within a 1km area.
PM2.5 are soot particles in the air invisible to the human eye that can enter into blood and penetrate deep into the lung.
Knowing the symptoms of Parkinson’s can lead to earlier diagnoses and access to treatments that improve the quality of life of patients
They can be emitted by vehicle engines, wood burning and smoking.
Although small, these particles are thought to cross the blood brain barrier in humans leading to inflammation, oxidative stress, and activated microglia — a cell that can cause inflammation — which can trigger the development of Parkinson’s.
Data suggested higher levels of this type of pollution is associated with Parkinson’s, compared with lower levels of exposure.
Researchers also found there was a 36 per cent increased risk of akinetic rigid — a type of Parkinson’s that can cause faster cognitive deterioration and slower movement — presentation of the disease, causing faster cognitive deterioration in memory.
Additionally, higher levels of PM2.5 and NO2 were associated with an increased risk of developing dyskinesia — a side effect of Parkinson’s that causes involuntary or uncontrolled muscle movements, according to Parkinson’s Foundation.
Study authors warn the findings of this study suggest that a reduction in air pollution may help reduce Parkinson disease risk.
In 2024, the US Environmental Protection Agency reduced the annual PM2.5 standard by a quarter due to growing evidence of negative health effects.
Study authors said: ‘Our study not only supports the findings that led to this change, but suggests that the upper limit should be lowered to 8 μg/m3 — a level previously advocated for by the American Lung Association and other health organizations.
‘Notably, the World Health Organization recommends a more stringent limit than this, setting their standard to 5 μg/m3.’
Doctors have found Parkinson’s is increasingly common in people under 50, known as young-onset Parkinson’s disease.
Symptoms include tremors of the hands, arms, legs, jaw and face, rigidity of the limbs and torso, slowed movement and impaired balance and coordination.
Sufferers may also experience depression, insomnia and cognitive problems.
In rare instances, Parkinson’s-like symptoms can appear in children and teenagers.
This form of the disorder is called juvenile Parkinsonism and is often associated with specific genetic mutations, according to Parkinson’s Foundation.