A major long-term study conducted by Harvard T.H Chan School of Public Health has associated tiny air pollution particles with molecular damage linked to Alzheimer’s and Parkinson’s disease.
If this ground-breaking discovery is corroborated by future research, it would have worldwide implications as 90% of the global population live with unsafe air. Medical experts remain sceptical of the findings, as while nanoparticles are a probable cause of the damage, there is doubt over whether this leads to disease later in life.
The study covered over 63 million Americas over a 17-year period and found a higher risk of less common forms of dementia and other neurological disorders in the presence of air pollution.
Microscopic particles known as PM2.5 can be inhaled deep into the lungs, where they irritate the lining, enter the bloodstream and travel to the brain. Even low levels of this particulate matter has been found to be dangerous, particularly to women, white people and urban populations who are notably susceptible.
At every increase of 5 micrograms per cubic metre of air (12 μg/m3) increase in annual PM2.5 concentration, there was a 13% increased risk for first-time hospital admissions both for Parkinson’s and Alzheimer’s, or other related dementias.
This risk remained elevated even below US Environmental Protection Agency’s current supposedly safe guidelines of an annual maximum of 12 μg/m3.
Researchers at the Harvard T.H Chan School of Public Health urged that recommendations need to be tighter.
‘Our study builds on the small but emerging evidence base indicating that long-term PM2.5 exposures are linked to an increased risk of neurological health deterioration, even at PM2.5 concentrations well below the current national standards,’ Xiao Wu, the co-lead author of the study, commented.
‘With the Environment Bill, the UK could commit to adopting a legally binding target to meet the stronger WHO guideline levels for PM2.5 by 2030 at the latest – but it has so far recklessly refused to do so, leaving us all dangerously under-protected,’ Andrea Lee, Clean Air Campaigns Manager at ClientEarth stated.
‘If you measure it, and you understand where the problem is greatest, then you can start to do something. Policy-makers must take account of these findings, and actually begin to work out how we can reduce as much of this exposure to air pollution as possible,’ Professor Barbara Maher at Lancaster University, part of the research team, concluded.