LANCASHIRE, United Kingdom — There’s no shortage of research linking air pollution exposure to adverse health outcomes over time. A new study released by Lancaster University however, is illustrating just how quickly living in a smoggy area can potentially change the course of one’s life. An examination of brainstems among children and young adults living in smoggy Mexico City has uncovered unsettling early markers of Alzheimer’s, Parkinson’s, and ALS.
Moreover, tiny and distinct nanoparticles were also seen in participants’ brainstems. These patients are as young as 11 months-old to 27 years-old. According to the study’s authors, the unique composition of these nanoparticles suggest they come from vehicle pollution like car exhaust.
With this in mind, researchers theorize vehicular air pollution almost certainly puts one at an increased risk of neurological harm.
How smog impacts the brainstem
The brainstem, of course, is an invaluable portion of the human body. It regulates the entire central nervous system, body balancing and positioning, breathing, and heart rate. Suffice it to say, it’s important.
“Not only did the brainstems of the young people in the study show the ‘neuropathological hallmarks’ of Alzheimer’s, Parkinson’s and MND, they also had high concentrations of iron-, aluminium- and titanium-rich nanoparticles in the brainstem – specifically in the substantia nigra, and cerebellum,” says study co-author Professor Barbara Maher in a university release. “The iron-and aluminium-rich nanoparticles found in the brainstem are strikingly similar to those which occur as combustion- and friction-derived particles in air pollution (from engines and braking systems).
“The titanium-rich particles in the brain were different – distinctively needle-like in shape; similar particles were observed in the nerve cells of the gut wall, suggesting these particles reach the brain after being swallowed and moving from the gut into the nerve cells which connect the brainstem with the digestive system,” Maher adds.
Even an 11-month-old infant shows abnormal nerve cell growth and tangles of misfolded proteins in the brain. These observations show clear signs of the formation, aggregation, and propagation of abnormal proteins in smog-exposed young peoples’ brains.
All the participants had experienced lifelong exposure to particulate air pollution. Researchers say this fact constitutes a compelling “smoking gun” when it comes to the neurological impact of air pollution. The case is even more compelling when combined with the association between brain cell damage and the presence of nanoparticles.
Examinations of similarly aged people living in less-polluted areas of Mexico didn’t reveal the same signs of neurological decay.
A pollution pandemic?
Overall, the study’s authors believe their work confirms that metal-rich nanoparticles from air pollution can indeed make their way to the brainstem after being inhaled or swallowed. Once there, they can do serious damage to a number of vital brainstem nerve cells, including the substantia nigra.
Study authors warn it’s quite possible that polluted areas like Mexico City will see a “pandemic” of neurological diseases. This will be more likely in the future as more and more people live to older ages.
“It’s critical to understand the links between the nanoparticles you’re breathing in or swallowing and the impacts those metal-rich particles are then having on the different areas of your brain,” Professor Maher concludes.
“Different people will have different levels of vulnerability to such particulate exposure but our new findings indicate that what air pollutants you are exposed to, what you are inhaling and swallowing, are really significant in development of neurological damage. With this in mind, control of nanoparticulate sources of air pollution becomes critical and urgent.”
The study is published in Environmental Research.