Now, a new study conducted by researchers from Lancaster University has found that exposure to polluted air can increase the risk of young people developing serious neurological conditions, including Parkinson’s, Alzheimer’s, and motor neuron disease (MND).
“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 parts of the brain,” said researcher Barbara Maher. “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.”
Neurological risks
The researchers scanned the brainstems of 186 participants from Mexico City to see what effect lifelong exposure to contaminated air can have on neurological health.
The researchers observed noticeable changes to two parts of the participants’ brains: the cerebellum and the substantia nigra; the former is responsible for overall body movement while the latter is the source of dopamine production. The researchers say these parts of the brain were sites for nanoparticles related to exposure to air pollution.
The researchers explained that these nanoparticles increase the likelihood of inflammation throughout the brain and can also lead to abnormalities in protein levels, all of which can increase the likelihood of Parkinson’s, Alzheimer’s, and MND.
“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-, aluminum-, and titanium-rich nanoparticles in the brainstem -- specifically in the substantia nigra, and cerebellum,” said Maher.
“The iron- and aluminum-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,” she continued. “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.”
The researchers only examined participants between the ages of 11 months and 27 years old, but their findings showed that there were already signs of neurological degeneration. The team worries about how negative health effects will manifest over time and hopes that efforts will be taken to better control air pollution.