Air pollution not only affects the cardiovascular and respiratory systems: it could also impact the brain.
This is indicated by a recent study published in the journal Neurology, conducted by scientists from the Danish Cancer Institute and the Technical University of Munich, linking exposure to ultrafine traffic particles with a higher risk of developing meningiomas, the most common brain tumor in adults.
Meningiomas: slow but potentially disabling tumors
Meningiomas are primary tumors that develop in the membranes surrounding the brain and spinal cord. Although rarely considered cancerous, they can cause neurological disabilities by pressing on nerves, blood vessels, and brain tissue.
In the study:
- Data from 4 million Danish adults over 21 years were analyzed
- Of the cases recorded, 4,600 people developed meningiomas
- Prolonged exposure to pollutants such as diesel emissions and vehicular smoke was compared
Urban pollutants and brain risk
The research found that those who were most exposed to ultrafine particles from exhaust pipes, smoke, and traffic had a higher likelihood of developing meningiomas, although there was no direct correlation with more aggressive brain tumors such as gliomas.
“Air pollution can affect the brain, not only the heart and lungs,” stated Ulla Hvidtfeldt, co-author of the study.
These particles — so small that they can cross the blood-brain barrier — have previously been linked to brain damage and cognitive impairments.
Limitations and future of research
The authors pointed out that the study has some limitations:
- It was based on measurements of outdoor air in neighborhoods, without considering occupational exposure or time indoors
- It does not demonstrate causality, but an epidemiological correlation that needs further exploration
Nevertheless, the results support the hypothesis that reducing air pollution could have neuroprotective benefits, in addition to the already known benefits for pulmonary and cardiovascular health.
“Cleaning the air could help reduce the risk of brain tumors. It would be a real advance for public health,” concluded Hvidtfeldt.
