Living in the city is exposing each day to a multitude of invisible factors whose long -term effects are still poorly understood. Among them, the quality of the air that we breathe is now the subject of increased attention. If the cardiovascular and respiratory risks linked to pollution are well documented, a new concern is emerging in the field of neurology. Recent studies suggest a plausible link between air pollution and brain tumors, raising fundamental questions about the repercussions of urban lifestyle on our mental and cognitive health.
Experiments in animals have shown that nanoparticles inhaled by the nose can reach the brain via the olfactory nerve. Traces of these particles have also been identified in the cerebral tissues of human subjects that lived near sources of intense pollution. At the cellular level, their presence could promote oxidative stress and mutation mechanisms. These mechanisms are of interest today, specialized environmental health epidemiologists.
Air pollution and brain tumors under the eye of researchers
In Denmark, researchers have conducted the largest study on the subject. For 21 years, they have followed nearly four million adults as part of a national cohort. As a result, the people exposed to the highest concentrations of ultra -fine particles presented a risk of developing meningioma multiplied by three compared to the less exposed. The researchers also measured the impact of several other pollutants such as nitrogen dioxide and fine PM2.5 particles. The data, relayed by Scitechdaily, confirm a disturbing trend that the risk increases with the concentration of pollutants, even at levels that are commonly found in European cities.
Another major study, this time conducted in Canada, confirms these results. Made in Montreal and Toronto, she followed nearly two million residents over a period of 15 years. The researchers observed that an increase of 10,000 ultrafine particles per cube centimeter in the ambient air increased by 11% the risk of developing a malignant brain tumor. This research, published in the Epidemiology journal, thus highlights a significant relationship between urban pollution and tumors of the central nervous system, regardless of other pollutants such as nitrogen dioxide or PM2.5 particles, which did not seem correlated to an increase in risk.
Rethink our environments to preserve our mental and neurological health
In France, the effects of air pollution on health are already considerable. Public Health France estimates that by lowering the concentrations of fine particles and nitrogen dioxide to levels recommended by WHO, one could avoid up to 30,000 new annual cases of asthma in children, and thousands of cases of cardiovascular, metabolic and respiratory diseases in adults. If neurological pathologies were to be integrated into these evaluations, the health assessment would undoubtedly be even more alarming.
Meningiomas, although often mild, represent the most frequent primary brain tumor. Their slow growth makes them difficult to detect at an early stage, and the symptoms – headaches, vision disorders, epilepsy attacks – sometimes appear late. While the scientific community gradually recognizes the role of environmental factors in their appearance, it becomes necessary to reassess the chronic exposure of urban populations to pollution.
Far from being limited to bronchi or arteries, the consequences of the air we breathe now affect our brain. By identifying these emerging risks, researchers trace the contours of a major health issue, then calling for concrete actions to sustainably clean up our urban environment.
With an unwavering passion for local news, Christopher leads our editorial team with integrity and dedication. With over 20 years’ experience, he is the backbone of Wouldsayso, ensuring that we stay true to our mission to inform.
