Air Pollution Linked to Higher Brain Tumor Risk

Long-term exposure to tiny airborne particles may increase the risk of meningioma, a new study finds.

Daily exposure to polluted air might pose a greater threat than previously understood, especially concerning brain health. Research from Denmark suggests a link between extended exposure to air pollution and an elevated risk of meningioma, a typically non-cancerous brain tumor.

Meningioma Risk and Air Quality

The Danish study, featured in *Neurology*, monitored nearly four million adults over 21 years. Higher air pollution levels correlated with increased meningioma risk, specifically regarding ultrafine particles. Approximately 16,600 participants developed central nervous system tumors; 4,600 of those were meningiomas.

Meningioma Defined

Meningiomas, the most frequent primary brain tumor type, are usually benign. Nonetheless, their growth can compress brain tissue, nerves, or blood vessels, causing neurological issues like vision impairment, seizures, or headaches. Their slow progression often means they remain undetected for extended periods.

The Role of Ultrafine Particles

Researchers gauged pollution levels in participants’ neighborhoods to assess long-term exposure. They focused on traffic emissions, diesel fumes, and ultrafine particles from vehicle exhaust and smoke. The study revealed a connection between higher pollution levels and meningioma risk, particularly for those exposed to ultrafine particles. A link to more aggressive tumors, like gliomas, was not found.

“While research on the health effects of ultrafine particles is still in its early stages, these findings point to a possible link between traffic-related ultrafine particle exposure and the development of meningioma,”

—Dr. Ulla Hvidtfeldt, Senior Scientist at the Danish Cancer Institute

How Air Pollution Impacts Brains

While the study doesn’t prove direct causation, it reinforces evidence suggesting airborne pollutants breach the blood-brain barrier. This may trigger inflammation or brain tissue damage. Similarly, a 2024 study found that long-term exposure to air pollution is associated with a higher risk of developing dementia (Alzheimer’s Association).

Other Meningioma Risk Factors

The precise cause of meningiomas remains unclear. Additional identified risk factors encompass:

• Radiation exposure, particularly in childhood
• Hormonal influences (more prevalent in women)
• Genetic disorders like Neurofibromatosis type 2 (NF2)

This research highlights the potential impact of environmental factors, such as air quality, on meningioma development. The study’s limitations included estimating pollution exposure based on outdoor air quality in residential zones without considering time spent indoors. Further research is needed to validate these findings and assess whether reducing air pollution could decrease brain tumor risks.