MONDAY, July 14, 2025 (HealthDay News) -- Air pollution, including ultrafine particles (UFP), may be associated with developing meningiomas, according to a study published online July 9 in Neurology.Ulla A. Hvidtfeldt, from the Danish Cancer Institute in Copenhagen, and colleagues examined the possible relationship between air pollution exposure, including UFPs, and tumors of the central nervous system (CNS) in a cohort study including all Danish adults aged 20 years and older identified from nationwide registries since 1991.Data were included for 3,959,619 adults and 16,596 cases of CNS tumors. The researchers found that 10-year mean exposure to UFPs, fine particulate matter (PM2.5), nitrogen dioxide (NO2), and elemental carbon (EC) was associated with the risk for developing meningioma, with confounder-adjusted hazard ratios (95 percent confidence intervals) of 1.10 (1.05 to 1.16), 1.21 (1.10 to 1.34), 1.12 (1.07 to 1.18), and 1.03 (1.00 to 1.05) per interquartile range for UFPs, PM2.5, NO2, and EC, respectively. Air pollution from both local traffic and other sources could be influential. For other CNS groups, the corresponding hazard ratios were not significant."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," Hvidtfeldt said in a statement. "More research is needed to confirm these results, but if cleaning up our air can help lower the risk of brain tumors, that could make a real difference for public health."Abstract/Full Text (subscription or payment may be required).Sign up for our weekly HealthDay newsletter