Scientists and health officials are still working to discern exactly how air pollutants interact with the brain.

“We speculate that air pollution probably puts greater damage on the white matter in the brain, which is associated with language ability,” says Xin Zhang, a study author and researcher at Beijing Normal University's school of statistics.

“More research is needed to understand the mechanisms,” notes Zhang.

While the Chinese study highlights an important link, it will need to be replicated to quantify how air pollution changes the brain, says Jonathan Samet, dean of the Colorado School of Public Health. Only in the past decade has research on air pollution and brain health intensified, he says, noting that how particles enter and