Exploring the Link Between Pollution and Anxiety Disorder

Exposure to air pollution is an established factor in diseases such as asthma and certain heart conditions, and new evidence continues to emerge about pollution’s impact on physiology. In a new study published in Environmental Research, scientists explore the correlation between exposure to traffic-related air pollution (TRAP) and childhood anxiety.

Recent evidence suggests the central nervous system is particularly vulnerable to air pollution. To explore this connection in children, researchers from the University of Cincinnati and Cincinnati Children’s Hospital evaluated brain images of 145 children of an average age of 12 years obtained using magnetic resonance spectroscopy.

The researchers were looking specifically for myo-inositol levels, a naturally occurring metabolite found in glial cells that assists with maintaining cell volume and fluid balance in the brain. Increased my-inositol levels correlate with an increased population of glial cells, a marker of inflammation.

They found that those exposed to higher levels of recent TRAP showed significant increases of myo-inositol in the brain compared to those with lower TRAP exposure. Increases in myo-inositol were also observed to be associated with more generalized anxiety symptoms.

While the researchers note that these observations involve generalized anxiety, not likely to result in a clinical diagnosis of anxiety disorder, they believe that these findings could have important implications. “I think it can speak to a bigger impact on population health ... that increased exposure to air pollution can trigger the brain's inflammatory response, as evident by the increases we saw in myo-inositol," says Kelly Brunst, PhD, assistant professor in the Department of Environmental Health at the College of Medicine, and lead author on the study. "This may indicate that certain populations are at an increased risk for poorer anxiety outcomes."