Breathing pollution could be changing your teen’s brain—New study reveals shocking findings

In a recent study published in the journal Environmental Research, researchers in OHSU’s Developmental Brain Imaging Lab found that air pollution is associated with structural changes in the adolescent brain, specifically in the frontal and temporal regions — the areas responsible for executive function, language, mood regulation and socioemotional processing.

Air pollution causes harmful contaminants, such as particulate matter, nitrogen dioxide and ozone, to circulate in the environment. It has been exacerbated over the past two centuries by industrialization, vehicle emissions, and, more recently, wildfires.

While research has established that pollution contributes to various physical health issues like respiratory disorders, cardiovascular diseases and metabolic dysfunction, its effects on neurocognitive health aren’t as well understood.

OHSU researchers leveraged the ABCD Study — the largest longitudinal study of adolescent brain development in the United States — to better understand how exposure to specific air pollutants might affect adolescents, who are undergoing critical periods of brain development and may be especially vulnerable to exposures.

This was one of the first studies to examine air pollution’s impact on structural changes in the adolescent brain over time.

"What we’re discovering is that chronic exposure to common, low-level air pollutants may act like a slow, subtle pressure on the developing brain," said Calvin Jara, M.D., resident in otolaryngology/head and neck surgeries in the OHSU School of Medicine and lead author of the study. "It may not cause symptoms right away, but over time it appears capable of nudging brain development off its typical course, with potential consequences for developmental trajectories and outcomes across the life course."

In an analysis of nearly 11,000 children in the ABCD study dataset, researchers found that baseline exposure to specific air pollutants in the early phase of adolescence, or the onset of puberty, generally ages 9 to 10, was associated with both persistent and developmental changes in cortical thickness, a measurement of the structural maturation of the outer layer of the brain. Atypical cortical thinning, especially thinning that is accelerated, can be an indication of an underlying neurological disruption and result in associated cognitive impairment.

While the issue is more severe in urban areas, researchers note that they’re seeing these changes even in children exposed to pollution at levels below what the Environmental Protection Agency marks as “safe.”

“These data show this is not just about a single child,” Jara said. “It’s about what’s happening to millions of children around the world who are exposed to low levels of air pollution for years on end.”

Researchers warn that these structural changes in the brain could have impacts on a child’s overall health, well-being and life trajectory. Alterations in the development of these critical brain regions could impair attention, memory and emotional regulation, potentially leading to academic difficulties and behavioral concerns. Future research should continue to examine these broader long-term consequences, researchers said.

Combating widespread pollution requires collaborative efforts outside of clinic spaces, researchers note. While individual clinicians can’t directly change air quality, they can educate and advocate for system-level change. Policy efforts aimed at reducing air pollution, including those focused on cleaner transportation and infrastructure, improved access to green spaces and stricter air quality standards, will be critical for promoting healthy brain development, Jara said.

Additionally, clinicians must continually consider the growing role environmental health factors play in their patients’ treatment and care.

“Environmental factors have a huge impact on how healthy children can be, and ultimately how healthy they’ll be over their lifetime,” said Bonnie Nagel, Ph.D., OHSU’s Interim Chief Research Officer, executive vice president and the study’s co-author. “This work adds to the growing body of evidence that pollution is not just an environmental issue; it’s a significant and growing health issue, especially for our youngest and most vulnerable.”