Even at ‘safe’ levels pollution is damaging children’s brains, Keck researchers find

Mounting evidence is suggesting that even at levels once thought to be ‘safe’, pollution is having an impact on children’s health and brain development. 

 

While air pollution has long been known to contribute to disease, new research from the Keck School of Medicine of the University of Southern California, funded by the US National Institutes of Health and the Environmental Protection Agency (EPA), has shown that even levels of certain pollutants considered safe by the EPA are linked to changes in brain function over time. 

 

Researchers used brain scan data from more than 9,000 participants in the Adolescent Brain Cognitive Development (ABCD) study, the largest-ever nationwide study of youth brain health.  They found that children exposed to more pollutants showed changes in connectivity between various brain regions. In some areas, they had more connections than normal; in other areas, they had fewer.

 

Communication between regions of the brain help humans to navigate virtually every moment of each day, from the way we take in information about our surroundings to how we think and feel. Many of those critical connections develop between the ages of 9 and 12 years of age, and can influence whether children experience normal or atypical cognitive and emotional development.

 

“A deviation in any direction from a normal trajectory of brain development – whether brain networks are too connected or not connected enough – could be harmful down the line,” said first author Devyn L. Cotter, MSc.

 

“Air quality across America, even though ‘safe’ by EPA standards, is contributing to changes in brain networks during this critical time, which may reflect an early biomarker for increased risk for cognitive and emotional problems later in life,” added senior author Megan M. Herting, PhD. 

 

To reach their findings, researchers looked at MRI scans from 9,497 participants in the ABCD study, and compared baseline scans with scans collected two years later. Researchers examined key regions of the brain known to be involved in emotion, learning, memory and other complex functions.

 

Researchers then used other data to map air quality at each child’s residence, and used advanced statistical tools to investigate how air pollution levels relate to changes in brain connectivity over time.

 

To rule out other factors that could explain differences in brain development, the researchers controlled for sex, race/ethnicity, parental education level, household income, urban versus rural location and seasonality, as air pollution varies across winter and summer months. 

 

To review the study findings in full, please see here.