Fine particulate matter air pollution and longitudinal gray matter development changes during early adolescence: variation by neighborhood disadvantage level.

The adolescent brain is vulnerable to ambient air pollution. Importantly, community-level factors - such as neighborhood disadvantage - that co-occur with air pollution may further enhance this vulnerability and impact brain development. The current study investigated if neighborhood disadvantage moderates the association between residential fine particulate matter (PM) pollution and adolescent brain development, including longitudinal changes in cortical thickness, surface area, and subcortical/white matter volume from ages 9-13 years (n = 8321 participants from the ABCD Study®; 12,634 observations). We found that, in more disadvantaged neighborhoods, higher PM levels were associated with greater age-related cortical thinning in temporal areas and in most regions of the occipital lobe. Furthermore, independent of neighborhood disadvantage, higher PM exposure was associated with larger age-related surface area decreases in parietal, occipital, and temporal regions, but smaller age-related increases in right cerebral white matter volume and frontal and temporal region surface area. Similarly, higher PM exposure was independently associated with greater age-related cortical thinning in the frontal regions, cingulate, and insula, but smaller age-related cortical thickening in temporal regions. Findings have policy implications for air quality improvements alongside investment in disadvantaged neighborhoods to bolster adolescent brain development.