Sources of outdoor air pollution exposure and child brain network development across the United States
Article
Bottenhorn, KL, Sukumaran, K, Del Giacco, AC et al. (2026). Sources of outdoor air pollution exposure and child brain network development across the United States
. JOURNAL OF ENVIRONMENTAL PSYCHOLOGY, 114 10.1016/j.jenvp.2026.103166
Bottenhorn, KL, Sukumaran, K, Del Giacco, AC et al. (2026). Sources of outdoor air pollution exposure and child brain network development across the United States
. JOURNAL OF ENVIRONMENTAL PSYCHOLOGY, 114 10.1016/j.jenvp.2026.103166
Ambient fine particulate matter (PM2.5) pollution is a heterogeneous mixture of neurotoxic chemicals. Neuroimaging studies have linked childhood PM2.5 exposure to altered brain morphology, microarchitecture, and function, with implications for cognition and psychopathology. However, this literature is largely cross-sectional and often considers PM2.5 a single pollutant, rather than a mixture of chemicals from different sources. Here, we address these gaps by leveraging exposure estimates for six data-derived PM2.5 sources, and longitudinal neuroimaging data from the large, multi-site Adolescent Brain Cognitive Development Study in the United States. We used a predictive modeling approach to assess cross-sectional exposure-related differences in functional brain network connectivity (FC) during childhood (ages 9-11 years; N = 6291) and explore exposure-related changes in FC during the transition to adolescence (ages 9-13 years; N = 1972) for each source of PM2.5, as well as their cross-site generalizability. Instead of highlighting a few networks particularly sensitive to exposure, these analyses identified themes in consistently exposure-related connectivity of sensorimotor networks and the triple network model. Exposure-related differences in visual, auditory, and somatomotor network connectivity related to traffic, crustal materials, ammonium nitrates, and total PM2.5 were consistent with prior epidemiological reports of exposure-related auditory, visual, and motor difficulties. Connectivity of higher-order associative networks in the “triple network model” of psychopathology was largely related to secondary aerosols (i.e., ammonium sulfates, nitrates), consistent with potential links to mental health conditions that may arise later in adolescence or adulthood. While these analyses identified consistent exposure-related FC patterns across iterations, they did not generalize well to data from held-out sites (i.e., mean R2 < 0), especially in the western United States.
