Neighborhood air pollution is associated with attenuated neurocognitive maturation over early adolescence

Adolescence is a key period of neurocognitive maturation. Exposure to high levels of air pollutants has been associated with brain differences in youth, though the relevance of these brain findings to behavioral outcomes such as cognitive development is less clear. In this study, we used the US Environmental Protection Agency's thresholds for unhealthy levels of fine particulate matter (PM_2.5), Ozone (O₃), and NO₂ pollutants to compare youth exclusively exposed to high levels of each pollutant to their respective socioeconomically-matched low-pollution peers over a two-year period in the Adolescent Brain Cognitive Development (ABCD) Study. No youth in the ABCD study were found to be at or above the unhealthy threshold for NO₂. Multivariate analyses showed a consistent neurocognitive latent variable loading positively on cortical functional maturation and task performance, and negatively on cortical grey matter thickness from 9 to 10-11-12 years of age. We found a significant difference in this neurocognitive maturation latent variable over time between the high-pollution (PM_2.5: N = 348, O₃: N = 355) and control groups (PM2.5: N_control=279; O3: N_control=324), such that maturation of cortical networks, increase in task performance, and cortical thinning were significantly higher in the control groups. These results were adjusted for parental income and education and youth's age, sex, race/ethnicity, site, head-motion, scanner, general factor of psychopathology, pubertal status, and area deprivation index, in addition to the socioeconomic matching between high-pollution and control groups. In conclusion, exposure to high levels of PM_2.5 and O₃ is associated with lags in normative neurocognitive maturation in early adolescence.