Associations of Pre- and Postnatal Air Pollution Exposures with Child Behavioral Problems and Cognitive Performance: A U.S. Multi-Cohort Study

BACKGROUND: Population studies support the adverse associations of air pollution exposures with child behavioral functioning and cognitive performance, but few studies have used spatiotemporally resolved pollutant assessments. OBJECTIVES: We investigated these associations using more refined exposure assessments in 1,967 mother–child dyads from three U.S. pregnancy cohorts in six cities in the ECHO-PATHWAYS Consortium. METHODS: Pre- and postnatal nitrogen dioxide ([Formula: see text]) and particulate matter (PM) [Formula: see text] in aerodynamic diameter ([Formula: see text]) exposures were derived from an advanced spatiotemporal model. Child behavior was reported as Total Problems raw score using the Child Behavior Checklist at age 4–6 y. Child cognition was assessed using cohort-specific cognitive performance scales and quantified as the Full-Scale Intelligence Quotient (IQ). We fitted multivariate linear regression models that were adjusted for sociodemographic, behavioral, and psychological factors to estimate associations per 2-unit increase in pollutant in each exposure window and examined modification by child sex. Identified critical windows were further verified by distributed lag models (DLMs). RESULTS: Mean [Formula: see text] and [Formula: see text] ranged from [Formula: see text] and [Formula: see text] , respectively, across pre- and postnatal windows. Average child Total Problems score and IQ were 22.7 [standard deviation (SD): 18.5] and 102.6 (SD: 15.3), respectively. Children with higher prenatal [Formula: see text] exposures were likely to have more behavioral problems [[Formula: see text]: 1.24; 95% confidence interval (CI): 0.39, 2.08; per [Formula: see text] [Formula: see text]], particularly [Formula: see text] in the first and second trimester. Each [Formula: see text] increase in [Formula: see text] at age 2–4 y was associated with a 3.59 unit (95% CI: 0.35, 6.84) higher Total Problems score and a 2.63 point (95% CI: [Formula: see text] , [Formula: see text]) lower IQ. The associations between [Formula: see text] and Total Problems score were generally stronger in girls. Most predefined windows identified were not confirmed by DLMs. DISCUSSION: Our study extends earlier findings that have raised concerns about impaired behavioral functioning and cognitive performance in children exposed to [Formula: see text] and [Formula: see text] in utero and in early life. https://doi.org/10.1289/EHP10248