Prenatal Exposure to [Formula: see text] Oxidative Potential and Lung Function in Infants and Preschool- Age Children: A Prospective Study

BACKGROUND: Fine particulate matter ([Formula: see text]) has been found to be detrimental to respiratory health of children, but few studies have examined the effects of prenatal [Formula: see text] oxidative potential (OP) on lung function in infants and preschool children. OBJECTIVES: We estimated the associations of personal exposure to [Formula: see text] and OP during pregnancy on offspring objective lung function parameters and compared the strengths of associations between both exposure metrics. METHODS: We used data from 356 mother–child pairs from the SEPAGES cohort. PM filters collected twice during a week were analyzed for OP, using the dithiothreitol (DTT) and the ascorbic acid (AA) assays, quantifying the exposure of each pregnant woman. Lung function was assessed with tidal breathing analysis (TBFVL) and nitrogen multiple-breath washout ([Formula: see text]) test, performed at 6 wk, and airwave oscillometry (AOS) performed at 3 y. Associations of prenatal [Formula: see text] mass and OP with lung function parameters were estimated using multiple linear regressions. RESULTS: In neonates, an interquartile (IQR) increase in [Formula: see text] ([Formula: see text]) was associated with a decrease in functional residual capacity (FRC) measured by [Formula: see text] [[Formula: see text]; 95% confidence interval (CI): [Formula: see text] , 0.15]. Associations with [Formula: see text] showed similar patterns in comparison with [Formula: see text] but of smaller magnitude. Lung clearance index (LCI) and TBFVL parameters did not show any clear association with the exposures considered. At 3 y, increased frequency-dependent resistance of the lungs ([Formula: see text]) from AOS tended to be associated with higher [Formula: see text] ([Formula: see text]; 95% CI: [Formula: see text] , 0.24) and [Formula: see text] ([Formula: see text]; [Formula: see text]; 95% CI: [Formula: see text] , 0.27) but not with [Formula: see text] ([Formula: see text]; [Formula: see text]; 95% CI: [Formula: see text] , 0.16). Results for FRC and [Formula: see text] remained similar in OP models adjusted on [Formula: see text]. DISCUSSION: Prenatal exposure to [Formula: see text] was associated with several offspring lung function parameters over time, all related to lung volumes. https://doi.org/10.1289/EHP11155