Prenatal aerosol exposure and neonatal cord blood hepatic enzyme activities in a highly polluted urban area.
Ambient aerosol pollution during pregnancy has been linked to adverse neonatal outcomes, but the relative importance of exposure timing versus intensity remains uncertain. This study investigated associations between maternal ambient aerosol exposure and neonatal cord blood hepatic enzyme activities among 92 newborns in Ahvaz, Iran, a city with severe particulate pollution. MODIS AOD data were used to estimate exposure across all gestational months. Cord blood biomarkers measured included ALT (21.1 ± 9.7 µ/l), AST (29.4 ± 11.3 µ/l), ALP (473.2 ± 105.8 µ/l), and GGT (147.9 ± 103.8 µ/l). Principal Component Analysis and Generalized Linear Models, adjusted for maternal age and infant sex, showed that cumulative exposure (PC1, 48.23% variance) and peak aerosol events (PC2, 13.58% variance) significantly increased several biomarkers (ALT: β = 0.631, p = 0.004; GGT: β = 6.996, p < 0.001). AST was marginally associated with cumulative exposure and significantly related to maternal age. Infant sex influenced GGT levels, while trimester-specific exposure showed limited effects. Overall, cumulative and peak aerosol exposures were found as the primary exposure patterns associated with altered neonatal cord blood hepatic enzyme activities, underscoring the need to reduce sustained and high-intensity pollution to protect fetal health.