Prenatal polycyclic aromatic hydrocarbons exposure and child growth and adiposity: A longitudinal study

Background: Exposure to polycyclic aromatic hydrocarbons (PAHs) during childhood has been associated with altered growth and adiposity in children. The effects of prenatal exposure to PAHs on developmental programming of growth and adiposity are still unknown.

Objective: To study the association of prenatal exposure to PAHs with early childhood growth and adiposity measures.

Methods: In NYU Children's Health and Environment Study (2016-2019), we studied 880 mother-child pairs for maternal urinary PAH metabolites in early, mid, and late pregnancy and measured child weight, length/height, triceps, and subscapular skinfold thicknesses at 1, 2, 3, and 4 years. We used linear mixed models to investigate associations between average pregnancy exposure to PAHs and the z-scores of child repeated measures. The models were adjusted for sociodemographic and health-related factors.

Results: Children prenatally exposed to higher levels of PAHs had greater weight and length/height z scores. We found an interaction with time-point of child assessment, showing stronger associations at later ages. For instance, PAH exposure was associated with higher weight z-scores at 3 years: coefficient per Ln-unit increase in 2-NAP=0.25 (95%CI: 0.13, 0.37), 2-PHEN=0.25 (95%CI: 0.11, 0.39), 1-PYR=0.13 (95%CI: 0.02, 0.24), and 4-PHEN=0.09 (95%CI: 0.02, 0.15). Higher concentrations of 2-NAP (coefficient=0.21, 95%CI: 0.11, 0.31), 2-PHEN (coefficient=0.24, 95%CI: 0.12, 0.35), 3-PHEN (coefficient=0.13, 95%CI: 0.02, 0.24]), 4-PHEN (coefficient=0.09, 95%CI: 0.04, 0.15), and 1-PYR (coefficient=0.11, 95%CI: 0.02, 0.21) were associated with higher weight z-score at 4 years.

Conclusion: Prenatal PAH exposure may contribute to the developmental programming of growth in childhood.