Association of exposure to polycyclic aromatic hydrocarbons during pregnancy with autism spectrum disorder-related behaviors in toddlers: a birth cohort study

Abstract:

Objective To study the association of exposure to polycyclic aromatic hydrocarbons (PAH) during pregnancy and autism spectrum disorder (ASD)-related behaviors in toddlers. Methods A total of 348 toddlers who had accepted the measurement of PAH-DNA adduct in umbilical cord blood and evaluation of behavior problems at the age of 36 months were enrolled in this birth cohort study. Child Behavior Checklist (CBCL) and Autism Behavior Checklist (ABC) were used to evaluate behavior problems at the age of 36 months. The correlation of the concentration of PAH-DNA adduct in umbilical cord blood with CBCL and ABC scores at the age of 36 months were analyzed. Results The detection rate of PAH-DNA adduct in umbilical cord blood was 52.3%, and the median concentration was 0.68 ng/mL. The median total scores of CBCL and ABC scales were 23 and 8 respectively. In children aged 36 months, the concentration of PAH-DNA adduct was positively correlated with the score of social withdrawal in the CBCL scale (r_s=0.205, P < 0.05), the total score of the ABC scale (r_s=0.412, P < 0.05), and the selfcare score of the ABC scale (r_s=0.355, P < 0.05). The concentration of PAH-DNA adduct was closely associated with the total score of the ABC scale in children aged 36 months (β=0.122, P < 0.05). Conclusions PAH exposure during pregnancy may be a risk factor for ASD-related behaviors in toddlers. Effective reduction of PAH exposure during pregnancy and detection of PAH-DNA adduct in neonatal umbilical cord blood are of vital importance for early prevention, screening and intervention of ASD.