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Introduction: Polycyclic aromatic hydrocarbons (PAHs) are a group of harmful environmental pollutants. People including pregnant women are exposed to PAHs from inhalation, ingestion, and skin absorption. This study aims to examine the association between prenatal PAH exposure and children’s intelligence quotient (IQ) at 5 years of age.

Methods: This is a longitudinal study nested to the population-based cohort, the Maternal and Infant Nutrition Interventions in Matlab, Bangladesh (MINIMat). Maternal urinary PAH metabolites are measured at gestational 8 weeks. Children’s IQ was measured by using the Wechsler Preschool and Primary Scale of Intelligence (WPPSI). Multivariable adjusted linear regression analysis is performed to find the association.

Results: The 3rd quartile of 2- and 3- hydroxyfluorene shows the reduction in scores of VIQ (B= -1.391; 95% CI -2.648, -0.133; p= 0.03), PIQ (B= -1.386; 95% CI -2.726, -0.045; p= 0.043), and FSIQ (B= -1.682; 95% CI -2.918, -0.445; p= 0.008) compared to the 1st quartile.The 2nd and 4th quartiles of hydroxyphenanthrene (sum) also show reduced scores with (B= -1.498; 95% CI (-2.751, -0.244; p= 0.019), and (B= -1.46; 95% CI (-2.719, -0.2); p= 0.023) for VIQ, and (B= -1.376; 95% CI (-2.61, -0.143); p=0.029) and (B= -1.331; 95% CI (-2.571, -0.091); p= 0.035) for FSIQ respectively compared to the reference group. The 2nd quartile of 1-hydroxypyrene shows an increase in PIQ scores (B=1.445; 95% CI 0.107, 2.782; p= 0.034) compared to the 1st quartile.

Conclusion: It can be concluded that prenatal PAH exposure influences children’s IQ at 5 years of age.