Impact of placental polycyclic aromatic hydrocarbons accumulation on neonatal birth outcomes

Although polycyclic aromatic hydrocarbons (PAHs) are recognized for their carcinogenic, teratogenic, and genotoxic properties, there is a lack of scientific evidence detailing impact of in-utero exposure to PAHs on adverse birth outcomes. Present study is planned to fill this research gap by investigating placental levels of 16 USEPA Priority PAHs and associated health risks for infants. Placental tissue samples were collected from 200 pregnant population and infant anthropometric measures like birth height, weight and head circumference were collected from pediatrician records. Benzo(a)pyrene (23%) and Chrysene (16%) were two major PAHs detected in collected samples with dominance of high molecular weight PAHs compounds in compare to that of low molecular weight ones. In addition, all 16 PAHs were recorded higher (significantly higher levels of chrysene and benzo(k)fluoranthene) in placental tissues of mothers delivering low birth weight infants (<2500 g) than normal birth weight infants (≥2500 g). Results of multivariable regression analysis indicated inverse association between PAHs and birth height, weight, head circumference while positive association with cephalization index (p < 0.05). None of PAHs was found to be affecting ponderal index of infants. These results collectively imply that exposure to PAHs from environment is linked to inadequate fetal development and provide foundation for future studies exploring potential biological mechanisms by which PAHs mediate affect on infants' anthropometric measures.