Risk assessment and environmental influencing factors of urinary polycyclic aromatic hydrocarbons metabolites in pregnant women in Zunyi, China

Despite the widespread presence and frequent detection of polycyclic aromatic hydrocarbons (PAHs) in various aspects of life, there is limited research on their exposure levels in pregnant women and cumulative exposure from the living environment. This study included 1311 women in late pregnancy from the Zunyi birth cohort and measured the urinary concentrations of 10 hydroxylated PAH metabolites (OH-PAHs). Risk assessment was conducted based on the estimated daily intake to calculate the hazard quotient and hazard index (HI). A linear regression model was used to analyze the relationship between creatinine-adjusted OH-PAHs concentrations and living environment and lifestyle factors, while principal component analysis was applied to trace the sources of PAHs exposure. 1-OHPYR was detected in all participants' urine, with naphthalene metabolites having the highest concentrations among creatinine-adjusted PAHs. OH-PAHs concentrations were associated with housing type, room number, cooking frequency, household size, exercise frequency, fuel type, distance from main road, and drinking water source. Pregnant women using traditional fuels and living in bungalows had higher health risks than those using clean energy and living in buildings. Those living within 100 m of a main road had higher HI than those farther away. Coal combustion was identified as the primary source of PAHs exposure. The study emphasizes the importance of reducing PAHs exposure, especially for pregnant women living in polluted environments. It recommends public health interventions such as improving indoor ventilation and providing clean energy to reduce related health risks.