Risk assessment and environmental determinants of urinary phthalate metabolites in pregnant women in Southwest China

Pregnant women are widely exposed to phthalic acid esters (PAEs) that are commonly used in most aspects of modern life. However, few studies have examined the cumulative exposure of pregnant women to a variety of PAEs derived from the living environmental conditions in China. Therefore, this study aimed to determine the urinary concentrations of nine PAE metabolites in pregnant women, examine the relationship between urinary concentrations and residential characteristics, and conduct a risk assessment analysis. We included 1,888 women who were in their third trimester of pregnancy, and we determined their urinary concentrations of nine PAE metabolites using high-performance gas chromatography–mass spectrometry. The risk assessment of exposure to PAEs was calculated based on the estimated daily intake. A linear regression model was used to analyze the relationship between creatinine-adjusted PAE metabolite concentrations and residential characteristics. The detection rate of five PAE metabolites in the study population was > 90%. Among the PAE metabolites adjusted by creatinine, the urinary metabolite concentration of monobutyl phthalate was found to be the highest. Residential factors, such as housing type, proximity to streets, recent decorations, lack of ventilation in the kitchen, less than equal to three rooms, and the use of coal/kerosene/wood/wheat straw fuels, were all significantly associated with high PAE metabolite concentrations. Due to PAE exposure, ~ 42% ( n = 793) of the participants faced potential health risks, particularly attributed to dibutyl phthalate, diisobutyl phthalate, and di(2-ethyl)hexyl phthalate exposure. Living in buildings and using coal/kerosene/wood/wheat straw as domestic fuel can further increase the risks.