Variations, Determinants, and Coexposure Patterns of Personal Care Product Chemicals among Chinese Pregnant Women: A Longitudinal Study

Exposure to mixtures of personal care product chemicals (PCPCs) is commonplace among the Chinese population; yet, limited data are available on the variations, determinants, and coexposure patterns of PCPCs, particularly among pregnant women at multiple time points during gestation. Here, we measured concentrations of 11 most common PCPCs (five parabens, five benzophenones, and triclosan) in 2823 urine samples collected from 941 pregnant women over three trimesters. Based on the quantification results, we calculated the intraclass correlation coefficient (ICC) to assess within-person variability of targeted compounds, applied linear mixed mode models to explore associations between urinary concentrations of PCPCs and exposure-related factors, and used percentile analysis to evaluate exposure to specific or multiple chemicals at one or three trimesters. Seven targeted compounds: methylparaben (MeP), ethylparaben (EtP), propylparaben (PrP), 4-hydroxybenzophenone (4-OH-BP), 2,4-dihydroxybenzophenone (BP-1), 2-hydroxy-4-methoxybenzophenone (BP-3), and triclosan (TCS) were detected in over 66% of samples. The median urinary concentrations (ng/mL) of MeP, EtP, PrP, 4-OH-BP, BP-1, BP-3, and TCS were 15.44, 0.49, 0.61, 0.16, 0.25, 0.53, and 0.48, respectively. We observed that benzophenones (ICC: 0.46-0.55) and triclosan (ICC: 0.50) were less variable than parabens (ICC: 0.35-0.40). Urinary levels of parabens were related to physical activity frequency; urinary levels of benzophenones were associated with the refurbishment of homes and household income, and urinary levels of triclosan were contingent upon the personal basic information (prepregnancy body mass index and age). Notably, higher levels of benzophenones and triclosan but lower paraben levels were observed in summer than in winter. Both coexposure to high percentiles of multiple pollutants at one trimester and exposure to one pollutant at high-dose through three trimesters were rare in the study population. Our findings suggest that these exposure-related factors should be taken into consideration, and health risks should be assessed on mixtures of pollutants in future epidemiological studies.