Exposure levels and determinants of placental polybrominated diphenyl ethers in Chinese pregnant women.

Background: Polybrominated diphenyl ethers (PBDEs) are a group of widely used chemicals and humans are exposed to them in their daily life. PBDEs exposure during pregnancy may have adverse effects on pregnant women and their fetuses. Nevertheless, limited information is available on the levels and determinants of PBDEs exposure in Chinese pregnant women.

Methods: The internal exposure levels of eight PBDEs (BDE-28, 47, 99, 100, 153, 154, 183, and 209) in placental samples of 1280 pregnant women from Zunyi birth cohort were analyzed using gas chromatography tandem mass spectrometry. All PBDEs concentrations were lipid adjusted (ng/g lw). Determinants of exposure were assessed by multivariable logistic regression model.

Results: Eight PBDE homologues were quantifiable in more than 70% of the samples. The highest median concentrations were found for BDE-209 (2.78 ng/g lw), followed by BDE-153 (1.00 ng/g lw) and BDE-183 (0.93 ng/g lw). The level of ΣPBDEs ranged from 0.90 to 308.78 ng/g lw, with a median concentration of 10.02 ng/g lw. Multivariate logistic regression analysis showed that maternal age older than 30 years old (OR: 1.59; 95% CI: 1.14, 2.23), pre-pregnancy obesity (1.51; 1.08, 2.10), home renovation within 2 years (1.43; 1.08, 1.91), spending more time outdoors during pregnancy (0.70; 0.55, 0.89), high consumption of fish/seafood (1.46; 1.13, 1.90) and eggs (1.44; 1.04, 2.00), male infant sex (1.69; 1.18, 2.42) were associated with PBDEs exposure.

Conclusion: The study population is generally exposed to PBDEs, of which BDE-209 is the dominant congener, indicating extensive application of products containing deca-BDE mixtures. Maternal age, pre-pregnancy BMI, home decoration, average outdoor time during pregnancy, fish, seafood, eggs consumption, and fetal sex were exposure-determinning factors. This study contributes to the knowledge on region-specific PBDEs contamination in pregnant women and related risk factors.