Umbilical cord serum PBDE concentrations and child adiposity measures at 7 years

Background: Polybrominated diphenyl ethers (PBDEs) exist extensively in the environment. Toxicological studies suggested PBDEs may interfere with adipogenic pathways. However, few human evidence addressed PBDE exposures in utero related to childhood adiposity. Objective: We assessed associations between PBDEs concentrations in cord serum and childhood adiposity measures at 7 years. Methods: Among 318 mother-child pairs from Sheyang Mini Birth Cohort Study (SMBCS) in China, nine PBDE congener concentrations were quantified in umbilical cord serum using gas chromatography-negative chemical ionization mass spectrometry (GC-NCI-MS). Anthropometric indicators of children aged 7 years were measured, including weight, height and waist circumference. Age and sex-specific body mass index (BMI) z scores were calculated based on World Health Organization (WHO)'s child growth standards. Multivariate linear and logistic regression models adjusted for putative confounders were performed to examine associations between PBDE congeners and adiposity parameters. Results: BDE-209 was the most abundant congener of PBDEs with a median value of 19.5 ng/g lipid. The geometric mean values of nine PBDE congeners ranged from below limit of detection (LOD) to 18.1 ng/g lipid, and the detection rates were 46.5%similar to 96.5%. Cord serum BDE-153 and BDE-154 concentrations were associated with lower childhood BMI z score (regression coefficient, beta=-0.15, 95% confidence interval:-0.29,-0.02; p=0.02; beta=-0.23, 95%CI:-0.43,-0.03; p=0.03, respectively) and lower waist circumference (beta=-0.75 cm, 95%CI:-1.43,-0.06; p=0.03; beta=-1.22 cm, 95%CI:-2.23,-0.21; p=0.02, respectively), after controlling for potential confounders. Moreover, prenatal BDE-154 exposure was related to a decreased obesity risk of children aged 7 years (odds ratio, OR=0.46, 95%CI: 0.22, 0.94; p=0.03). These effects were only observed among boys in sexstraitified analyses. Conclusions: Cord serum BDE-153 and BDE-154 concentrations were related to reduced adiposity measures at 7 years of age. Further evidence regarding the impacts of prenatal PBDE exposures on childhood development is warranted.