Distribution and Pattern Profiles of Chlorinated Paraffins in Human Placenta of Henan Province, China

Due to the high production volume, wide industrial applications, and environmental persistence, chlorinated paraffins (CPs) have been observed in various environmental matrices. However, data are scarce regarding human exposure to CPs. In this study, 54 human placentas were collected and analyzed by gas chromatography quadrupole time-of-flight mass spectrometry (GC-QTOF-HRMS). Short-chain CPs (SCCPs) were detected in all samples, with the concentrations ranging from 98.5 to 3771 ng/g lw (lipid weight). Medium-chain CPs (MCCPs) were detected in 38 of the samples, with the concentrations being in the range from 80.8 to 954 ng/g lw. SCCPs with 6-7 chlorines were predominant in human placentas and were mostly within the 10-11 carbon chain groups. In most samples, C15H25Cl7 were found to be the most abundant MCCP congener groups. Pearson correlation analysis indicated that there was a significant positive correlation between the Sigma SCCPs and Sigma MCCPs concentrations in the placenta samples, whereas the concentrations of the Sigma SCCPs/Sigma MCCPs had no significant correlations with the gravida's age, weight, or the lipid contents of placenta. To the best of our knowledge, this report describes the first investigation of CPs in the human placenta, which provides data for future evaluation of human exposure to CPs.