Placental Transfer of Dechlorane Plus in Mother–Infant Pairs in an E-Waste Recycling Area (Wenling, China)

Abstract

It has been reported that breastfeeding can expose newborns to dechlorane plus (DP), but transplacental transfer of DP has not been documented. We measured DP and its dechlorinated analogs in matched maternal blood− placenta−cord blood samples from 72 residents of the e-waste recycling area of Wenling, China. DP was detected in cord sera, indicating the occurrence of prenatal DP exposure and the transfer of DP across the placenta. The concentration ratio in the cord serum and maternal serum was estimated to be 0.45 for syn-DP and 0.35 for anti-DP, indicating the placenta partially limited DP transfer with a greater extent for anti-DP. The DP concentrations in the maternal serum, placenta, and cord serum strongly correlated, indicating that DP could transfer between the tissues. The DP concentrations in the matched samples could be predicted from each other. The anti-DP/ total DP concentration ratios in the placentas and cord sera were significantly different from those in the maternal sera, suggesting that DP stereoselectively bioaccumulates in human tissues. When the congener concentrations of polybrominated diphenyl ethers (PBDEs) were used as control variables, DP and total triiodothyronine concentrations were associated in the sera from mothers who had lived in Wenling for over 20 years.

Current Levels and Composition Profiles of Emerging Halogenated Flame Retardants and Dehalogenated Products in Sewage Sludge from Municipal Wastewater Treatment Plants in China

“…This is consistent with the recent reports in wildlife 58,59 and human beings. 60 The concentrations of Cl 11 -DP were in the range of nd−4.15 ng g −1 with an average of 0.18 ng g −1 , which were apparently higher than those in coastal sediments (nd−0.04 ng g −1 ) in north China. 61 A significant correlation was also found between the concentrations of Cl 11 -DP and DP in sewage sludge (R = 0.921, p < 0.01).…”

Cumulative Chemical Exposures During Pregnancy and Early Development

“…PBDEs are also frequently detected in breast milk [65, 73]. RFRs have also been measured in maternal serum and breast milk [67, 74–76], and RFR metabolites are measurable in maternal urine [77]. Flame retardants are able to cross the placenta throughout pregnancy [72, 78], though maternal levels do not decrease [77, 78].…”

“…PBDEs have been measured in cord serum [71, 73], placenta [72, 79], amniotic fluid [80], and colostrum [81]. RFRs have been measured in cord serum and the placenta [76]. PBDE metabolites (OH-PBDEs) are also found, at much lower levels, in both maternal and fetal matrices [55, 64, 70, 82].…”

“…However, others, such as BDE-47 and -28, show a less consistent pattern [70, 71, 73, 74, 81]. Similarly, some RFRs are higher in maternal serum, but others are higher in cord serum [74, 76]. Several studies suggest that highly brominated PBDEs cross the placenta more readily than lower brominated PBDEs [73, 84], but one systematic review did not support that pattern [3].…”

Levels of Non-PBDE Halogenated Fire Retardants and Brominated Dioxins and their Toxicological Effects in Indoor Environments - A Review

“…There was a previous study that reported an association between thyroid hormone levels and DP concentrations in serum in mother-infant pairs near an e-waste recycling area in China (Ben et al, 2014), but its endocrine disruption potential was not investigated. A study by Kang et al (2016) examined oral and water-borne exposure pathways of DP to zebrafish, and toxicological responses, including oxidative stress and endocrine disruption, were evaluated.…”