Elevated Body Burdens of PBDEs, Dioxins, and PCBs on Thyroid Hormone Homeostasis at an Electronic Waste Recycling Site in China

Abstract

A cross-sectional study of 25 sample sets (each set consisted of maternal serum and cord whole blood) from 50 pregnant women in zone A (n = 25 from exposed group) and zone B (n = 25 from reference group) was conducted to examine the association between thyroid hormone (TH) levels and PBDE, PCDD/F, and PCB exposures. Thyroid hormones TT3, TT4, and TSH levels were measured in maternal serum at 16 weeks of gestation. The concentrations of PBDEs, PCDD/Fs, and PCBs were determined by isotope dilution HRGC/HRMS in cord blood samples. Body burdens of the three contaminants in cord blood in zone A (median: summation sigma TEQ-PCDD/Fs 0.041, summation operator TEQ-PCBs 0.022 pg WHO-TEQ/g, summation operator PBDEs 23.4 pg/g whole weight, respectively) were significantly higher than those from the reference area (median: summation sigma TEQ-PCDD/Fs 0.014, summation sigma TEQ-PCBs 0.0041 pg WHO-TEQ/g, summation sigma PBDEs 16.15 pg/g, respectively) (p < 0.05). Levels of TT4 and TSH in serum in zone A were significantly lower than those in zone B (p < 0.05). A negative correlation was found between TT4 levels and body burdens of PCDD/Fs and PCBs. However, there was no significant association of concentration of PBDEs and levels of the three thyroid hormones. Our results suggest that electronic waste (e-waste) recycling contributes to high body burdens of PBDEs, PCDD/Fs, and PCBs and affects thyroid hormone homeostasis in humans. The potential health risk for neonates still needs further investigation.

Impact of Brominated POPs on the Neurodevelopment and Thyroid Hormones of Young Children in an Indoor Environment—A Review

“…Similar to the findings of our previous study (Lin et al, 2011), in a cohort study of infants born in the US indicates negative associations between cord blood levels of BDE-100 and BDE-153 and cord blood values of total T4 and FT3 (Herbstman et al, 2008). In contrast, several human studies that assess the associations between PBDEs and thyroid hormones in cord blood find no significant relation ( Mazdai et al, 2003;Kim et al, 2009;Zhang et al, 2010;Chevrier et al, 2011;Gascon et al, 2011;Kim et al, 2011). Specifically, Kim et al (2009) finds no apparent relationship between fetal T4 and cordblood PBDEs in 108 Korean infants.…”

“…Contrary to the above findings, a Dutch study finds that cord blood T3 level have significantly positive correlation with maternal serum levels of BDE-47, BDE-99, and BDE-100 in the 35th week of pregnancy (Roze et al, 2009). Most current epidemiological studies, including our previous study, have not found any relationship between prenatal exposure to PBDEs and cord blood TSH level (Herbstman et al, 2008;Kim et al, 2009;Roze et al, 2009;Zhang et al, 2010;Chevrier et al, 2011;Lin et al, 2011).…”

“…Specifically, Kim et al (2009) finds no apparent relationship between fetal T4 and cordblood PBDEs in 108 Korean infants. Zhang et al (2010) discovers non-significant correlations between PBDEs and levels of total T3 (TT3), TT4, and TSH in 50 cord blood samples from Chinese infants near an electronic waste recycling site in southeast China. Mazdai et al (2003) finds no apparent correlations between ΣPBDEs and TT4 and FT4 in 12 sample pairs of maternal and cord blood taken from subjects in the United States.…”

“…Many epidemiological studies that evaluate associations of PBDEs exposure and thyroid hormones in adults and newborns have been published previously, but their results are not consistent (Hagmar et al, 2001;Mazdai et al, 2003;Herbstman et al, 2008;Turyk et al, 2008;Dallaire et al, 2009;Kim et al, 2009;Roze et al, 2009;Chevrier et al, 2010;Zhang et al, 2010;Chevrier et al, 2011;Eggesbø et al, 2011;Gascon et al, 2011;Lin et al, 2011). A few studies report the negative impact of cord blood PBDEs on levels of human thyroid hormones after in utero exposure (Herbstman et al, 2008;Lin et al, 2011), but most studies conducted in humans have found no correlations.…”

Effects of EDDS and plant-growth-promoting bacteria on plant uptake of trace metals and PCBs from e-waste–contaminated soil

“…Abundant toxins, such as trace metals, polybrominated diphenyl ethers (PBDEs), and PCBs have been released into the environment due to use of primitive e-waste recycling processes [1][2][3][4][5][6][7][8]. High levels of persistent organic pollutants (POPs) and trace metals have been detected in the air, dust, soil, sediment, and biota samples around e-waste recycling sites, which may pose a threat to local residents and the ecosystem [9][10][11][12].…”