Guangdong Provincial Institute of Public Health, Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China.
Guangdong Provincial Center for Disease Control and Prevention, Guangzhou 511430, China.
Sci Total Environ. 2020 Nov 10;742:140597. doi: 10.1016/j.scitotenv.2020.140597. Epub 2020 Jun 30.
Polychlorinated biphenyls (PCBs) and halogen flame retardants (HFRs) are major pollutants in e-waste recycling area. High internal exposure levels of PCBs and HFRs are harmful to human thyroid hormone (TH) equilibrium. To examine their disrupting effects on TH, we conducted a study on children (n = 114) of an e-waste recycling and a control area in South China. Concentrations of PCBs, HFRs, and TH levels were determined in serum samples. TH related proteins and their corresponding gene were also monitored as markers of such disruption. Levels of these chemicals in the exposed group were much greater than those in the control group. Results of the linear regression and generalized additive model indicated the presence of close relationships between the internal exposure levels and the responses of TH related proteins, gene expression. More extensive exposure concentrations of these chemicals led to higher expression of iodothyronine deiodinase I and decreased the concentrations of thyroid-stimulating hormone, expression of TH receptor α, indicating the exertion of discrepant and even contrary influences on equilibrium of TH, and a compensation of these mechanisms may kept the homeostasis of TH. These results for children warrant further investigation on the health risks of PCBs and HFRs exposure in e-waste area.
多氯联苯（PCBs）和卤代阻燃剂（HFRs）是电子废物回收领域的主要污染物。PCBs 和 HFRs 的高内暴露水平对人体甲状腺激素（TH）平衡有害。为了研究它们对 TH 的干扰作用，我们对中国南方一个电子废物回收区和一个对照区的儿童（n=114）进行了一项研究。在血清样本中测定了 PCBs、HFRs 和 TH 水平。还监测了 TH 相关蛋白及其相应基因，作为这种干扰的标志物。暴露组这些化学物质的水平明显高于对照组。线性回归和广义加性模型的结果表明，内暴露水平与 TH 相关蛋白、基因表达的反应之间存在密切关系。这些化学物质更广泛的暴露浓度导致甲状腺素脱碘酶 I 的表达增加，促甲状腺激素浓度降低，TH 受体 α 的表达减少，表明对 TH 平衡产生了不同甚至相反的影响，这些机制的补偿可能维持了 TH 的内稳态。这些结果表明，需要进一步研究儿童在电子废物区接触 PCBs 和 HFRs 的健康风险。
