Center for Marine Environmental Studies, Ehime University, Bunkyo-cho 2-5, Matsuyama, 790-8577, Japan.
Arch Environ Contam Toxicol. 2014 Jul;67(1):29-41. doi: 10.1007/s00244-014-0021-y. Epub 2014 Apr 10.
Perchlorate (ClO4 (-)) and thiocyanate (SCN(-)) interfere with iodide (I(-)) uptake by the sodium/iodide symporter, and thereby these anions may affect the production of thyroid hormones (THs) in the thyroid gland. Although human exposure to perchlorate and thiocyanate has been studied in the United States and Europe, few investigations have been performed in Asian countries. In this study, we determined concentrations of perchlorate, thiocyanate, and iodide in 131 serum samples collected from 2 locations in Northern Vietnam, Bui Dau (BD; electrical and electronic waste [e-waste] recycling site) and Doung Quang (DQ; rural site) and examined the association between serum levels of these anions with levels of THs. The median concentrations of perchlorate, thiocyanate, and iodide detected in the serum of Vietnamese subjects were 0.104, 2020, and 3.11 ng mL(-1), respectively. Perchlorate levels were significantly greater in serum of the BD population (median 0.116 ng mL(-1)) than those in the DQ population (median 0.086 ng mL(-1)), which indicated greater exposure from e-waste recycling operations by the former. Serum concentrations of thiocyanate were not significantly different between the BD and DQ populations, but increased levels of this anion were observed among smokers. Iodide was a significant positive predictor of serum levels of FT3 and TT3 and a significant negative predictor of thyroid-stimulating hormone in males. When the association between serum levels of perchlorate or thiocyanate and THs was assessed using a stepwise multiple linear regression model, no significant correlations were found. In addition to greater concentrations of perchlorate detected in the e-waste recycling population, however, given that lower concentrations of iodide were observed in the serum of Vietnamese females, detailed risk assessments on TH homeostasis for females inhabiting e-waste recycling sites, especially for pregnant women and their neonates, are required.
高氯酸盐（ClO4 (-)）和硫氰酸盐（SCN (-)）会干扰钠/碘转运体对碘化物（I (-)）的摄取，因此这些阴离子可能会影响甲状腺中甲状腺激素（THs）的产生。尽管在美国和欧洲已经研究了人类接触高氯酸盐和硫氰酸盐的情况，但在亚洲国家进行的调查很少。在这项研究中，我们测定了来自越南北部两个地点（Bui Dau [BD]；电子和电气废物[电子废物]回收场和 Doung Quang [DQ]；农村地区）的 131 份血清样本中的高氯酸盐、硫氰酸盐和碘化物浓度，并检查了这些阴离子血清水平与 THs 水平之间的关系。越南受试者血清中检测到的高氯酸盐、硫氰酸盐和碘化物的中位数浓度分别为 0.104、2020 和 3.11ng/mL。BD 人群血清中的高氯酸盐水平明显高于 DQ 人群（中位数 0.116ng/mL），这表明前者的电子废物回收作业造成的接触程度更大。BD 和 DQ 人群的血清硫氰酸盐浓度没有显著差异，但吸烟人群的这种阴离子水平升高。碘化物是 FT3 和 TT3 血清水平的显著正预测因子，也是男性促甲状腺激素的显著负预测因子。当使用逐步多元线性回归模型评估高氯酸盐或硫氰酸盐与 TH 之间的关联时，未发现显著相关性。然而，除了在电子废物回收人群中检测到更高浓度的高氯酸盐外，由于越南女性血清中碘化物浓度较低，因此需要对居住在电子废物回收场的女性，尤其是孕妇及其新生儿的 TH 动态平衡进行详细的风险评估。
