环境内分泌干扰物质的健康影响与作用机制

本文综述了环境内分泌干扰物质与人或动物生殖发育、行为智力、免疫功能、肥胖、糖尿病、癌症等异常或疾病的相关性及相关作用机制,讨论了其"低剂量效应"和"复合效应",对本领域今后发展的方向进行了探讨.     

Removal of estrogens by electrochemical oxidation process

Treatments of estrogens such as Estrone(E1), Estradiol(E2) and Ethinylestradiol(EE2) were conducted using an electrolytic reactor equipped with multi-packed granular glassy carbon electrodes.Experimental results showed that E1, E2 and EE2 were oxidized in the range of 0.45–0.85 V and were removed through electro-polymerization. Observed data from continuous experiments were in good agreement with calculated results by a mathematical model constructed based on mass transfer limitation. In continuous treatment of trace estrogens(1 μg/L), 98% of E1, E2 and EE2 were stably removed. At high loading rate(100 μg/L), removal efficiency of E1 was kept around 74%–88% for21 days, but removal efficiency reduced due to passivation of electrodes. However, removal efficiency was recovered after electrochemical regeneration of electrodes in presence of ozone. Electric energy consumption was observed in the range of 1–2 Wh/m3. From these results, we concluded that the present electrochemical process would be an alternative removal of estrogens.     

松花江水体和底泥中的环境激素类等物质的监测研究

通过对不同萃取与净化方法的比较选择,建立了一个同时检测环境介质中(水、沉积物)五种激素类物质与六种本分美内分泌干扰物的气相色谱-质谱联用分析方法,回收率在70%以上,应用此方法对松花江哈尔滨段江水样品和沉积物样品进行分析,结果酚类内分泌干扰物的浓度均远低于世界其他国家和地区,天然和人工合成激素类物质和其他国家和地区浓度相当或略高。     

炔雌醇和壬基酚在土壤中的吸附-解吸特征

通过吸附动力学研究和批量平衡试验,以炔雌醇(EE2)和壬基酚(NP)为代表,考察内分泌干扰物在3种不同性质的天然土壤中的吸附-解吸特征.结果表明,双室一级动力学模型比单室一级动力学模型更适合描述EE2、NP在土壤中的动态吸附过程.快吸附过程在吸附初期占据主导地位,之后慢吸附室的相对贡献逐渐增大,直至达到吸附平衡.土壤对NP的吸附速率是EE2的2.0～4.7倍.Freundlich模型和DA模型均能较好地拟合EE2与NP的吸附等温线,但DA模型拟合效果更佳.饱和吸附容量与土壤有机质含量呈显著正相关,EE2的饱和吸附容量(0.85～7.67μg·g-1)明显低于NP(10.47～110.15μg·g-1).吸附自由能计算表明,土壤对EE2和NP的吸附以物理作用为主.此外,3种受试土壤对EE2和NP的解吸附均存在滞后现象,需要预防其潜在的环境风险,其中有机质含量最高、比表面积最大的土样滞后性最明显.     

饮用水水源及水厂内分泌干扰物污染分析

对国内的饮用水水源地内分泌干扰物污染现状进行总结,发现我国饮用水水源地很多地区都存在着内分泌干扰物的污染,由于地域的不同,污染物的种类存在差异,但有机氯农药和多氯联苯类化合物的污染尤为严重。同时对水源地内分泌干扰物的种类、来源及生物学效应进行综述,并对内分泌干扰物的毒性作用机制进行了归纳,发现不同来源的内分泌干扰物,毒性作用机制不同,且一种内分泌干扰物可能同时存在多种作用机制。     

蛋白质组学技术在环境内分泌干扰物分析上应用

为了探讨蛋白质组学技术在环境雌激素分析上的应用,用浓度为3.7×10-9mol/L的17β-雌二醇(E2)处理MCF-7细胞2或3天后进行双向电泳,对比不同的蛋白质提取、染色方法,利用光密度扫描仪将电泳图像数字化,并使用PDQuest软件进行图像分析,以观察雌激素诱导下的蛋白质表达图谱。结果表明,在蛋白质的提取上,冻融法比超声裂解法更有效;在蛋白质染色上,银染法比考马斯亮蓝染色法能得到更多可显示的蛋白质斑点。用E2处理72h后的MCF-7细胞,可检测到40个下调蛋白和5个上调蛋白。该蛋白质表达模式的改变提示了环境雌激素诱导下的特异性蛋白质表达图谱变化。本研究为分析雌激素类内分泌干扰物的内在作用机制提供了一种新的可行方法,也为建立其高通量筛选方法提供了新的思路。     

DEHP、DBP内分泌干扰活性的实验研究

利用MCF-7细胞增殖实验、细胞周期分析、细胞雌激素受体水平测定和断乳大鼠子宫增重实验探讨了邻苯二甲酸二乙基己酯(DEHP)和邻苯二甲酸二丁酯(DBP)内分泌干扰活性及其可能的作用机制.结果表明,DEHP和DBP可诱导MCF-7细胞增殖、细胞内雌激素受体水平增高,对细胞周期无明显影响,DEHP不引起断乳大鼠子宫增重.推断DEHP和DBP可能并不是通过模拟雌激素而是引起体内天然激素受体水平改变等其他机制影响机体内分泌系统.     

Endocrine disrupting effects on Chinese rare minnow (Gobiocypris rarus) fed with field collected Limnodrilus sp

The potential endocrine disrupting effects and other toxicity effects on aquatic biota resulted from food uptake was simulated by feeding the laboratory cultured rare minnow ( Gobiocypns rams) with field collected Limnodnlus sp. The results indicated that the food chain processes affected significantly the growth, slightly reduced gonadosomatic indices, and elevated hepatosomatic indices. There was an obvious vitellogenin(VTG) induction, which generally only occurred in mature female, in the serum of juvenile rare minnow and mature male when fed with Limnodrilus sp. In addition, the rare minnow feeding on Limnodnlus sp. had significantly high renal indices, it meant obvious renal hyperplasia. The present work suggested that Limnodnlus sp. from field water may contain toxic pollutants and could lead to endocrine disruption effects to the predators. It was concluded that endocrine disruptors may not only be assimilated through water, but also be bioconcentrated through food web. The results also suggested the importance of food selection in conducting the study of endocrine disruption effects using sensitive species.     

污染物对鱼类的甲状腺激素干扰效应及其作用机制

环境中可以影响生物体甲状腺激素合成、运输、作用和代谢等过程的化学污染物称为甲状腺激素干扰物(TDCs),TDCs被认为是继环境雌激素之后最重要的一类内分泌干扰物.鱼类甲状腺的结构、甲状腺激素的转运和功能等与哺乳动物有较大差别.与哺乳动物相比,污染物干扰鱼类甲状腺激素的研究还较为缺乏.在介绍鱼类甲状腺结构、功能以及甲状腺激素在鱼体内动态过程的基础上,分析了污染物对鱼类的甲状腺激素干扰效应及其作用机制,探讨了今后鱼类甲状腺激素干扰研究的主要方向.污染物能对鱼类甲状腺激素水平、相关酶活性及甲状腺结构等产生直接影响;同时,污染物还可以通过干扰鱼类甲状腺系统对由甲状腺激素调节的重要生理过程如生长、繁殖和发育等产生间接影响.污染物主要通过干扰鱼类甲状腺激素的合成与分泌、转运、清除以及与甲状腺激素受体(TR)的相互作用等机制对鱼类产生不利影响.在污染物对鱼类甲状腺激素干扰的研究中,今后应重点关注环境中"新型"卤化有机污染物、鱼类早期发育过程与甲状腺激素干扰效应的关系、TR介导机制以及TDCs的筛选方法等.     

丰水期沱江水系环境内分泌干扰物分布特征

采集丰水期沱江水系德阳至泸州水样,分析6种环境内分泌干扰物的含量和分布特征。主要检出双酚A、壬基酚,双酚A的平均浓度为3.93~198 ng/L,与国内外河流浓度相比处于中等水平;壬基酚平均浓度为5.23~150 ng/L,与国外河流水平相当,但低于目前已有报道的国内河流。沱江水系中双酚A、壬基酚的分布整体均呈现出北高南低,上游高于中游、下游,干流低于支流的特征。