手性污染物六溴环十二烷在食物链传递中的选择性及生物放大作用研究进展

六溴环十二烷(HBCDs)是一种全球生产的添加型溴化阻燃剂,被广泛应用于隔热建筑材料阻燃剂、室内装潢、纺织品和电子产品中,不仅对生态环境造成污染,而且还会通过食物链的传递危害人类健康。研究生态系统中HBCDs异构体及对映体的环境行为与生物放大作用是进行环境风险评估和有效控制污染的生态学基础。基于此,本文从HBCDs的基本特性出发,阐述了HBCDs异构体及对映体在食物链中的选择性生物富集放大及转化行为,分析了发生选择性富集及转化的影响因素,这些因素包括生物体的生活环境、饮食习惯、所处食物链中营养级水平以及HBCDs选择性吸收、代谢和异构化等。已有的研究报道显示HBCDs异构体及对映体在生态系统中的富集、转化及生物放大行为不是单一的过程,是生物体和环境多因素综合的结果。今后应对HBCDs异构体及对映体在各种食物链(如淡水食物链和陆生食物链)中的选择性环境行为以及在食物链传递中发生选择性的主控因素等方面进行深入系统的研究,为全面评价其生态风险提供科学依据。

Research Progress on the Selectivity and Biomagnification of Chiral Hexabromocyclododecanes Pollutants in Food Chain Transfer

The safe disposal of radioactive waste, especially high level radioactive liquid, is very important. It is generally believed that, the safest and feasible way to deal with the waste liquid is solidify it and store in a suitable geological layer. Glass solidification is one of the commonly used methods to cure high radio waste liquid. It has the advantages of high resistance to chemical corrosion resistance, good radiation stability, thermal stability and mechanical stability, but the lack of resistance to water leaching and other properties has declined to make its safety need to be further evaluated by the anti leaching experiments. In order to measure the ability of resistance to leaching with glass solidified samples, SIMS is used to analyzed composition distribution and leaching behavior of the radioactive elements in the solidified samples. It is an effective method for the analysis of the properties of glass solidification. In this paper SIMS analysis method of glass solidified samples was studied. With the method of vacuum evaporation carbon, the problem of poor conductivity of the glass solidified samples was effectively solved. The test of the uranium component in the simulated glass solidified sample was completed. The results show that, the new method is suitable for the measurement of the distribution of uranium in glass samples. The test results of the ²³⁵U/²³⁸U is about 7.9, which is consistent with the isotopic characteristics of the uranium components of the simulated samples. It is proved that improving the conductivity of solidified glass by coating carbon and then analyzing the element distribution and isotopic abundance with SIMS is feasible.