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

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

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。

Hexabromocyclododecanes（ HBCDs） are globally produced brominated flame retardant（ BFR） and are used primarily as an additive FR in thermal insulation building materials,upholstery textiles,and electronics.HBCDs not only pollute the ecological environment,but also harm the health of human beings through the food chain. The study on the environmental fate and biomagnification of HBCDs diastereomers and enantiomers in food chains is an important foundation for risk assessment and effective pollution control. The characteristics of HBCDs, the selective accumulation,biomagnification and transformation of HBCDs diastereomers and their enantiomers in food chain are reviewed in this paper. The influence factors of the selective accumulation and transformation were most likely ascribed to the combined effect of several aspects,including the living and feeding habits,trophic level of organisms,and the selective absorption, metabolism and bioisomerization of HBCDs. Recent research results indicate that the accumulation,transformation and biomagnifications behavior of HBCDs diastereomers and their enantiomers in the ecological system is not a single process,but the result of multiple factors of biological and environmental processes. Further studies will focus on the selective environmental behavior of HBCDs diastereomers and enantiomers in the freshwater and terrestrial food chains and the control influence factors of the selective environmental behavior during food chains transfer,which will provide a scientific basis for the assessment of environmental risks.