四溴乙基环己烷(TBECH)立体异构体的分析方法与环境行为及毒性效应研究进展

Analytical Methods, Environmental Behaviors and Toxicological Effects of 1,2-Dibromo-4-(1,2-dibromoethyl)-cyclohexane (TBECH) Stereoisomers

1,2-二溴-4-(1,2-二溴乙基)-环己烷,又名TBECH(tetrabromoethylcyclohexane,四溴乙基环己烷),是一种添加型的新型溴代阻燃剂.TBECH的立体结构复杂,具有4个异构体,每个异构体又均含有一对对映体.随着传统溴代阻燃剂的禁止生产或限制使用,TBECH作为替代品之一被广泛用于建筑业、纺织业和电子等各行业.TBECH具有长距离迁移性、生物累积性和潜在毒性,被认为是一种可能的持久性有机污染物.通过对TBECH立体异构体的分析方法、环境行为和毒性效应研究的最新进展进行综述发现,TBECH的检测通常采用气相色谱质谱联用法,但仅集中于对环境样品中TBECH非对映异构体的分离分析,对映体水平的检测将成为未来TBECH立体异构体分析的发展方向.TBECH已在大气、水体、沉积物、土壤等环境介质和生物体中被陆续检出,并对生物体产生内分泌干扰、生殖发育等毒性效应,其各立体异构体具有特异的环境行为,表现出选择性的生物累积、转化和毒性效应.鉴于目前TBECH环境行为的研究主要关注水生生态系统,而从立体异构体水平出发的研究还很欠缺,建议今后加强对陆生生态系统中TBECH污染状况、分布特征以及环境行为的研究,进一步从异构体和对映体水平深入探讨TBECH的环境过程和生物效应,全面认识环境中TBECH的迁移转化规律及最终归趋.

1,2-dibromo-4-(1,2-dibromoethyl)-cyclohexane,also known as tetrabromoethylcyclohexane(TBECH),is a novel additive brominated flame retardant(BFR).It has a complex stereochemistry and consists mainly of four diastereomers with each of them having a pair of enantiomers.With the ban on production or the restricted use of legacy BFRs,TBECH,as one of the substitutes,is widely used in construction,textile and electronics industries.Due to its long-range transport,bioaccumulation and potential toxicity,TBECH is considered as a possible persistent organic pollutant.The analytical methods,environmental behaviors and toxicological effects of TBECH are reviewed.TBECH is usually detected by gas chromatography-mass spectrometry(GC-MS),but it only focused on the separation and analysis of TBECH diastereomers in the environmental samples.Detection of TBECH enantiomers will become the future development direction in the analysis of TBECH stereoisomers.TBECH has been successfully detected in various environmental media such as air,water,sediment and soil,and as well as in organisms.In addition,TBECH can cause endocrine-disrupting,reproductive and developmental toxicities and other toxic effects on organisms.The environmental behaviors of TBECH are stereoisomer-specific,and bioaccumulation,transformation and toxicological effects of TBECH are selective.So far,studies on environmental behaviors of TBECH are mainly focused on the aquatic ecosystem,which is still insufficient at the stereoisomer level.Therefore,the environmental processes and biological effects of TBECH should be further studied at the diastereomer and enantiomer levels in the future.Moreover,to fully understand the migration and transformation of TBECH and their environmental fate,more attention should be paid to the occurrence,distribution and environmental behavior of TBECH in the terrestrial ecosystem.