全氟化合物同分异构体的环境行为及毒性效应研究进展

以全氟辛烷磺酸盐(PFOS)和全氟辛烷羧酸(PFOA)为代表的全氟化合物(PFASs)是一类新型持久性有机污染物,目前已经在全球自然环境、野生生物及人群中广泛检出,其环境与健康问题已引起人们的高度重视。传统的电氟化法生产工艺使PFASs产品存在碳链同分异构体。这些PFAS的同分异构体可能具有不同的环境行为和毒理效应。随着分析方法的逐渐成熟,目前,国外的学者已经在该研究领域进行了一些探索性的研究,并取得了一定的进展,而我国在该领域的研究相对较少。以PFOS和PFOA为例,在介绍了PFAS同分异构体的来源、命名和世界各地生产厂家的异构体组成等基本信息的基础上,还系统介绍了环境介质中PFAS同分异构体的分析方法、环境迁移转化差异及源分析研究;生物和人体的生物累积性及毒理学差异等;并对目前存在的问题进行了讨论,为今后PFAS同分异构体的环境问题研究提供相应的参考。

Advances in Studies on Environmental Behaviors and Toxic Effects of Perfluoroalkyl Substances Isomers

Perfluoroalkyl substances (PFASs) are a new class of persistent organic pollutants. They widely present in the environment, wildlives and humans all over the world. Perfluorooctane sulfonate (PFOS) and perfluorooctanoic acid (PFOA) are the most popular PFASs. The traditional electro-chemical fluorination method leads to a complex mixture of linear and branched isomers in the final products of PFASs, i.e. the isomerization of the carbon chain. The linear and branched isomers may behave differently in the environment and display different toxicity to the biota. Due to the progress in analytical techniques, some foreign scholars initiated the study on the isomers of PFAS isomers and got some interesting results. However, the related research in our country is sparse. In this paper, taking PFOS and PFOA as example, some basic information, including the manufacturing sources, nomenclature and structure of the PFAS isomers, was introduced. Then, we systematically reviewed the research advances in the isomer analytical technologies, the differences in environmental behaviors of PFAS isomers and the application of source apportionment, and difference in bioaccumulation and toxicity for biota (including humans). At last, we discussed the current problems. This paper aimed to provide some useful information for further studies on PFAS isomers in the environment in future.