扩散梯度薄膜探针原位分析全/多氟烷基物质在水-沉积物系统中的分布特征  

In Situ Analysis of Per-and Polyfluoroalkyl Substances Distribution Characteristics in Water-Sediment System Using Diffusive Gradients in Thin Films Probe

作　　者：蔡绮思 李星颖 张芳 杨君伟 刘思思 陈长二 CAI Qi-Si;LI Xing-Ying;ZHANG Fang;YANG Jun-Wei;LIU Si-Si;CHEN Chang-Er(Guangdong Provincial Key Laboratory of Chemical Pollution and Environmental Safety&MOE Key Laboratory of Theoretical Chemistry of Environment,School of Environment/Environmental Research Institute,South China Normal University,Guangzhou 510006,China)

机构地区：[1]华南师范大学环境研究院/环境学院,广东省化学污染与环境安全重点实验室,环境理论化学教育部重点实验室,广州510006

出　　处：《分析化学》2025年第2期300-310,共11页Chinese Journal of Analytical Chemistry

基　　金：国家自然科学基金项目(No.42277457);中国科学院海洋大科学中心重点部署项目(No.COMS2019J08)资助。

摘　　要：水-沉积物界面是化学物质迁移转化的重要场所,而传统采样方法不易进行原位采样,因此,对于微观界面中环境化学过程信息的捕捉十分困难。本研究利用扩散梯度薄膜(DGT)探针技术原位探测水-沉积物系统中18种全/多氟烷基物质(PFAS),以阐明其垂直分布的特征和规律。结果表明,不同类型的PFAS在水和沉积物中随深度的变化呈现明显不同的规律,其中,短链PFAS迁移性较大,长链PFAS因其较强的疏水性和吸附能力,在沉积物及孔隙水中的迁移受限,在沉积物柱中浓度变化较小。采用DGT探针测得PFAS浓度范围为11.2~1305μg/L,长链PFAS测定结果高于直接测定的水样和孔隙水,而短链PFAS则相反。采用DGT测定的结果表明,虽然长链PFAS在沉积物颗粒上的吸附较强,但吸附的PFAS仍具有较大的可利用性。DGT探针技术具有原位和高空间分辨率的优势,可用于深入理解微界面环境中发生的复杂环境过程,为评估污染物的吸附解吸行为、有效性和生态风险提供了重要技术支撑和科学依据。The water-sediment interface is an important zone for the migration and transformation of chemical substances,but traditional sampling methods make in situ sampling challenging,thus it is difficult to capture information on environmental processes at the micro-scale.In this study,diffusive gradients in thin films(DGT)probe technique was used as in situ tool to detect 18 kinds of typical per-and polyfluoroalkyl substances(PFAS)in the water-sediment system,elucidating their vertical distribution characteristics and patterns.The results showed that different PFAS exhibited distinct variation patterns with depth in water and sediment.Short-chain PFAS exhibited greater mobility,while the migration of long-chain PFAS was restricted in sediment and pore water due to their strong hydrophobicity and adsorption capacity,resulting in relatively small concentration changes in the sediment column.The PFAS concentrations measured by DGT ranged from 11.2μg/L to 1305μg/L.For longchain PFAS,the concentrations measured by DGT were higher than those obtained from direct measurement of water and pore water,while the opposite results were obtained for short-chain PFAS.The DGT results indicated that although long-chain PFAS exhibited strong adsorption to sediment particles,the adsorbed PFAS were still bioavailable.DGT probe technique,with its advantages of in situ sampling and high spatial resolution,provides deep insights into the complex environmental processes occurring at the microscale in the water-sediment systems.DGT offers important technical support and scientific evidence for assessing the adsorption-desorption behavior,bioavailability,and ecological risks of these emerging pollutants in aquatic environment.

关 键 词：全/多氟烷基物质 被动采样技术 水环境 沉积物 界面环境行为 

分 类 号：X70[环境科学与工程—环境工程]