Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China.
Ministry of Education Key Laboratory of Integrated Regulation and Resource Development on Shallow Lakes, Hohai University, Nanjing 210098, PR China; Yangtze Institute for Conservation and Development, Jiangsu, 210098, PR China.
Water Res. 2022 Jun 1;216:118324. doi: 10.1016/j.watres.2022.118324. Epub 2022 Mar 19.
Understanding the interactions between dissolved organic matter (DOM) and perfluoroalkyl acids (PFAAs) is essential for predicting the distribution, transport, and fate of PFAAs in aquatic environments. Based on field investigations in the northwest of Taihu Lake Basin combined with laboratory experiments, we obtained DOM and PFAA concentrations as well as compositions and investigated key factors of DOM affecting PFAA variability and capture of PFAAs by DOM. Results indicated that the total concentrations of PFAAs were 73.4-689 ng/L in surface water and that PFAAs were dominated by C3-7 perfluoroalkyl carboxylic acids and perfluorooctane sulfonic acid. The main components of DOM included tyrosine-, fulvic-, and tryptophan-like substances. The Mantel test revealed a significant positive correlation between DOM and PFAAs (P = 0.0001). Fulvic-like substances were identified as the most crucial factors affecting PFAA variability. The laboratory experiments revealed that DOM can spontaneously aggregate into a microgel. Furthermore, 19.1-50.9% of PFAAs, DOM characteristic peaks, and several metals (Ca, Mg, Cu, and Fe) can be removed during aggregation, indicating the capacity of DOM binding organic/inorganic substances. The fulvic-like substances were more effectively removed than the protein-like substances. The distribution coefficients of all PFAAs except perfluorohexanoic acid significantly correlated with their perfluorinated carbon numbers (r = 0.975, p<0.001). Our results provided insights into the interactions between DOM and PFAAs, improving the understanding of the distribution, transport, and fate of PFAAs in aquatic environments.
了解溶解有机质 (DOM) 和全氟烷基酸 (PFAAs) 之间的相互作用对于预测 PFAAs 在水生环境中的分布、迁移和归宿至关重要。本研究基于太湖流域西北部的野外调查和实验室实验，获得了 DOM 和 PFAA 浓度以及组成，并探讨了影响 DOM 中 PFAA 变异性和 PFAAs 捕获的关键因素。结果表明，地表水中 PFAAs 的总浓度为 73.4-689ng/L，且以 C3-7 全氟烷基羧酸和全氟辛烷磺酸为主。DOM 的主要成分包括酪氨酸、富里酸和色氨酸类物质。Mantel 检验表明 DOM 与 PFAAs 之间存在显著正相关 (P=0.0001)。富里酸类物质被确定为影响 PFAA 变异性的最关键因素。实验室实验表明，DOM 可以自发聚集形成微凝胶。此外，在聚集过程中可以去除 19.1-50.9%的 PFAAs、DOM 特征峰和几种金属（Ca、Mg、Cu 和 Fe），表明 DOM 具有结合有机/无机物质的能力。富里酸类物质比蛋白类物质更易被去除。除全氟己酸外，所有 PFAAs 的分布系数均与全氟碳原子数显著相关 (r=0.975，p<0.001)。本研究结果深入了解了 DOM 和 PFAAs 之间的相互作用，提高了对 PFAAs 在水生环境中分布、迁移和归宿的认识。
