Mao Ruoyu, Lu Yonglong, Zhang Meng, Wang Cong, Sun Bin, Shi Yajuan, Song Shuai, Wang Pei, Yuan Jingjing, Zhao Jixin
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; University of Chinese Academy of Sciences, Beijing 100049, China.
State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences, Beijing 100085, China; State Key Laboratory of Marine Environmental Science and Key Laboratory of the Ministry of Education for Coastal Wetland Ecosystems, College of the Environment and Ecology, Xiamen University, Fujian 361102, China; University of Chinese Academy of Sciences, Beijing 100049, China.
Sci Total Environ. 2023 Feb 1;858(Pt 1):159693. doi: 10.1016/j.scitotenv.2022.159693. Epub 2022 Oct 24.
Frequent exchange of surface water and groundwater occurs in arid/semi-arid areas due to high evaporation and intensive irrigation activities, affecting the migration and transformation of per- and polyfluoroalkyl substances (PFASs) and threatening drinking water safety. This study analyzed legacy PFASs and potential precursors in surface water, groundwater, soil, and aquifer solid samples collected from a typical arid area, the Hetao Irrigation District of Northern China, to explore PFASs distribution and transformation between surface and ground. Total PFASs (ΣPFASs) in surface water was 29-232 ng/L, higher than 2-77 ng/L in groundwater. ΣPFASs in soil were 0.29-0.59 ng/g, higher than 0.09-0.27 in the aquifer solids. Regarding horizontal distribution, the concentration of PFASs in groundwater increased in downtowns and the areas recharged with lake water. In terms of vertical distribution, ΣPFASs decreased with the increase of depth, and more PFASs adsorbed on clay particles in the aquifer. The total oxidable precursor analysis showed that 8:2 FT and 4:2 FT were the dominant precursors of PFASs, resulting in an increment of 0.1-4 ng/L PFASs. Hydrogen and oxygen stable isotope compositions suggest similar sources between surface water and groundwater in the study area, while principal component analysis and Bayesian inference also indicate that surface water is an important source of groundwater PFASs. The annual infiltration PFASs to groundwater from Ulansuhai was estimated by the water balance approach to be 9.39 kg. Results highlight the influence of agricultural irrigation activities and lake infiltration on groundwater PFASs in the arid region.
由于高蒸发率和密集灌溉活动，干旱/半干旱地区地表水和地下水频繁交换，影响了全氟和多氟烷基物质（PFASs）的迁移和转化，并威胁到饮用水安全。本研究分析了从中国北方典型干旱地区河套灌区采集的地表水、地下水、土壤和含水层固体样品中的遗留PFASs及其潜在前体，以探索PFASs在地表水和地下水之间的分布和转化。地表水中的总PFASs（ΣPFASs）为29 - 232 ng/L，高于地下水中的2 - 77 ng/L。土壤中的ΣPFASs为0.29 - 0.59 ng/g，高于含水层固体中的0.09 - 0.27 ng/g。在水平分布方面，市中心和湖水补给区域的地下水中PFASs浓度增加。在垂直分布方面，ΣPFASs随深度增加而降低，且更多PFASs吸附在含水层中的粘土颗粒上。总可氧化前体分析表明，8:2氟调聚物醇和4:2氟调聚物醇是PFASs的主要前体，导致PFASs增加0.1 - 4 ng/L。氢和氧稳定同位素组成表明研究区域地表水和地下水来源相似，而主成分分析和贝叶斯推断也表明地表水是地下水PFASs的重要来源。通过水平衡方法估算，乌梁素海每年向地下水渗入的PFASs为9.39 kg。结果突出了农业灌溉活动和湖泊入渗对干旱地区地下水PFASs的影响。
