Department of Energy and Technology, Swedish University of Agricultural Sciences (SLU), Box 7032, SE 750 07 Uppsala, Sweden.
Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences (SLU), Box 7050, SE 750 07 Uppsala, Sweden.
Sci Total Environ. 2020 May 10;716:137057. doi: 10.1016/j.scitotenv.2020.137057. Epub 2020 Feb 1.
The Zarqa river (ZR) in Jordan receives >300,000 m day of wastewater effluent from Assamra wastewater treatment plant (WWTP) and is a major source of irrigation water for vegetable crops and fodder downstream. ZR water quality is therefore highly important and directly influences crop and soil quality in irrigated fields. This study investigated the occurrence and concentration of 20 per- and polyfluoroalkyl substances (PFASs) in Assamra wastewater, ZR water, soils and crop plants (alfalfa (Medicago sativa), mint (Mentha spicata) and lettuce (Lactuca sativa)) along the ZR flow path between Assamra WWTP and Jerash spring. The combined PFAS concentration (∑PFASs) in Assamra WWTP effluent (14-24 ng L) was comparable to that in influent (10-15 ng L), indicating poor removal of PFASs. The dominant PFAS in influent was perfluorodecanoate (PFDA), while perfluorooctanoate (PFOA) and perfluoropentanoate (PFPeA) dominated in effluent. ∑PFASs in an unaffected upstream tributary (Sukhna station) was 4.7-5.4 ng L. Farther downstream, ZR water contained 16-27 ng L, with PFPeA, PFOA and PFDA dominating, and these levels did not change along the flow path to Jerash spring. ∑PFASs in soil was generally low, 340 ± 150 pg g dry weight (dw) in alfalfa soil (mainly PFOA and PFDA) and 710 ± 420 pg g dw in mint soil and 970 ± 800 pg g dw in lettuce soil (mainly linear perfluorooctane sulfonate (L-PFOS) in both cases). Soil-water partitioning coefficient (K) was generally low in all soils (range 24-62 L kg, 20-46 L kg and 28 L kg for PFOA, PFDA and L-PFHxS, respectively). No PFASs were detected in alfalfa and mint plants. Overall, this investigation demonstrated that PFAS contamination in wastewater, surface water and soil in the ZR basin is very low in a global comparison, and that there is no accumulation of PFASs in the food and feed crops studied.
约旦的扎尔卡河（ZR）每天接收来自阿萨姆拉废水处理厂（WWTP）超过 30 万立方米的废水，是下游蔬菜作物和饲料灌溉用水的主要来源。因此，ZR 水的质量非常重要，直接影响到灌溉农田中的作物和土壤质量。本研究调查了 20 种全氟和多氟烷基物质（PFASs）在阿萨姆拉废水、ZR 水、土壤和作物植物（紫花苜蓿（Medicago sativa）、薄荷（Mentha spicata）和生菜（Lactuca sativa））中的存在和浓度，这些植物沿着 ZR 从阿萨姆拉 WWTP 到杰拉什泉的流动路径分布。阿萨姆拉 WWTP 废水（14-24ng/L）中的 PFAS 总浓度（∑PFASs）与进水相当（10-15ng/L），表明 PFASs 的去除效果不佳。进水的主要 PFAS 是全氟癸酸（PFDA），而在废水中，全氟辛酸（PFOA）和全氟戊酸（PFPeA）占主导地位。未受影响的上游支流（苏赫纳站）中的∑PFASs 为 4.7-5.4ng/L。再往下游，ZR 水中含有 16-27ng/L，主要含有 PFPeA、PFOA 和 PFDA，这些水平在流向杰拉什泉的过程中没有变化。紫花苜蓿土壤（主要为 PFOA 和 PFDA）中∑PFASs 一般较低，为 340±150pg/g 干重（dw），薄荷土壤中为 710±420pg/g dw，生菜土壤中为 970±800pg/g dw（两种情况下均主要为线性全氟辛烷磺酸（L-PFOS））。所有土壤中土壤-水分配系数（K）均较低（分别为 PFOA、PFDA 和 L-PFHxS 的 24-62L/kg、20-46L/kg 和 28L/kg）。在紫花苜蓿和薄荷植物中均未检测到 PFASs。总的来说，这项研究表明，在全球范围内，扎尔卡河流域废水中、地表水和土壤中的 PFAS 污染非常低，在所研究的食物和饲料作物中没有 PFASs 的积累。
