Abstract

The Zarqa river (ZR) in Jordan receives >300,000 m(3) day(-1) 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 (Mont ha spicata) and lettuce (Lactuca sativa)) along the ZR flow path between Assamra wwrp and Jerash spring. The combined PFAS concentration (Sigma PFASs) in Assamra WWTP effluent (14-24 ng L-1) was comparable to that in influent (10-15 ng L-1), indicating poor removal of PFASs. The dominant PFAS in influent was perfluorodecanoate (PFDA), while perfluorooctanoate (PFOA) and perfluoropentanoate (PFPeA) dominated in effluent. Sigma PFASs in an unaffected upstream tributary (Sukhna station) was 4.7-5.4 ng L-1. Farther downstream, ZR water contained 16-27 ng L-1, with PFPeA. PFOA and PFDA dominating, and these levels did not change along the flow path to Jerash spring. Sigma PFASs in soil was generally low, 340 +/- 150 pg g(-1) dry weight (dw) in alfalfa soil (mainly PFOA and PFDA) and 710 +/- 420 pg g(-1) dw in mint soil and 970 +/- 800 pg g(-1) dw in lettuce soil (mainly linear perfluorooctane sulfonate (L-PFOS) in both cases). Soil-water partitioning coefficient (K-d ) was generally low in all soils (range 24-62 L kg(-1), 20-46 L kg(-1) and 28 L kg(-1) 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. (C) 2020 Elsevier B.V. All rights reserved.

Keywords

Apiculture; Alfalfa; Plant uptake; PFAS; PFOA; PFDA; PFPeA; Soil; Wastewater-irrigated; Mint; Zama river

Published in

Science of the Total Environment
2020, Volume: 716, article number: 137057

SLU Authors

• Shigei, Makoto

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

• Ahrens, Lutz

  • Department of Aquatic Sciences and Assessment, Swedish University of Agricultural Sciences
    

• Dalahmeh, Sahar

  • Department of Energy and Technology, Swedish University of Agricultural Sciences
    

Sustainable Development Goals

SDG6 Ensure availability and sustainable management of water and sanitation for all
SDG3 Ensure healthy lives and promote well-being for all at all ages


UKÄ Subject classification

Environmental Sciences related to Agriculture and Land-use


Publication identifier

DOI: https://doi.org/10.1016/j.scitotenv.2020.137057

Permanent link to this page (URI)

https://res.slu.se/id/publ/104535