Abstract
Wastewater (WW) reuse is expected to be increasingly indispensable in future water management to mitigate water scarcity. However, this increases the risk of antibiotic resistance (AR) dissemination via irrigation. Herein, a conventional (chlorination) and an advanced oxidation process (heterogeneous photocatalysis (HPC)) were used to disinfect urban WW to the same target of Escherichia coli <10 CFU/100 mL and used to irrigate lettuce plants (Lactuca sativa) set up in four groups, each receiving one of four water types, secondary WW (positive control), fresh water (negative control), chlorinated WW, and HPC WW. Four genes were monitored in water and soil, 16S rRNA as an indicator of total bacterial load, intI1 as a gene commonly associated with anthropogenic activity and AR, and two AR genes blaOXA-10 and qnrS. Irrigation with secondary WW resulted in higher dry soil levels of intI1 (from 1.4 × 104 copies/g before irrigation to 3.3 × 105 copies/g after). HPC-treated wastewater showed higher copy numbers of intI1 in the irrigated soil than chlorination, but the opposite was true for blaOXA-10. The results indicate that the current treatment is insufficient to prevent dissemination of AR markers and that HPC does not offer a clear advantage over chlorination.
Highlights
Water scarcity is a growing global problem, and it is estimated that more than 3 billion people experience severe water scarcity for at least 3 months every year.[1]
1529 954 3600 350 31 other coliforms (CFU/mL) 3777 1317 6550 2200 31. This water was used for irrigation as is for the spiked wastewater series as well as used as feed WW for disinfection with both heterogeneous photocatalysis (HPC) and chlorination to the target of
Masses of the plants in these two groups were not different (p > 0.05) (Figure 3). While it is commonly reported in the literature that the degradation of selected bacterial genes in wastewater using various disinfection processes under real or realistic conditions is low,[31,41−43] this was especially the case
Summary
Water scarcity is a growing global problem, and it is estimated that more than 3 billion people experience severe water scarcity for at least 3 months every year.[1]. The opportunity of expanding the scale of tWW reuse for agricultural irrigation comes with numerous potential issues. Some issues, such as soil salinity and hydrophobicity, are better understood.[7] Other issues pertaining to wastewater reuse and the effects of organic pollutants (such as pharmaceuticals including antibiotics) and environmental antibiotic resistance (AR) dissemination are still in an early research phase.[8−10]
Sign-in/Register to view highlights & summary Sign-in/Register to access full text options 
Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
