Removal of antibiotic resistance genes in various water resources recovery facilities

Kucukunsal S., İÇGEN B.

WATER ENVIRONMENT RESEARCH, cilt.92, ss.911-921, 2020 (SCI İndekslerine Giren Dergi) identifier identifier identifier

  • Cilt numarası: 92 Konu: 6
  • Basım Tarihi: 2020
  • Doi Numarası: 10.1002/wer.1286
  • Sayfa Sayıları: ss.911-921


Water resources recovery facilities (WWTPs) are hotspots for antibiotic resistance genes (ARGs) and pose a significant threat to environments. Therefore, ARG removal efficiencies of WWTPs are of great importance. In this study, conventional activated sludge (CAS), biological nutrient removal (BNR), sequencing batch reactor (SBR), membrane bioreactor (MBR), package MBR, and WWTP with coagulation-flocculation and UV disinfection units were investigated in terms of their removal efficiencies on overall bacterial genes with 16S rDNA and seven ARGs including the genes aadA, bla(CTX-M), cmlA, ermB, sul1, tetA, and qnrS corresponding to commonly used antibiotics aminoglycosides, beta-lactams, amphenicols, macrolides-lincosamides-streptogramins, sulfonamides-trimethoprim, tetracyclines, and quinolones, respectively. Seasonal abundance of overall genes and ARGs in influents and effluents of each WWTPs was determined by quantitative polymerase chain reaction. Membrane bioreactor and package MBR systems showed the highest removal efficiency up to 5-log reductions. Seasonal changes affected ARG removal efficiencies of BNR and CAS significantly (p < 0.05). The lowest log reductions were determined in summer for BNR and in both autumn and winter for CAS. The abundance of the genes increased in sludge treatment of CAS. In all WWTPs tested, ARG removal rates were correlated with the 16S rDNA gene removal (p > 0.05). The results elucidated that the removal mechanism was not ARG-specific. Practitioner points