Variation of antibiotic resistance genes in municipal wastewater treatment plant with A2O-MBR system

Abstract

The variation of five antibiotic resistance genes (ARGs)-tetG, tetW, tetX, sul1, and intI1-in a full-scale municipal wastewater treatment plant with A(2)O-MBR system was studied. The concentrations of five resistance genes both in influent and in membrane bioreactor (MBR) effluent decreased as sul1 > intI1 > tetX > tetG > tetW, and an abundance of sul1 was statistically higher than three other tetracycline resistance genes (tetG, tetW, and tetX) (p < 0.05). The concentrations of five ARGs in the influent were all higher in spring (median 10(5.81)-10(7.32) copies mL(-1)) than they were in other seasons, and tetW, tetX, and sul1 reached its lowest concentration in autumn (10(4.61)-10(6.81) copies mL(-1)). The concentration of ARGs in wastewater decreased in the anaerobic effluent and anoxic effluent, but increased in the aerobic effluent, and then sharply declined in the MBR effluent. The reduction of tetW, intI1, and sul1 was all significantly positively correlated with the reduction of 16S ribosomal DNA (rDNA) in the wastewater treatment process (p < 0.01). The concentration of ARGs (copies mg(-1)) in sludge samples increased along the treatment process, but the abundance of five ARGs (ratio of ARGs to 16S rDNA) remained the same from anaerobic to anoxic to aerobic basins, while an increment ratio in MBR was observed for all ARGs.

Removal of antibiotic resistance genes in an anaerobic membrane bioreactor treating primary clarifier effluent at 20 °C

“…During the biological process, ARGs increased in an aerobic bioreactor in one full-scale study, but were significantly lower in MBR filtrate compared to the wastewater treated. 29 The ARGs decrease was correlated to decreased 16S rRNA gene copies. 29 In general, aerobic MBR treatment results in higher removal of ARGs than conventional activated sludge treatment, 30 but little research is available that describes how AnMBR processes impact ARG fate.…”

Reactive Barriers for Renaturalization of Reclaimed Water during Soil Aquifer Treatment

“…However, some pieces of side evidence appear hopeful. The generation of anaerobic areas should help because the activity of microorganisms is reduced and the transfer of ARG is inhibited [99]. The presence of plants has proven efficient at removing ARGs in constructed wetlands [100].…”

Effect of pyrolysis on the removal of antibiotic resistance genes and class I integrons from municipal wastewater biosolids

“…The results observed in this study are congruent with previous studies that have reported sul1 as one of the most prevalent ARGs detected in municipal WRRFs. 18,25,63 ARGs such as sulfonamide resistance genes can proliferate in biological processes at WRRFs and previous studies have reported sul1 concentrations of up to 10 11 copies/g dry weight in dewatered sludge. 25 The sul1 gene is generally harbored in class 1 integrons containing multiple resistance genes, and encodes dihydropteroate synthase that is not inhibited by sulfonamides.…”