Persistence of antibiotic resistance genes and bacterial community changes in drinking water treatment system: From drinking water source to tap water

摘要

AbstractAs emerging contaminants, antibiotic resistance genes (ARGs) have become a public concern. This study aimed to investigate the occurrence and diversity of ARGs, and variation in the composition of bacterial communities in source water, drinking water treatment plants, and tap water in the Pearl River Delta region, South China. Various ARGs were present in the different types of water. Among the 27 target ARGs,floRandsul1dominated in source water from three large rivers in the region. Pearson correlation analysis suggested thatsul1,sul2,floR, andcmlAcould be potential indicators for ARGs in water samples. The total abundance of the detected ARGs in tap water was much lower than that in source water. Sand filtration and sedimentation in drinking water treatment plants could effectively remove ARGs; in contrast, granular activated carbon filtration increased the abundance of ARGs. It was found thatPseudomonasmay be involved in the proliferation and dissemination of ARGs in the studied drinking water treatment system. Bacteria and ARGs were still present in tap water after treatment, though they were significantly reduced. More research is needed to optimize the water treatment process for ARG removal.Graphical abstractDisplay OmittedHighlights•Diverse ARGs present in different types of waters.•Sul1,sul2,floR,cmlAcould be potential indicators for ARGs in the water samples.•Sand filter and sedimentation were effective in removing ARGs.•Granular activated carbon filtration increased the ARGs abundance.•ARGs still existed in tap water after treatment despite significantly reduced.