The Effect of the Effluent from a Small-Scale Conventional Wastewater Treatment Plant Treating Municipal Wastewater on the Composition and Abundance of the Microbial Community, Antibiotic Resistome, and Pathogens in the Sediment and Water of a Receiving Stream

The effluents of wastewater treatment plants (WWTPs) are major contributors nutrients, microbes—including those carrying antibiotic resistance genes (ARGs)—and pathogens to receiving waterbodies. effect the effluent a small-scale activated sludge WWTP treating municipal on composition and abundance microbial community as well resistome in sediment water stream river was studied using metagenome sequencing quantitative approach. Elevated Bacteroidetes proportions prokaryotic community, heightened sulfonamide aminoglycoside determinants proportions, an increase up three orders magnitude sul1–sul2–aadA–blaOXA2 gene cluster abundances were recorded sediments 0.3 km downstream discharge point. Further downstream, gradual recovery affected communities along distance gradient from recorded, culminating mostly comparable state parameters 3.7 upstream Archaea, especially Methanosarcina, Methanothrix, Methanoregula, formed substantial proportion sediment, linked spread ARGs. Opportunistic environmental-origin predominant bacterial communities, with Citrobacter freundii being elevated close vicinity