Keywords activated sludge process antimicrobial resistance extracellular DNA freshwater systems horizontal gene transfer metagenome mobile genetic elements public health wastewater Research topic(s) CP: microbiology Introduction The emergence and persistence of antimicrobial resistance (AMR) in the environment represents a growing risk to public health and ecological stability.1,2,3,4 Previous reports suggest that this threat is largely driven by the continuous spread of antimicrobial...