Hybrid advanced oxidation processes counter emerging antimicrobial resistance dissemination by disrupting horizontal gene transfer pathways

Abstract

Antibiotic resistance genes (ARGs) and resistance-carrying bacteriophages represent a critical category of emerging contaminants driving the environmental dissemination of antimicrobial resistance (AMR). Their persistence through wastewater treatment and capacity to mediate horizontal gene transfer remain inadequately controlled by conventional disinfection. This study developed and applied an integrated multi-endpoint framework to evaluate ozone (O3), O3/hydrogen peroxide (O3/H2O2), and O3/hydrodynamic cavitation (O3/HC) for AMR mitigation across three independent real wastewater sampling events. Endpoints included bacterial enumeration, quantitative PCR targeting 26 ARGs and 11 pathogens, DNA integrity profiling, bacteriophage infectivity assays, and physicochemical monitoring. Hybrid advanced oxidation processes (AOPs) achieved greater than 98% suppression of resistant bacteria and resistance genes within 120 min, fragmented wastewater DNA, and completely inactivated bacteriophages within 30 min, and simultaneously disrupting transformation, transduction, and conjugation-mediated HGT. This framework offers a transferable, evidence-based approach for evaluating wastewater treatment technologies against the full spectrum of AMR dissemination risk.