Killing Two Crises with One Spark

Abstract

Global water scarcity and antimicrobial resistance (AMR) represent two escalating crises that urgently demand integrated and effective solutions. While wastewater reuse is increasingly promoted as a strategy to alleviate water scarcity, conventional treatment processes often fail to eliminate persistent contaminants and antibiotic-resistant microorganisms. Cold plasma (CP), a non-thermal advanced oxidation process, has demonstrated the strong potential to simultaneously inactivate pathogens and degrade micropollutants. CP generates a diverse mix of reactive oxygen and nitrogen species (ROS and RNS), as well as UV photons and charged particles, capable of breaking down complex contaminants and inducing irreversible damage to microbial cells. Laboratory studies have reported bacterial log reductions ranging from 1 to >8–9 log10, with Gram-negative species such as E. coli and Pseudomonas aeruginosa showing higher susceptibility than Gram-positive bacteria. The inactivation of endospores and mixed-species biofilms has also been achieved under optimized CP conditions. Viral inactivation studies, including MS2 bacteriophage and norovirus surrogates, have demonstrated reductions >99.99%, with exposure times as short as 0.12 s. CP has further shown the capacity to degrade antibiotic residues such as ciprofloxacin and sulfamethoxazole by >90% and to reduce ARGs (e.g., bla, sul, and tet) in hospital wastewater. This perspective critically examines the mechanisms and current applications of CP in wastewater treatment, identifies the operational and scalability challenges, and outlines a research agenda for integrating CP into future water reuse frameworks targeting AMR mitigation and sustainable water management.