The interplay between antimicrobial resistance genes and emerging contaminants in wastewater treatment plants: Key players in One Health

Abstract

Background: Wastewater treatment plants (WWTPs) are recognised as significant reservoirs of antimicrobial resistance (AMR) and are key sources and sinks of multiple emerging contaminants (ECs). The diverse ECs in WWTPs can exert selective pressure on microbial communities, driving the development of AMR and spread of antimicrobial resistance genes (ARGs). This association raises critical ‘One Health’ concerns regarding the role of WWTPs. Understanding the complex interplay between ECs and AMR in these environments is crucial to addressing this global health challenge. Main body: This study investigates the occurrence and fate of ECs in WWTPs, the factors influencing AMR development, and the distribution of prominent ARGs within WWTPs. Our findings reveal that sulfonamide and tetracycline resistance genes (sul and tet) are the most abundant ARGs in WWTPs. Fluoroquinolones, macrolides, and sulfonamides are the most prevalent antibiotic classes detected in final effluents. The interaction of these antibiotics with other environmental contaminants, such as microplastics and heavy metals, within WWTPs, contributes to ARG proliferation through mechanisms including co-resistance, cross-resistance, and co-selection. This highlights the evolving role of WWTPs from simple waste conduits to hotspots of AMR, necessitating the use of active surveillance mechanisms. Quantitative PCR (qPCR) and Next-generation sequencing (NGS) have emerged as sensitive and effective tools for ARG detection, warranting their inclusion in surveillance strategies. Conclusion: This review provides a knowledge-driven approach to identify key factors in antimicrobial surveillance related to ECs, ultimately informing targeted interventions to minimise their detrimental effects and develop effective strategies to protect global public health.