Microplastics as Trojan horses: Vectors of pathogens, pollutants, and antimicrobial resistance genes

Abstract

Microplastics (MPs) have emerged as pervasive environmental pollutants, acting as “Trojan horses” that carry pathogens, antibiotic-resistant bacteria, and antibiotic resistance genes, thereby posing significant threats to ecosystems and public health. This review synthesizes cutting-edge research on the triple role of MPs as persistent reservoirs, vectors for hazardous pollutants, and promoters of horizontal gene transfer, which exacerbates the spread of resistance genes. We explore the formation of a unique microbial niche on MPs, called the plastisphere that fosters biofilm development and pathogen colonization, highlighting its role in altering microbial communities and biogeochemical cycles. The physicochemical properties of MPs, such as size, surface charge, and polymer type, critically influence their interactions with pathogens and pollutants thereby enhancing their ecological and toxicological impacts. Despite advances, gaps remain in understanding long-term ecological consequences and effective mitigation strategies. We, herein, underscore the urgent need for interdisciplinary approaches to address MPs as a nexus of environmental, microbial, and public health challenges.