The hidden risk of microplastic-associated pathogens in aquatic environments

Increasing studies of plastisphere have raised public concern about microplastics (MPs) as vectors for pathogens, especially in aquatic environments. However, the extent to which pathogens affect human health through MPs remains unclear, as controversies persist regarding the distinct pathogen colonization on MPs as well as the transmission routes and infection probability of MP-associated pathogens from water to humans. In this review, we critically discuss whether and how pathogens approach humans via MPs, shedding light on the potential health risks involved. Drawing on cutting-edge multidisciplinary research, we show that some MPs may facilitate the growth and long-range transmission of specific pathogens in aquatic environments, ultimately increasing the risk of infection in humans. We identify MP- and pathogen-rich settings, such as wastewater treatment plants, aquaculture farms, and swimming pools, as possible sites for human exposure to MP-associated pathogens. This review emphasizes the need for further research and targeted interventions to better understand and mitigate the potential health risks associated with MP-mediated pathogen transmission. [Display omitted] •Pathogenic bacteria and viruses colonized on microplastic (MP) surfaces are reviewed.•Polymer types of MPs affect the major pathogen species colonized on MP surfaces.•Human ingestion of MPs leads to the ingestion of pathogens coated on MP surfaces.•Lack of data hinders quantifying potential health risks from MP-associated pathogens.