Microplastics—The Microbiota Interactions: Mechanisms, Multi-Omics Insights and Health Implications

Microplastics (MPs) are pervasive environmental contaminants detected in terrestrial, aquatic, and human systems. Emerging evidence indicates that MPs interact dynamically with microbiota across ecosystems, including host-associated microbiota such as the human gut, influencing microbial composition, metabolic activity, and functional potential. These interactions contribute to dysbiosis, altered immune responses, and increased dissemination of antibiotic resistance genes (ARGs), posing health risks. This review synthesizes current knowledge on mechanisms of microplastic–microbiota interactions, highlighting evidence from in vitro, in vivo, and environmental studies. We discuss methodological challenges, including variability in particle types, concentrations, aging, and analytical approaches. Recent advances in multi-omics techniques provide deeper mechanistic understanding and reveal functional consequences of MP exposure. We outline critical knowledge gaps and propose future research directions, aiming to provide a comprehensive framework for evaluating ecological and human health consequences of microplastic exposure.