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 with microbiota through biofilm formation, induction of oxidative stress, enrichment of antibiotic resistance genes (ARGs), and disruption of short-chain fatty acid metabolism, leading to dysbiosis and altered host immune responses. These interactions contribute to dysbiosis, altered immune responses, and increased dissemination of ARGs, which pose 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 key knowledge gaps and propose future research directions to assess the impact of microplastic exposure on ecosystems and human health.