Microplastics and antibiotics in agricultural soil: mechanisms and implications of co-contamination

The co-contamination of agricultural soils by microplastics (MPs), antibiotics, and antibiotic resistance genes (ARGs) is an emerging environmental concern with significant ecological and public health implications. This review explores the sources, interactions, and consequences of MPs and antibiotics/ARGs co-occurrence in soil systems. Agricultural practices, such as manure application, wastewater irrigation, and sewage sludge amendment, are primary contributors to this co-contamination. MPs not only serve as physical vectors but also actively interact with antibiotics and ARGs through processes like adsorption, aging, and biofilm formation, enhancing the emergence and dissemination of resistance genes. These interactions disrupt soil physicochemical properties and microbial communities, impairing soil health and reducing crop productivity. Furthermore, the accumulation of MPs and ARGs in edible plants raises concerns about human exposure through the food chain. Emerging evidence links such exposure to health risks, including metabolic, cardiovascular, neurological, and gastrointestinal disorders. Understanding the mechanisms underlying this co-contamination is critical for informing risk assessments and guiding mitigation strategies to protect soil ecosystems and public health.