Priyanka Singh, Murugesh Shivashankar
Microplastics (MPs), defined as plastic particles smaller than 5 mm, are emerging contaminants of global concern due to their persistence and ecological risks. Although widely studied in aquatic systems, their effects on terrestrial environments especially soils remain underexplored. Soils act as major sinks and secondary sources of MPs, where these particles interact with microorganisms, plants, and extracellular polymeric substances (EPS). EPS, secreted by microbes, are key to soil structure, nutrient cycling, and microbial aggregation. The introduction of MPs can disturb these systems by altering microbial community composition, EPS production, and nutrient dynamics, leading to changes in soil aggregation, water retention, and fertility. Furthermore, MPs can adsorb and transport toxic additives and heavy metals, potentially affecting plant root development, nutrient uptake, and growth. Such interactions may disrupt soil health and ecosystem functioning. Understanding the mechanisms of MP–EPS interactions is therefore essential to evaluate their influence on soil processes, plant productivity, and biogeochemical cycles. This review summarizes current knowledge on MPs in soil and sludge environments, emphasizing their effects and interaction to EPS and its effect on soil health and plant growth, and highlights research gaps crucial for developing sustainable management strategies.