Microplastics in agricultural soils: sources, soil–plant interactions, ecotoxicological effects and food security concerns

Abstract

The problem of microplastic contamination in agricultural soils is becoming a significant environmental concern due to its prevalence and potential effects on soil health, crop productivity, and food security. The sources, ecological routes, and ecotoxicology of microplastics within agroecosystems were thoroughly analyzed in this review. Plastic enters the soil system in various ways, such as plastic mulching systems, organic amendments, wastewater irrigation, and atmospheric deposition, and in the latter case, it generates long-term accumulation and sustainability of microplastics. The presence of microplastics alters the physicochemical properties of the soil, disrupts microbial communities and nutrient cycling, thereby affecting soil function. Moreover, plant systems can absorb microplastics through a series of routes and transport them to aerial structures, which may raise concerns about their entry into the food chain and their consequences for human health. A distinguishing feature of this review is its integrated soil–microplastic–microbe–plant perspective, linking microplastic sources and fate with soil functioning, microbial processes, plant uptake and translocation, crop productivity, and food-security concerns. It further adopts a systems-level approach by examining interactions among soil properties, rhizosphere processes, microplastic mobility, co-contaminants, and plant responses, while identifying key methodological and field-scale limitations relevant to agricultural risk assessment. Further, critical gaps in knowledge, such as the necessity of long-term field studies, standardized detection procedures, and a more comprehensive understanding of microplastic behavior in realistic environments, are outlined. To overcome these issues, it is critical to address them in order to develop effective mitigation measures and sustainable agricultural production in the context of growing plastic pollution.