Micro and nanoplastics as emerging stressors influencing plant metabolism and nutrient dynamics

The widespread contamination of terrestrial ecosystems with micro and nanoplastics (MNPs) poses emerging risks to plant health, food safety, and agroecosystem sustainability. Growing evidence suggests that MNPs interact with plants through multiple exposure pathways, influencing their growth, metabolism, and nutrient dynamics. This review synthesizes current research on the sources of MNPs in agricultural soils, their entry and transport within plants, and their potential impacts on plant primary and secondary metabolism. Particular emphasis is placed on how MNP exposure may alter nutrient allocation, metabolic regulation, and the nutritional quality of edible plant tissues, thereby raising concerns for crop productivity, food security, and human dietary exposure. The review also discusses how soil structural changes, microbial disruption, and contaminant vector effects may indirectly influence plant health and agroecosystem functioning. While current evidence indicates that MNPs could affect plant performance and nutritional outcomes, substantial uncertainties remain due to the predominance of short-term laboratory studies. Key knowledge gaps and future research directions are identified, emphasizing the need for field-scale investigations and integrated risk assessments to better evaluate the long-term implications of MNP contamination in agricultural systems.