From soil to shoot plant responses to polystyrene nanoplastics and relevance for sustainable food systems

Within the One Health framework, plants represent a critical interface between environmental contaminants and the food web. Among emerging pollutants, polystyrene nanoplastics (PS-NPs) are particularly concerning due to their small size, high surface reactivity, and ability to cross biological barriers. PS-NPs can be potentially internalized through roots or leaves, translocated to other organs, and, in some cases, accumulated in edible tissues, posing risks to food safety and human health. This review explores PS-NPs behavior in plants, focusing on uptake mechanisms, translocation pathways, accumulation sites, and physiological and molecular responses in different plant species, both model and crops. While wheat shows tolerance even at high PS-NPs concentrations, species like rice, lettuce, and garlic exhibit growth inhibition, oxidative stress, nutrient imbalances, and genotoxic effects. Transcriptomic studies confirm that PS-NPs alter gene expression linked to redox homeostasis, hormone signaling, and stress responses, though the specific pathways affected differ across species and conditions. Overall, plant species and PS-NPs concentration emerge as key factors determining phytotoxic outcomes. The detection of PS-NPs in edible plant parts highlights a tangible risk for humans. Standardized analytical methods, realistic scenarios, and the identification of molecular markers of tolerance are urgently needed to better assess and mitigate the impact of PS-NPs on agriculture and food safety within the One Health perspective.