Transport Dynamics and Physiological Responses of Polystyrene Nanoplastics in Pakchoi: Implications for Food Safety and Environmental Health.

Nanoplastics (NPs) have become a new environmental pollutant that causes serious harm to food safety. They can be absorbed by plants, transported to edible parts, transmitted to the human body along the food chain, and can threaten human health. The research investigated the transport and accumulation pathways of polystyrene NPs (PS-NPs) at varying concentrations using red fluorescence labeling. An analysis was conducted on the response of pakchoi to PS-NPs through a combination of transcriptional and physiological experiments. PS-NPs enter the xylem vessel of the root, subsequently carried to the petiole through transpirational tension, and eventually transported from the petiole's xylem vessels to the leaf. PS-NPs induced the accumulation of reactive oxygen species (ROS), which led to oxidative damage. In addition, it also disturbed the homeostasis of endogenous hormones and affected the growth of pakchoi. These findings help people understand the adverse effects of NPs on crops and increase attention to the hazards of NPs.