Unveiling the impact of polystyrene nanoplastics on tea seedlings: uptake, translocation, and oxidative stress‐mediated alterations
Tingting Shen, Fei Liu, Rui Zhang, Tianyuan Yang, Ping Zhang, Xiuhong Zhou, Rimao Hua, Jianfa Zong, Weiting JiaoAbstract
Background
The accumulation of nano‐plastics in terrestrial environments raises urgent concerns for crop safety, but little is known about their bioavailability and impact in perennial plants like tea ( Camellia sinensis L.). This study investigated the uptake and physiological effects of 80 nm polystyrene nano‐plastics (PS‐NPs) in hydroponically grown tea seedlings.
Result
Confocal laser scanning microscopy (CLSM) visualized PS‐NPs in root cortices and leaf tissues, confirming systemic translocation. Exposure to PS‐NPs (10–100 mg L −1 ) for durations of 1, 3 and 7 days triggered concentration‐dependent oxidative stress and defense responses: root catalase (CAT) activity was initially suppressed by 69.7% (50 mg L −1 ) but later induced 15‐fold, while leaf glutathione S‐transferase (GST) activity was significantly inhibited. Notably, theanine content in leaves increased by 77.6% at 10 mg L −1 but decreased by 70.1% at 100 mg L −1 .
Conclusion
The findings demonstrate PS‐NPs uptake and their impact on tea seedling physiology and quality‐related metabolites, underscoring potential risks to perennial crops. © 2026 Society of Chemical Industry.