Impacts of nanoplastics on bivalve: Fluorescence tracing of organ accumulation, oxidative stress and damage.

• Fluorescence was used to track the accumulation of nanoplastics in C. fluminea. • Like microplastics, nanoplastics were observed to aggregate in bivalves. • The uptake and excretion of nanoplastics were impacted by the neurotoxicity. • Nanoplastic-induced damage to the liver and gut of C. fluminea is firstly reported. The outcomes of this research offer novel insights into the toxic effects of nanoparticles (i.e., nanoplastics or other nanomaterials) on the benthos. Herein, this study aimed to evaluate the accumulation pathway, distribution characteristics and potential biotoxicity of polystyrene nanoplastics in C. fluminea. The results revealed that nanoplastics could accumulate in the mantle through adherence, in the visceral mass through ingestion and in the gill through respiration. The gill, intestine and stomach were the main accumulation organs for nanoplastics. The aggregation of nanoplastics was observed in C. fluminea , which may exacerbate their biotoxicity. Moreover, oxidative stress was observed in the visceral mass, gill and mantle. Liver damage, neurotoxicity and intestinal inflammation were caused by imbalance in the antioxidation system. Analysis of IBR values showed that the visceral mass had a more effective response to oxidative stress than the gill and mantle after exposure to nanoplastics. [ABSTRACT FROM AUTHOR]