Sub-lethal effects of polystyrene nanoplastics on some physiological indices of common carp (Cyprinus carpio)

The significant development of nanotechnology and the widespread use of nanomaterials in various industrial fields make it necessary to investigate their destructive effects on biological systems. Therefore, in the use of nanoparticles, attention should be paid to their toxicity. This research was conducted with the aim of investigating the ecophysiological responses of common carp in exposure to nanoplastic-polystyrene as a widely used polymer. A total of 84 specimens of common carp with an average weight of 30±1.5 g, were examined in 4 food treatments (control with commercial food and treatments with diet containing 0.1, 0.5, 1 ml nano-polystyrene emulsion). At the end of the 28 days test period, serum and mucus samples were collected. The results showed, different concentrations of polystyrene nanoplastics had no significant effect on total blood serum protein indices (P>0.05). But the amount of glucose in the concentration of 1 ml (the highest concentration) increased significantly compared to the control group (P<0.05). The experimental treatments caused a significant increase in the amount of soluble mucus protein (P<0.05). Also, experimental treatments caused a significant increase and decrease of ALT and AST in blood serum, respectively (P<0.05). Generally, the results showed that polystyrene nano-plastic increases stress and adverse physiological responses in common carp and these harmful effects are more evident in higher concentrations.