Evaluation of the ability of Nano clay on decrease of toxicity ‎effects of environmental pollutants on the Caspian Sea ‎Kutum (Rutilus frisii kutum)‎

Abstract: When pesticides are present in high concentrations in the environment causing ýirreparable, metabolic, physiologic and structural damage on the organisms. Diazinon and ýDeltamethrin are of the most widely used agricultural pesticides in the northern Iran that can ýenter aquatic ecosystems. Anatropous fishes like Kutum have most reactions with pollutants ýbecause of their spawning in the first spring. Kutum is suitable species for toxicity testing in the ýsouthern coast of the Caspian Sea, due to the wide distribution. The aim of present study was to ýdetermine the effects of Nano-clay in reducing the fatality rate of diazinon and Deltamethrin on ýthe Caspian Sea Kutum. 210 pcs kutum with a mean weight of 24 g were collected from fish ýstocks Syjval and after two weeks of adaptation in laboratory toxicity tests carried out for 96 ýhours. The results of this study showed that 500 mg / L clay is the greatest losses while 1000 mg / ýL Nano clay increased the death toll is likely to rise due to high water and mud contaminated ýfish is breathing difficulty.ý