This study was conducted to evaluate the tissue of liver, gills and kidney Rutillus caspicus exposed to concentrations of 50, 100, 150 mg of Methyl tert-butyl ether, for 7, 14, 21 days. Average water temperature of 19±1 °C, water oxygen of 7.6 ± 0.2 mg/l and zero salinity were measured. A total of 156 fishes were studied in this experiment. In the first, second and third week of the test, three...