The examination of tocxicological effect of some novel insecticides on Gammarus kischineffensis (Schellenberg,1937)(Crustacea: Amphipoda)

In this study the acute toxicity of indoxacarb, thiamethoxam and endosulfan on Gammarus kischineffensis (Schellenberg,1937) and the histopathological alternations caused by these pesticides in gill tissues of G. kischineffensis were aimed to be examined.In the acute toxicity tests G. kischineffensis samples were exposed to certain concentrasions of each pesticide in order to determine 24, 48, 72 and 96 hour LC50 values of these pesticides. After the range finding tests the experimental concentrations for indoxacarb were 0.0 (control), 1, 5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90 and 100 mg/l, the experimental concentrations for thiamethoxam were 0.0 (control), 2.5, 5, 7.5, 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80, 90 and 100 mg/l concentrations of this pesticide. Adjusting concentrations of endosulfan were 1.0, 2.5, 5.0, 7.5, 10.0, 12.5, 15.0, 17.5 and 20 ? g/l. After the acute toxicity study the 96 hour LC50 values found for indoxacarb, thiamethoxam and endosulfan were 20.212 mg/l, 3.751 mg/l and 1.861 ? g/l respectively.For the hitological examination, the ratios 1/10, 1/100 and 1/1000 of LC50 values found after acute toxicity study were used. At 7th and 14th days, 5 samples were taken from each pesticide group and sacrified for histolojical examination. Indoxacarb caused hemocytic infiltration, hiperplasia of epithelium, thiamethoxam caused hemocytic infiltration and vacuolization and endosulfan caused hemocytic infiltration in pillar cells, hiperplasia of epithelium.