Acute toxicity of the synthetic pyrethroid alpha-cypermethrin on the tadpoles of variable green toad, Bufotes variabilis (Amphibia:Anura)

In this study, acute toxic effects of alpha-cypermethrin were investigated in the tadpoles of Bufotes variabilis (Pallas, 1769). Tadpoles at Gosner stage 19 were exposed to 0, 0.1, 5 and 10 mu gl super(-1) of alpha-cypermethrin concentrations for 96 hours. Mortality, the changes in some morphological measurements (snout-vent length, body width, tail length, and wet weight), morphological anomalies and behavioral changes were evaluated at the end of the experiment. The 96 hours LC sub(50) value was calculated as 15.62 mu gl super(-1). Such morphological changes as axial anomaly, visceral edema, deformation of the mouth, and tail deformation were observed in 83% and 95% of the tadpoles in the groups treated with 5 and 10 mu gl super(-1) of alpha-cypermethrin. Behavioral changes such as shortening of the swimming distance and immobility were recorded in all tadpoles exposed to alpha-cypermethrin. When all findings were evaluated totally, it was concluded that alpha-cypermethrin had negative effects on the development of the tadpoles of B. variabilis.