Toxicity of cypermethrin on fingerlings of rohu: Labeo rohita (ham)

Abstract

The aim of the present investigation was to standardize the lethal concentration (LC50) and safe concentration for the selected biocide cypermethrin on fingerlings of Labeo rohita and by following acute toxicity test. The effect was assessed on the basis of results obtained in the acute toxicity test. The static bioassay methodology was followed to find out the 24h, 48h, 72h and 96 h LC50 values for cypermethrin. Experiment was carried out with three replicates under a treatment. The 24h, 48h, 72h and 96 h LC50 values for cypermethrin was calculated to be be 3.84 (3.68 to 3.86) µg/l; 3.66 (3.63 to 3.71) µg/l; 3.53 (3.50 to 3.55) µg/l and 3.48 (3.32 to 3.63) µg/l respectively. The safe application factors for cypermethrin were 1.049 µg/l and presumable harmless concentration were 0.997 µg/l.