Preliminary acute toxicity study on imidacloprid in Swiss albino mice

Aim: To ascertain the maximum tolerated dose (MTD) and to investigate the acute oral toxic effects of imidacloprid towards Swiss albino male mice. Materials and Methods: The MTD of imidacloprid was determined in pilot dose range finding study following the standard method. Animals were observed for toxic signs and symptoms after oral administration of MTD of imidacloprid in single dose. th The body weights of animals were recorded on alternate day. Animals were sacrificed on 14 day and changes in hematological parameters (Hb, TEC, TLC and DLC) and morphometric measurements (length, breadth, thickness and weight) of various body organs (heart, liver, spleen, kidney, testis and epididymis) were examined. The student's t-test was applied to statistically analyze the results. Results: The MTD of imidacloprid was determined to be 110 mg/kg body weight. The sign and symptoms of acute toxicity were ataxia, rigidity and fasciculation of muscles, protrusion of eye ball and tremors of head. Imidacloprid treatment resulted in decreased body weight gain as compared to the control group. The changes in hematological parameters were not significant between imidacloprid treated and control groups. Also the values of relative organ weights and morphometric measurements of various body organs did not differ significantly between the control and imidacloprid treated animals. Conclusions: MTD of imidacloprid in Swiss albino male mice through oral route was determined for the first time. Study revealed a non-toxic effect of imidacloprid on body weight, relative organs weight, hematological parameters and morphometric measurements of various body organs in mice.