Abstract

This study was carried out to determine acute oral toxicity and histopathological effects associated with consumption of Euphorbia heterophylla ethanolic extract using 9 to 10 weeks old Albino mice randomized in six groups. The five groups were orally administered with single graded doses of plant extract at 1500, 2000, 2500, 3500 and 4000 mg/kg body weight while the sixth group was administered 1 ml of physiological saline and the animals were observed for toxicity signs and death. Viscera organs were obtained after cervical dislocation for histopathological assessment. The graded extracts induced dose-dependent toxicity signs with major clinical manifestation prior to death including: polyurea, circling, paralysis, thirst, loss of appetite and gait, tachypnea, dehydration and stupor. The major dose- dependent histopathological lesions included: Hemorrhages, congestion, peri-vascular degeneration and necrosis in viscera organs in the groups that received 2000 to 4000 mg/kg body weight. The 24 h median lethal dose was 2831 mg/kg body weight and the 95% confidence interval of median lethal dose was 2490 to 3218 mg/kg body weight and R² is 0.96 indicating E. heterophylla is of low toxicity. The study demonstrated the toxicity potential associated with uncontrolled use of this plant by the communities. Toxicological studies of sub chronic and chronic toxicity, as well as in vitro mutagenicity and genotoxicity need to be conducted considering the well claimed prolonged use of the plant extract to assess the effect prolonged use on animals.

Key words: Acute oral toxicity, histopathological lessions, Euphorbia heterophylla.