Repeated dose toxicity of deltamethrin in rats

OBJECTIVE : To investigate the short-term toxicity of deltamethrin in rats.
MATERIALS AND METHODS : Deltamethrin was dissolved in dimethyl sulphoxide and the oral LD₅₀ was calculated to be 150 mg/kg. Then groups of rats were given repeated daily oral dose (1/10 LD₅₀) of deltamethrin for 30 days. The animals were killed on 31^st day. Activities of various enzymes, cytochrome P₄₅₀ and b₅ contents in liver, hepatic antioxidant status, tissue residue concentration, haemogram and pathological changes were studied.
RESULTS : Deltamethrin increased the serum aminotransaminase, alkaline phosphatase, lactate dehydrogenase activities and blood glucose level significantly. Deltamethrin decreased PCV and Hb level and the liver cytochrome P₄₅₀ content significantly. Considerable amount of residues were present in different tissues. It increased malondialdehyde level, while decreased the activities of catalase, superoxide dismutase, reduced glutathione and glycogen levels in liver significantly. Mild to moderate histological alterations were observed in lungs, liver, stomach, kidney, testes and cerebellum.
CONCLUSION : Repeated dose toxicity studies of deltamethrin at 1/10 LD₅₀ altered the biochemical parameters; decrease cytochrome P₄₅₀ content, antioxidant status, which correlated with histopathological changes with considerable amount in tissue residues.