Subacute oral toxicity of endosulfan in male new zealand white rabbits.

ABSTRACT The present study was conducted using 6 to 8 month old New Zealand white male rabbits (nine rabbits per treatment group). Daily gavages of 3, 1.5, 0.75, or 0 mg endosulfan/kg BW in corn oil resulted in the death of five (55%), three (33%), zero (0%), and zero (0%) rabbits, respectively, in 30 days. All rabbits were monitored for any observable toxic symptoms throughout the experimental period (30 d) and they also were weighed weekly to monitor body weight gain. All deaths occurred within the first 3 weeks and nervous symptoms were observed only for a few minutes before death. Alterations recorded in hematological parameters within the groups (hemoglobin, packed cell volume, and total erythrocyte count) were due to endosulfan exposure. Serum alkaline phosphatase (ALP) and aspartate aminotransferase (AST) levels were significantly elevated in the 3 mg/kg dose group. Gross post-mortem and histopathological changes in various organs (lung, liver, kidney, and testes) of rabbits treated with endosulfan were observed with typical organochlorine dose-dependent signs of toxicity. Although some animals appeared to adjust to relatively high daily doses of endosulfan for 30 days, biochemical and histological evidence indicated varied liver and kidney damage relative to dosage administered to these animals. The current subacute (30 day) study suggested a NOAEL of 0.75 mg endosulfan/kg in New Zealand white rabbits.