Response of rats to repeated oral administration of endosulfan.

Male and female albino rats given different oral doses (0.75, 2.5, 5.0 and 0.25, 0.75, 1.5 mg/kg/D) of endosulfan respectively for a period of 30 days elicited signs of toxicity such as hyperexcitability, tremor, dyspnea and salivation for a brief period. At the tested dose levels, endosulfan produced no significant change in the organ body weight ratio, biochemical, histological, haematological and fertility indices. Residue analysis using GLC techniques of different organs revealed a higher level of ƒ¿ isomer in the fatty tissue of male and female rats, than in other organs. There was no significant accumulation of the ƒ¿ and ƒÀ isomers of endosulfan in the vital organs inspite of repeated exposure which seems to be the reason for the absence of a severe toxicological response in the rats. The lower doses of endosulfan, however, showed none of the toxicological effects in male (0.75 and 2.5 mg/kg/D) and female (0.25 and 0.75 mg/kg/D) rats.