TOXICITY OF ENDOSULFAN - DISTRIBUTION OF ALPHA-ISOMERS AND BETA-ISOMERS OF RACEMIC ENDOSULFAN FOLLOWING ORAL-ADMINISTRATION IN RATS

Endosulfan was administered orally (2.5 and 7.5 mg/kg) daily to male rats for 60 days. The distribution pattern of .alpha.- and .beta.-isomers was studied using GLC equipped with an electron capture detector. There was a significant increase in liver and lung weights. The testes weight was slightly decreased. No significant change in weights of other tissues was observed. At both dose levels, the concentration of .alpha.-isomer was highest in kidney (574 and 1655 ng/g, respectively), followed by lung, ventral prostate, spleen, testes and brain. In the seminal vesicle, epididymis, heart and liver, the concentration of .beta.-isomer was higher. The results of the study indicated a differential ability to accumulate the 2 isomers of endosulfan which may help to explain the difference in the toxic potential of the .alpha.- and .beta.-isomers.