Distribution and biliary excretion of carbaryl, dieldrin and paraquat in rats: effect of diets.

Carbaryl and dieldrin were accumulated mostly in the liver, and paraquat was accumulated in the kidney of normal diet (casein 24.5%) rats at 1 hr after the oral administration. At 5 hr after the administration, the concentration of carbaryl in liver or fat, and that of paraquat in kidney were markedly decreased. However, dieldrin in liver, kidney, lung, fat or others was signficantly increased at the same period. The absorption of paraquat from gastrointestinal tract was the least among the chemicals used. Biliary excretion of carbaryl was the highest and that of paraquat was the least by 5 hr after intravenous administration. The excretion ratio was about 100: 10: 1 for carbaryl, dieldrin and paraquat in normal diet rats. Biliary excretion of these chemicals was higher in high protein diet (casein 45%) rats and retention of the chemicals in tissue was higher in low protein diet (casein 5%) rats.