Biliary excretion of the mycotoxin fumonisin B1 in rats

The biliary excretion of the mycotoxin fumonisin B1 (FB1), produced by the fungus Fusarium moniliforme Sheldon, has been measured in male Wistar rats. After ip injection of a solution of FB1 (7.5 mg/kg body weight), 67% of the applied dose was recovered in bile over a 24-hr period, 88% of this recovery being excreted in the first 4 hr after dosing. In contrast to these results, a similar dose of FB1 given by gavage resulted in only 0.2% recovery of the toxin in bile over a 24-hr period. Hence, although these results show that biliary excretion is a major route of elimination of FB1 from the circulation, only small amounts of the toxin appeared to be absorbed from the gut in rats.