Subchronic Feeding Study of the Mycotoxin Fumonisin B1 in B6C3F1 Mice and Fischer 344 Rats

Fumonisin B1 (FB1) is a mycotoxin produced by Fusarium moniliforme,a common fungus which occurs naturally on corn, and other Fusariumspecies. FB1 and other fumonisins are now recognized as havingpotentially important animal and human health implications.However, few toxicological data are currently available. Maleand female B6C3F1 mice and Fischer 344 rats were fed diets containing0, 1, 3, 9, 27, or 81 ppm FB1 (98% purity) for 13 weeks. Nodifferences in behavior or appearance, body weight or food consumptionbetween control and FB1-fed groups were found. In mice, hepatopathyand altered serum chemical profiles indicative of hepatotoxicitywere found in females fed the 81 ppm diet. No adverse effectswere found in female mice fed 27 ppm FB1 or in male mice atany dietary level studied. In rats, nephrosis involving theouter medulla was found in males fed 9 ppm and, to a lesserdegree, in females fed 81 ppm FB1, while decreased kidney weightwas found in both sexes at dietary levels 9 ppm FB1. Althoughthe liver is a target organ of FB1 in rats, hepatotoxicity wasnot found in rats fed diets containing up to 81 ppm FB1 for90 days. Thus, FB1 was toxic to both species following subchronicoral exposure, although significant interspecies differencesin the no observed effect levels and organ-specific responseswere found.