T-2 toxin is an emetic trichothecene mycotoxin produced by Fusarium molds. This compound causes feed refusal, emesis and lesions in the gastrointestinal tract of livestock, poultry and man. Studies in our laboratory have indicated that the feeding of high fibre diets, non-nutritive mineral additives and high fat diets can largely overcome feed refusal caused when T-2 toxin is fed to rats. Subsequent experiments were designed to determine the mechanism by which such diets exert this effect. Rats were fed for two weeks diets containing varying levels of alfalfa meal, bentonite or corn oil in a casein-based semi-purified diet. Rats were then orally dosed with [3H] T-2 toxin and urine and feces were collected for 21 hours after which all animals were killed and tissues excised. Diet had no significant effect on the fraction dose of 3H excreted in the urine. Significant increases in fecal excretion of 3H were seen, however, with all test diets. Only high fat diets reduced hepatic residues of 3H while alfalfa had a similar effect in kidney and both alfalfa and bentonite lowered muscle residues. It was concluded that such dietary treatments overcome T-2 toxicosis mainly by promoting fecal excretion of toxin thereby reducing absorption and biological half-life.