TOXICITY OF FUMONISIN B-1 ADMINISTERED INTRAPERITONEALLY TO MALE SPRAGUE-DAWLEY RATS

The toxicity of purified fumonisin B-1 (FB1) administered ip was exami ned in male Sprague-Dawley rats. FB1 was injected at 7.5 or 10 mg/kg b ody weight/day for 4 consecutive days. This resulted in significant re ductions in body weight, food consumption and faeces production. Polyu ria without a compensatory increase in water consumption was observed in treated rats. Erythrocytosis, elevated haematocrits and haemoglobin levels were attributed to dehydration. Nephrotoxicity in treated rats was evident by clinical changes including elevated blood urea nitroge n and by subtle changes in kidney morphology. Histopathology and serum biochemistry also indicated that the liver was an important target or gan in FB1-treated rats. A small increase in liver glutathione concent ration was also evident in rats receiving 10 mg FB1/kg body weight. Ef fects on the immune system included reduced thymus weight, disseminate d thymic necrosis and consistently elevated serum immunoglobulin M lev els. Circulating phagocytic cell numbers were elevated in treated rats , probably owing to tissue damage associated with ip dosing. The liver and kidneys appear to be target organs of FB1 in Sprague-Dawley rats.