TOXICITY OF FUMONISIN B-1 TO B6C3F(1) MICE - A 14-DAY GAVAGE STUDY

Fumonisin B-1 (FB1) is a fungal toxin produced by members of the genus Fusarium. Ingestion of FB1 causes species-specific neurotoxic, nephro toxic, hepatotoxic and pulmonary effects. The clinical, haematological and pathological responses of adult male and female B6C3F(1) mice to FBI were assessed following 14 daily gavage doses ranging from 1 to 75 mg FB1/kg body weight/day. There were no consistent sex-related chang es. Although all responses were modest, the most notable effects of FB 1 were on the liver, bone marrow, adrenals and kidneys. In the liver, hepatocellular single cell necrosis, mitosis and anisokaryosis were ob served, accompanied by elevated serum ALT. In the kidneys, minor histo pathological changes were confined to female mice, while mild decrease s in ion transport and increases in blood urea nitrogen were seen only in males. Small changes in glutathione levels were observed in the ki dneys and livers of male mice. Adrenal cortical cell vacuolation was o bserved at 15 mg FB1/kg and higher in females and from 35 mg FB1/kg in males. Serum cholesterol was elevated in both male and female mice, p ossibly due to FB1-induced changes in lipid metabolism in the liver an d adrenals. Although bone marrow cell numbers were unchanged, increase s in vacuolated myeloid cells and lymphocytes were observed in female mice. In general, the degree of changes observed indicate that mice ar e not as sensitive a model of FB1 toxicity as rats. (C) 1997 Elsevier Science Ltd. All rights reserved.