Aflatoxin and Trichothecene Toxins: Skin Tumor Induction and Synergistic Acute Toxicity in White Mice

Abstract

Toxic interactions of 3 naturally occurring mycotoxins were examined by the mouse skin tumor test and acute toxicity trials. Aflatoxin B₁ (B₁) functioned as a tumor-initiating substance; a single 25-µg dose applied before croton oil as promoter caused papilloma formation on more than half the test animals. Neither Fusarium toxin, T-2 toxin (T-2), or diacetoxyscirpenol served as initiating agents. These 2 mycotoxins acted as weak promoter substances on 7,12-dimethylbenz[a]-anthracene (DMBA)-initiated mouse skin cells but not on mice treated with B₁ as initiator. Either DMBA or B₁ initiation followed by T-2 promotion (25 µg/dose) caused extensive skin damage and subsequent tolerance of the treated skin to elevated doses of T-2. In acute toxicity trials, combinations of B₁ and T-2 produced a synergistic lethal response.