Biotransformation as a Determinant of Species Susceptibility to Aflatoxin B1: In Vitro Studies in Rats, Mouse, Monkey, and Human Liver

  • David L. Eaton
  • Howard Ramsdell
  • David H. Monroe

Abstract

Susceptibility to the toxic and carcinogenic effects of aflatoxin B1 (AFB1) varies markedly between species.3,4,47,48,49,62 The duck, rabbit, pig, and trout are highly susceptible to the acute toxic effects of AFB (LD50 0.3-0.8 mg/kg) and the monkey is moderately susceptible (LD50 ∼2.0 mg/kg). The rat, mouse, and hamster are generally considered to be relatively resistant to the acute effects of AFB, though some discrepancies in the published LD50’s exist, possibly due to strain, sex, and/or age differences. The LD50 for rats has been reported to be between 1.0 and 17.9 mg/kg while published values for the mouse range from 9.0 to 60 mg/kg. The duck, trout, and rat are highly susceptible to the carcinogenic effects of AFB, while the mouse and hamster are relatively resistant. Lifetime dietary exposure to as little as 15 ppb has induced hepatocellular carcinoma in rats, and 100% incidence of liver cancer was obtained with 100 ppb of AFB for a lifetime.64 Numerous other studies have demonstrated similarly potent carcinogenicity in rats.60,63 In contrast to the rat, Swiss-Webster mice given a diet containing 150,000 ppb of an AFB+AFG mixture failed to develop any liver tumors.64 However, liver tumors were obtained in C57BLxC3H mice injected with 1.25 mg/kg three times during the first 10 days after birth, demonstrating the importance of age-dependent factors in carcinogenic suscep- bility.55

Keywords

Glutathione Cytosol Macromolecule Cyclohexene Butylate 

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Copyright information

© Plenum Press, New York 1990

Authors and Affiliations

  • David L. Eaton
    • 1
  • Howard Ramsdell
    • 1
  • David H. Monroe
    • 1
  1. 1.Department of Environmental Health and Institute for Environment StudiesUniversity of WashingtonSeattleUSA

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