Metabolic Epoxidation of Aflatoxin B1 and its Metabolites: Patterns of DNA Adduct Formation and Removal in Relation to Biological Effects

  • John M. Essigmann
  • Robert G. Croy
  • Richard A. Bennett
  • Gerald N. Wogan
Part of the NATO Advanced Study Institutes Series book series (NSSA, volume 52)


Aflatoxin B1 (AFB1) is the most toxic and carcinogenic member of a family of difuranocoumarins produced as secondary metabolites by strains of Aspergillus flavus and related fungi1. Exposure to aflatoxin is a public health hazard in technologically developing areas of the world, where AFB1-producing fungi are distributed widely and where food production and storage conditions are conducive to mold spoilage and consequent mycotoxin production. In most animals, the main target for the biological effects of AFB1 is the liver, although the relative sensitivity of different animal species varies markedly; the rat, rainbow trout and duck are highly sensitive whereas the mouse is resistant. The liver is also apparently a target in humans, in that a high incidence of hepatocellular carcinoma has been observed in chronically exposed populations2. Additional factors may act in concert in initiating the putative carcinogenic effects of AFB1 in humans; these include abnormal nutritional status or concomitant pathological conditions such as viral hepatitis.


Imidazole Ring Major Adduct Urinary Compound Sensitive Analytical Methodology Adduct Pattern 
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Copyright information

© Plenum Press, New York 1982

Authors and Affiliations

  • John M. Essigmann
    • 1
  • Robert G. Croy
    • 1
  • Richard A. Bennett
    • 1
  • Gerald N. Wogan
    • 1
  1. 1.Laboratory of Toxicology, Department of Nutrition and Food ScienceMassachusetts Institute of TechnologyCambridgeUSA

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