ABSTRACT
AF L A T O X I N S are extremely potent naturally occurring carcinogens that are found in feed for livestock as well as in food for human consumption. The two fungi, Aspergillus flavus and A. parasiticus, that most commonly produce aflatoxins do so on a number of substrates; but preharvest aflatoxin contamination is most serious on corn, peanuts, cottonseed, and tree nuts. Aspergillus flavus appears to be the primary aflatoxin-producing fungus on these commodities, although A. parasiticus also occurs frequently on peanuts (Payne, 1992). Both fungi produce a family of related aflatoxins (Bhatnagar et al., 1991a); the most prevalent aflatoxins produced by Aspergillus flavus are Bj and B 2 (Figure 10.1). In addition to B] and B 2 , A. parasiticus produces two additional aflatoxins, Gj and G 2. Bj is the most carcinogenic of the aflatoxins as well as the most abundant, and thus receives the most attention in mammalian toxicology (Bhatnagar et al., 1992).
