Is a saprotrophic and pathogenic fungus which produce aflatoxin. Aflatoxin is a contaminant of nuts and grain. It is both a toxin and a carcinogen. A. flavus infections can occur while hosts are still in the field (preharvest), but often show no symptoms (dormancy) until postharvest storage and/or transport. In addition to causing preharvest and postharvest infections, many strains produce significant quantities of toxic compounds known as mycotoxins, which, when consumed, are toxic to mammals. Also is an opportunistic human and animal pathogen, causing aspergillosis in immunocompromised individuals.