The term 'mycotoxin' is usually reserved for the toxic chemical products formed by a few fungal species that readily colonise crops in the field or after harvest and thus pose a potential threat to human and animal health through the ingestion of food products prepared from these commodities
Each mycotoxin is produced by one or more very specific fungal species. In some cases one species can form more than one mycotoxin.
Mycotoxins cause a diverse range of toxic effects because their chemical structures are very different from each other. Acute effects require that high amounts are present when eaten so that such incidents are usually restricted to the less developed parts of world where resources for control are limited, or to livestock. Chronic effects are of concern for the long-term health of the human population and are important when present in much lower amounts. Some of the most common mycotoxins are carcinogenic, genotoxic, or may target the kidney, liver or immune system.
National and International Organisations are constantly evaluating the risk that such mycotoxins pose to man. For some mycotoxins this has resulted in statutory or guideline maximum permissible limits. Many countries now have legal limits for aflatoxins that are the most widespread and toxic mycotoxins, although these values are by no means uniform