The worldwide contamination of foods and feeds with mycotoxins is a significant problem. Mycotoxins are
secondary metabolites of molds that have adverse effects on humans, animals, and crops that result in illnesses and
economic losses. Aflatoxins, ochratoxins, trichothecenes, zearelenone, fumonisins, tremorgenic toxins, and ergot
alkaloids are the mycotoxins of greatest agro-economic importance. Some molds are capable of producing more than
one mycotoxin and some mycotoxins are produced by more than one fungal species. Often more than one mycotoxin
is found on a contaminated substrate. Factors influencing the presence of mycotoxins in foods or feeds include
environmental conditions related to storage that can be controlled. Other extrinsic factors such as climate or intrinsic
factors such as fungal strain specificity, strain variation, and instability of toxigenic properties are more difficult to
control. Mycotoxins have various acute and chronic effects on humans and animals (especially monogastrics)
depending on species and susceptibility of an animal within a species. Ruminants have, however, generally been more
resistant to the adverse effects of mycotoxins. This is because the rumen microbiota is capable of degrading
mycotoxins. The economic impact of mycotoxins include loss of human and animal life, increased health care and
veterinary care costs, reduced livestock production, disposal of contaminated foods and feeds, and investment in
research and applications to reduce severity of the mycotoxin problem. Although efforts have continued internationally
to set guidelines to control mycotoxins, practical measures have not been adequately implemented. © 2001
Elsevier Science Ireland Ltd. All rights reserved.