Toxic substances produced by fungi or moulds on agricultural crops that may cause sickness in animals or humans that eat feed or food made from contaminated crops. There are between 300 and 400 known mycotoxins, but of most concern, based on toxicity and occurrence, are aflatoxin, vomitoxin, zearalenone, funonisin, T-2 toxin, and T-2-like toxins (trichothecenes). GIPSA currently measures for aflatoxin in all exports shipments of corn, and measures for aflatoxin and vomitoxin on a voluntary basis in domestic shipments.