Many food crops can be infected by fungi and moulds which produce toxic compounds that are dangerous to humans after consumption. These so-called mycotoxins come in different chemical forms with a range of effects, from poisoning the kidneys and liver to causing vomiting and gastrointestinal upsets. Some mycotoxins are also harmful to livestock, so their presence in foodstuffs is to be avoided at all costs.
http://www.spectroscopynow.com/details/ezine/159652e8090/Mouldy-mycotoxins-Imaging-distributions-in-food.html?&tzcheck=1
Mouldy mycotoxins: Imaging distributions in food