Mycotoxins are poisonous substances produced by fungi or mold. They can be toxic for humans when they are eaten, absorbed into the skin, or inhaled. Mycotoxins are naturally occurring toxins produced by certain moulds and can be found in food. The moulds grow on a variety of different crops and foodstuffs including cereals, nuts, spices, dried fruits, apples and coffee beans, often under warm and humid conditions.