Mycotoxins are poisonous substances produced by certain molds found primarily in grain and nut crops, but are also known to be on celery, grape juice, apples, and other produce.  There are many of them and scientists are continually discovering new ones.  The Food and Agriculture Organization (FAO) of the United Nations estimates that 25% of the world's food crops are affected by mycotoxins, of which the most notorious are aflatoxins.

Aflatoxins are considered unavoidable contaminants of food and feed, even where good manufacturing practices have been followed.

This report is a Fact Sheet prepared by the USDA's Food Safety and Inspection Service.