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cob.gif (5877 bytes)A Toxic Substance - Aflatoxin

Some fungi produce toxins (mycotoxins) that can cause sickness and even death in both animals and humans. Mycotoxins have been a health  problem for a long time. The Chinese knew and wrote about mycotoxins thousands of years ago.

What are mycotoxins?

Mycotoxins are the products of fungal growth. Learning how fungi produce mycotoxins and which fungi produce mycotoxins could be a first step in helping prevent exposure to these harmful poisons.

How are we exposed to mycotoxins?

People get exposed to mycotoxins from the foods they eat. Fungi can grow on grain and food at any stage, from pre-harvest to the time it is eaten, without being detected. The fungi can leave behind these mycotoxins, which we cannot see, and mycotoxins grow as the feed is being processed for animals and humans to eat. It is hard to know if a food contains these mycotoxins because we can't taste them or, sometimes, even see them. No level of mycotoxins has been shown to be completely safe.

Of the many mycotoxins that occur as natural products in foods, aflatoxins are the only ones that are currently regulated in the United States. We know that these aflatoxins are "unavoidable contaminants" in our food.  So, the Federal Drug Administration (FDA) regulates aflatoxins by setting a limit on how much contamination is allowed.  For example, if corn has more than 20 parts per billion of aflatoxin, then it is considered unsafe and cannot be sold to be processed into food.  Aflatoxins are found in grains such as corn and are especially a problem during extended periods of drought.

Four types of the aflatoxins have been reported to occur naturally and one, aflatoxin B1, is the strongest toxin and can cause cancer. The young of all species of animals are most affected by aflatoxins and can have a wide range of problems following ingestion, including digestive distress, anemia, jaundice, reduced appetite and decreased growth

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