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Last Edited: 6/1/2001

What are mycotoxins?

While they are growing, some molds produce metabolic products that discourage or prevent bacteria or other fungi from growing in the same area. When those metabolic products also cause health problems in animals or humans, they are called mycotoxins (myco = fungal origin). Thus, mycotoxins are natural products from molds that may cause a toxic response in vertebrates when small amounts are eaten, inhaled or touched. Molds that are capable of generating toxins (called "toxigenic mold") do not always produce them in every situation. Scientists believe that certain very specific conditions must be present for a toxigenic mold to actually produce toxins, such as the right combination of temperature, moisture, type of material the mold is growing on and, perhaps, competition from other microorganisms.