Mycotoxins

Contents

  1. Introduction
  2. Toxic Effects of Mycotoxins
  3. Mycotoxicosis Outbreaks
  4. Mycotoxin Occurrence in Foods
  5. Routes of Contamination
  6. Metabolism of Mycotoxins in Humans
  7. Aflatoxin
  8. Control Measures

1. Introduction to Mycotoxins

Following on from the white paper on chemical hazards, this paper takes a closer look at mycotoxins. Mycotoxins are a chemically diverse range of secondary metabolites (i.e. have no role in formal metabolism) and are produced by various fungal species especially Aspergillus, Fusarium, Penicillium. They are toxic to humans and most are chemically stable and survive prolonged heat processing. Mycotoxins are responsible of outbreaks and fatalities across the world every year. Deaths have been associated with ergotism, Alimentary Toxic Aleukia (ATA), stachybotryotoxicosis and aflatoxicosis.

2. Toxic Effects of Mycotoxins

The toxic effects of mycotoxins can be significant and varied depending on the toxin, dose, host and food matrix involved. These effects include:

  • Carcinogenicity (cancer causing) especially in the liver
  • Hepatotoxocoty (liver damage)
  • Mutagenicity (changes to DNA)
  • Other toxic effects include kidney disease, immumo-suppression and disturbance to the nervous and hormone systems

In order to define a toxin as a mycotoxin the following criteria must be met:

  • Cause disease in humans and animals
  • Occur in nature and be produced by a fungus
  • Cause acute or chronic toxic effects i.e. acute in high doses and carcinogenic in subclinical doses over long periods

3. Mycotoxicosis Outbreaks

Mycotoxicosis is poisoning caused by the ingestion of a mycotoxin. It results in specific symptoms and other adverse effects. Mycotoxicosis is not transmissible and drug or antibiotic therapies have little or no effect on the disease. Outbreaks tend to be seasonal depending on the consumption of particular foodstuffs during the year. The degree of toxicity is often influenced by age, gender and nutritional status of the host.