Mycotoxins: what are they and how to prevent them


Mycotoxins: What are they and how to prevent them?

Even though it is not often asked what mycotoxins are or how they can be prevented, the toxins still remain detrimental to the wellbeing of humans and livestock alike. Mycotoxins are harmful and have been reported to cause serious illnesses such as cancer, and even death of animals. As such, they should prevented by every means possible.

What are Mycotoxins?

Mycotoxins are toxic organic compounds produced by Fungi. They are quite small with a unit size of about 0.1 micron which is significantly smaller than the human hair follicle1. In context, the latter is about 100 micron in size and can be likened to the thickness of a single sheet of paper.  This small size makes mycotoxins easily mobile and undetectable, except for when they exist in large quantities clustered on a single surface.

Sources of Mycotoxins

Mycotoxicosis is a condition that occurs from the consumption of mycotoxins from any source. The severity of the symptoms of this condition depends on several factors such as the amount of toxin consumed as well as the stretch of consumption time. Other factors include the affected person’s sex, age and pre-existing health condition such as the presence of other infectious diseases, deficiency in certain vitamins, and caloric deficit/deprivation2. Also, interactions with other toxins in the body may aggravate the effect of its consumption which can easily expose the body to conditions of acute malnutrition and diseases caused by other microorganisms other than fungi. Therefore, the following are sources of mycotoxins and channels through which mycotoxicosis can occur;

  1. Food: mycotoxins are most prolific on surfaces with moisture and as a result can be easily found growing on food at different points along the value-chain. It may appear before or after crops are harvested, during storage or after processing.
  2. Mushrooms: Asides food, the toxic organic compound are also present in some species of mushrooms, especially misidentified species. This can cause hallucinations, gastrointestinal upset, depression, brain or liver damage and subsequently death within few days of consumption; symptoms of a condition referred to as mushroom poisoning.
  3. Animals: feeding on the by-products of animals exposed to the toxin is also a channel through which humans and other animals can be exposed.

Notable symptoms of mycotoxicosis include;

  1. Abdominal pain, nausea, diarrhea
  2. Gastrointestinal upset
  3. Body weakness and tiredness
  4. Unstable body temperature
  5. Headaches
  6. Depression
  7. Frequent urination
  8. Unstable appetite
  9. Cough
  10. Body pains
  11. Unstable appetite
  12. Hallucination

These symptoms may subsequently lead to more complicated health challenges such as brain or liver damage, weakened immune system, loss of limbs, cardiac arrest, hemolysis, kidney failure, microbial diseases (caused by other microorganisms), DNA damage, cancer and death. Any of these may occur within a few days to few weeks of exposure.

Types of Mycotoxins

Although over 350 mycotoxins have been identified so far, all of which contain significant and varying amounts of toxins, the harmful organic compounds still differ in terms of structure and level of toxicity3. Not all mycotxins are lethal, and not all mycotoxins lead to severe, life-threatening health conditions. Of those identified, some of the commonest are aflatoxin which can be found growing on soils, or foods such as rice, wheat, groundnut, cotton, tumeric and ginger. Others include patulin produced by different fungi and found on rotten apples, Ochratoxin A which is produced mostly during storage of beans and some cereals, and fusarium fungi which can also be found on soils and cereals such as maize and oat. These mycotoxins are by-products of different fungi such as Fusarium verticilloides, Aspergillus flavus, Penicillium chrysogenum, Penicillium citrinum, Penicillium brevicompactum and many more.

How to Prevent Mycotoxins

The production of mycotoxins can be prevented through any of the following;

  1. Good agricultural practices: this may involve the cultivation of fungal resistant variety of crops. Other practices include crop rotation, cultivating of pathogen free seeds, effective management of crop residue, weed control, irrigation, application of fungicides, timely harvesting of crops, proper handling after harvest etc.
  2. Good manufacturing practices: the maintenance of good hygiene by employees and within the manufacturing area, training and re-training employees to ensure compliance with standards, and proper storage after manufacturing are some good manufacturing practices.
  3. Buying fresh food produce: this eliminates the possibility of consuming food that may have been contaminated under poor storage or manufacturing conditions.
  4. Adopting better storage practices: this involves reducing the moisture content of crop harvest before storage, and can be achieved through drying. Also, storage of food stuff under lower temperature and humidity eliminates the possibility of having moisture which supports the production of mycotoxins. Application of fungicides, preservatives and approved insecticides in healthy doses can also be adopted as a better storage practice.
  5. Removal/separation of contaminated produce: This will prevent the spread of the toxins to uninfected items.
  6. Destruction of contaminated produce: depending on the extent of contamination, in severe cases where separationof the contaminated produce from the whole harvest may not be feasible, it is best to destroy the entire batch.
  7. Detoxification or inactivation of ingested toxins: on consumption of mycotoxins, microbial enzymes can be ingested in the form of additives. These enzymes are able to convert the toxins to non-toxic metabolites which are not harmful to the body. This process is referred to as the detoxification or inactivation of toxins.
  8. Elimination of other conditions that support fungal growth

These measures indicate that there is no singular approach to preventing the exposure of humans and livestock to mycotoxins, and that prevention may occur at any point within the value-chain. This implies that various value-chain actors at different points of producing, supplying and consuming food have a responsibility to ensure that what is consumed is not exposed to the toxin. Farmers at the point of production, manufacturers and their employees at the point of processing and storage, suppliers at the point of  moving food from one point to another, and consumers, at the point of purchase or consumption. It is therefore imperative for value-chain actors to have a clear understanding of their roles and follow through accordingly.


  1. R & R (2019): Mold Restoration…Don’t forget the mycotoxins! An online blogpost by Julie Hurst. Retrieved from
  2. Bennett, J. & Klich, M. (2003). Mycotoxins. Clinical Microbiology Reviews. 16. 497-516. 10.1128/CMR.16.3.497-516.2003. Retrieved from
  3. Armendáriz, C.R., Fernández, Á.J.G., Gironés, M.C.L.R., & de la Torre, A.H. (2014): Mycotoxins. Pp. 424-427, ISBN 9780123864550. Retrieved from
  4. All About Feed (2016): Mycotoxin Deactivation with Natural Enzymes. Blogpost retrieved from

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