The Problem

Mycotoxins

Why are they important?

Mouldy and clean "natural" coffee

It is likely that mycotoxins have plagued mankind since the beginning of organised crop production. We now know that St Anthony's Fire (ergotism) was caused by the consumption of rye contaminated with 'ergot alkaloids', produced by the mould Claviceps purpurea , and that it reached epidemic proportions in many parts of Europe in the tenth century.

Mycotoxins occur in a wide variety of foods and feeds and have been implicated in a range of human and animal diseases. Exposure to mycotoxins can produce both acute and chronic toxicities ranging from death to deleterious effects upon the central nervous, cardiovascular and pulmonary systems, and upon the alimentary tract. Mycotoxins may also be carcinogenic, mutagenic, teratogenic and immunosuppressive. The ability of some mycotoxins to compromise the immune response and, consequently, to reduce resistance to infectious disease is now widely considered to be the most important effect of mycotoxins, particularly in developing countries. Diseases caused by mycotoxins are called 'mycotoxicoses'.

The deaths of thousands of people in Siberia due to the development of Fusarium toxins in overwintered grain during WWII led to the discovery of the trichothecenes. The first recognition of mycotoxin importance in public health can be traced to the post-war period in Japan and the USSR. Suspect rice supplies, despite a severe scarcity of rice in Japan, were impounded and intense research into the mycotoxins of rice was initiated. Mycotoxins became a public health priority in the West when, in the 1960s, widespread deaths of turkey poults in the U.K. led to the discovery of aflatoxin and, later, to it's potent carcinogenic properties. Although cases of acute human mycotoxicosis continue to be reported, it is chronic exposure to mycotoxins, particularly for children, that is of much more widespread public health concern.

The mycotoxins attract world-wide attention because of the significant economic losses associated with their impact on human health, animal productivity and both domestic and international trade. According to FAO estimates, world losses of foodstuffs due to mycotoxins are in the range of 1000 million tonnes per year. In developing countries, where food staples (e.g. maize and groundnuts) are susceptible to contamination, it is likely that significant additional losses will occur amongst the human population because of morbidity and premature death associated with the consumption of mycotoxins.

As mycotoxins are naturally occurring contaminants produced by fungi that are ubiquitous man has always been exposed to these compounds in his diet. Most mycotoxins are chemically stable so they tend to survive storage and processing even when cooked to quite high temperatures. This makes it important to avoid the conditions that lead to mycotoxin formation as far as possible. It is not possible to eliminate them completely from the food supply, but by promoting good hygiene practices throughout the food chain, with emphasis on those points of the chain where there is greatest risk of this food hazard developing, the level of mycotoxins in foods can be reduced to tolerable levels.

Many countries have legislated maximum levels of certain myctoxins in selected foods to ensure an acceptable level of protection for their citizens against the harmful effects of chronic exposure to these contaminants (see the International Portal on Food Safety, Animal and Plant Health).