Mycotoxins are chemical substances naturally produced by fungi that contaminate crops, either during the cropping season or in storage. Worldwide, substantial quantities of food grains are affected by mycotoxins each year: maize 16 million tons, rice 12 million t, groundnut 1.8 million tons, sorghum and millet 378,000 t, copra 3.7 million t, soybean 2.3 million tons.

In the semi-arid tropics a number of crops are often contaminated by mycotoxins – groundnut, maize, cottonseed, sorghum, millet, rice, Brazil nuts, pecans, pistachio nuts, spices (particularly chillies), walnuts… and products made from these crops.

Two important mycotoxins are aflatoxin, produced by Aspergillus flavus and A. parasiticus; and fumonisin produced by Fusarium verticilliodes. Both are commonly found in legumes and cereal crops. Aflatoxins are potent carcinogenic and immunosuppressive agents. Aflatoxin contamination of groundnut and maize has become a global problem due to the effects on human and animal health, and the negative impact on commodity trade. Malnutrition increases disease prevalence and further reduces the ability of the human body to cope with mycotoxin exposure.


Aspergillus flavus, which causes
aflatoxin contamination
When animals consume aflatoxin-contaminated feed they produce milk that is in turn contaminated by aflatoxin M1. Aflatoxin M1 is a metabolite of aflatoxin B, and is known to be carcinogenic, producing tumors and liver cancer in test animals. The legal limit in milk is 0.05 parts per billion (ppb) for aflatoxin M1.

Many importing countries have set strict quality standards to control the health risk from mycotoxin contamination. However, most poor, small-scale farmers in the semi-arid tropics cannot meet these standards.

In 1997, the European Commission proposed maximum limits for aflatoxins in certain foodstuffs. The standard ranged from 4 ppb in cereals, edible nuts, and dried fruit, to 10 ppb for nuts that are subject to further processing. Recent studies have found that implementation of the new EC standards on aflatoxin will adversely affect third world exports of cereals, dried fruits, and edible nuts to Europe.

Mycotoxin-contaminated products cause significant economic and trade problems at almost every stage of production and marketing. Many of our crops are affected by these mycotoxins, and standards are becoming progressively stricter. It is therefore critical to undertake research that will help small-scale farmers to meet international quality standards and continue to profitably market their crops.

The proposed research program aims to develop inexpensive, practical methods to reduce or eliminate the levels of aflatoxin in groundnut and its products, and to disseminate information on the dangers of aflatoxin. Ultimately, the goal is to help small-scale farmers in the semi-arid tropics produce aflatoxin-free food and feed products. This work will involve several partners - ICRISAT, government health agencies, universities, national research institutes, NGOs, and the private sector.

A number of benefits are expected. The development of safety measures will help improve the health of the rural poor, particularly women and children. It will also improve the marketability (and prices) of crops, and thus farmers’ incomes.

The specific components of this research - and the role of each partner - were developed on the basis of current knowledge (and knowledge gaps) on mycotoxin control, and the comparative advantage of each partner. Components of the research work plan include:


• Collect data on toxicology.

• Large-scale risk assessment of mycotoxins in various commodities, and the effect on human health.

• Help establish a system of quality control and safety standards, and appropriate food safety legislation.

• Reduce the effect of mycotoxins on human and animal health by developing and promoting appropriate crop management methods.