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authorities. Radical solutions that take into account the needs and conditions of developing countries are urgently needed. Mycotoxins are chemical substances naturally produced by a modest number of species of fungi that grow on crops either in the field or in storage. In sub-Saharan Africa, two important crops are commonly contaminated: maize and groundnuts – major food crops and cash earners for millions of small-scale farmers. The best known of these chemical substances is aflatoxin, produced by Aspergillus flavus, found in both maize and groundnuts. More recently, fumonisin, produced by Fusarium verticilliodes, was discovered in maize in southern Africa. Exposure to these mycotoxins may occur simultaneously. In animal studies, the effect of aflatoxin is promoted by the concurrent presence of fumonisin. In humans, interaction between the two toxins is not understood. Multiple health risks For centuries, farmers in Central America reduced their exposure to aflatoxin, knowingly or unknowingly, by treating their maize with lye. Unfortunately, this procedure did not accompany maize on its eventual journey to Asia and Africa and is in any case not feasible where water is in short supply. The exposure of people and animals to aflatoxin and fumonisin presents multiple health risks, both proven and probable (Cardwell, 1999). Aflatoxin, which damages DNA, is the most potent chemical liver carcinogen known. Many people in developing countries are infected by hepatitis B and C which are probably even more potent liver carcinogens. The combination of the two agents, aflatoxin with hepatitis B and C, is synergistic, raising more than tenfold the risk of liver cancer compared with each attacking alone. Acute aflatoxicosis occurs in poultry, swine, cattle and people. At lower but chronic exposures, aflatoxin may damage the liver, lower appetite, promote diarrhoea, inhibit growth and suppress the immune system. Recent studies conducted in West Africa are shedding light on the potential for aflatoxin-induced immune suppression in humans. Fumonisin interferes with critical lipid pathways affecting cell function including the transport of critical vitamins such as The combination of aflatoxin with hepatitis B and C is synergistic, raising more than tenfold the risk of liver cancer compared with each agent attacking alone