NATURAL COOCCURRENCE OF FUMONISINS AND ZEARALENONE IN CEREALS AND CEREAL-BASED FOODS FROM EASTERN AND SOUTHERN AFRICA

The natural co-occurrence of fumonisin B1 (FB1), fumonisin B2 (FB2), f umonisin B3 (FB3), and zearalenone was investigated in 40 randomly sel ected cereals and cereal-based commodities collected in 1994 from Bots wana, Kenya, Malawi, Mozambique, South Africa, Tanzania, Uganda, Zambi a, and Zimbabwe. FB1 was detected in 37 of the samples (92.5%) at conc entrations ranging from 20 to 1910 ng/g, while total fumonisin (FB1 FB2 + FB3) concentrations in the same samples ranged from 20 to 2735 n g/g. The highest total fumonisin levels were detected in maize kernels from Zimbabwe (2735 ng/g). In contrast to the high incidence of fumon isins (92.5%), zearalenone was detected in only five samples (12.5%) a t concentrations ranging from 40 to 400 ng/g. Linear regression analys is showed no correlation between the occurrence of fumonisins and zear alenone in the samples tested. Although limited in sample numbers, thi s survey ranks the fumonisins as major contaminants of cereals and cer eal-based foods in Eastern and Southern Africa.