Aflatoxins isolated by immunoaffinity chromatography from foods consumed in the Gambia, West Africa

An aflatoxin‐specific, monoclonal antibody‐based immunoaffinity chromatography method has been developed for the rapid isolation of aflatoxins from human foods. Aflatoxins were isolated by immunoaffinity chromatography from a variety of cooked foods, including maize, rice, millets, groundnut sauces, and leaf sauces, collected in The Gambia, West Africa. The aflatoxins were measured by direct fluorescence or high‐pressure liquid chromatography. The highest levels were found for groundnut sauces, mean 162 ppb (range 18 to 943 ppb) for 18 positive samples, but aflatoxins were found in other foods; e.g., maize, mean 9.7 ppb (range 2 to 35 ppb) for nine positive samples. The food analysis results were used with records of the amounts of cooked food to estimate a mean daily intake for an individual of the order of 3.5 μg of aflatoxins per day. This approach for exposure assessment is considered in relation to other biomarkers of aflatoxin exposure using biological fluids. © 1992 Wiley‐Liss, Inc.