Aflatoxin determination in commonly consumed foods in Tunisia.

Background: To investigate natural aflatoxin occurrence, a total of 180 samples of different foods widely consumed in Tunisia were analysed by an in-house-validated high-performance liquid chromatography method including affinity column clean-up and post-column bromination techniques.

Results: The method used appeared to be rapid, selective and reproducible, and its performances were established. Detection limits were 0.05 ng g(-1) for aflatoxin B1 and 0.025 ng g(-1) for aflatoxins B2, G1 and G2. Aflatoxins were detected in all investigated commodities except rice, with an overall contamination frequency of 34.4% and concentrations ranging from 0.1 to 40.6 ng g(-1). Aflatoxin B1 was found in all contaminated samples. Sorghum, spices and nuts were most contaminated.

Conclusion: This study has provided an effective analytical method for the reliable determination of aflatoxins in food samples. Over one-third of the samples investigated were contaminated with aflatoxins. Sorghum, spices and nuts were most contaminated, whereas rice showed no contamination.