Determination of multi-mycotoxin occurrence in cereals, nuts and their products in Cameroon by liquid chromatography tandem mass spectrometry (LC-MS/MS)

This is a report on multi-mycotoxin occurrence in staple food commodities from Cameroon. Samples, including maize and maize-based products, nuts and nut-based products as well as beer, beverage and soybean were analysed for 320 toxic and potentially toxic fungal secondary metabolites by liquid chromatography electrospray ionization tandem mass spectrometry (LC-ESI-MS/MS). A total of 69 metabolites were detected in all studied commodities. These metabolites included all mycotoxins regulated in the EU with aflatoxin B1 (AFB1) and fumonisin B1 (FB1) as the most frequently recovered. Aflatoxin B1 was detected in soybean, kuru-kuru and dagwa at frequencies of 100%, 97% (groundnut); 93% (groundnut soup); 36% (maize-beer); and 30% (maize), while groundnuts and its by-product (kuru-kuru) were the most concentrated sources of the toxin (overall mean 47-52 μg kg−1, range < LOQ-210 μg kg−1). Fumonisin B1 was present in all commodities tested with the exception of groundnut soup and groundnut in which the incidences of FB1 were 73 and 51%, respectively, meanwhile the highest levels (mean 508 μg kg−1; range 2-2313 μg kg−1) were found in maize. As far as geographical variation was concern, mean values of aflatoxin G1 (AFG1) and G2 (AFG2) in groundnuts from the western highlands (Bamenda) were significantly higher (p < 0.05) than those from the tropical south (Yaounde), while there was no significant difference (p > 0.05) in mean values of AFB1, aflatoxin B2 (AFB2) and the FBs across regions. Amongst all regulated mycotoxins recovered from all studied food categories reported in this study, total AF levels exceeded the maximum tolerable limits of the European Commission Regulations. The widespread nature and high levels of multiple mycotoxins occurring in the most concentrated food sources suggest proportionately high exposure levels that could be accompanied by severe health implications.