Survey of occurrence levels of Aflatoxins in selected locally processed cereal-based foods for human consumption from Ghana

Fifty cereal-based products intended for infants and young children were purchased at retail level across Greater Accra Region in Accra Metropolis from June-September 2013. The samples included rice-based, corn-based, wheat-based, oat-based, millet-based, legume-based and mixed grain. Extraction procedure involving solvent mixture of acetonitrile-water followed by immunoaffinity column clean-up step and HPLC with fluorescence detection and post-column derivatization (Kobra cell system) were used. Of the processed cereal-based food samples tested, 72% were contaminated with all four types of Aflatoxin, that is, 0.18-23.27 ng g−1 for Aflatoxin B1, from 0.08 to 2.62 ng g−1 for B2, from 0.07 to 6.18 ng g−1 for G1, and from 0.25 to 3.25 ng g−1 for G2. Total Aflatoxins (total AF) also ranged from 0.18 ± 0.02-25.93 ± 0.29 μgkg-1. Overall, the mean Aflatoxin values recorded in the rice-based, corn-based, wheat-based, millet-based, legume-based and mixed grain samples were 0.59 ± 0.02, 3.58 ± 0.02, 3.46 ± 0.11, 1.49 ± 0.02, 3.29 ± 0.12 and 8.29 ± 0.13 respectively. The results showed that 96% of the processed foods intended for infants contained AFB1 levels higher than the European Union permissible limits of 0.1 μg·kg-1 whilst 52% of the cereal-based foods exceeded the EU maximum limit of 2 μg/kg for AFB1 and 4 μg/kg for total Aflatoxins.