Dietary Exposure to Genotoxic Mycotoxins in Maize ( Zea mays L.) Grains Consumed in Cotonou Municipality (Benin): the Case of Aflatoxin B1

Aflatoxin B1 (AFB1) is a genotoxic and carcinogenic mycotoxin produced mainly by Aspergillus flavus , A. parasiticus and A. nomius , moulds that contaminate cereals, including maize ( Zea mays L.), which is widely consumed in Benin. The aim of this study was to assess the level of dietary exposure to AFB1 in maize sold and consumed in the municipality of Cotonou. Thirty-eight samples of maize grain collected from markets in Cotonou were analysed by high-performance liquid chromatography with fluorescence detection. AFB1 dietary exposure was estimated based on the measured concentrations and maize consumption data. The results of the analyses show a wide range of AFB1 contamination levels in the samples, ranging from 1 to 104 µg/kg. Of the samples analysed, 81.57% had levels exceeding the regulatory limit set for AFB1. Average maize consumption was estimated at 136.22 kg/person/year, or 0.37 kg/person/day. AFB1 daily exposure was estimated to 0.07 µg/kg body weight/day. These results reveal high levels of AFB1 contamination in maize in the municipality of Cotonou and highlight chronic dietary exposure that may pose a health risk to consumers. Strengthening measures for monitoring, quality control and post-harvest management of maize appears necessary in order to reduce the population’s exposure to this mycotoxin.