Levels and daily intake estimates of aflatoxin B1 and fumonisin B1 in maize consumed by rural households in Shamva and Makoni districts of Zimbabwe

Abstract

Levels of aflatoxin B1 and fumonisin B1 in maize samples collected from rural households in Shamva and Makoni districts of Zimbabwe were determined. Aflatoxin B1 was determined using high performance liquid chramotography with fluorescence detection and post-column derivatisation. Aflatoxin B1 was detected in 80 of the 388 samples analysed at levels ranging between 0.57 and 26.6 μg/kg (median, 3.21 μg/kg). Of the samples containing aflatoxin B1, 18 exceeded the Zimbabwean limit for aflatoxins (5 μg/kg). Fumonisin B1 was determined using EuroProxima™ ELISA kits. All samples analysed contained levels of fumonisin B1 ranging between 10.43 μg/kg and 432.32 μg/kg (median, 292.15 μg/kg) and 13.84 μg/kg to 606.64 μg/kg (median, 360.18 μg/kg) for Shamva and Makoni districts respectively. In Shamva district the probable daily intake of fumonisin B1 ranged between 0.14 and 5.76 μg/kg body weight/day and in Makoni district the probable daily intake of fumonisin B1 ranged between 0.18 and 8.092 μg/kg body weight/day. In Shamva district fumonisin B1 and aflatoxin B1 were found together in 36 out of 166 samples analysed. In Makoni district fumonisin B1 and aflatoxin B1 were found together in 44 out of 222 samples analysed. Of the 80 samples that contained fumonisin B1 and aflatoxin B1, 18 samples contained levels of aflatoxin B1 above the national maximum regulatory limit.