Prevalence of aflatoxin along processing points of locally made complementary food formulae in northern Uganda: Safety and children's exposure across seasons

Abstract

Aflatoxin contamination along the processing points of locally made complementary food composite needs to be ascertained and minimized to reduce exposure to weaning children. The study established the concentrations of total aflatoxin (TAF) and aflatoxin B1 (AFB1) along the processing points of locally made malted millet sesame soybean composite (MMSSC) across season one (wet) and season two (dry) and determined children's exposure to them. A total of 363 samples were collected in 2019. TAF and AFB1 concentrations were determined quantitatively using an enzyme-linked immunosorbent assay (ELISA). Consequently, exposure of individual children was assessed as Estimated Daily Intake (EDI), (ng kg−1 bw day−1). All the samples along the processing points had detectable concentrations of TAF and AFB1 ranging from 0.578 μg kg−1 to 1.187 μg kg−1 and 0.221 μg kg−1 to 0.649 μg kg−1 respectively. Contamination was highest in raw materials; soybean (Glycine max) > sesame (Sesamum indicum), followed by stored composite, freshly prepared composite, and least in millet (Eleusine coracana). Contamination varied significantly across seasons with the wet season having higher contamination than the dry season at P = 0.05. All samples (100%) were within the European Commission (EC) acceptable maximum tolerable level for TAF and AFB1 (4 μg kg−1 and 2 μg kg−1) respectively for processed foods for general consumption. But were below the EU acceptable maximum tolerable level for TAF and AFB1 (0.4 μg kg−1 and 0.1 μg kg−1) respectively for processed baby foods cereals. However, all were within the United States- Food and Drug Authority (US-FDA) and East African Community (EAC) set maximum acceptable limit of 20 μg kg−1 for TAFs, 10 μg kg−1 and 5 μg kg−1 for TAF and AFB1 respectively. Conversely, exposure to these toxins was much higher than the Provisional Maximum Tolerable Dietary Intake (PMTDI) of 0.4 ng kg−1 bw day−1 to 1.0 ng kg−1 bw day−1. A significant difference in exposure to both toxins was observed with the weight. The age of 5 months was the most exposed. A concerted effort is needed to reduce children's exposure to MMSSC to TAF and AFB1, taking sesame and soybean as priority ingredients and proper storage based on season to control contamination.