Food handling practices, the prevalence of aflatoxin dietary exposure and its associated factors among children aged 6–23 months in Bukombe District, Tanzania

Background

Complementary foods are provided to newborns and early children to replace breast milk, which, after six months of exclusive breastfeeding, is no longer adequate to meet the child's nutritional needs. However, foods like dairy, grains like maize, sorghum, and millet, as well as nuts like groundnuts, which are frequently suggested as supplemental foods have all been linked to aflatoxin contamination. Understanding how caregiver preparation and storage practices of complementary flour affect children's aflatoxin exposure is crucial.

Objective

To determine the prevalence of dietary exposure to aflatoxin and its associated factors in children aged 6–23 months complemented with cereal-based foods in the Bukombe District of Geita Region in Tanzania.

Methodology

An analytical cross-sectional study was used to survey 342 households of children aged 6–23 months. Fifty complementary flour samples from 50 of the total households were chosen at random and tested for aflatoxin using the HPLC technique and standard methods. A semi-structured questionnaire was used to assess parents'/caregivers' food handling and preparation practices and the amount of food consumed. The obtained results were used to estimate aflatoxin dietary exposure of children in the study.

Results

Most of the children (86%) were exposed to aflatoxin through diet with a median value of 0.3 μg/kg-bw/day mainly linked to age and breastfeeding status. The majority of the exposed (86%) were above the reference limit of 0.04 μg/kg-bw/day. Most parents (98.5%) chose maize as the main component of complementary flour, either on its own or mixed with other cereals and winnowing and dehulling as the most and least common practices with the proportion of 78.9% and 9.4% respectively. Furthermore, a majority (88%) of flour samples were contaminated with aflatoxin B1 and total aflatoxin with log mean values of 1.2 ± 0.81 and 1.5 ± 0.68 μg/kg respectively which were above the Tanzania reference limit of 5 μg/kg and 10 μg/kg respectively. Contamination was significantly (p < 0.05) associated with location (Fisher's exact value = 6.68, p = 0.036), source of cereals (Fisher's exact value = 56.4 p = 0.025), and storage time (Fisher exact value = 23.8, p < 0.001).

Conclusion

In view of the findings, aflatoxin contamination in flours used for complementary feeding was beyond tolerable limits, hence increasing the risk of children's dietary exposure. This suggests that strengthening strategies to control aflatoxin contamination of maize throughout the food chain and teaching parents about preparation and storage methods that reduce aflatoxin in cereals/flour are important.