Aflatoxin exposure and risk assessment among peri-urban low income population in Kampala Capital City, Uganda

Abstract

Kampala Capital City (KCC) is home to over 3.7 million residents majority of whom are low -income earners who depend on low-cost cereals and legumes for food. These foods are mainly purchased from retail shops and open markets that expose them to mould and aflatoxin contamination. This study assessed total aflatoxin exposure arising from consumption of maize and groundnuts based products by KCC dwellers, and the associated cancer risk. The study was conducted in two divisions of KCC targeting mothers (15–49 years) and children (6–59 months). Results indicate that the majority of the household heads were engaged in low-income occupations with 35 % earning less than US $ 1 a day. Over half of the households purchased cereals and legumes once to twice a week and stored the food in polypropylene or polythene bags. The mean maize consumption rate was 128.7 and 189.9 g/person/day for children and mothers, respectively, while that for groundnuts was 71.6 (children) and 110 (women) g/person/day. Groundnut flour samples recorded the highest proportion (76 %) of samples that tested positive for aflatoxins with a mean total of 37.94 µg/kg (0.04 - 296.4 µg/kg). Only 28 % of the maize flour samples tested positive with a mean total of 27.9 µg/kg (0.04 - 345.8). The mean total aflatoxin levels in both maize (27.9 µg/kg) and groundnuts (37.94 µg/kg) were above the minimum regulatory limit of 10 µg/kg set by the Uganda National Bureau of Standards. The estimated total aflatoxin intake ranged between 0.01 and 0.91 µg/kg/BW/day in both women and children while the estimated total aflatoxin exposure was above the daily intake limit of 0.017 µg/kg BW/day recommended by the European Food Safety Agency. The derived risk of developing primary liver cancer was 5.4 and 7.6 cancer cases per 100,000 individuals per year for children 6–59 months and mothers 15–49 years respectively. The study findings suggest that consumption of maize and groundnuts based foods by low income dwellers in KCC is associated with health risks as it could lead to development of primary liver cancer. Interventions such as; sensitization of all value chain actors, enforcement of existing aflatoxin standards, and boosting household income to enhance household dietary diversity need to be put in place to reduce aflatoxin exposure and its related health risks.