Assessment of aflatoxin exposure among mothers (15-49 years) and children (6-59 months) in Rubaga and Nakawa Divisions of Kampala Capital City

Abstract

Aflatoxins are food contaminants that affect mostly cereals and legumes that are poorly handled and stored at high temperature and humidity. Aflatoxins are highly potent group 1 hepatocarcinogenic, teratogenic, mutagenic, immuno-toxic and neurological agents. Out of an estimated global population of 7.5 billion people, over 4.5 billion rely on diets that are contaminated with aflatoxins. Kampala Capital City (KCC) is among the fastest growing cities in Africa with an annual growth rate of 5.6% and is home to over 1.65 million residents many of whom are low income earners and depend on low cost cereals and legumes. The major foods consumed by peri-urban dwellers in KCC are purchased from retail shops and poorly structured open markets making them prone to aflatoxin contamination. Due to limited incomes, a preference for low cost cereals and legumes with little thought of food safety is inevitable among the population living in peri-urban areas of KCC. It was therefore hypothesized that a large proportion of the peri urban dwellers in KCC was exposed to high dietary aflatoxins. The study was conducted in two divisions of Kampala Capital City Authority (KCCA) from which 372 households were randomly selected to assess the aflatoxins food contamination, aflatoxin exposure and aflatoxin risk characterization among mothers (15-49years) and children (6-59 months). Total aflatoxins were quantified in foods using ELISA Ridascreen® (R-Biopharm, Darmstadt, Germany). Total aflatoxin exposure was estimated probabilistically based on a triangular distribution and 10,000 simulations using @Risk Software (Palisade, Ithaca, USA) while risk characterization was done using the JEFCA Margin of Exposure and Population Cancer risk models. The results show presence of total aflatoxins, that included AFB1, AFB2, AFG1, and AFG2 in 100, 39, 37 and 7 samples respectively and the levels varied from 0.04 to 452.05 μg/kg. The highest mean of total aflatoxins at 219.91 μg/kg was detected in porridge mix, followed by the average of 197.43 μg/kg of total aflatoxins in cassava flour. The results indicate high total aflatoxin exposure levels for both mothers (15-49 years) and children (6-59 months) with a range of 0.1-1.1(μg/kgBW/day). The estimated margin of exposure from consumption of aflatoxin contaminated foods was 73.69 and 63.14 for children (6-59 months) and mothers (15-49 years) respectively. The risk of primary liver cancer for children and mothers was 5.4 and 7.59 per 100,000 persons per year respectively. The results indicated that there is a high risk of developing primary liver cancer among the people of KCC resulting from consumption of aflatoxin contaminated cereals and legumes. There is a need to put in place measures to reduce community exposure to aflatoxins. Such measures may include; sensitization of all value chain actors on the health risks associated with consumption aflatoxin contaminated staples and management strategies, enhancing the enforcement of existing aflatoxin standards and dietary diversification.