Aflatoxin levels in maize and maize products during the 2004 food poisoning outbreak in eastern province of Kenya
AbstractBackground: On 10th May, 2004 food samples suspected to have caused acute poisoning in Makueni district were received at the National Public Health Laboratory Services (NPHLS). On analysis, they were found to be highly contaminated with aflatoxin B1. More cases of poisoning were reported in the district and in neighbouring districts of Kitui, Machakos and Thika. As at 20th July, 2004 the Ministry of Health was aware of 317 cases of which 125 resulted in deaths.
Objective: To assess the magnitude of aflatoxin contamination of maize and maize products in the affected areas.
Design: Random environmental sampling of maize and maize products and case/control samples of the same in the affected regions and subsequent determination of aflatoxin levels using immunoaffinity coupled with solution fluorometry.
Setting: National Public Health Laboratory Services, Ministry of Health, Kenya, from May to August, 2004.
Subjects: A total of 480 samples comprising 362 random environmental samples, 26 cases and 92 controls were collected and analysed. The foods analysed included maize grains, maize flour and dehulled dry maize, traditionally known as muthokoi.
Results: Forty six point four per cent of the environmental samples, 15% of cases and 29.3% of controls were within the maximum permissible limit of 20µg implying that over 50% (54.4) of the total did not comply and would be regarded as unfit for human consumption. 6.9% of the environmental samples, 57.7% of cases and 21.7 of controls had levels beyond 1000µg/Kg. The amount of aflatoxin observed in the food samples had a range of 0-58,000 µg/Kg.
Conclusion: The population in the affected region was exposed to high levels of aflatoxin. There is need to address the issue of pre and post harvest handling of grain and establishing monitoring and surveillance for early detection and intervention.
East African Medical Journal Vol.82(6) 2005:275-279