Mycotoxin problem in Africa: Current status, implications to food safety and health and possible management strategies

ArticleinInternational Journal of Food Microbiology 124(1):1-12 · June 2008with123 Reads
DOI: 10.1016/j.ijfoodmicro.2008.01.008 · Source: PubMed
Abstract
Mycotoxins are toxic secondary metabolites of fungal origin and contaminate agricultural commodities before or under post-harvest conditions. They are mainly produced by fungi in the Aspergillus, Penicillium and Fusarium genera. When ingested, inhaled or absorbed through the skin, mycotoxins will cause lowered performance, sickness or death on humans and animals. Factors that contribute to mycotoxin contamination of food and feed in Africa include environmental, socio-economic and food production. Environmental conditions especially high humidity and temperatures favour fungal proliferation resulting in contamination of food and feed. The socio-economic status of majority of inhabitants of sub-Saharan Africa predisposes them to consumption of mycotoxin contaminated products either directly or at various points in the food chain. The resulting implications include immuno-suppression, impaired growth, various cancers and death depending on the type, period and amount of exposure. A synergistic effect between mycotoxin exposure and some important diseases in the continent such as malaria, kwashiorkor and HIV/AIDS have been suggested. Mycotoxin concerns have grown during the last few decades because of their implications to human and animal health, productivity, economics of their management and trade. This has led to development of maximum tolerated limits for mycotoxins in various countries. Even with the standards in place, the greatest recorded fatal mycotoxin-poisoning outbreak caused by contamination of maize with aflatoxins occurred in Africa in 2004. Pre-harvest practices; time of harvesting; handling of produce during harvesting; moisture levels at harvesting, transportation, marketing and processing; insect damage all contribute to mycotoxin contamination. Possible intervention strategies include good agricultural practices such as early harvesting, proper drying, sanitation, proper storage and insect management among others. Other possible interventions include biological control, chemical control, decontamination, breeding for resistance as well as surveillance and awareness creation. There is need for efficient, cost-effective sampling and analytical methods that can be used for detection analysis of mycotoxins in developing countries.
    • "Aflatoxin M1 is a class 2B (possible) human carcinogen. Maize, the staple food in Kenya, is often contaminated with high concentrations of aflatoxins and this has caused acute fatal aflatoxicosis in humans [11][12][13][14][15][16][17]. High concentrations of aflatoxins and trichothecenes in feed can also cause high mortality in cattle [18], while chronic aflatoxin poisoning in dairy cattle leads to a decrease in feed conversion efficiency, milk production and reproductive efficiency [19, 20]. "
    Article · Aug 2016
    • "Mycotoxins are harmful to both human and animal health, and exposure is mainly through consumption of contaminated food and feeds, respectively. Mycotoxin contamination in Africa is currently inevitable in the food production cycle and efforts are mainly geared towards removing contaminated foods and feeds from consumption or minimizing levels present to meet permitted legal limits [3, 4]. In developed countries, stringent regulatory policies control the levels of mycotoxins in food; this is in contrast to the situation in developing countries, where enforcement of existing regulations is virtually non-existent [5]. "
    Article · Aug 2016
    • "Thus, heavy A. flavus innoculums may have been introduced to the crop during growth and maturation or during pre-storage handling. Drought stress and delayed harvesting also increase the risk of field contamination with aflatoxins (Wagacha and Muthomi, 2008). However, our findings demonstrate that PICS bags can prevent further aflatoxin accumulation in maize during postharvest storage provided the maize is dried to below 14% m.c. "
    [Show abstract] [Hide abstract] ABSTRACT: Field trials were conducted in small-scale farmers' grain stores in an aflatoxin endemic region to assess the effect of storing maize in triple layer hermetic (PICS™) bags on aflatoxin contamination. Shelled maize grain was purchased from farmers, and filled into PICS bags, woven polypropylene (PP) and jute bags and kept in the farmers' own stores for 35 weeks. Grain moisture content, total mould count and mould incidence levels were examined at onset and after every 7 weeks during the 35 weeks of storage. Aflatoxin contamination was examined at onset, and after 14, 28 and 35 weeks. Ambient temperature and r.h. in the trial site and in all the bags, as well as oxygen and carbon dioxide levels in the PICS bags were also monitored. Initial moisture content (m.c.) of maize varied from farmer to farmer and ranged between 12.4 and 15.0%. The m.c. of maize stored in PICS bags remained significantly higher (P < 0.05) than in PP and jute bags in the last 14 weeks of storage. Total mould count and aflatoxin contamination of maize stored at an initial m.c. < 13% and 13% ≤ m.c. ≤ 14% increased significantly in PP and jute bags but not in PICS bags. After 35 weeks, total aflatoxin of maize stored in the PICS bags at an initial m.c. < 13% and 13% ≤ m.c. ≤ 14% did not change where as it increased 5e8 folds in the PP and jute bags. Total mould count and aflatoxin contamination of maize stored at an initial m.c. > 14% increased profusely in the three types of bags. Our findings demonstrate that storing maize in PICS bags can prevent accumulation of aflatoxin in rural farmers' stores if grain moisture is <14%.
    Full-text · Article · Jul 2016
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