The Aflatoxin Menace

Agriculture is the backbone of Kenya’s economy. It is one of the most crucial components in National development and economic growth. Any form of impediment to Agriculture is a threat to food security in the country. Risk of aflatoxin/mycotoxin contamination of food and feed in Kenya and the African continent as a whole is rampant owing to several environmental, agronomic and socio-economic factors.

 

Case Studies

Alarming rates of aflatoxin contamination were reported in 2004-2005 leading to 406 reported cases and 157 deaths including condemning and seizing of household maize stocks for destruction in order to end further risk to human and animal health. In 2010, after the government boosted maize production in Eastern and coast province, over 2.3 million bags of maize ere seized and lost to aflatoxin contamination.

What is Mycotoxin?

Simply put, mycotoxins are secondary fungal metabolites that contaminate agricultural commodities and can cause sickness or death in humans and animals. They are poisonous compounds produced by certain fungi which often contaminate crops like maize, rice, wheat sorghum, millet, nuts etc.Maize which is a major staple food in Kenya, is particularly affected by a mycotoxin produced by Aspergillus flavus and Aspergillus.

Controlling or reducing infection and regulating the factors that increase the risk of contamination in the field for maize will go a long way in controlling aflatoxins.

Management practices that reduce the incidence of mycotoxin contamination in the field include; timely planting, optimal plant densities, proper plant nutrition, avoiding drought stress, controlling other plant pathogens, weeds and insect pests and proper harvesting.

A paper done on this subject recently acknowledged that several technologies have been tested in Africa to reduce mycotoxin risk. Field management practices that increase yields may also prevent aflatoxin. They include; use of resistant varieties, timely planting, fertilizer application, weed control, insect control and avoiding drought and nutritional stress.

Other options to control the toxin causing fungi A.flavus contamination in the field are use of atoxigenic fungi to competitively displace toxigenic fungi, and timely harvest.

Post –harvest interventions that reduce mycotoxins are; rapid and proper drying, sorting, cleaning, smoking, drying, post-harvest insect control, and the use of botanicals or synthetic pesticides as storage protectant.

Another approach is to reduce the frequent consumption of’ high risk’ foods(especially maize and groundnuts) by consuming a more varied diet and diversifying in to less risky staples like sorghum and millet.

Factors of stress in crop production and handling during and after harvest are associated with mycotoxin production. Emphasis on end product monitoring alone has proved ineffective and costly. Mitigation of aflatoxin contamination lies in implementing control measures at each stage of the value chain i.e. land preparation, planting, harvest, drying, storage, transportation and processing.