By John Oywa
Aflatoxin is a natural fungi produced by two types of mould, namely aspergillus flavus and aspergillus parasiticus.
The flavus mould is widespread and often found when certain grains are grown and harvested under stressful conditions. The mould occurs in soil, decaying vegetation, hay, and grains undergoing microbiological deterioration, invading all types of organic substrates whenever and wherever the conditions are favorable for its growth.
Favorable conditions include high moisture content and high temperature. The current contamination is caused by high moisture content during harvesting. The recommended content is 13 per cent but most of the harvest in Coast and Eastern Provinces had high moisture content of up to 16 per cent.
NCPB’S Julius Mutua takes maize samples for tests from their silos in Naivasha [PHOTO: ANTONY GITONGA/STANDARD] |
At least 13 different types of aflatoxin are produced, with aflatoxin B1 considered to be the most toxic. While the presence of aspergillus flavus does not always indicate harmful levels of aflatoxin, it does not reduce its harmful potential.
Early Diagnosis
Symptoms of aflatoxin in humans include fever and vomiting. Only cases diagnosed early enough can be treated.
Aflatoxins can also affect animals with devastating results. This means the condemned maize should not be converted into animal feed.
Higher exposure to aflatoxin leads to liver hemorrhage and liver cancer.
The ingestion of high levels of aflatoxins can be fatal, while chronic exposure may result in serious health conditions such as cancer and liver cirrhosis, weakened immune systems, and stunted growth.
In livestock, some mycotoxins are acutely toxic and can cause vomiting and feed refusal, according to the International Food Policy Research Institute.
More than 4.5 billion people in developing countries may be chronically exposed to aflatoxins in their diets.
