AFLATOXINS are naturally-occurring mycotoxins that are produced by many species of Aspergillus, a fungus.
According to online encyclopaedia Wikipedia, aflatoxins are among the most carcinogenic substances known.
After entering the body, aflatoxins are metabolised by the liver to a reactive intermediate.
Aflatoxin-producing members of Aspergillus are common and widespread in nature. They can colonise and contaminate grain before harvest or during storage. Host crops are particularly susceptible to infection by Aspergillus following prolonged exposure to a high humidity environment or damage from stressful conditions such as drought, a condition which lowers the barrier to entry.
The native habitat of Aspergillus is in soil, decaying vegetation, hay, and grains undergoing microbiological deterioration, and it invades all types of organic substrates whenever conditions are favorable for its growth. These conditions include high moisture content and high temperature.
Crops which are frequently affected include cereals (maize, sorghum, pearl millet, rice, wheat), oilseeds (peanut, soybean, sunflower, cotton), spices (chili peppers, black pepper, coriander, turmeric, ginger), and tree nuts (almond, pistachio, walnut, coconut, brazil nut).
The toxin can also be found in the milk of animals which are fed contaminated feed, as appears to have been the case in Cyprus.
In the US, the acceptable level of total aflatoxins in foods is less than 20 ?g/kg, except for Aflatoxin M1 in milk, which should be less than 0.5 ?g/kg.
If aflatoxin is detected in milk, it is critical that records be maintained of all feeds, feeding practices, milk quantities and contamination levels, plus animal health and performance. If the grain or related feed is fed to other animals, these records should be maintained also.
For most producers, no visual symptoms of aflatoxicosis will be observed in the animals. However, high concentrations of aflatoxins and/or prolonged duration may cause visual symptoms in cattle, especially young calves. Beef and dairy cattle are more susceptible to aflatoxicosis than sheep and horses.
Feed refusal, reduced growth rate and decreased feed efficiency are the predominant signs of chronic aflatoxin poisoning. In addition, listlessness, weight loss, rough hair coat and mild diarrhoea may occur. The disease may also impair reproductive efficiency.
High-level aflatoxin exposure produces an acute necrosis, cirrhosis, and carcinoma of the liver exhibited by hemorrhage, acute liver damage, edema, alteration in digestion, and absorption and/or metabolism of nutrients.
No animal species is immune to the acute toxic effects of aflatoxins including humans; however, humans have an extraordinarily high tolerance for aflatoxin exposure and rarely succumb to acute aflatoxicosis.
Children, however, are particularly affected by aflatoxin exposure, which can lead to stunted growth and delayed development. Chronic exposure also leads to a high risk of developing liver cancer.
Medical research indicates that a regular diet including apiaceous vegetables such as carrots, parsnips, celery and parsley, reduces the carcinogenic effects of aflatoxins.
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