Aflatoxin is a silent killer that causes liver cancer and suppresses the immune system. It also retards growth and development in children. People exposed to very high aflatoxin concentrations experience liver failure and rapid death. From 2004 to 2006, nearly 200 unsuspecting people in Kenya died in this manner after eating highly contaminated maize. Aflatoxin is a colorless toxin which is invisible and only laboratory tests can confirm its presence.
In Kenya this year, the contamination of the country's main crop - maize- with aflatoxin, a highly poisonous cancer-causing chemical produced by a fungus scientifically known as Aspergillus flavus, was the result of poor drying and storage of the grain following heavy rainfall near harvest time.
A particular toxigenic strain of Aspergillus flavus is largely responsible for the aflatoxin contamination of the crops. But there is a novel way to control contamination using a biological control approach. Experts have identified a locally occurring non-toxic strain of the fungus. This strain can be introduced to the crops prior to harvesting and will safely outcompete and virtually eliminate the toxic aflatoxin producing strain, effectively reducing contamination of the maize grains in fields.
A single application of this "biopesticide" AflasafeTM 2-3 weeks before maize flowering is sufficient to prevent aflatoxin contamination throughout the season and even during grain storage. Note this is not a chemically derived pesticide - but the use of naturally occurring strains of A.flavus to swamp the toxic strains.
Trials in the US have shown that biocontrol in this way has successfuly reduced contamination and in Nigeria provisional registration and use of Aflasafe™ in 2009 allowed farmers to reduce aflatoxin contamination of their crops by 80%.
Research has shown that Aflasafe™ treatments provide long-term benefits and that Aflasafe™ may not need to be applied every year.
Africa-based International Institute of Tropical Agriculture, in partnership with the Nigerian government and the United Nations Industrial Development Organization (UNIDO), is working on obtaining full registration and identifying an entity that would mass manufacture, market, and distribute Aflasafe™ in Nigeria to save the health and income of millions of families.
The researchers are now calling upon the government and the private sector in Kenya to partner with them and make this biocontrol option available to the farmers to save their essential harvests from future aflatoxin contamination.
Source Science Letter July 1st, (2010)