Aflatoxin - Global Health and Economic Risks
Aflatoxin is a known carcinogen that affects 25% of global food crops, including corn, the most widely produced grain in the wrold. Over 5 billion people in developing countries around the world (~ 70% the global population) are at risk of chronic exposure to aflatoxin.
Aflatoxins are toxic at very low levels. They are produced by the fungi Aspergillus flavus and Aspergillus parasiticus, usually during conditions of drought, high heat and humidity.
Aflatoxin threatens the health of people and livestock, and the economic prosperity of farmers and grain handlers in the U.S. and around the world.
Aflatoxin contamination in corn has been linked to:
- Up to 28% of global liver cancer cases
- High prevalence rates of childhood stunting in Africa
- Pet food recalls
- Economic loss (U.S.): $200 - 300 M in loss to corn during normal years; $1 B or more in drought years (like 2012)
- Economic loss (Sub Saharan Africa): In 2010, 10% of Kenyan maize was aflatoxin contaminated, a $100 M economic loss. (The estimated annual loss to African food exporters of cereals, dried fruit and nuts from attempting to meet EU aflatoxin standards is roughly $750 M).
Current Testing Not Helping Farmers or Grain Handlers
In U.S. grain handling operations, chemical tests are used to detect aflatoxin in corn. These tests are too slow, taking > 10 minutes to run, while grain elevators need to unload a truck every 2 minutes.
Additionally, testing suffers a 25 - 40% error rate, due largely to a sampling process dependent on the representative validity of a 5 pound composite sample taken from a 50,000 pound truckload. The result is greater risk of contaminated corn entering the food supply at the grain elevator, as well as downstream at feed mills and food processors that are receiving truckloads of corn.
While increased sampling per truck would reduce the high sampling error, it’s too difficult to pull more corn or run more tests without causing further delay to operations.
The other big problem is that a farmer's truck will get docked in value or rejected if the sample registers contamination levels > 20 parts per billion, even though contamination is likely in just a small "hot spot" in the truck. There’s currently no way to remove the bad corn and protect the value of the good corn.
In developing countries chemical test kits are not widely used due to cost and logistics, resulting in greater exposure and health risk (the fluorometers used to read the chemical tests cost thousands of dollars).
Aflatoxin contaminated corn. Often the contaminant is within the kernel and not visible to the naked eye.
In many developing countries farmers dry their corn in the open air, or on tarps, further enhancing aflatoxin fungal conditions.