Mexican solution for aflatoxin contamination in Ghana

October 14, 2019
A translation for this article is available in French

Aflatoxin does not affect the taste, smell, or appearance of the vegetables and grains it contaminates, but its effects can harm animals and the quality of crops, and it can be deadly if consumed in large amounts. Aflatoxin is a substance that is produced by certain types of mould that can grow on crops in the field, in storage, or while being transported to the market.

Farmers in many hot, humid climates are at risk of aflatoxin developing on crops like maize, groundnuts, and grains, but farmers in Mexico have adopted methods for successfully controlling aflatoxin—and they are sharing these methods with Ghanaian farmers.

The Mexican Embassy and Ghana Standards Authority held a meeting in May to discuss the risks of aflatoxin to the health of humans and animals, and to the economy.

For over 3,000 years, Mexicans have used a traditional Mayan method of processing and preparing grains and vegetables at risk of contamination. This method is called nixtamalization. It involves boiling produce in an alkaline solution such as lime water and/or preparing dough using limestone. Audience members at the meeting in May had concerns about the taste of foods made with this method, but other high-alkaline foods could perhaps act as a substitute.

Maria de los Angeles Arriola Aguirre is the Mexican Ambassador to Ghana. She says, “Thanks to this technology, Mexico is a country free of aflatoxin.” She explains that not only does the limestone remove aflatoxin, but it adds calories and calcium to the dough being prepared. She adds, “We can see the change in the future generations by better bones.”

Wet weather, moist storage, and unsealed containers can cause aflatoxin to develop and grow.

Aflatoxin cannot be destroyed through cooking or fermentation, but Aldo Rosales from the International Maize and Wheat Improvement Center (CIMMYT) says nixtamalization provides a natural solution for Ghanaians to test when they prepare maize dishes. Mr. Rosales says the process can remove 97% to 100% of aflatoxins in the crops.

More information about aflatoxin

Grains, tubers, nuts, and oilseeds are key dietary staples in Ghana. These are the crops that are most at risk from aflatoxin. The risks go beyond simply reducing the quality of produce. People who consume contaminated food can develop serious health problems, including cancer, liver damage, stunted growth in children, and even death. People with weaker immune systems are at higher risk, including children, HIV-positive persons, and those infected with hepatitis B. One hundred and twenty-five people died in Kenya in 2004 from exposure to aflatoxin.

Crops are not the only way humans are exposed to aflatoxin. If livestock consume feed contaminated with aflatoxin, it can be transferred to their milk, eggs, and meat. In chickens, the symptoms of infection include weight loss, reduced egg production, and even death.

Aflatoxin also affects economic health, both for individuals and on a national basis. Farmers, transporters, and marketers cannot detect aflatoxin in their products before selling, but their health and those who consume their products are risk. Also, high levels of aflatoxin result in crops being barred from international trade and in some cases destroyed, resulting in economic loss.

Learn more about nixtamalization in this video from CIMMYT: https://www.youtube.com/watch?v=TIs3gjOPevw

For more information on aflatoxin in maize, read our backgrounder on reducing post-harvest loss in maize: http://scripts.farmradio.fm/radio-resource-packs/110-farm-radio-resource-pack/backgrounder-reducing-post-harvest-losses-maize/

This interview script also provides good information from scientists about aflatoxin: http://scripts.farmradio.fm/radio-resource-packs/package-79/aflatoxin-enemy-of-food-and-people/