Blocking growth stunting toxins in food IITA

Healthy vs contaminated maizeHarmless competitors used to block growth-stunting toxins from food may help children in West Africa grow up healthier, and IITA researchers are working toward a way to make it happen.

The maize on the left of the image to the right is contaminated by aflatoxins. Clean, healthy maize is on the right.

They found a less toxic strain of a fungus that grows on grain stored in warm, humid conditions. It can displace harmful strains that produce large amounts of aflatoxins— toxic chemicals known to cause liver cancer and, through IITA research, recently shown to be associated with below-average height and weight among West African children.

This innovative technique is called competitive exclusion. It’s in large-scale testing for cotton in the US, but it has never been used in Africa. In early December, the German development agency BMZ committed 1.2 million Euro to a 3-year project to develop a biological control for aflatoxin in West Africa.

The idea is to keep out the fungal strain that produces aflatoxins by introducing and establishing a strain that doesn’t produce toxins. IITA scientists have started identifying safer strains that can be tested further as a promising means to lessen aflatoxins in maize, which is a staple food for African families.

“This biological control approach offers great promise to produce safer food, and we are working towards making it a reality,” said IITA plant pathologist Dr. Ranajit Bandyopadhyay.

People in the region don’t see the effects of aflatoxins on their crops and health because they aren’t immediate. But that’s changing. In 2001, the EU lowered its limit on aflatoxin levels in crops for import to 4 parts per billion, which is well below the currently-accepted safe limit of 20 parts per billion. The World Bank estimates this policy change will cost African countries about US$670 million in trade per year. This means work by IITA researchers to reduce aflatoxin contamination can make a significant contribution to family incomes and the health of millions of African children.


February 2003