Last season, Mollene Kachambwa lost one tonne of maize. Weevils and fungi destroyed one-fifth of the grain her family harvested. This season, however, the weevils and fungi might have to find a new home.
To protect this year’s harvest from pests, Mrs. Kachambwa stored her maize in an airtight, galvanized metal bin. Otherwise known as a “silo,” the shiny container takes pride of place on her farm in the village of Kachambwa, in Mashonaland Central Province, 75 kilometres northeast of Zimbabwe’s capital, Harare.
Farmers like Mrs. Kachambwa often spend more than US$50 every season on pesticides to protect their stored grain from weevils. But they have little protection against the fungi which produce a poisonous chemical known as aflatoxin. Exposure to aflatoxin has been linked to weakened immunity and a higher risk of cancer.
According to the United Nations’ Food and Agriculture Organization, 25 per cent of world food crops are affected by aflatoxin contamination. Research by the International Food Policy Research Institute suggests that an estimated 26,000 people in sub-Saharan Africa die every year of liver cancer associated with chronic exposure to aflatoxin.
But a new project is investigating the effectiveness of airtight metal silos and thick plastic “super bags” in reducing aflatoxin contamination in stored maize.
Charlene Ambali is the principal investigator and project coordinator at Action Contre la Faim, one of the project partners. She says: “If aflatoxin levels are high in maize produced by farmers in Zimbabwe, this could pose a risk to human health and also … the trading of maize, a staple crop in the country.”
Ozwell Chitono is an agriculture extension worker in the Shamva District of Mashonaland Central. He says that poor drying and storage methods contribute to aflatoxin growth.
Dr. Loveness Nyanga is a researcher and senior lecturer with the University of Zimbabwe. Dr. Nyanga says: “Communities [are also] concerned about their continuous use of pesticides and fertilizers … [and] worried that this was a health hazard. They welcomed the airtight technology, as there was no need to use pesticides on their harvested grain.”
Alice Mhonda farms in Mushowani village. Last season, she harvested two tonnes of maize and stored it in airtight bags. She stacked the bags neatly on log frames in a room outside her kitchen.
Mrs. Mhonda says: “I will open the bags in February to see if this method has worked. I am happy I have not had to buy any pesticides. Last season, I used seven tins of pesticide but still lost five bags of maize to weevils, and some of it went mouldy.”
The metal storage bins are a welcome novelty in Kachambwa village. They have boosted business for tinsmith Francis Pokoti, who has built more than 100 metal bins of various sizes for the project, and for other private customers who are keen to try out the new technique for themselves.
Mrs. Kachambwa says: “I am confident my maize is safe in the metal bin. I have been taught to dry the maize properly before storing it. I put a burning candle to … [remove the oxygen from] the bin before I seal it. I have also learnt how to test for moisture content in my grain before I store it in the bin.”
To read the full article on which this story was based, Zimbabwe’s Smallholder Farmers Seek Address Food Security and Health Risks with Air Tight Storage Technology, go to: http://www.ipsnews.net/2015/10/zimbabwes-smallholder-farmers-seek-address-food-security-and-health-risks-with-air-tight-storage-technology/ 
Photo: Farmers Enock Gwangwawa and Alice Mhonda from Shamva District in Zimbabwe, have switched to storing their maize grain in airtight hermetic bags to prevent weevil and fungus damage. Credit: Busani Bafana/IPS