Improved Drying and Storage Practices that Reduce Aflatoxins in Stored Maize: Experimental Evidence from Smallholders in Senegal

Abstract

Proper post-harvest treatment of crops is key to limiting contamination by aflatoxins, potent carcinogens, but little is known about constraints to adoption of best post-harvest practices among smallholder farmers in developing countries. We use a randomized controlled trial with 2,000 maize producers in Senegal to test whether low awareness and/or lack of drying and storage technologies are barriers to storing safe maize. A novel feature of our intervention is that we offered both drying and storage technologies to farmers and evaluated their combined impact. We found that only hermetic (airtight) storage bags caused a statistically significant reduction in total aflatoxin levels after 3–4 months of storage, reducing the likelihood that maize had total aflatoxin levels above safe-to-eat thresholds by 30%. Our results provide practical guidance to lower aflatoxins in staple crops and suggest that strategies to reduce aflatoxins should address issues from harvest to storage in a comprehensive manner.