Maize pre-storage practices and their influence on Aflatoxin contamination of maize in Makueni county, Kenya

Background: Aflatoxicosis resulting from consumption of maize contaminated with aflatoxins mainly due to poor harvesting and storage of grains, poses a significant public health problem in many countries. Furthermore Aflatoxins related disease outbreaks, associated with a degree of mortality at times have been reported in Makueni County in Kenya. Objective: To determine maize pre-storage conditions and practices that influence development of aflatoxin in Makueni County, Kenya. Study design: A comparative descriptive study conducted in Kibwezi and Kilome sub-counties of Makueni County, Kenya. Methods: Four hundred and fifty households (225 from each study site) which had maize in household were randomly sampled and household heads or their representatives interviewed using interview schedules. Are presentative sub-sample of households had their maize samples taken for moisture content and aflatoxin determination. Results: The results showed that households allowed their maize to stay for a mean period of 25 days in low altitude and 45 days in high altitude after attaining maturity, and overwhelming majority (over 90%) of households removed outer covering (husks) of maize cobs during harvesting. Majority (96.3%) of households in both study sites dried their maize in open sunshine (sun drying) after harvest with majority of them (over 75%) placing maize on top of plastic sheeting material to avoid contamination, and to make their maize dry properly and faster. The drying time for maize was shorter in low altitude (mean14 days) than in high altitude (mean17 days). The study findings further showed that duration of maize in the field before harvest was significantly positively correlated with insect pests’ infestation in maize while in storage (P<0.05). Results further revealed significant negative correlation between duration of maize in field prior to harvest and moisture content in maize (P<0.05). The placing of maize on top of impervious sheeting material/layer during drying was associated with proper maize storage (P<0.05). Duration of drying of maize after harvest especially in higher altitude area had significant negative correlation with aflatoxin content in maize as well as in moisture content (P<0.05). Conclusion: Some maize harvesting and drying practices are associated with insect pests’ infestation as well as certain aspects of aflatoxin contamination in maize. Thus adoption and improvement of these practices will more likely contribute to proper maize handling and storage with subsequent reduction of aflatoxin contamination of maize.