Maize Handling and Contamination by Mycotoxins for Imports and Local Markets in Eswatini

Abstract

Due to local production issues stemming from poor practices and climate, and imported maize facing contamination risks from long-distance transport, Eswatini's overall maize supply presents a high risk of mycotoxin contamination for consumers. This study assessed the prevalence and diversity of mycotoxins in imported and local market maize within Eswatini's six agro-climatic regions. Samples were collected from formal markets, informal markets, and National Maize Cooperation (NMC) delivery trucks supplying imported maize. A total of 100 samples were analyzed out of 195 collected. The results demonstrated a significant difference in mycotoxin contamination based on the source and handling practices. Maize from imported sources was the safest, with 95% of samples showing no presence of the targeted mycotoxins (Aflatoxins B1, B2, G1, G2, and Zearalenone). Formal markets, which source all their stock from NMC, had 91.7% of samples testing negative. In stark contrast, informal markets, which source most of their maize directly from local farmers, had only 46.7% of samples testing negative, making them significantly riskier for consumption. The Lubombo plateau was identified as the region most affected, exhibiting the highest diversity of mycotoxins in informal market samples. These findings highlight the urgent need for proper maize regulation guidelines and intensive monitoring to manage the risk posed by mycotoxin-contaminated maize, particularly in the informal sector.