Natural occurrence of aflatoxin residues in fresh and sun-dried meat in Nigeria

INTRODUCTION: In recent times, food safety and security have generally remained basic human needs, therefore because of the largely unregulated nature of the Nigerian markets, coupled with the poor housing and feeding conditions to which animals are subjected in the abattoirs, a survey for assessing potential mycotoxin exposure through meat consumption was undertaken. METHODS: Eighty Samples of meat bought randomly from 5 major markets distributed in 5 local government areas of Oyo state , Nigeria were analysed for contaminating mycoflora using the plate count and micromorphological methods, while aflatoxin detection and quantification was by Thin Layer Chromatography (TLC). RESULTS: Mycological analysis of samples revealed a higher contamination level in the sun-dried samples. Eighteen fungi species belonging to 8 genera, namely, Aspergillus, Penicilliu, Alternaria, Cladosporium, Fusarium, Neurospora, Rhizopus and yeast were identified. The predominant genus Aspergillus yielded 7 species while the potential toxicogenic fungi represented 38% of the isolated mycoflora. The genera requiring higher water activity for growth ( Alternaria, Fusarium and yeast) were not obtained from the dried meat. Aflatoxins B1, B2, G1 and G2 were detected in all the samples analysed. The fresh samples with the exception of the total aflatoxin G (AFG) in kidney gave the highest mean concentrations for all aflatoxins, also an exceptionally high aflatoxin content was found in all the kidney samples. CONCLUSION: Aflatoxin detection in meat should be addressed urgently to avert the possible adverse health effects like aflatoxicosis, exacerbated malnutrition, suppression of growth and immune functions on consumers. Also the animal health inspectors should pay more attention to the feeding conditions of the animals on farm and the abattoirs.