Seasonal study of aflatoxin M1 contamination in milk of four dairy species in Yazd, Iran

This survey was conducted to determine the occurrence of aflatoxin M-1 (AFM(1)) in samples of raw milk obtained from cow, sheep, goat, and camel herds in Yazd province during different seasons. Aflatoxin M-1 was analyzed using the competitive enzyme-linked immunosorbent assay technique for screening and high-performance liquid chromatography with fluorescence detection for confirmatory purposes. The detection rates of AFM(1) in cow, sheep, goat, and camel milk samples were 46.5%, 21.6%, 20.1%, and 4.03%, respectively. Levels of the toxin in 15.4% of cow milk, 11.5% of sheep milk, and 9.15% of goat milk samples exceeded the legal limit (0.050 mu g/kg) recommended by the Institute of Standards and Industrial Research of Iran; while none of the camel milk samples exceeded the legal limit. The occurrence and levels of AFM(1) in cow milk samples from industrial dairy farms was significantly lower (P <= 0.05) than those from traditional ones. Seasonal variations influenced the occurrence and levels of AFM(1) in cow, sheep, and goat milk; however, no statistically significant seasonal effect was found for camel milk. This study indicates a high occurrence of AFM(1) in cow milk especially those obtained from traditional dairy farms. Therefore, more supervision is required on these farms; and traditional dairy farms should be gradually replaced by industrial ones. (c) 2016 Elsevier Ltd. All rights reserved.