A survey on the occurrence of aflatoxin M1 in milk samples in Ardabil, Iran

Mycotoxins are natural food and feed toxic contaminants produced as a result of fungal growth on agricultural materials during storage and/or transportation. The purpose of this study was survey on the occurrence of aflatoxin M1 (AFM1) in milk samples from Ardabil, Iran. Ninety samples were collected from local shops of the Ardabil city during different seasons in order to address representative data on AFM1 in milk consumed by people in this city. AFM1 was analyzed by Enzyme Linked Immuno Sorbent Assay (ELISA). All of the samples (100%) were contaminated with AFM1 in concentration levels ranged from 2.9 to 85 ng/kg. In 30 samples (33% of total samples) the AFM1 level was higher than 50 ng/kg, the maximum residue limit (MRL) accepted by European Union for AFM1 in milk. The difference of AFM1 level between seasons was statistically significant (P < 0.05). The highest and lowest levels of contamination were detected in winter and summer seasons which were 17.4 and 56.3 ng/kg, respectively. This is the first report on the occurrence of AFM1 in milk samples of Ardabil, one of the main milk-production regions in Iran. The contamination with AFM1, in this area is most probable because of contaminated feed consumed by cattle, which needs prompt effort to reduce the risk of contamination.