Objectives:

Aflatoxins are toxic mold metabolites produced by toxigenic strains of Aspergillus species. They have an important role in the occurrence of a number of human diseases such as liver cancer, chronic hepatitis and cirrhosis. When animals eat food stuffs containing aflatoxin B1, these toxins are metabolites and excreted as aflatoxin M1 in milk. These aflatoxins are resistant to thermal inactivation and are not destroyed completely by pasteurisation, autoclaving or a variety of food processing procedures. The aim of this study was to determine the quantity of aflatoxin M1 in pasteurised milk samples in Shiraz.

Methods:

A total of 624 pasteurised milk samples from different supermarkets in Shiraz were collected during 6 months (April–September 2003). After centrifugation of milk samples upper cream layers were completely removed and the lower phases were analysed by enzyme immunoassay for the quantitative analysis of aflatoxin M1.

Results:

Aflatoxin M1 was found in 100% of the milk samples examined. 17.8% of the samples were higher than the maximum tolerance limit (0.05 ppb) accepted by European Union. As compared with other studies, Turkish milk had higher contamination (P < 0.00006), Brazil was the same as our findings and Albania's contamination was less than our results (P < 0.0004).

Conclusion:

Consequently this subject is a serious problem for the public health, especially in infants and children consuming these products. Therefore milk and dairy products have to be inspected routinely for aflatoxin M1 contamination. To achieve a low level of aflatoxin M1 in milk, the dairy cows’ feeds should be kept away from fungal contamination as much as possible.