Aflatoxin M1 in bulk-tank raw milk produced in a low risk area

The present study was designed to determine the levels of aflatoxin M1 (AFM1) and its seasonal variation in bulk tank cow milk collected from dairy farms located on the Italian island of Sardinia. Cow bulk tank milk samples (No 356) were collected from 178 farms twice a year, during the winter and summer seasons. All samples were analysed for AFM1 with a commercial ELISA kit. Confirmation of AFM1 positive samples (>10 ng L-1) was accomplished by using high-performance liquid chromatography (HPLC) with a prior clean-up step using immunoaffinity columns. AFM1 was found at levels ≥5 ng L-1 in 112 samples (31.5%) but only one exceeded the maximum EC level (50 ng L-1). There was no seasonal influence on the aflatoxin content of the milk samples analysed.