A High Sensitivity LC/MS/MS Method with QuEChERS Sample Pre-treatment for Analysis of Aflatoxins in Milk Powder Samples

Aflatoxins (B1, B2, G1 and G2) are metabolites produced by fungi (Aspergillus favus and Aspergillus parasiticus) in crops, animal feed and dairy products. Aflatoxins are highly toxic contaminants in food and feed and their amounts increase under bad storage conditions favourite for fungal growth. Aflatoxin M1 is a hydroxylated metabolite of aflatoxin B1 found in milk of cow fed with a diet contaminated with aflatoxin B1. Aflatoxin B1 is known the most carcinogenic among all the aflatoxins, and hence its metabolite aflatoxin M1 is given critical attention. Strict regulations for aflatoxin M1 in milk and dairy products have been set. For example, European Union (EU) limits the level of aflatoxin M1 to no more than 0.05 μg/kg in milk and dairy products and 0.025 μg/kg in infant food. We present a high sensitivity LC/MS/MS method for quantitative analysis of the five aflatoxins (B1, B2, G2, G2 and M1) in milk powder incorporating QuEChERS sample pre-treatment procedure, which is more cost effective as compared to the traditional procedure using immunoafflnity column (IAC). High sensitivity and good recoveries were achieved using this LC/MS/MS method.