Occurrence of aflatoxin M1 in cheese processed and marketed in Lebanon

Aflatoxin M1 (AFM1) is the principal hydroxylated metabolite of aflatoxin B1 excreted in milk, and subsequently it can be found in a large variety of dairy products thus posing a potential risk to human health when consuming these products. Considering its significant impact on human health, determination of AFM1 levels in dairy products becomes imperative. The present study was undertaken to investigate, for the first time, the levels of AFM1 in various locally processed (halloumi, baladi, shelal, naboulsi, double cream, feta and akkawi) or imported (white and yellow) cheese types available in Lebanese markets. For this purpose a total of 111 cheese samples were randomly collected from local small dairy farms (53 samples), Lebanese leading dairy industries (38 samples) and imported cheeses (20 samples). Aflatoxin M1 was detected in 67.56% out of the 111 samples analyzed in which the levels of AFM1 in 17.33% of the samples were found to exceed the limits (250 ng/kg) allowed by European Commission (EC). Of the analyzed cheese samples, AFM1 levels in 13 cheeses from small local dairy farms were above the limits set by the EC ranging between 255 and 315 ng/kg. None of the cheese samples collected from the Lebanese leading dairy industries or from the imported types exceeded the permissible limit where the highest recorded levels were 77.2 and 3.95 ng/kg, respectively. The results of this study indicate that continuous monitoring of AFM1 levels in commonly consumed cheese in Lebanon should be regularly done. It also shows an alarming situation with respect to cheeses produced from local small farms.