Milk is a staple food that is essential for human nutrition because of its high nutrient content and health benefits. However, it is susceptible to being contaminated by Aflatoxin M1 (AFM1), which is a toxic metabolite of Aflatoxin B1 (AFB1) presented in cow feeds. This research investigated AFM1 in Tunisian raw cow milk samples. A total of 122 samples were collected at random from two different regions in 2022 (Beja and Mahdia). AFM1 was extracted from milk using the QuEChERS method, and contamination amounts were determined using liquid chromatography (HPLC) coupled with fluorescence detection (FD). Good recoveries were shown with intra-day and inter-day precisions of 97 and 103%, respectively, and detection and quantification levels of 0.003 and 0.01 µg/L, respectively. AFM1 was found in 97.54% of the samples, with amounts varying from values below the LOQ to 197.37 µg/L. Lower AFM1 was observed in Mahdia (mean: 39.37 µg/L), respectively. In positive samples, all AFM1 concentrations exceeded the EU maximum permitted level (0.050 µg/L) for AFM1 in milk. In Tunisia, a maximum permitted level for AFM1 in milk and milk products has not been established. The risk assessment of AFM1 was also determined. Briefly, the estimated intake amount of AFM1 by Tunisian adults through raw cow milk consumption was 0.032 µg/kg body weight/day. The Margin of Exposure (MOE) values obtained were lower than 10,000. According to the findings, controls as well as the establishment of regulations for AFM1 in milk are required in Tunisia.
Keywords: HPLC-FD; Tunisia; aflatoxin M1; raw cow milk samples; risk assessment.