Aflatoxin M1 in raw cow milk and associated hepatocellular carcinoma risk among dairy farming households in Malawi

In the present study, a total of 112 raw milk samples were collected between October and December of 2018 from dairy farming households in Malawi and analyzed for aflatoxin M1 (AFM1) using VICAM aflatest fluorometry procedure. These data together with the consumption data obtained through a milk consumption frequency questionnaire were used for the calculation of AFM1 exposure and its association with hepatocarcinoma (HCC) risk in dairy farming population. Average daily milk intake by children and adults were approximately 300 ± 0.07 and 541.7 ± 0.14 mL, respectively. All raw milk samples tested positive to AFM1 averaging 0.551 μg/L. Probable mean daily exposure to AFM1 for adults was 4.98 ± 7.25 ng/kg BW/day almost half that of children (8.28 ± 11.82 ng/kg BW/day). Estimated risk of AFM1-induced HCC associated with consumption of milk among children and adults were 0.038 and 0.023 cases per 100,000 individuals per year, respectively. Although the results of this investigation suggest a low risk of HCC, other negative health effects of AFM1 justify its continuous monitoring and update of the risk assessment. This work presents the first insight in the occurrence of AFM1 in cow milk in Malawi as well as associated AFM1 exposure in dairy farming population.