Occurrence of aflatoxin M1 in yogurt and milk in central-eastern China and the risk of exposure in milk consumers

We investigated the occurrence of aflatoxin M1 (AFM1) in yogurt and milk, including pasteurized, ultra-high temperature (UHT), and extended shelf life (ESL) milk samples, from central-eastern China and assessed the risk of AFM1 exposure in consumers. We collected 845 milk samples, consisting of yogurt (329), pasteurized milk (288), ESL milk (120), and UHT milk (108) from Hubei, Zhejiang, and Fujian provinces during winter season. The AFM1 levels in milk samples were determined using a validated enzyme-linked immunosorbent assay method. We detected AFM1 in 194 yogurt samples (59.0%) and 427 milk samples (82.8%). Four yogurt samples (1.2%) and 14 milk samples (2.7%) exceeded the European Union legal limit (50 ng/L) but were below the Chinese legal limit (500 ng/L). AFM1 concentration was lower in UHT milk than that in ESL and pasteurized milk (p < 0.05). Infants between 2 and 3 years of age had the highest risk of AFM1 exposure, with the estimated daily intake of 0.25 and 0.23 ng/kg bw/day for male and female groups, respectively. Therefore, AFM1 contamination in milk products should be monitored and reduced to lower levels, given the high prevalence and the risk of AFM1 exposure in infants.