Aflatoxin M1 in milk: A global occurrence, intake, & exposure assessment

Abstract

BackgroundAflatoxin B1 (AFB1), a naturally occurring mycotoxin (fungal toxin) in maize and nuts, causes liver cancer and has been associated with other adverse health effects. Much less is known about the toxicity of its metabolite AFM1, which is secreted in the milk of mammals. Nonetheless, many nations have set regulatory limits for maximum allowable AFM1 in milk and other dairy products. Scope and approachWe collected comprehensive data on the occurrence of AFM1 in samples of milk worldwide, encompassing a wide range of different milk types: raw, pasteurized, ultra-high-temperature treated, fresh, and powdered. For each nation, we found average daily milk intake based on national or global dietary surveys. We then used the AFM1 concentration data and intake rates to calculate AFM1 exposure for adults in multiple nations worldwide. Key findings and conclusionsSeveral nations including Pakistan, India, and several sub-Saharan African nations, had AFM1 levels in milk that substantially exceeded United States and European Union regulatory limits for AFM1, indicating potential risk to individuals in those nations with high milk consumption. Because no regulatory agency has set a tolerable daily intake (TDI) for AFM1, we could not compare our exposure estimates to a TDI to determine at-risk populations. But importantly, high AFM1 levels in milk indicate high levels of AFB1 in animal feed. This may imply that the crops used to make that feed such as maize, may have high AFB1 levels, which upon consumption could harm both animal and human health.