Aflatoxins are toxic mycotoxins produced by certain moulds, primarily Aspergillus flavus and Aspergillus parasiticus, which are commonly found in soil and on crops. These toxins frequently contaminate agricultural commodities such as grains, nuts, and animal feed, posing a significant risk to both food safety and public health. Among the various types, aflatoxins B1, B2, G1, G2, and M1 are considered the most important from a regulatory and toxicological perspective.
When dairy animals, particularly cows, consume feed contaminated with aflatoxin B1, it is metabolised in the liver and converted into Aflatoxin M1. This compound is then excreted in the milk, creating a pathway for contamination in dairy products such as milk, cheese, and yoghurt. As a result, even if the original contamination occurs in feed, it can ultimately reach human consumers through commonly consumed foods.
A key concern with aflatoxin M1 is its stability. Standard milk processing techniques, including pasteurisation, do not effectively eliminate this toxin. Consequently, if aflatoxin M1 is present in raw milk, it may persist through processing and remain in the final product, increasing the risk of dietary exposure.
From a health perspective, aflatoxins are associated with a wide range of adverse effects. They are known to be hepatotoxic, genotoxic, and carcinogenic, with long-term exposure linked to liver cancer. Additional risks include kidney and liver damage, immune system suppression, and potential reproductive and gastrointestinal issues. Due to these serious health implications, strict monitoring and control measures are essential to minimise aflatoxin contamination in the food chain and reduce overall exposure.