Aflatoxins

Aflatoxins are a group of mycotoxins produced primarily by certain species of Aspergillus, notably A. flavus and A. parasiticus. They commonly contaminate staple crops such as maize, peanuts, cottonseed, and tree nuts, especially in warm, humid regions. Aflatoxin B1 is the most toxic and carcinogenic member of the group, but several other compounds (B2, G1, G2) can occur in contaminated food as well.

Health effects of aflatoxins vary with dose and duration of exposure. Chronic exposure to aflatoxin B1 is a well-established risk factor for hepatocellular carcinoma, with a mechanism involving metabolic activation to reactive epoxides that form DNA adducts and drive mutations, including in the p53 gene. Acute exposure can cause aflatoxicosis, characterized by liver failure and possibly death. The risk is higher in individuals with concurrent hepatitis B or C infection and in settings with high dietary exposure.

Regulation and risk management aim to minimize human and animal exposure. Jurisdictions set limits on total aflatoxins in foods and feeds, often distinguishing B1, B2, G1, and G2; international bodies provide guidance on acceptable intake levels. Prevention focuses on agricultural practices, crop drying and storage, and rapid removal of visibly contaminated material. Some processing methods do not reliably destroy aflatoxins, though certain treatments can reduce levels; in animal feeds, adsorbent materials may lessen bioavailability. Detection methods include HPLC or LC-MS/MS, as well as immunoassays, used in monitoring programs.

Control relies on a combination of good agricultural and manufacturing practices, regular testing, and rapid response to contamination to protect food safety and public health.