Mycotoxins: An ongoing challenge to food safety and security

Mycotoxins are poisons that some moulds produce on crops, in the field and in storage. They have shaped history. Ergot on rye caused the "St Anthony's fire" epidemics of medieval Europe, and in 1960 contaminated peanut meal killed more than 100,000 turkeys in the United Kingdom, which led to the discovery of aflatoxins.

More than 400 mycotoxins are known, but only a few are regulated. An estimated 60 to 80% of food contains detectable amounts, often several toxins together. The World Health Organization estimates that more than half a billion people, most of them in developing regions such as sub-Saharan Africa, are regularly exposed to harmful levels. Aflatoxins may be behind up to 155,000 cases of liver cancer a year, and contaminated feed harms the growth, fertility and immunity of farm animals.

Climate change is moving the problem around. Heavier rain in northern Europe has raised mould toxins in wheat, while warmer weather in southern Europe favours aflatoxin in maize. In South Africa, diseased maize often carries several toxins at once.

Why it matters: this review in PLOS Pathogens finds no single fix. The authors call for action along the whole food chain: good farming practice, proper drying and storage, faster testing, and joint work between agriculture, veterinary and public health services, an approach known as One Health.