Peanut Day

What the day is

Peanut Day is observed on September 13. The other peanut entries in this calendar cover the plant, the confectionery and the allergy research; this one is about why peanuts are among the most heavily tested crops in the food supply.

Origin and background

In 1960 turkeys on English farms began dying in enormous numbers, more than 100,000 of them, from a disease nobody could identify and which was initially called Turkey X disease. Investigators traced it to a shipment of peanut meal used in feed, and from that meal isolated toxins produced by a mold of the genus Aspergillus. They were named aflatoxins, after the organism.

They turned out to be among the most potent liver carcinogens known, and the discovery reshaped food safety. Peanuts are especially vulnerable because they develop underground in warm, humid soil, which suits the mold, and the risk rises when the crop is drought-stressed or dried too slowly after lifting. Contamination is also uneven: a single badly affected nut can sit among thousands of sound ones, which makes sampling a statistical exercise rather than a simple test.

The response is one of the more rigorous systems in agriculture. Lots are sampled at multiple points, electronic and hand sorting remove damaged and discolored nuts, and legal limits are set very low. The controls are strict enough that aflatoxin exposure from peanuts is a minor concern in countries with enforced standards, and remains a serious public health problem in places without them, where it is associated with liver cancer and with stunted growth in children.

The practical consumer version is simple. Discard any nut that is shrivelled, discolored or musty rather than eating around it, and do not keep shelled nuts warm and damp.

How to take part

• Throw out nuts that look shrivelled or smell musty. Do not sort and eat the rest.
• Store shelled peanuts cool and dry, or refrigerate them.
• Buy from brands large enough to be testing systematically.
• Read about the 1960 outbreak, which changed food safety well beyond peanuts.