In 1979, a catering error led to 78 schoolchildren being poisoned by their old friend, the potato.
Having recently returned to a school in South London following a holiday, a large number of boys suddenly fell ill with symptoms from vomiting and diarrhea, to fever, and even becoming comatose, depression of the nervous system, and, in the most serious cases, "episodes of convulsive twitching".
"These boys also showed signs of peripheral, circulatory collapse, even when dehydration was only slight," doctors wrote in a BMJ Case report published the same year. They reported that "little" blood was lost in the stool or vomit of the boys, despite the six days that symptoms continued in some of them.
The cause of the illness was quickly identified: they had all eaten boiled potatoes some 14 hours previously.
"Potatoes are such a common feature of the Western diet that most people are surprised to learn that they are the produce of a poisonous plant," the team wrote. "In fact, potato stems and leaves contain a series of alkaloidal glycosides, termed solanines, which are highly toxic."
They cite other cases, including one man who was poisoned after deciding to use the leaves and shoots of potatoes as a vegetable in their own right.
The main hazard, however, comes from eating potatoes after they have turned green, which happened here because the caterers had used a bag of potatoes leftover from the previous term. Thankfully, they all recovered following treatment in hospital, though some of them had a rough time and hallucinated during their stay.
"Greening and sprouting occur when potato tubers are exposed to light or are stored in adverse conditions, and these processes are associated with the production of the alkaloids. Initially, this occurs at the sites of increased metabolic activity, such as the "eyes"; but eventually, solanines can be detected in the flesh of the tuber," the team explained in their paper.
"Fortunately, few people cook greened or sprouted potatoes because of their appearance and their bitter, unpleasant taste; so that in practice solanine poisoning appears to be rare except in times of food shortage."