Humans vary in their susceptibility; only one in four people who consumed quail soup containing the toxin fell ill.

The Bible (Numbers 11:31-34) mentions an incident where the Israelites became ill after having consumed large amounts of quail in Sinai.

Aristotle (On Plants 820:6-7), Philo (Geoponics: 14: 24), Lucretius (On the Nature of Things: 4: 639–640), Galen (De Temperamentis: 3:4) and Sextus Empiricus (Outlines of Pyrrhonism: 1: 57) all make this point.

Central to these ancient accounts is the idea that quail became toxic to humans after consuming seeds from hellebore or henbane (Hyoscyamus niger).

However Sextus Empiricus suggested that quail ate hemlock (Conium maculatum), an idea revived in the 20th century.