Or maybe the artist was inspired by the connection of the Phrygian cap with psychedelic "liberty cap" mushrooms (Psilocybe semilanceata), which are distributed widely across Europe and associated with elves, fairies and various other wee folk?
I assume they have some method of keeping snails, woodpeckers and other animals resistant to the poison at bay.
While liver damage is mitigated by the fact that the organ in question regenerates, nerves don't.