No, this is not a post about Superman. Megalopolis was in Arcadia and it had a Temple to Aset (Isis), Sarapis and Anubis. There is a text associated with purity in that temple.
Most of these rules were how long you had to stay away from the temple after certain events and most of them had to do with women.
Obviously, some of these are more feasible to follow today than others.
After childbirth, 9 days
After abortion, 44 days
After menses, 7 days
After sex, clean with water from head to toe, same day.
After bloodshed, 3 days
After eating goats or sheep, 3 days
After eating other foods, clean with water from head to toe, same day.
Source
Bricault, Laurent. Les Cultes Isiaques Dans Le Monde Greco-romain (La Roue a Livres / Documents Book 66). (Les Belles Lettres, 2013), 363-364 and 365-366.