I'm having problems following the threads on this, so I'll just plop this information in. Still dopey from knee surgery.
Galina Krasskova is a polytheistic reconstructionist with some interesting points of view. She has written quite a bit about miasma in ancient religion -- and is rather scornful the modern neopagan tendency to see everything as rainbows and unicorn. So you might like to check her blog both for her thoughts and for sources. She is also an artist who creates lovely prayer cards for various deities.

Rita