Topic: Backyard pizza ovens

[Peripatetic Phil]

Soot was once used for cleaning one's teeth, so unlikely to be a risk there; as to ash, whilst I have a morbid fear of cigarette ash in my food, I don't think I'd   worry about the odd hardwood flake sticking to the cheese, although if it were so thick that I couldn't see the cheese I would probably prefer not to eat the pizza unless I were starving.  Ash was traditionally added to cheese to help preserve it, grow the proper mould, and make a rind. You can still find cheeses with ash in them (even in Waitrose !), tho' I personally don't like them.