Sex with someone on meth?

Weird question. I have always been totally drug free. But fun nice conversations with this guy I’m about to hookup with have me nervous now. He said full disclosure, he was smoking and lit asf right now. I assume he means meth. Yuck.

I would still go through with it, but I’m wondering, if he gives me head or we kiss, does his saliva contain meth as well? Would I possibly get a small dose? I’m uncut as well. More sensitive.

Feel bad as I’ve already committed to a meetup. Hate to ghost him, but I’m not interested in getting any dose of drugs.