I mean, if the stuff that was in the pipe I cleaned last night was also in my lungs I’m not sure how it can’t be damaging on some level. It’s like gooey asphalt.
I mentioned in another thread that a guy I know who smoked all his life (but never tobacco) has copd and his docs were asking him 30 years ago if he smoked (tobacco) because his lungs were jacked up even back then.