It was a part of our safety training in the sixties, that if a female passenger was to be administered oxygen, her lips must first be thoroughly cleaned of lipstick (Men didn't wear lipstick in those days, well, not many). The reason was that in those times, lipstick contained Petroleum Jelly, and there was a significant risk of severe lip burns.
Petroleum Jelly is no longer a base for modern lipstick (or so I'm told).
Regards,
Old Smokey