Depends–I maintain eating any part of a millionaire is vegan, but a normal person has to consent to giving you their boogs for them to be vegan. Most non-human animals can’t consent, except like parrots and magpies, but I’m not sure they even make boogs, (I don’t know much about avian respiration)
It’s also worth considering if those boogs are just gonna be thrown away–even if it’s not strictly consensual or outright goes against the wishes of the producer, I go back and forth on whether it’s ethical to consume a discarded, or “dumpster” booger