Sitting somewhere when a cloud of cotton candy vapor washes over you? If you can smell the sweet scent of a vape, that's not a great sign. Does Vaping Smell? and How to Tell if Someone Is Vaping Ultra Liquid Labs Just like footprints you leave behind, smoke and vape leave traces too. On your clothes. In your home. In the air your family breathes. The smell may fade, but the harmful residue In secondhand vape, scientists smell risk American Heart Association