I was outside the other day standing alongside my house shielded by the wind when from out of nowhere a faint smell passed by. I have no idea where it came from or what generated it. Did not smell like nature. I assume some of the molecules would "stick" to my clothing. I see a lot of videos where scientists produce vapors and smells and consequently I would think the molecules would collect in clothing. This may seem like a stupid question, but do those molecules break down or are they carried away, say in the laundry? How do we know if they are harmful?