When surgeons scrub before operating, they remove or kill many of the bacteria on the surface of their skin. But the more they scrub, the more they dredge up new bacteria from within the epithelium, so there is a point of diminishing returns. How Animals Smell the Goat Scientific research on the ability of wild animals to detect odors is minimal. But a good bit of work has been done on the dog's sniffer, because dogs can be taught to respond to olfactory stimuli and because search and rescue people and the DEA guys at the Miami Airport are interested in how well dogs smell. From their findings we can extrapolate, to a degree, what a deer or bear might smell and how they might smell it.
Dogs detect scent that is carried on thermal currents and scent that is on the ground.
The airborne scent is comprised primarily of volatile molecules of aliphatic acids. A dog can detect concentrations as low as one part in 10 quadrillion. Secondarily, we produce a ground scent downwind of where we walk, a trail of smell created by our constantly shedding scurf and its bacterial hitchhikers. A variety of products on the market purport to minimize, even eliminate, a hunter's scent. In other words, nothing eliminates scent.