You make my point for me. Look at how much effort and expense they have to go to just for those bomb sniffing machines - and they basically can track only a sma

You make my point for me. Look at how much effort and expense they have to go to just for those bomb sniffing machines - and they basically can track only a small handful of very specific, very rarely found chemicals. Implementing this to sort through things like deodorants and skin flakes is way more complex. You are dealing with organic molecules, for starters. And there are billions of different combinations of airborn bacteria and viruses and stuff that make up the smell of a person.