This thread seems to have switched from sweating to smoking.
I will just add my opinion to the people that say that detecting a smoker by smell is no problem, no matter how well dressed, coifed or washed. My office is on Indian reserve land and many native offices are located here. I assure you that riding up in the elevator leaves one in no uncertainty about whether you are among smokers, and you also can tell which one is the smoker.
Sadly, "rates of cigarette smoking among natives are much higher than in non-aboriginal populations. The Canadian Medical Association estimates that fully one half of natives overall smoke, and a shocking four out of five adolescents aged 15-19. The CMA notes that, even as associated rates of cardiovascular disease are declining in North America, among aboriginal populations they’re sharply increasing." (from an aboriginal people's source).
Similarly, I keep a sweatshirt just for blowing the driveway and mowing the lawn. The smell of exhaust (2 stroke seems worst) permeates the fabric just the way that cigarette smoke does.
Interestingly, when I used to live in a house with all wood rough finish (cedar) walls, when someone had been smoking (even me, for the odd cigar) the smell disappeared by the next day. In a conventional painted interior, it will last for days. Hmm.
