Cigarette smoking during anxiety-provoking and monotonous tasks
Approximately 99% of tobacco-based nicotine is the molecule S-nicotine, but synthetic nicotine contains equal amounts of S-nicotine and R-nicotine, a mirror molecule scientists know very little about
Strong floral odours can have a similar effect, but professional bee keepers have generally stayed with smoke, perhaps because they have more experience with it, and possibly also because it's cheaper
Nat Rev Cancer (2014) 14:41929.10.1038/nrc3725 70 CaoCChenJLyuCYuJZhaoWWangYet alBioinformatics analysis of the effects of tobacco smoke on gene expression
The exact cause of HS is unknown
If this was something that happened, every child with a cold sore would have spread it to their hands, or other places on their body