cigarette nicotine levels have increased?

[angus]

I had an undergraduate physical chemistry professor who did a postdoc at the Phillip Morris tobacco company.  It was a fun job he said.  They'd sneak into the production plant and smoke the twelve foot long cigarettes before those were cut into the one hundred millimeter cigarettes for packaging.  Anyway, one thing he told us was that cigarette companies had the production pretty well down by then.  They'd extract all the polar and nonpolar compounds out of the tobacco via normal industrial-scale extraction techniques, leaving behind a big vat of colorless, clear limp cellulose, then go back in with carefully controlled amounts of tannins, tar, and nicotine.  No doubt the goal was to create a cigarette with much greater amounts of nicotine than would naturally occur in the leaves of tobacco plants.  There are, of course, less technologically advanced ways of getting your plants to produce certain chemicals.  I've found that poking and cutting at the roots of cannabis plants causes them to produce greater amounts of THC than would occur in a plant in a less hostile environment, thus apparently THC is probably produced as a reaction to stress, but if you're making cigarettes on a large scale you don't want to depend on evolution or the gods or mother nature.  Nowadays you can pretty much make a cigarette contain whatever you want it to contain.  And more nicotine is a guarantor of repeat customers.  Better living through chemistry.