OOH get her!
Firstly, what's Grade School? If you mean University then yes thatÂs where much of that comes from though not a smoking cessation lecture, probably a biochemistry though possibly a histology or epidemiology one.
Secondly, in addition to what can only be described as a flippant and unhelpful tone of your response, while I am no expert, there are factual inaccuracies contained within it: -
While nicotine has not been shown to be greatly carcinogenic, Nicotine and Carbon Monoxide are the primary causes of cardiovascular disease for the tobacco smoker, Nicotine (alone) the primary cause of heart disease for chewers/snuff users (assuming the heart disease in either case is smoking related rather than genetic). Nicotine feeding (to monkeys) has been shown to increase the concentration of low-density lipoproteins in the blood (Cluette-Brown et al. 1986) a profile linked to arteriosclerosis in humans. Nicotine has also been shown to have an impact on platelet production, increasing the risk of blood clots (Renaud et al. 1984). In addition the action of Nicotine has been shown to increase the number of endothelial cells in the blood serum in vivo and to cause increased mitotic activity (cell generation by division) in vitro pointing to direct damage to these tissues from nicotine. The links between nicotineÂs action on the sympathetic and para-sympathetic nervous system and its impact on cardiac health continue to be investigated (I came across a research opportunity for a neurologist/biochemist in the States, Texas I think, while looking for info on topical effects prior to my initial question) Vasoconstriction is another by-product of nicotine as is interference with normal wound healing and epithelialisation Â no good at all when the tickerÂs hammering away at ten to the dozen after a nicotine rush (nicotine also cause tachycardia, so makes acute cardiac problems worse as well as causing chronic ones). Perhaps not as dramatic as some animal toxins but getting on for being on Â*par with something like strychnine. Felt sad in Selfidges as I passed the tobacco stall, missed it - after writing this down I'm fairly glad I remained on the wagon (fagwise) while in the pub tonight!
While nicotine is water-soluble and this acts as a means of extraction (for the living plant too Â look up tobacco croppersÂ disease and Green Tobacco Syndrome) it is not its solubility in water that makes it a potential contact poison (an old fashioned and non Âtechnical term I know) most larger chemicals that are readily absorbed through the skin are more lipid-soluble (organophosphates, PCBs, oestrogen, fentanyl, nicotine etc) We are pretty waterproof, good job otherwise weÂd leech out a lot of vital nutrients in the bath. ItÂs also why you have to put some more water-soluble chemicals on a mucus membrane (mouth, stomach eyelid or up the chuff) in order to absorb them. Look in any textbook with a section on pharmotaxis.
The primary mechanism for carcinogenesis in the mouths of tobacco chewers is the action of tobacco specific nitrosamines N-nitrosamine (TSNA), N'-nitrosonornicotine (NNN), and 4(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) (some complex aromatics are produced, I believe, as part of the curing process so combustion is not required this is indicated in some studies from Malaysia - their curing processes might be different obviously.) These are shown to cause mutation in the gene P53 (among others), the associated protein p53 is intimately involved in the cell lifecycle commencing the process that leads to cell death. This has been demonstrated (along with the mutation of gene P16 in a significant subset of oral cancer in chewers and smokers) A single mutation creates a pre-cancerous cell one that is highly predisposed to become malignant on a second mutation (either from the same source or other environmental factors such as other carcinogenic chemicals or even some viruses)
Thirdly, while I have no proof, IÂve never chewed tobacco, and canÂt be bothered to do any research on it I canÂt believe that no nicotine rich saliva finds its way down the gullet either on the initial chew or when the wad of tobacco is stuck between the gum and cheek, or gum and lip.
Fourthly, you are possibly right about the fragrance at such concentrations, but that might be a matter for experiment (bluebell only works at concentrations below 0.1%)
Fifthly, Bitchy and right is OK (if a little rude to the sensitive Britisher), bitchy and funny is great, bitchy and dull is tedious, and bitchy, dull and wrong is unforgivable. Â*:-*