you forgot to quote this part "Maintaining respiration and circulation is the most important aspect of treatment"..
i find that interesting because nicotine causes vascular constriction in small doses, thus limiting circulation.
I was more interested in "Any substance that impairs health or destroys life when ingested, inhaled, or absorbed by the body in relatively small amounts." and "Some toxicologists suggest that, depending on the dose, all substances are poisons." and "Many experts state that it is impossible to categorize any chemical as either safe or toxic and that the real concern is the risk or hazard associated with the use of any substance."
It seems to me that even the professionals disagree on exactly how to classify substances as poison, or even if it has any validity.
But that's just me.
Carry on