Nicotine contributes nearly all the alkaloid content of tobacco plants. Historically, human exposures were associated with smoking, chewing, or sniffing various forms of tobacco, and abundant literature details the adverse effects of chronic exposures to these tobacco products. Less attention has been given, however, to understanding the specific role nicotine plays in these adverse outcomes. Although recognized to possess potent pharmacological and addictive properties, nicotine is now delivered in electronic cigarettes and is a common ingredient in over-the-counter products designed to reduce or stop smoking, including gum and dermal patches.
