How long does it take for the nicotine of one cigarette to leave your body?

Each cigarette . Contains about 1 mg of nicotine, and its half-life is about 2 hrs. It also is multicompartmental, meaning it can be "accumulated" in adipose tissue, detoxified to cotinine by cytochrome p-450 enzymes, so eliminaion entrely can be complicated by the direct half life, and then the leeching from the fat cells. It's complicated!