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tobacco
tobacco Tobacco contains nicotine, an addictive substance that enters the body quickly through the lungs and mucous membranes and reaches the brain very rapidly when smoked.
Tobacco contains nicotine, an addictive substance that enters the body quickly through the lungs and mucous membranes and reaches the brain very rapidly when smoked. In the liver, most nicotine is changed into cotinine, a longer-lasting compound commonly used as a biological indicator of tobacco exposure.