Cigarettes are the major form of smoked tobacco. Prevention includes stopping smoking or chewing tobacco. Protonated nicotine lacks the harshness of tobacco smoke. Cancer is caused by inhaling carcinogenic substances in tobacco smoke. Another is the control of tobacco smoking. An example is on the study of smoking tobacco on human health. Lucky Strike is an American brand of cigarettes owned by the British American Tobacco group. This tar is chemically similar to that found in tobacco smoke or cigars. Risk factors include tobacco and alcohol use. Butanone is a constituent of tobacco smoke. Copper is a constituent of tobacco smoke. Ammonia is a constituent of tobacco smoke. Excise taxes are levied on alcohol, tobacco, and motor fuel. Cobalt is also a constituent of tobacco smoke. This association is independent of tobacco and alcohol use.