Is Tobacco Using the Main Cause for Lung Diseases Questions

Most of the cancer-causing substances in smoke are in tar, which is the materialthat remains after cigarette smoke is passed through a filter. A cigarette typically con- tains 0.3 mg to 2.0 mg of nicotine (cigars yield 9 to 12 times more). When cigarettes are smoked and inhaled, about 20% of the nicotine is absorbed, compared with 2.5% to 5% when smoke is drawn into the mouth and then exhaled. That virtually all ciga- rette smokers inhale is one reason (other than sheer numbers) that cigarette smoking, as opposed to cigar or pipe smoking (cigar and pipe smokers tend to inhale to a lesser degree), is the major cause of diseases related to tobacco use.

Because of the importance of the tar and nicotine content of cigarettes, until the mid-1980s, the Federal Trade Commission (FTC) published statistics on the tar and nicotine yield of cigarette brands manufactured in the United States. The FTC used to conduct its own yield tests by using smoking machines; today, tobacco compa- nies report the results of the same kind of tests, which the FTC requires them to do (Cotton, 1993).

The amount of tar and nicotine delivered in U.S. brand-name cigarettes has declined considerably. In 1968, the average tar and nicotine yields of cigarettes pro- duced in the United States were 21.6 mg and 1.35 mg, respectively. In 1978, these contents were 16.1 mg and 1.11 mg; in 1988, they were 13.3 mg and 0.94 mg; and in 1998, 12.0 mg and 0.88 mg (Federal Trade Commission, 2001). These averages cover a range of values for “light” versus “regular” versus “ultra” brands. For exam- ple, according to a report published by the Lorillard Tobacco Company in February 2009, each Newport Lights Box 80s cigarette has 9.0 mg of tar and 0.80 mg of nico- tine, each Newport Medium Box 80s cigarette has 12.0 mg of tar and 1.00 mg of nicotine, and each Newport Regular Box 80s cigarette has 18.0 mg of tar and 1.30 mg of nicotine. A similar range is evident in cigarettes manufactured in other coun- tries. For example, Endo et al. (2009) reported the tar and nicotine levels of the 10 most popular cigarette brands in Japan. The tar and nicotine levels were determined by following the testing procedures of the International Organization for Standard- ization (ISO), whose protocol is aligned with that of the FTC. (It is interesting to note that Canadian cigarette brands published tar and nicotine levels according to a far stricter protocol called “Health Canada Intense” that results in considerably higher estimates of tar and nicotine levels than those of either the FTC or the ISO.) The findings for the Japanese brands ranged from 0.90 mg of tar and 0.20 mg of nicotine for each “Pianissimo” cigarette, to 14.80 mg of tar and 1.11 mg of nicotine for each “Seven Stars” cigarette.