The History of Cigarettes. Changes in Smoke Chemistry or Modern Day Cigarettes
This 38-page document from 1983 traces the history of modern cigarette design and construction back to the Aztecs. Page 34 contains information comparing the makeup of cigarettes from the 1940s with those of the 1980s.
ln 1940, a commercial cigarette contained 1300 milligrams (mg) of tobacco by weight, and by the 1980s it contained only 750 mg of tobacco. The author states,
- "Thus, a cigarette of the 1980's would contain about 40% less tobacco... than its counterpart of 40 years ago."
Apparently, early in the 1900s cigarette makers used just the upper one-fourth of the tobacco leaf. Over the years, though, mechanical threshing created increased waste, and labor costs kept increasing. Eventually, the industry found ways to make use of parts of the tobacco plant that were never initially intended for use, like stems. They developed ways to incorporate stems by making fillers like reconstituted and "puffed" tobacco (puffed tobacco is treated with a gas to expand it, as in Dry Ice Expanded Tobacco or DIET tobaccco). In the long run, these cost-saving measures, combined with the use of additives, have decreased the amount of actual tobacco in a cigarette by fully 40%. 
- Vello Norman, Lorillard Tobacco Company The History of Cigarettes. Changes of Smoke Chemistry of Modern Day Cigarettes May 4, 1983. 38 pp. Bates No.89442789/2826
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