Attempts to reduce the known or suspected risks to health from tobacco use by modifying tobacco or cigarettes predate the first U.S. Surgeon General’s report on smoking and health. One of the first product innovations introduced with the potential and promise of harm reduction was filters. Filters reduce the amount of toxicants that go into the smoke inhaled by a smoker. The sale of filter cigarettes went from 1% of the market in 1952 to more than half of the market by 1960 (U.S. DHHS, 1989). In 1998, 98% of cigarettes sold in the United States contained filters (FTC, 2000).
The next major product modification with safety implications was the introduction of “low-yield” cigarettes. These products emit lower tar, carbon monoxide (CO), and nicotine than other products as measured by the Federal Trade Commission (FTC) assay (the “smoking machine”). This is achieved through blending different types of tobacco, ventilation, addition of accelerants, and filtration, as discussed in Chapter 4. The utility, purpose, and inferences made of the FTC assay yields are discussed in Chapters 4 and 11.
Consumers believed, and still do, that these products pose less risk to health than other cigarettes. Typical advertising campaigns for low-yield products stressed the softer side of smoking: “For smokers who prefer the lighter taste of a low-tar cigarette” (Kluger, 1997). An advertisement in the mid-1970s for a low-yield product, True, stated, “Considering all I’d heard, I decided to either quit or smoke True. I smoke True” (Pollay and Dewhirst, 2000). The market share of products yielding 15 mg of tar or less (as measured by the FTC assay) increased from 4% in 1970 to more than 50% in 1981. These products commanded approximately 80% of the U.S. cigarette market in 1998 (FTC, 2000).
Data on the health impact of low-yield products are conflicting, in part due to a lack of systematic and comprehensive study early in the introduction of these products. Most current assessments of the epidemiological and toxicological data suggest, however, that low-yield products are associated with far less health benefit than predicted based on FTC assay-generated tar, CO, and nicotine levels. The sales-weighted average of tar and nicotine yields of cigarettes in the United States has decreased by approximately half since the 1950s (Health Canada, 1998), without a significant or proportional change in the harm or prevalence of specific smoking-related diseases. Some of this is explained by changes in smoking behavior, known as compensatory smoking. In an effort to maintain adequate exposure to nicotine, smokers who use low-yield products smoke differently (e.g, inhale more deeply) than those who smoke higher-yield products. Thus, exposure to tobacco toxicants from low-yield products is