potentially result in reduced exposure to toxicants. The committee uses “potentially,” because whether exposure to tobacco toxicants is reduced depends on the user’s behavior, such as frequency and intensity of use. Reduced exposure, however, does not necessarily assure reduced risk to the user or reduced harm to the population. Therefore, and in order to avoid misinterpretation, the committee will use the generic phrase “potential reduced-exposure products,” or PREPs, when discussing modified tobacco products, cigarette-like products (whether tobacco containing or not), or pharmaceutical products and medical devices (whether nicotine containing or not) developed for their tobacco harm reduction potential. Demonstration of exposure reduction is possible but at this time, demonstration of harm reduction is not. This conclusion is reiterated and supported in subsequent chapters.
No tobacco-based PREPs other than conventional low-yield products have been used by enough consumers to assess health impact. The recent or forthcoming expansion of the test market for several new products, which are described in Chapter 4, and public statements by tobacco company executives suggest a new and critical opportunity for assessing harm reduction. The next few years may see an explosion of available tobacco or cigarette-like products that make some claim of harm reduction based on reduced tobacco or smoke content of one or more toxicants.
Uncertainty and skepticism remains about the potential health benefits of PREPs. Key to the skepticism, in addition to the lessons learned from low-yield products, is concern that such products will discourage quitting in smokers who might otherwise have stopped using tobacco or will encourage new tobacco use. Evidence to support this concern is limited, however. Historical data suggest that people “switched down” to low-yield products due in part to health concerns, but the studies were not designed to determine whether those smokers would have quit tobacco use altogether had only high-yield products been available. Most PREPs will maintain nicotine addiction and there is little agreement in the tobacco control field that public policy should encourage products that maintain nicotine addiction. Worrisome as harm reduction might be to those who have studied the history and disappointments of low-yield cigarettes, PREPs are currently available and likely are here to stay.
There is disagreement among tobacco control experts about the optimal content of nicotine in tobacco products. Whether nicotine addiction is harmful beyond supporting tobacco use and should, therefore, be the target of public health efforts is not a simple question. Nicotine has toxic properties (see Chapter 9), but they are far fewer and less serious than