Sidestream Smoke

Sidestream Smoke and ‘Safer’ Cigarettes

By Michael A. Dubick and Stephanie E. Dubick

At least two centuries have passed since it was first formally suggested in the West that tobacco-product use might adversely affect human health. And within the last 50 years, correlations of cigarette smoking and various diseases have been validated. Yet according to statistics the Centers for Disease Control and Prevention published in 1997, approximately 25 percent of American adults smoke. There has been a downward trend of numbers of smokers in the United States over 20 years, but this trend apparently has hit a plateau, perhaps because of increases in the ranks of adolescent smokers.

This apparent stability is why the U.S. Surgeon General’s office has set the goal of reducing the number of adult smokers in the country to 12 percent of American adults by 2010.

Smoking will continue to affect all Americans for the foreseeable future—indirectly, through its economic impact on American healthcare, and/or directly, through purposeful smoking or through proximity to persons who are smoking (as in public places and at home). Research of the last 20 years has shown that interactions with persons smoking cigarettes may impact the health of nonsmokers (herein, “nonsmokers” refers to persons who do not purposely smoke) by exposing them to sidestream smoke. It is accepted that acute exposure to sidestream smoke can irritate the eyes, nose, throat, and lungs and can induce cough and headache. Much less widely perceived are other, graver possible consequences of exposure to sidestream smoke. In a special report, the U.S. Environmental Protection Agency suggested that long-term exposure to sidestream smoke may be responsible for the deaths of as many as 53,000 nonsmokers per year. In another report, the International Agency for Research on Cancer stated that exposure to sidestream smoke increases nonsmokers’ risk of developing cancer by 16 percent.

Findings from research on sidestream smoke are controversial. Study data suggest that sidestream smoke may be particularly detrimental to newborns and other children and even to fetuses. There is an association of sidestream smoke exposure and an elevated incidence among children both of asthma and of infections of the lower respiratory tract. In other studies, researchers have found that sidestream smoke adversely affected lung function in young nonsmokers, can induce carbon monoxide poisoning, and may contribute to increases in the incidence of cardiovascular disease.

Studies have shown that sidestream smoke from cigarettes is at least as toxic as smoke inhaled directly from cigarettes. There is no scientific evidence of a threshold of harm from exposure to sidestream smoke, and freshness is not essential to its injuriousness. According to environmental studies, carbon monoxide is in stale cigarette smoke at its concentrations in fresh cigarette smoke. There also may be no difference between concentrations of carbon dioxide and nicotine in stale cigarette smoke and such concentrations in fresh cigarette smoke. Researchers have found that stale tobacco smoke was as productive of precancerous growths in laboratory animals as was fresh tobacco smoke. This finding especially relates to employees and patrons of restaurants, bars, and casinos—the three chief kinds of public smoking sites in the U.S.

It is likely that sidestream smoke will continue to be an important issue in the U.S. even if Ameri-cans who purposely smoke lessen considerably in this decade. Thus there remains the question: Is the tobacco industry willing to try in earnest to develop a cigarette with minimal adverse health effects? In response to consumer demands, cigarette companies in the 1970s and 1980s developed and marketed cigarettes that were filter-tipped and/or low in tar and nicotine. But it turned out that the health risk from smoking such cigarettes was not smaller than that from smoking other tobacco cigarettes. Also in this period, cigarette companies explored both the prospect of making cigarettes with traditionally genetically modified tobacco and the potential of curing tobacco so as to alter its character.

Universal cessation of the habit of smoking is an apparently noble goal, but it may not be realizable in this century. At least until it clearly becomes so, it behooves the healthcare community and public health officials—particularly considering both the obvious and the possible health consequences of human exposure to sidestream smoke—should spare no lawful effort to get the cigarette industry to try to develop and market minimally harmful cigarettes. Effective means of such development exist.

ACSH Scientific Advisor Michael A. Dubick, Ph.D., is Senior Research Pharma-cologist at the U.S. Army Institute of Surgical Re-search, in San Antonio, Texas.

Stephanie E. Dubick is with KRDO Television, in Colorado Springs, Colorado