Banning Smoking in Public Places: Title and subTitle BreakTime to Clear the Air

During the past 3 decades, definitive evidence has accumulated that secondhand smoke causes serious disease and shortens life span. The recent surgeon general's report on involuntary exposure to tobacco smoke concluded that secondhand smoke causes lung cancer, coronary heart disease, and premature death.¹ Legislation that eliminates public smoking will therefore reduce the burden of chronic disease and premature mortality. The workplace, which is a major source of secondhand smoke exposure, is a particularly important target for preventive strategies.

Recent reports indicate that there are also more immediate respiratory health benefits from mandating smoke-free workplaces. In 1998, our research group² reported that California legislation banning smoking in bars and taverns led to substantially reduced secondhand smoke exposure among bartenders. In parallel with reduced exposure, the prevalence of sensory irritation symptoms (eye, nose, and throat irritation) and respiratory symptoms (cough, wheeze, and shortness of breath) declined markedly. Pulmonary function also improved after reduction of secondhand smoke exposure. The main conclusion was that smoke-free workplace legislation improved the respiratory health of bartenders over a short time period.

In 2004, Ireland became the first country to pass a national workplace smoking ban. Scotland, Norway, Sweden, and Italy now also have laws prohibiting smoking in the workplace. At present, 11 US states, 9 Canadian provinces, 5 European nations, New Zealand, regions of Australia, and other locations around the world prohibit smoking in the workplace. These smoke-free workplace laws have provided a “laboratory” for studying how such legislation affects public health.

In this issue of JAMA, Menzies and colleagues³ report the effects of a national smoking ban on bar workers in Scotland. Using a design similar to the earlier study,² these investigators documented markedly reduced secondhand smoke exposure after the smoking ban, based on both self-reported exposure and serum cotinine, a biomarker of secondhand smoke exposure. After the smoke-free legislation went into effect, bar workers experienced sustained reduction of sensory irritation symptoms and respiratory symptoms as well as improved pulmonary function.

The report by Menzies et al confirms and amplifies previous research demonstrating reduced secondhand smoke exposure and decreased respiratory symptoms among restaurant and bar workers after smoke-free workplace mandates were enacted in the United States,^{2 ,4} Ireland,^{5 - 7} Norway,⁸ and New Zealand.⁹ In addition, one study suggests that workplace smoking bans are associated with reduced incidence of acute myocardial infarction.¹⁰ Taken together, there is compelling scientific evidence that smoke-free workplace legislation is rapidly effective in improving the health of workers.

An emerging body of evidence also indicates that secondhand smoke exposure is a likely cause of exacerbations of adult asthma.^{11 - 16} Menzies et al³ provide valuable new information about this potentially vulnerable subgroup. After the smoking ban went into effect, bar workers with asthma experienced an even larger improvement in pulmonary function than those without asthma. Moreover, individuals with asthma had evidence of reduced airway inflammation (exhaled nitric oxide) and improved asthma-specific quality of life. Consequently, it appears that the benefits of smoke-free workplace legislation are even greater for persons with chronic airway disease.

In the United States, progress has been made toward reducing secondhand smoke exposure but it remains widely prevalent. Between 1988 and 2002, serum cotinine concentrations declined by approximately 70% among nonsmoking US residents aged 4 years or older.¹⁷ The prevalence of any secondhand smoke exposure, based on detectable serum cotinine levels, also declined from 88% to 43%.¹⁷ Although these trends are encouraging, nearly 1 of 2 people living in the United States is still being exposed to secondhand smoke.^{1 ,17} Certain population subgroups, especially children and non-Hispanic blacks, experience even higher levels of exposure.¹⁷ Given the known health risks of passive smoking, secondhand smoke exposure still remains too common.

How can secondhand smoke exposure be reduced further to decrease the serious health risks? After the home, the workplace is the major source of involuntary exposure to tobacco smoke for most adults.^{1 ,18} In some workplaces, employees are exposed to very high levels of secondhand smoke.¹⁹ Bar and tavern workers, in particular, are exposed to high ambient levels of secondhand smoke, up to 4 to 6 times higher than in other workplaces.²⁰ To prevent the adverse health consequences of passive smoking, the workplace remains a high priority for smoke-free legislation.

Three common arguments are advanced against mandating smoke-free bars, restaurants, and other hospitality businesses. Each is fallacious. First, laws to prevent smoking in bars will not be effective. Four years after the California ban on smoking in bars, adherence with the law was high: 99% of bars in restaurants and 76% of freestanding bars were smoke-free.²¹ Near perfect adherence has been reported in Boston,²² Ireland,⁷ and New Zealand.²³ Second, the general public will not accept smoke-free bars and restaurants. In fact, a series of international studies shows that most people do support smoke-free bars and restaurants. Moreover, public opinion becomes increasingly positive following smoke-free legislation.^{9 ,23 - 26} Third, smoke-free laws will cause bars and restaurants to lose money. Using sales tax and other objective financial data, studies now conclusively demonstrate that bars, restaurants, and hotels do not lose revenue after becoming smoke-free.^{27 - 30} In fact, some of these studies actually show a growth in income. In sum, smoke-free legislation is effective, accepted by the public, and has no negative economic impact.

Creation of smoke-free workplaces has another important public health benefit—a higher rate of smoking cessation among active smokers.³¹ Those who continue to smoke reduce their daily cigarette consumption. Shortly after the Irish smoke-free workplace legislation went into effect, a substantial proportion of smokers quit smoking (15%), and many attributed their smoking cessation to implementation of the law.⁷ Smoke-free workplace laws, by reducing passive and active smoking, will lead to substantive health benefits for the population.

Mandating smoke-free workplaces will decrease secondhand smoke exposure and will improve respiratory health,^{2 ,4} prevent chronic disease, and extend life span. Important salutary health effects occur in as little as 1 month after cessation of secondhand smoke exposure. The comprehensive body of research documenting the serious adverse health effects of passive smoking provides a powerful rationale for prohibiting smoking in all public places. The time has come to clear the air.