By Robert B. Sklaroff, William T. Godshall
Posted: Monday, October 1, 2001

ARTICLES
Publication Date: October 1, 2001

Environmental tobacco smoke (ETS) causes adverse health effects in nonsmokers. But the severity of those effects has been the source of considerable debate. Also known as sidestream, secondhand, or passive smoking, efforts to reduce exposure to ETS have become politicized, as the tobacco industry [TI] uses misdirection to distract policy makers from implementing reasonable measures to protect the public health.

This essay will summarize the fundamental knowledge of ETS and demonstrate how it can be applied responsibly.

Secondhand Smoke Risks

ETS is a complex mixture of many chemicals resulting from the combustion of tobacco, including systemic toxicants, such as hydrogen cyanide and sulfur dioxide; muta-gens and carcinogens, such as benzo[a]pyrene and formaldehyde; the reproductive toxicants nicotine, cadmium, and carbon monoxide; and airborne particulates.

The National Institutes of Health's National Toxicology Program's 9th issue of the Report on Carcinogens listed ETS as a "known" human carcinogen, and ETS is also classified as a Group A carcinogen ("known to cause cancer in humans") under the carcinogenic assessment guidelines published by the United States Environmental Protection Agency (EPA).

Concentrations of respirable particulates have been measured inside smoky rooms at levels (up to 1,370 ug/m3) that greatly exceed the EPA outdoor air standard of 50 ug/m3, while concentrations of sulfur dioxide, nitrogen dioxide, and carbon monoxide inside smoky rooms also often exceed EPA outdoor air standards. The highest concentrations of respirable particulates and other chemicals in ETS have been measured in smoky cars, bars, restaurants, and bingo halls.

According to the 1997 California Environmental Protection Agency (Cal/EPA) report "Health Effects of Exposure to Environmental Tobacco Smoke," regular exposure of children to ETS poses relative risks of 3.5 for sudden infant death syndrome (SIDS), 1.75-2.25 for inducing asthma, 1.6-2 for exacerbating asthma, 1.62 for middle ear infection, and 1.5-2 for lower respiratory disease. A relative risk of 1.6 means that an exposed person has a 60 percent greater risk of contracting the disease, compared to a non-exposed individual. Therefore, youth, especially infants and young children, are at significant risk of disease due to ETS exposure.

Just as disease risks increase with the dose and duration of exposure to toxins, carcinogens, and mutagens, studies have consistently found that they increase with greater ETS exposure (e.g., spouses of smokers and workers in smoky bars and restaurants).

A study recently published in The Journal of the American Medical Association, however, found that just a half-hour of exposure to ETS reduced the blood flow in nonsmoking men by impairing the function of endothelial cells in their hearts and blood vessels. This study supports other evidence linking ETS to heart disease.

The Tobacco Institute recognized that ETS posed risks to the industry itself since as early as 1978, when they commissioned a Roper Organization report that concluded:

What the smoker does to himself may be his business, but what the smoker does to the non-smoker is quite a different matter. . . . This we see as the most dangerous development yet to the viability of the tobacco industry. . . . The strategic and long-run antidote to the passive smoking issue is, as we see it, developing and widely publicizing clear-cut, credible, medical evidence that passive smoking is not harmful to the non-smoker's health.

Smoke-free Policy Solutions

As with most public health problems, efforts to reduce public ETS exposure have become widespread as the scientific research process has yielded a better understanding of the links between ETS and disease. In addition to education, lawsuits and legislation have been major catalysts for restricting indoor smoking. Commercial and residential property leases are increasingly including "no smoking" clauses.

Progress is being made. Recently published studies found that, in 1999, nearly 70 percent of indoor workers reported totally smoke-free policies in their workplace, and nearly 60 percent of middle and high school children reported smoke-free polices in their home. In contrast, only four percent of workplaces in America were smoke-free in 1986 when U.S. Surgeon General C. Everett Koop released "The Health Consequences of Involuntary Smoking."

In 1999, the U.S. Census Bureau interviewed 270,000 private-sector workers regarding exposure to ETS at indoor workplaces. 68.6 percent of the workers nationwide have smoke-free policies. The five highest-ranked states were Utah (83.9%), Maryland (81.2%), California (76.9%), Massachusetts (76.8%) and Vermont (76.6%). The five lowest-ranked states were Nevada (48.7%), Kentucky (55.9%), Indiana (58.1%), South Dakota (59.7%), and Michigan (60.7%). Although Utah's ranking may be attributed to its large Mormon population (with its nonsmoking culture), all of the top-five ranked states have enacted extensive legislative protections from workplace exposure to ETS.

The 1999 Legacy Media Tracking Survey of more than 15,000 students nationwide in grades 6-12 found that 59.9 percent of students reported living in a smoke-free home, including 77.1 percent of households without a smoker and 32.0 percent of households with a smoker. Statewide surveys by the California Health Department found that 52.9 percent of children in the state living in households with a smoker reported having smoke-free homes in 1999, an increase from 36.9 percent in 1994. As expected, parents are the vast majority of smokers who live in households with children.

The National Report on Hu- man Exposure to Environmental Chemicals, released earlier this year by the U.S. Centers for Diseases Control and Prevention, measured serum cotinine levels of nonsmokers. Cotinine is a metabolite of nicotine that tracks exposure to ETS among nonsmokers. The report revealed a 75 percent decrease in the median serum cotinine level (from 0.20 ng/mL to 0.05 ng/mL) of nonsmokers in a survey of blood samples taken in 12 locations across the country in 1999, as compared to blood samples taken in 1988 and 1991.

This report also revealed, however, that people under the age of 20 had higher median serum cotinine levels than adults, and that more than half of American youth are still exposed to ETS. Although ten percent of the adults had serum cotinine levels greater than 0.38 ng/mL, 10 percent of the youth had levels greater than 1.13 ng/mL, nearly a threefold difference.

As smoke-free policies have expanded dramatically during the past fifteen years, nonsmokers who are chronically exposed to the greatest levels of ETS include children and spouses of smokers, blue-collar workers, and service workers. Achieving further reductions in ETS exposure remains a formidable challenge for public health advocates, who continue to confront cultural entrenchment and a well-financed and powerful TI.

The TI has heavily funded numerous campaigns and front groups to challenge and deny the health risks of ETS over the past 20 years. They oppose smoke-free legislation at the local, state, and federal levels. The TI has routinely funded economic impact studies that incorrectly predicted huge financial losses for businesses and entire metropolitan areas if indoor smoking was restricted. In 1988, after the TI recognized that rapidly spreading local ordinances were the primary driving force for the growing number of smoke-free policies in workplaces and public places, it shifted its legislative strategy to lobby for weak statewide laws that preempted the enactment and enforcement of stronger local ordinances.

Over the past decade, the TI has essentially conceded smoke-free policies in most workplaces, and has focused its efforts on preserving public smoking in bars, restaurants, casinos, hotels, bowling alleys, and other entities in the hospitality industry. Philip Morris, the nation's largest tobacco company, has spent hundreds of millions of dollars developing and promoting its "Accommodation Program" and "PM Options," which try to convince hospitality businesses and trade associations that smoke-free policies decrease business revenues and are unpopular with customers.

To deal with tobacco smoke pollution, these and other TI programs have encouraged businesses to install expensive ventilation systems instead of implementing smoke-free policies. And, while air conditioning manufacturers avoid making explicit health protection claims (because many pollutants and chemicals in secondhand smoke are not removed by their ventilation systems), the tobacco and ventilation industries have established a mutually beneficial partnership to discourage smoke-free policies.

Numerous studies in different municipalities and states have consistently found that smoke-free laws have not reduced overall restaurant or bar revenues, and that a majority of people support these laws. Thus, it appears that only the tobacco and ventilation industries have financially benefited from the continued exposure of people to secondhand smoke within hospitality venues.

As previously mentioned, children are not only at greater risk of disease from ETS exposure, but children also are exposed to more ETS than are nonsmoking adults. To address this, in 1994 Congress enacted the Safe Kids Act, which banned smoking in all federally funded child daycare centers and K-12 schools nationwide. Meanwhile, California and a growing number of local governments have recently enacted laws prohibiting smoking at outdoor children's playgrounds.

But while the protection of children has been an effective argument for reducing many other environmental health and safety risks, this has not been the case with secondhand smoke. The vast majority of youth exposure is the result of their own parents' smoking in their homes and cars. Not only are children less empowered than adults to request smoke-free policies, most health organizations and government officials who have successfully advocated and enacted smoke-free laws for workplaces and public places have been reluctant to call for mandatory smoking restrictions in homes and cars.

But restrictions on parental smoking are not without precedent. Courts in at least a dozen states, usually involving child custody cases, have prohibited or restricted smoking by a parent in their own home in order to protect a child with severe respiratory problems. And bills have been introduced, though not enacted, in Pennsylvania and Colorado to ban smoking in cars if a child is present. But nearly all other efforts to reduce children's secondhand smoke exposure in homes and cars have relied upon education and voluntary encouragement, and have had limited success.

A key strategy for solving many public health problems has been to target interventions to populations at greatest risk. But while a growing percentage of Americans now live and work in smoke-free environments, many of those at the greatest risk of harm from secondhand smoke (i.e., children and hospitality industry workers) are still exposed on a daily basis. Future efforts to reduce secondhand smoke exposure should focus primarily on these populations.

(From Priorities, Vol. 13, No. 4)