John Luik

February 2008

All in the family

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A quarrel erupts in the anti-tobacco movement about scientific accuracy and telling the truth.

John Luik

Of all the “truths” that make up the sacred text of the anti-tobacco movement, none is more central than that which asserts that exposing nonsmokers to even the smallest amounts of tobacco smoke threatens their lives. First emerging from several flawed studies in the 1980s, then given official status in the U.S. Environmental Protection Agency’s 1992 report, and reasserted in even more expansive form in the most recent U.S. surgeon general’s report on secondhand smoke (2006), the claim that environmental tobacco smoke (ETS) is a significant health risk to nonsmokers is perhaps the single most important driver of tobacco control policy in the past 25 years, since it has so dramatically and comprehensively changed the nature of where and when smokers can smoke.

The anti-tobacco movement, however, has not been satisfied with these claims about ETS that have had at least some connection, however tenuous, to science. Instead, they have continually pressed to make the “truth” about the risks of ETS more dramatic, more attention getting and more frightening. While part of this is attributable to the movement’s generally low regard for science and accuracy about tobacco risks, it is also driven by the fact that exaggerating the dangers of ETS is the most consistently successful way to push for not only smoke-free public places but private spaces as well. Simple, uncompromising and above all frightening messages about the risks of ETS appear to move even the most skeptical, reluctant and considered of policy makers.

Consider a couple of examples of this new line of “truth” about the risks of ETS. Several studies have argued that comprehensive public smoking bans have been followed by almost immediate, dramatic and unprecedented declines in heart attack admissions to hospital emergency rooms. Even more dramatically, many anti-tobacco groups have claimed that a single exposure of just 30 minutes to secondhand smoke can increase a nonsmoker’s risk of having a fatal heart attack to that of a regular smoker. As we don’t have space to look at both of these claims, I will concentrate on the 30-minute peril.



The 30-minute peril

It’s difficult to trace the 30-minute claim to its original source, in part because it is now regularly made by dozens, if not hundreds, of anti-tobacco groups worldwide in some form. Michael Siegel, in his blog, The Rest of the Story: Tobacco News Analysis and Commentary, says that the claim derives from the U.S. anti-smoking group Americans for Nonsmokers’ Rights (ANR) (See Siegel, Dec. 12, 2007), which is a major source of information for activists arguing for public smoking bans. But the same claim is also made by the Action on Smoking and Health (ASH), a Washington, D.C.-based anti-tobacco group. In a Jan. 27, 2006, press release that advocated comprehensive public smoking bans, including on outdoor smoking, ASH claimed that “the Centers for Disease Control has warned that breathing drifting tobacco smoke for as little as 30 minutes … can raise a nonsmoker’s risk of suffering a fatal heart attack to that of a smoker.”

The British Heart Foundation makes a somewhat more guarded claim by noting that a 30-minute ETS exposure can affect the cells lining the coronary arteries and reduce blood flow to the heart, though the clear implication is that a brief ETS exposure increases one’s risk for a heart attack. At least 15 other U.K. anti-tobacco groups make similar comments about the effect of brief ETS exposure in reducing coronary blood flow.

Nor is it simply anti-tobacco groups who are making this claim. The New York City Department of Health, perhaps best known for its ban on trans fat and its attempt to force restaurants to post the calorie count of their foods, published an ad in the New York Times in 2002 claiming that “Just 30 minutes of exposure to secondhand smoke can greatly increase your risk of heart attack.”

Equally responsible for spreading the 30-minute peril story, however, is the U.S. surgeon general, whose 2006 press release accompanying his ETS report, together with his comments to the press about ETS, contained several claims about the cardiac risks of even brief exposure to ETS. For instance, the surgeon general’s press release claimed that “even brief exposure to secondhand smoke has immediate adverse effects on the cardiovascular system and increases risk for heart disease…” Again, in his remarks at the press conference releasing the ETS report, the surgeon general noted, “Brief exposure can have immediate harmful effects on blood and blood vessels, potentially increasing the risk of a heart attack.”



No basis Just what then are we to make of such claims about the cardiac risks of healthy nonsmokers exposed to ETS for short periods of time? To begin with there is no scientific evidence that a 30-minute exposure of a healthy nonsmoker—that is someone without severe heart disease—to ETS causes a heart attack. Indeed, the claim is nonsensical to anyone who knows anything about the underlying mechanisms of heart disease. Heart attacks, or myocardial infarctions to speak technically, are generally the product of atherosclerosis—a disease in which arterial blood vessels become—and here is the key word—progressively blocked. But atherosclerosis doesn’t occur in 30 minutes.

Second, the research that supposedly supports the 30-minute heart attack risk says no such thing. The study by Otsuka et al. “Acute effects of passive smoking on the coronary circulation in healthy young adults” (JAMA, 2001) exposed healthy nonsmokers—that is, nonsmokers with no history of heart disease—to ETS for 30 minutes and then analyzed the effect on endothelial function (the thin layer of cells lining the coronary arteries) by measuring the coronary flow velocity reserve. They found that in nonsmokers the reduction in endothelial function, after ETS exposure, was equivalent to that found in regular smokers.

But this reduction in endothelial function does not mean that the nonsmokers were in imminent danger of suffering a heart attack after their 30-minute ETS exposure, as implied by the anti-tobacco lobby. Over time, tobacco smoke could lead to atherosclerosis and a heart attack, but not as a result of one 30-minute exposure. Indeed, as the authors note, the exposure to secondhand smoke had “no effect on basal coronary flow velocity”—it did not reduce blood flow to the heart, damage the circulatory system or the heart itself.

The very article supposedly backing the risk of a heart attack following 30 minutes of ETS exposure actually refutes that claim. While the study shows that ETS exposure might affect the cells lining the coronary arteries, it also shows that it does not produce any damage to the heart or create an immediate risk for a heart attack.

Third, the epidemiological evidence supporting any connection between long-term ETS exposure and heart disease is exceptionally weak. Of the 42 studies that have looked at ETS exposure (spousal, occupational and social) and heart disease, only 18 show a statistically significant association. Even more curious is the fact that while the relative risk for heart disease in smokers is 1.7—a weak association—that of nonsmokers exposed to ETS is supposedly 1.3, even though their exposure is 1/500th of a smoker’s, a finding that cannot be explained on any understanding of a dose-response relationship.



The end justifies the means

If this were the end of the story we could simply put this untruth down to more of the anti-tobacco lobby’s usual tactics of misrepresenting science in order to scare citizens, politicians and regulators into supporting draconian tobacco control policies. But this story has a decidedly different twist, which owes much to the efforts of Michael Siegel and his tobacco policy blog, The Rest of the Story.

Siegel, who is an anti-tobacco activist at the Boston University School of Public Health and the author of a flawed study on ETS exposure among restaurant employees (Siegel “Involuntary smoking in the restaurant workplace: a review of employee exposure and health effects” JAMA 1993), has used his blog to take aim repeatedly at a variety of activist claims that he considers to be scientifically inaccurate. And at the center of his focus has been the claim about a heart attack risk for nonsmokers after 30 minutes of ETS exposure.

As he writes in his blog for Dec. 12, 2007: “It is not true that 30 minutes of secondhand smoke exposure causes ANY heart damage, much less damage that is similar to that sustained after many years of active smoking. It is also not true that the hearts of nonsmokers exposed to secondhand smoke for 30 minutes are impaired in their ability to get life-giving blood.”

Siegel’s criticisms of the antis’ claims about the risk of a heart attack from a 30-minute ETS exposure have recently attracted considerable attention with an article and editorial in the New Scientist in November criticizing the anti-tobacco movement’s willingness to distort the “facts in order to make their case” about ETS, and also an article in the Wall Street Journal’s “Informed Reader” section.

In response to these criticisms, ASH’s executive director, John Banzhaf, asserted that the claim was taken from the CDC. But this is not true since the CDC references the Otsuka study, which does not make this claim. Stanton Glantz, an anti from the University of California in San Francisco, rationalizes the misrepresentation by saying that “when you take the science and put it in the public domain you can’t include all the caveats. The messages have to be simplified so people can understand them.”

This, of course, is part of the old health promotion line first championed by former Canadian health minister Marc Lalonde, who argued that the public was essentially too stupid to understand the science behind lifestyle issues like drinking, smoking and dieting, so the “truth” necessary to get them to change their ways had to be presented without any troubling uncertainties. What it really says is that lying about the science is fine as long as it is for a good cause like creating a world without smoking and smokers.

As Siegel noted in reply to Glantz “Are you kidding me? ... Should we also tell the public that drinking three beers causes cirrhosis of the liver, liver cancer, hepatitis, and potentially, death? ... Should public health practitioners therefore be putting out messages in which we remove all the ‘caveats’ and state that drinking three beers puts you at the same risk of death as being a chronic, lifelong alcoholic?”

Then too, the question is not one of a caveat or a quibble as Glantz suggests. Rather it is whether the claim about a 30-minute ETS exposure causing heart attacks is true. As we have seen, it is not. Interestingly, neither Glantz nor Banzhaf have responded to Siegel’s challenge to provide the scientific evidence to support the claim about the 30-minute heart attack peril from ETS.

As a result of these attacks on the scientific accuracy of the anti’s ETS claims, Siegel has been, in his own words, “personally attacked, publicly condemned, accused of being a traitor, accused of being funded by tobacco companies, called a fanatic” and effectively expelled from the anti-tobacco movement. (See his “Is the tobacco control movement misrepresenting the acute cardiovascular health effects of secondhand smoke exposure?” in Epidemiologic Perspectives and Innovations, Oct. 10, 2007, for a fuller account of his troubles with the anti-tobacco movement.)

Reflecting on the results of his questioning of anti-tobacco scientific “truths,” Siegel writes that “in the past year or so, I believe that there has been a marked change in the movement. There seems to be much less of a concern for scientific accuracy, and for the first time that I am aware, I believe that scientific integrity is being sacrificed for the sake of promoting our agenda.” And again, “I have come to the impression that the tobacco control movement does not allow room for any difference of opinion, and that those who dissent with any aspect of the prevailing wisdom must be discredited, attacked and silenced.”



Deliberate distortion

What’s curious, at least in one sense, is that it has taken a dedicated activist like Siegel so long to realize what the anti-tobacco movement is really like and really stands for. Sadly, its departure from scientific accuracy is not only a product of the “past year,” but rather of at least the last 20 years. Ever since it moved beyond talking about the risks of smoking and started making claims about youth smoking, advertising, addiction, nicotine manipulation, secondhand smoke and taxation, its commitment has been less to truth-telling than to fanatical advocacy. Increasingly its central interest is not so much supporting sensible policies to reduce or prevent smoking but furthering its anti-industry objectives through quite literally any means. And as its science has become ever less reliable, its tolerance for dissent, as Siegel has learned, has evaporated. If good public policy generated through vigorous debate and founded on reliable science were ever hallmarks of the anti-tobacco movement, they most certainly are not now.

As Siegel observes, “The ends do not justify the means …. These are values which cannot and should not be trodden upon by public health organizations simply to promote a favored policy.” Indeed. About the only bright spot in this all-too-depressing tale of scientific misrepresentation is how widely it has been reported, how clumsy has been the response of Glantz and Banzhaf, and how embarrassing it has been for the anti-tobacco movement. Still, one can muster a bit of sympathy for former “true” believers like Mike Siegel, who should get the last word.

“I never received a membership card when I joined the anti-smoking movement, but if I had, today is the day I’d be sending it back. These are not the ethical standards with which I would like to be associated.”

We can’t improve on that.