While I have previously explained how a large number of anti-smoking groups are widely disseminating false claims about the acute cardiovascular health effects of secondhand smoke, there is now evidence that these claims are not only being used to promote smoking bans, but that they have been presented at city council hearings to try to persuade policy makers and that this false information has resulted in misleading policy makers about the science behind secondhand smoke and its effects.
Here, I will relate two examples of false scientific claims being made by anti-smoking groups to policy makers.
The First Story
According to the minutes of a March 24, 2005 meeting of the Children's Health and Environment Committee of the Indianapolis City Council, which was conducting a public hearing of a proposed workplace smoking ordinance, the American Heart Association (Indianapolis Metropolitan Region) testified that:
"Twenty minutes of exposure to secondhand smoke is equal to smoking one pack of cigarettes and results in sticky blood platelets which again increases the chance for heart attack. Thirty minutes of exposure has the same effect on the coronary arteries as a regular smoker, which affects the ability of the artery to open or dilate during times when a person needs more or less blood supply to the heart muscle. Two hours of exposure to secondhand smoke can cause irregular heartbeats, which can lead to an arrhythmia or a heart attack."
The questioning of the American Heart Association speaker revealed considerable confusion about the claim being made:
"Councillor Bradford asked how long it takes to smoke a cigarette. He asked if it only takes 10 minutes to smoke one cigarette, how can 20 minutes of exposure to secondhand smoke be like smoking a pack of cigarettes? Ms. Rench said that the 20 minutes of exposure to secondhand smoke relates to the equivalent effect of a pack-a-day smoker. Councillor Bradford asked if this secondhand exposure refers to one smoker in the room or more than one smoker. Ms. Rench said that she does not have exact statistics on the number of smokers. Councillor Bradford said that if it only takes 10 minutes to smoke a cigarette, does it not make sense that 20 minutes of exposure to secondhand smoke would be more like smoking two cigarettes. Ms. Rench said that the effects on a first-hand active smoker are different from those produced by secondhand smoke. Councillor Talley said that he smoked briefly in the Marine Corps and could smoke a cigarette in a minute and a half, so this time correlation may not be accurate. Ms. Rench said that this comparison is simply saying that if you are a nonsmoker who is exposed to 20 minutes of secondhand smoke every day, it is comparable to the health effects on a pack-a-day smoker. Councillor Keller said that spending 20 minutes in an establishment with heavy smoke, such as a bar, would be the equivalent effects as a person smoking 20 cigarettes throughout the day."
The Rest of the First Story
It is terribly misleading, I believe, to suggest that "Twenty minutes of exposure to secondhand smoke is equal to smoking one pack of cigarettes." If this were true, then people who experienced regular but transient exposures to secondhand smoke would suffer the same health consequences as pack-a-day active smokers. We know that this is not the case. For one thing, lung cancer risk is overwhelming higher in an active smoker than a transiently exposed nonsmoker. For another thing, chronic obstructive lung disease (such as emphysema) is a serious risk among an active smoker, but does not occur among passive smokers. So I simply don't see how one can suggest to policy makers that twenty minutes of secondhand smoke exposure is equal to actively smoking one pack of cigarettes.
It is also quite misleading, I believe, to suggest that 30 minutes of secondhand smoke exposure "results in sticky blood platelets which again increases the chance for heart attack." Sure, 30 minutes of exposure does increase platelet stickiness, but there is no evidence that this is of any clinical significance for nonsmokers. Perhaps for someone with severe existing coronary artery disease this could be a possible danger, but it is certainly not accurate to suggest that as a general matter, 30 minutes of exposure increases the chance for a heart attack.
It is also quite misleading, I believe, to suggest that "Thirty minutes of exposure has the same effect on the coronary arteries as a regular smoker, which affects the ability of the artery to open or dilate during times when a person needs more or less blood supply to the heart muscle." Thirty minutes of exposure clearly doesn't have the same effect on the coronary arteries as being a regular smoker. For starters, the effect of 30 minutes of exposure is transient and reversible and for all intents and purposes, clinically meaningless for most nonsmokers. In a healthy nonsmoker, there is no evidence that the temporary endothelial dysfunction caused by transient secondhand smoke exposure has any clinically meaningful effect on coronary artery blood flow. In fact, there is documentation that baseline coronary artery blood flow is not affected and in that there is little if any effect even for someone running on a treadmill. But active smoking can cause narrowing of the coronary arteries leading to myocardial infarction and death. I don't see how these two disparate levels of health effects are in any way comparable.
Perhaps the most misleading statement of all is the claim that "Two hours of exposure to secondhand smoke can cause irregular heartbeats, which can lead to an arrhythmia or a heart attack." Actually, calling this misleading is being quite generous. It's actually a false statement in my view. Two hours of exposure does not cause irregular heartbeats and it certainly does not lead to a serious arrhythmia or heart attack. What it does is decrease heart rate variability, which is simply a measure of cardiac autonomic function. There could be consequences, perhaps, for a person with severe coronary artery disease, but for most nonsmokers, a single two-hour exposure poses no known risk of an arrhythmia or heart attack.
But the story here is not just that the testimony was highly misleading and in some cases inaccurate (and therefore I would say somewhat irresponsible). The story is also that the council was clearly misled by the testimony. When questioned about the obviously false statement that 30 minutes of exposure to secondhand smoke is equal to the effects of actively smoking one pack of cigarettes a day, the American Heart Association spokesperson apparently started grasping at straws and revealed that she actually didn't understand what she was talking about. Quite clearly, she was just repeating dogma that she had seen or heard but didn't really have any depth of scientific understanding of what she was talking about.
The Second Story
According to the minutes of the June 12, 2003 meeting of the Laredo (Texas) City Council on a proposed smoking ban, the city health director apparently provided testimony in which he claimed that:
"Thirty minutes of breathing secondhand smoke compromises the ability of the blood to manage LDL 'bad' cholesterol by depressing anti-oxidant defenses - the effect persists for several hours after exposure ends. The arteries' ability to dilate is also reduced, diminishing the flow of blood to the heart. After 120 minutes of breathing secondhand smoke, the risk of an irregular heartbeat (arrhythmia) that can itself be fatal or trigger a heart attack increases."
The Rest of the Second Story
I find it inaccurate to claim that 30 minutes of exposure to secondhand smoke diminishes "the flow of blood to the heart." Sure, it does reduce coronary flow reserve velocity, but this is of no consequence in an otherwise healthy person, and it does not translate into diminished blood flow to the heart. In fact, the study from which these data are derived demonstrated that there was no change in coronary blood flow after 30 minutes of secondhand smoke exposure.
I also find it inaccurate to claim that "After 120 minutes of breathing secondhand smoke, the risk of an irregular heartbeat (arrhythmia) that can itself be fatal or trigger a heart attack increases." There is no evidence that such an exposure has any effect on the risk of a catastrophic or fatal cardiac arrhythmia.
What these examples demonstrate (and I'm sure there are many more) is that the fallacious claims being made by anti-smoking groups to support smoking bans are not simply innocent mistakes that are of no significant consequence. In fact, these claims are being used inappropriately to advance public policies and it appears that they are significantly misleading or deceiving public policy makers about the acute health effects of secondhand smoke.
I've stated clearly many times that I support workplace smoking bans and so I am not writing because I want to try to derail efforts to promote these policies. I am writing because as much as I support these policies, I do not believe it is right to use fallacious claims to support the policies, and I think it is unfortunate that policy makers are being misled in the name of promoting the public's health.