Monday, October 23, 2006

Action on Smoking and Health Promoting Street and Sidewalk Smoking Bans and Completely Misrepresenting the Science

NOTE: In recognition of the challenge I have issued to anti-smoking groups to correct their misleading claims (a letter has been sent to a large number of these groups), I am re-publishing my first post about the misleading claims that anti-smoking groups are making about the acute cardiovascular health effects of secondhand smoke, which appeared on January 30, 2006. Here it is:

In a press release issued Saturday, Action on Smoking and Health (ASH) became the first anti-smoking organization to officially promote the adoption of laws broadly banning smoking outdoors, including on streets and sidewalks. ASH backed up its support for these smoking bans by offering to assist local governments in defending the legality of these laws.

According to the press release: "The formal designation of secondhand tobacco smoke as a 'toxic air contaminant' opens the door to many additional restrictions on smoking, both in cars where children are present and even on public sidewalks... One city has already asked its staff to submit a report on the legality and feasibility of prohibiting smoking on city streets and sidewalks -- the legality of which has already been upheld in a law suit in which ASH's Executive Director ... participated. The designation follows on the heels of findings that even small amounts of tobacco smoke outdoors can be dangerous. ... ASH also says it will help to defend the legality of bans on smoking on streets, sidewalks, and in other public places as it did successfully in the past."

To support its recommendation that smoking be banned on streets and sidewalks, ASH presented scientific data on the health hazards associated with brief exposure to secondhand smoke, stating that: "Even for people without such respiratory conditions, breathing drifting tobacco smoke for even brief periods can be deadly. For example, the Centers for Disease Controls [CDC] has warned that breathing drifting tobacco smoke for as little as 30 minutes (less than the time one might be exposed outdoors on a beach, sitting on a park bench, listening to a concert in a park, etc.) can raise a nonsmoker'’s risk of suffering a fatal heart attack to that of a smoker. The danger is even greater for those who are already at an elevated risk for coronary problems: e.g., men over 40 and postmenopausal women, anyone who is obese, has diabetes, a personal or family history of heart or circulatory conditions, gets insufficient exercise, has high blood pressure, cholesterol, etc."

ASH also stated that: "A 2004 study by the Centers for Disease Control and Prevention found that as little as 30 minutes of exposure to drifting secondhand smoke can have a serious or even lethal health impact by rapidly increasing the tendency of blood to clot."

Finally, ASH stated: "In cases where drifting tobacco smoke was present and a nonsmoker suffered a heart attack, asthmatic attack, or other similar problems, the municipality which owns and operates the beach, park, playground, etc. could be liable since it was on notice of the known health dangers but failed to take the 'reasonable' step of banning smoking as taken by many other outdoor areas."

The Rest of the Story

I am quite serious when I suggest that this action by ASH, if unchecked by the rest of the tobacco control community (and especially if supported by other anti-smoking groups), is going to cause the whole smoke-free movement to implode, resulting not only in no bans on smoking on sidewalks and streets, but in a severe dent in what I see as legitimate efforts to regulate smoking indoors, in workplaces.

There is, in my opinion, simply no justification for invoking the state's police powers to regulate smoking on streets and sidewalks, places where people are free to move about and where, in most situations, people can simply avoid substantial exposure to secondhand smoke. And I am aware of no scientific evidence that secondhand smoke exposure on streets and sidewalks is a significant public health problem.

And I think the public is going to view smoke-free advocates as complete fanatics because of this type of action that ASH is taking.

Nevertheless, the saddest part of the story is not ASH's promotion of banning smoking on streets and sidewalks. Instead, the saddest part of the story is the completely misleading, inaccurate, and irresponsible public representation of the science which ASH alleges supports the need to ban smoking on streets and sidewalks.

It is simply not the case 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, and in my view, it is not the case that CDC made such a claim.

The truth is that an otherwise healthy nonsmoker cannot suffer a heart attack as a result of 30 minutes of exposure to secondhand smoke. A nonsmoker's risk of a heart attack from breathing tobacco smoke for 30 minutes is not the same as that of a smoker. It is actually ZERO.

You are not going to have a heart attack if you don't have coronary artery disease; and 30 minutes of exposure to secondhand smoke is not going to clog your coronary arteries.

I cannot over-emphasize the fact that ASH's claim is completely fallacious. It's not like ASH is distorting the truth here. In my opinion, they are just completely making this up, or at least, misinterpreting the data so badly that it has the appearance of coming out of nowhere. You simply aren't going to get atherosclerosis and clogged coronary arteries in 30 minutes!!!

It is not just inaccurate and misleading to make a public statement like this. It is also, in my opinion, irresponsible. This could scare nonsmokers into thinking that they are going to keel over and drop dead from a heart attack if they walk down a street and breathe in secondhand smoke for 30 minutes.

And I think it is also irresponsible to try to intimidate city officials by suggesting to them that if they don't ban smoking in a beach, park, or playground, they are putting nonsmokers at risk of dropping dead of a heart attack. There is simply no evidence that acute exposure to secondhand smoke can cause a heart attack in a healthy nonsmoker, and it is completely implausible that any such evidence could exist in the first place. You can't develop coronary artery disease in 30 minutes.

What the CDC did say, and what the relevant research does say, is that 30 minutes of exposure to secondhand smoke can cause endothelial dysfunction, as measured by coronary flow velocity reserve (CFVR), in nonsmokers to the same degree as seen in smokers (see Otsuka R, Watanabe H, Hirata K, et al. Acute effects of passive smoking on the coronary circulation in healthy young adults. JAMA 2001; 286:436-441 and Pechacek TF, Babb S. How acute and reversible are the cardiovascular risks of secondhand smoke. BMJ 2004; 328:980-983).

But endothelial dysfunction is a far cry from a heart attack!!!

In fact, what endothelial dysfunction measures is the early process of atherosclerosis. As the authors (Otsuka et al.) concluded: "The present findings suggest that reduction of CFVR after passive smoking may be caused by endothelial dysfunction of the coronary circulation, an early process of atherosclerosis, and that this change may be one reason why passive smoking is a risk factor for cardiac disease morbidity and mortality in nonsmokers."

What this means is that acute exposure to secondhand smoke can result in endothelial dysfunction in nonsmokers that if prolonged and repeated over a long time, could eventually result in atherosclerosis and heart disease.

In other words, this study provides a potential mechanism for the observed increase in heart disease risk among passive smokers. It provides biologic plausibility for a causal relationship between exposure to secondhand smoke and heart disease. But it does not suggest that an otherwise healthy nonsmoker could suffer a heart attack as a result of a 30 minute exposure to secondhand smoke, and it certainly does not mean that a nonsmoker's risk of a heart attack approaches that of a smoker's after 30 minutes of exposure to secondhand smoke.

The only possible acute risk of secondhand smoke exposure in terms of heart attack risk is the slight possibility that in people with existing severe coronary artery disease, the endothelial dysfunction triggered by acute exposure to secondhand smoke might be enough to trigger a coronary event (i.e., a heart attack). There is very little evidence that this is the case, but it is possible, and I wouldn't argue with recommending that nonsmokers with coronary artery disease should try to minimize or eliminate their exposure to secondhand smoke.

It is also worth noting that one piece of evidence ASH relied upon to support its contention that small amounts of acute exposure to secondhand smoke causes heart attacks is what Jacob Sullum aptly called "The Vanishing Miracle of Helena and Pueblo."

The fact that heart attack admissions fluctuated downwards in these two small cities in association with a smoking ban was apparently enough for ASH to conclude not only that the downward fluctuation was due to the smoking ban, but that the observed effect was due to a reduction in secondhand smoke exposure (even though it is completely implausible that the observed reductions could be due to reduced secondhand smoke exposure even if they were due to the smoking ban in the first place and even though there is no evidence that a reduction in secondhand smoke exposure explains the decline [smoking status was not measured in either study]).

The rest of the story is two-fold:

First, the rest of the story is that the anti-smoking movement is now on record as supporting and promoting a wide ban on smoking in non-enclosed outdoor areas where people can move about freely, including on public streets and sidewalks. Unless this is contested by other anti-smoking groups, I believe it is a big step towards making ourselves perceived by the public as a bunch of fanatics.

And I believe it is a big step towards what I fear will be the eventual implosion of the smoke-free movement. After all, public opinion is critical to enable even legitimate legislation, and if we risk losing that, we risk losing everything. That is why I am bringing this to the tobacco control community's attention and speaking out against it.

Second, the rest of the story is that the misuse and misrepresentation of science by anti-smoking groups has risen to a new and unprecedented level. An anti-smoking group has claimed that 30 minutes of secondhand smoke exposure raises a nonsmoker's risk of a heart attack to the level of a smoker. This is not just a stretch of the science, it is completely fallacious and it seems to come out of nowhere.

I'm not claiming that it is an intentional fabrication. Perhaps it is just a very errant interpretation of the scientific evidence. But either way, the bottom line is that it is a public misrepresentation of the scientific evidence that is misleading, inaccurate, and irresponsible.

This is the lowest I have observed the anti-smoking movement sinking in terms of misleading the public, because there is simply no basis whatsoever for the claim that a nonsmoker's risk of a heart attack after 30 minutes of secondhand smoke exposure is the same as that of a smoker's. In fact, after 30 minutes of secondhand smoke exposure, an otherwise healthy nonsmoker's risk of a heart attack is basically ZERO. Now you can see why I don't view this as merely a gross over-estimate (like the Helena and Pueblo claims, where at least there is some plausibility to the idea that a smoking ban could reduce heart attacks to some small degree), but as a "fact" that has the appearance of coming out of nowhere.

It should go without saying that I think ASH needs to publicly retract or correct this communication and apologize for misleading the public so severely.

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