ASH (UK) Becomes First Anti-Smoking Group to Publicly Acknowledge that Other Groups are Making False Statements to the Public About Secondhand Smoke

In a letter to the editor of New Scientist magazine, Action on Smoking and Health (UK) became the first anti-smoking group to publicly acknowledge that a number of tobacco control organizations have made false statements to the public about the acute cardiovascular effects of secondhand smoke.

The letter responds to the article in last week's issue which highlighted my concerns about misleading and inaccurate statements being made by nearly 100 anti-smoking groups about the cardiovascular effects of brief secondhand smoke exposure.

In the letter, ASH (UK) writes: "ASH (UK) endorses your conclusion that bad science can never be justified. ASH, unlike some organisations, has never asserted that a single 30-minute exposure to second-hand smoke is enough to trigger a heart attack, and we are not aware of any UK health advocates who have done so. What we do say, based on a growing body of evidence, is that repeated exposure to second-hand smoke can damage coronary arteries, which in turn can trigger heart disease. As a matter of course, we aim to ensure that our work is evidence-based and we would never deliberately distort science to justify a particular campaign. The evidence of the harm to non-smokers exposed to tobacco smoke is so robust that there is no need to exaggerate it to justify tobacco control measures."

ASH (UK) is not to be confused with ASH (US), which in contrast to its British counterpart, has claimed not only that a 30-minute exposure to tobacco smoke can trigger a heart attack, but that such an exposure increases the risk of a fatal heart attack to the same level as that of an active smoker.

The Rest of the Story

ASH (UK) is to be congratulated for its courage and its willingness to publicly condemn the use of inaccurate health claims to support an agenda which it supports. ASH (UK) makes it very clear that in its opinion, the ends do not justify the means. In fact, it argues that the use of bad science can never be justified. I praise ASH (UK) for taking such a principled stand.

In breaking from all of its counterparts in the tobacco control movement by acknowledging that some of its fellow groups are making false statements, ASH (UK) has taken a courageous action. As I know too well, groups or advocates within tobacco control who make any statement of criticism of other groups -- even if justified -- are subject to vicious attack and ostracism from the movement. This is why it is laudable that ASH (UK) was willing to take this principled stand, and to do so in a visible (public) way. In fact, ASH (UK) apparently initiated this response, since it is a letter to the editor. No one forced ASH (UK) to speak out. They did so, apparently, because they felt the issue was important enough.

It is reassuring to me that after two years of challenging these ridiculous statements, one anti-smoking group has finally come out publicly and agreed that I am correct. Yes - some groups have asserted that "a single 30-minute exposure to second-hand smoke is enough to trigger a heart attack." And yes - such a claim, if unqualified by noting that it refers only to people with very severe coronary artery stenosis, is simply wrong. It is bad science. It is unjustified.

ASH (UK) accurately communicates the results of the actual science when it explains to the public that "repeated exposure to secondhand smoke can damage coronary arteries, which in turn can trigger heart disease."

Now that ASH (UK) has spoken out, I hope that other groups will follow suit. However, I don't predict that any U.S. groups will display the integrity shown by ASH (UK).

Incidentally, although the letter may be technically correct in stating that no UK health groups have claimed that a brief exposure to secondhand smoke can cause a heart attack, a number of such groups have made very misleading health claims -- suggesting, for example, that 30 minutes of secondhand smoke causes reduced blood flow to the heart or that it causes clot formation, either of which could be easily (and correctly) construed as potentially triggering a heart attack:

British Medical Association: "Just 30 minutes in a smoky room can reduce the flow of blood to the heart."

British Medical Association, Tobacco Control Resource Centre: "Just 30 minutes in a smoky room can reduce the flow of blood to the heart."

Smoke Free Liverpool: "Just 30 minutes exposure to other people’s tobacco smoke can be enough to reduce blood flow through the heart."

Royal College of General Practitioners: "Just 30 minutes exposure is enough to reduce coronary blood flow in a non-smoker."

Scottish Executive: "Short-term exposure to tobacco smoke also has a measurable effect on the heart of non-smokers: just 30 minutes' exposure is enough to reduce coronary blood flow."

British Heart Foundation: "Furthermore, exposure to cigarette smoke does not have to be particularly prolonged for it to damage your heart. One study has shown that just 30 minutes exposure is enough to reduce coronary blood flow to the heart."

Smoke Free North East: "Just 30 minutes exposure is enough to reduce coronary blood flow."

Smokefree England: "Just 30 minutes exposure is enough to reduce coronary blood flow."

British Heart Foundation: "Just 30 minutes exposure to tobacco smoke can affect the cells lining the coronary arteries and this can contribute to the development of atheroma narrowing the coronary arteries and reducing blood flow to the heart."

Action on Smoking and Health (London): "Short term exposure to tobacco smoke also has a measurable effect on the heart in non-smokers. Just 30 minutes exposure is enough to reduce coronary blood flow."

Clearing the Air Scotland: "30 minutes exposure to second hand smoke is sufficient to reduce coronary blood flow in otherwise healthy adults."

Smokefree Islington (UK): "A study published in the Journal Of The American Medical Association found that just 30 minutes' exposure is enough to reduce coronary blood flow."

Smoke-free Bristol (UK): "Short-term exposure to second-hand smoke has a measurable effect on the heart in non-smokers -– 30 minutes exposure is enough to reduce blood flow to the heart muscle."

Smoke Free North West: "Short term exposure to tobacco smoke also has a measurable effect on the heart in non-smokers. Just 30 minutes exposure is enough to reduce coronary blood flow."

East Cambridgeshire and Fenland PCT: "Being exposed to 30 minutes cigarette smoke can significantly reduce the coronary blood flow in a fit healthy adult."

Smokefree England: "Just 30 minutes exposure is enough to reduce coronary blood flow."

Smoke Free Solihull: "Just 30 minutes exposure is enough to reduce coronary blood flow."

Bradford City Teaching Primary Care Trust: "Within 30 minutes of exposure, platelets thicken, triggering clot formation."

Leeds, Grenville, and Lanark Health Unit: "within 30 minutes, blood platelets are activated, which makes the blood 'stickier' and damages artery linings which can lead to a heart attack."

County Durham and Darlington National Health Service (UK): "Within 20 minutes, passive smoking activates platelets causing them to stick together forming blood clots."

Oldham Primary Care Trust (UK): "Just 30 minutes in a smoky room can thicken the blood and reduce the oxygen needed for red-blooded passion."

Stating that 30 minutes of secondhand smoke exposure reduces blood flow to the heart is incorrect, because the very study which is being used to support such a claim demonstrated that coronary blood flow was not reduced. What was decreased was the coronary flow velocity reserve. I have explained in detail why coronary blood flow and coronary flow velocity reserve are very different things and how by conflating the two, a large number of anti-smoking groups are deceiving the public.

Stating that 20 minutes of secondhand smoke exposure causes blood clots is also inaccurate. On a cellular level, brief tobacco smoke exposure does increase platelet activation, but it is not going to trigger actual clot formation unless a person already has severe, pre-existing coronary artery disease. A healthy person is not going to get a blood clot due to 20 minutes in a smoky environment.

Also worth noting is that the Leeds, Grenville, and Lanark Health Unit does appear to claim that a single 30-minute exposure to secondhand smoke can trigger a heart attack, and they do not qualify this claim by clarifying that it refers only to those with severe existing coronary artery stenosis: "within 30 minutes, blood platelets are activated, which makes the blood 'stickier' and damages artery linings which can lead to a heart attack."

In addition, ASH (UK) does appear to have made the statement that 30 minutes of secondhand smoke is enough to reduce coronary blood flow, which I believe is misleading for the reasons noted above. However, to their great credit, it appears that they have retracted this claim, or at least removed this web page.

Finally, I would just love to know how the Oldham Primary Care Trust determined that 30 minutes in a smoky room reduces the oxygen needed for red-blooded passion. That sounds like a fun study to conduct, or better yet - in which to be a subject.