Monday, April 10, 2006

Challenge Issued to Anti-Smoking Groups: Identify Study that Demonstrates 30 Minutes of Secondhand Smoke Causes Heart Attacks or Retract these Claims

Today I am issuing a challenge to the large number of anti-smoking groups which have made fallacious claims about the acute cardiovascular effects of secondhand smoke: either identify a scientific study which documents that 30 minutes of exposure to secondhand smoke causes heart attacks in healthy nonsmokers or retract these fallacious claims.

According to the widespread propaganda being spread by the anti-smoking movement, 30 minutes of secondhand smoke exposure causes hardening of the arteries, clogged coronary arteries, reduced coronary blood flow, catastrophic or fatal cardiac arrhythmias, heart damage, reduced ability of the heart to pump, heart attacks, and death in nonsmokers, even in those who don't have severe existing coronary disease.

These claims are presently being made by a large number of national anti-smoking groups, including Action on Smoking and Health, Americans for Nonsmokers' Rights, and the Campaign for Tobacco-Free Kids, and by a large number of state and local groups as well, including SmokeFreeOhio, TobaccoScam, and many other state and local anti-tobacco coalitions.

Given the profound implications of such scientific claims for the public safety, I think it is only appropriate that these groups be asked to provide at least one scientific study that documents their claims. I am therefore challenging these anti-smoking groups to provide even a single study that documents that among healthy nonsmokers (without pre-existing severe coronary artery disease), 30 minutes of secondhand smoke causes any of the following:
  • hardening of the arteries ;
  • clogged coronary arteries;
  • reduced basal coronary blood flow;
  • catastrophic or fatal cardiac arrhythmias;
  • heart damage;
  • reduced ability of the heart to pump;
  • heart attacks; or
  • death.
The Rest of the Story

I can tell you now that no anti-smoking group will be able to win this challenge.

The reason is quite simple: there is simply no scientific evidence that 30 minutes of secondhand smoke exposure causes any of the serious health effects listed above.

In fact, it is completely implausible (actually, impossible) for a 30 minute exposure to secondhand smoke to cause most of the above effects. Hardening of the arteries, for example, is a process that takes years (probably a minimum of 20 years). It simply cannot happen in 30 minutes. So there can't be any scientific evidence that 30 minutes of secondhand smoke exposure causes hardening of the arteries, even though a large number of anti-smoking groups are making precisely such a claim.

If it were possible, then one would see very young individuals suffering heart attacks. But the truth is that it is extremely rare to see anyone under age 40 suffer a heart attack simply because they smoked. Since many people start smoking in their teens, this means that it takes a minimum of 20-30 years, not 20-30 minutes, for tobacco smoke exposure to cause atherosclerosis (hardening of the arteries).

If the anti-smoking groups changed the word "minutes" to "years," then I think they might be able to provide scientific studies to support their assertions. But this means that they are off by a factor of about 525,600, or half a million. That's five orders of magnitude.

To call these claims exaggerations is therefore an injustice to the word "exaggerate." They are not merely exaggerations - they are completely fallacious.

I think the tobacco control movement should have a little more scientific integrity then to present scientific information that is off by a factor of half a million. I think we should be able to do a little better than that. And more importantly, we should care about doing a little better than that.

What am I supposed to tell the media when they question me about my opinions about whether the scientific claims of anti-smoking groups can be trusted: "Yes, absolutely...well, kind of...they are definitely within five orders of magnitude."

And how are we to retain any credibility on any scientific issue - including the issue of the chronic health effects of secondhand smoke - when we are off by a factor of half a million on the acute effects of secondhand smoke?

I'll shortly be calling for a retraction of these public claims, but first, let's see if any of the groups making them can provide documentation to back them up. Good luck to all the groups!

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