Tuesday, April 11, 2006

16 More Anti-Smoking and Health Groups Found to Be Disseminating Fallacious Claims About Acute Cardiovascular Risks of Secondhand Smoke

Sixteen more anti-smoking and health groups appear to be disseminating inaccurate information about the acute cardiovascular health effects of secondhand smoke. This revelation comes on the heels of my earlier report that 28 anti-smoking groups were making these completely fallacious claims.

The Claims

Kendall County Health Department: "After only 30 minutes of SHS exposure, your coronary arteries show the same damage as a smoker."

Texas Department of State Health Services: "Just 30 minutes'’ exposure to secondhand smoke can constrict arteries and damage the body'’s ability to supply blood to the heart."

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."

Smoke Free Hampshire & Isle of Wight: "Most importantly, just 30 minutes of breathing secondhand smoke affects blood and blood vessels nearly as much as being a pack a day smoker."

Smokefree Wyoming: "Within 30 minutes, your blood becomes stickier, damaging artery linings and restricting flow."

Oregon Department of Human Services: "Experts have found that just 30 minutes of secondhand smoke exposure can impair blood flow to and from the heart in non-smokers."

American Lung Association of Metropolitan Chicago: "People who spend just 30 minutes in a smoke-filled room have a measurable decrease in oxygen delivered to their heart."

New Jersey GASP: "Secondhand smoke hurts people in as little as 30 minutes. Healthy nonsmokers who enter a smoke-filled room show almost immediate changes in their blood, changes that can result in heart disease and stroke."

Hong Kong Medical Association: "Just 30 minutes exposure is enough to reduce coronary blood flow."

Northern Kentucky ACTION: "30 minutes of exposure is enough to increase your risk of heart attack and stroke."

Share Air: "Just 30 minutes' exposure to secondhand smoke can constrict arteries and damage the body's ability to supply blood to the heart."

Smokefree Anchorage Coalition: Secondhand smoke "increases risk of heart attack after just 30 minutes of exposure."

New York City Coalition for a Smoke Free City: "Just 30 minutes of exposure to secondhand smoke greatly increases non-smokers'’ risk of heart disease."

Illinois Coalition Against Tobacco: "Even as little as 30 minutes of exposure to secondhand smoke has a negative effect on arteries and oxygen's flow to the heart is decreased."

Health 24: "Only 30 minutes of exposure to second-hand smoke can damage a non-smoker's heart and increases the risk of heart disease by 30%."

The Rest of the Story

These claims are inaccurate because what the scientific evidence shows is that acute exposure to secondhand smoke can cause endothelial dysfunction - an early step in the atherosclerotic process - and platelet stickiness in healthy nonsmokers. That's it. There's no evidence that a single 30 minute exposure can actually cause atherosclerosis or clogged arteries - and therefore a heart attack - in an otherwise healthy nonsmoker.

In fact, it's completely implausible (and medically impossible) for 30 minutes of exposure to cause atherosclerosis, since it takes many years for this process to occur. And the platelet aggregating effects of a brief secondhand smoke exposure do not present any risk of precipitating a blood clot and causing a heart attack in someone who does not have severe existing coronary artery disease.

It's not even accurate to claim that a 30 minute exposure to secondhand smoke reduces the blood flow to the heart, because what the Otsuka study actually showed is that there was no reduction in coronary blood flow. In other words, 30 minutes of secondhand smoke exposure was documented not to reduce blood flow to the heart.

The truth is that the Otsuka study, which is being used to back up these claims that 30 minutes of exposure reduces blood flow to the heart, actually provides documentation that this brief exposure does not reduce coronary blood flow and therefore poses no acute risk of clogged coronary arteries and an acute myocardial infarction (heart attack).

Some of the claims being made are so fallacious that they completely defy medical science. For example, the claim that "only 30 minutes of exposure to second-hand smoke can damage a non-smoker's heart and increases the risk of heart disease by 30%" is false on its face. You don't need to review the scientific evidence to appreciate the fact that if you spend 30 minutes in a smoky room, you are not going to have a 30% increased risk of developing heart disease. You are not going to have the same risk of developing heart disease as someone who is exposed to secondhand smoke for many years.

Another particularly fallacious set of claims (although it seems to me that a claim is either fallacious or it's not but I don't know what else to call them) is the assertion that 30 minutes of secondhand smoke decreases oxygen delivery to the heart. I have no idea where that came from. I'm not even aware that the Otsuka study measured oxygen delivery to the heart muscle (it did not). So how can a group make such a claim? You practically have to be making it up.

The rest of the story is that the inaccurate and completely fallacious scientific claims being made by anti-smoking groups are so widespread and so blatantly false that they seriously threaten the credibility of the entire tobacco control movement.

Yet instead of responding swiftly and definitely to resolve the problem and end the crisis, anti-smoking groups and many advocates appear instead to be attacking the messenger. This is no time for ad hominem attacks. This is a time to act decisively in an attempt to preserve the credibility of the movement.

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