Tuesday, October 19, 2010

ANR Removes Unsupported Thirdhand Smoke Claim from Web Site

Presumably in response to my commentaries pointing out the lack of scientific support for the claim that touching a smoker's clothing can cause massive skin and neurological injury to children, Americans for Nonsmokers' Rights (ANR) has removed from its web site all references to this claim, which was originally made by Action on Smoking and Health (ASH) and based on a gross exaggeration of a press release by a textile institution (original ANR web page; current ANR web page).

I congratulate ANR on having the scientific integrity to remove this unsupported claim from its web site. I hope that ASH will also follow suit.

As I explained yesterday, the rigor of our scientific review of claims that we make is critical because if we make exaggerated claims in one area (e.g., thirdhand smoke), it will affect the public's perception of our credibility in making claims in another area (e.g., secondhand smoke or even active smoking). We don't want the public to throw away the baby with the bath water. But that's exactly what people will do once we lose the public's trust. People are not going to discriminate between the accurate claims and those which are exaggerated or untrue. They will simply discount everything that we say.

We saw an excellent example of this in the swine flu scare last year, when exaggerated claims made by health groups led to massive disregard for the very serious and real - but far less hysterical - risks posed by swine flu. As a result, vaccination rates were dismal for the swine flu vaccine. This led to needless morbidity and even mortality. It was a real life example of how loss of the public's trust due to exaggerated health claims can lead to a public health disaster.

The Rest of the Story

Now that ANR has removed the unsupported claim that merely touching a smoker's clothing can cause massive skin and neurological damage, I hope that it reviews and removes its equally hysterical and unsupported claim that 30 minutes of secondhand smoke exposure causes heart damage similar to that caused by chronic active smokers and that 30 minutes of exposure reduces the ability of the heart to get life-giving blood.

The claim that ANR makes is as follows: "Just thirty minutes of exposure to secondhand smoke can cause heart damage similar to that of habitual smokers. Nonsmokers’ heart arteries showed a reduced ability to dilate, diminishing the ability of the heart to get life-giving blood."

ANR has grossly exaggerated the results of the Otsuka et al. study so much that they turned an important scientific finding into a blatant misrepresentation of the truth.

It is not true that 30 minutes of secondhand smoke exposure causes any heart damage, much less damage that is similar to that sustained after many years of active smoking. It is also not true that the hearts of nonsmokers exposed to secondhand smoke for 30 minutes are impaired in their ability to get life-giving blood.

In fact, the Otsuka et al. study, which is the one being relied upon for this statement, actually demonstrated that there is no impairment of basal coronary artery blood flow in subjects exposed to high levels of secondhand smoke for 30 minutes. The study itself documents that there was not any reduced ability of the heart to get life-giving blood!

Thus, the statement is contradicted by the very study which ANR claims supports it.

There is, in fact, no evidence that 30 minutes of secondhand smoke causes any heart damage. Does it impair the function of the cells lining the coronary arteries? Yes. But does that cause heart damage? No. Not from just 30 minutes of exposure.

If sustained over many years, the endothelial dysfunction caused by tobacco smoke exposure could result in atherosclerosis. However, this is not going to occur from a 30-minute exposure. So it is massively deceptive to suggest that a 30 minute exposure causes heart damage, much less that it causes heart damage that is similar to that observed in long-term active smokers, who may have developed severe coronary artery stenosis and suffered heart attacks which destroyed heart muscle.

Given the real scientific evidence about the hazardous effects of secondhand smoke exposure, including the development of heart disease among individuals with chronic secondhand smoke exposure, why does ANR need to exaggerate and distort the truth?

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