Apparently in response to a number of posts on The Rest of the Story which pointed out the inaccuracy of several secondhand smoke health claims made on the ClearWay Minnesota web site (post 1; post 2; post 3; post 4), the organization has removed the contentious claims from the site. The inaccurate claims appeared in a manual for local advocates working on clean indoor air ordinances.
The two claims in question, along with the reasons why I questioned their accuracy, are as follows:
Claim #1: "Blood flow in the coronary arteries is decreased in healthy young adults exposed to secondhand smoke."
Why It is Misleading: In fact, the study that is being used as the basis for this claim revealed that coronary blood flow in healthy young adults exposed to secondhand smoke was not decreased. What was decreased was the coronary flow velocity reserve, which has no clinical meaning for these young adults in the absence of sustained or repeated exposure. The clear impression of the statement is that a healthy young person exposed to secondhand smoke for 30 minutes will suffer a reduction in coronary artery blood flow. This is untrue.
I think that a normal person reading the claim would have gotten the impression that any exposure to secondhand smoke, even brief exposure, leads to a reduction in coronary blood flow in a healthy young person, such that the individual could be at risk of a heart attack (since most people correctly identify reduced coronary blood flow with heart attacks).
I had expressed the opinion that is it not appropriate to scare healthy young people into thinking that they may suffer a heart attack due to a short-term secondhand smoke exposure.
Claim #2: "Current scientific data suggest that eating in a smoky restaurant can precipitate myocardial infarctions in nonsmokers and increase the risk of fatal and non-fatal cardiac events in nonsmokers by about 30 percent."
Why It is Misleading: There are no scientific data which show that eating in a smoky restaurant can cause a heart attack. But more importantly, it is impossible that eating in a smoky restaurant could increase the risk of cardiac events by 30%, since being exposed to secondhand smoke for a lifetime only increases the risk of cardiac events by about 30%.
These two inaccurate claims appeared in a toolkit that is designed to be used by many local anti-smoking groups to promote smoking bans. Failure to correct these "facts" would have resulted in the widespread dissemination of false health claims by anti-smoking groups.
ClearWay corrected the first claim by changing it to state that coronary "flow reserve" is decreased in healthy young adults exposed to secondhand smoke and that this indicates that "passive smoking can cause endothelial dysfunction in the coronary circulation."
ClearWay corrected the second claim by deleting the assertion that eating in a smoky restaurant increase heart attack risk by 30% and by simply stating that "exposure to secondhand smoke" increases that risk by 30%.
The Rest of the Story
I congratulate ClearWay Minnesota for showing the concern and taking the time to address my concerns and correct these claims in its smoking ban manual. This is an unusual occurrence, as most of the other anti-smoking groups to which I have communicated my concerns have ignored them or indicated that they do not really care.
I wish all the anti-smoking groups which are making misleading or inaccurate claims about the acute cardiovascular health effects of secondhand smoke would follow ClearWay Minnesota's lead and delete or correct them.