To remind readers of the claim, here it is:
ASH is publicly claiming, in an effort to promote its agenda, that: "Even for people without such respiratory conditions, breathing drifting tobacco smoke for even brief periods can be deadly. For example, the Centers for Disease Controls [CDC] has warned that breathing drifting tobacco smoke for as little as 30 minutes (less than the time one might be exposed outdoors on a beach, sitting on a park bench, listening to a concert in a park, etc.) can raise a nonsmoker'’s risk of suffering a fatal heart attack to that of a smoker."
They actually go further than this and warn cities that there is a good chance that nonsmokers may keel over from a heart attack if they are exposed to secondhand smoke in wide-open outdoors places like beaches or parks and that these cities can then be held liable for the heart attack deaths of these nonsmokers:
"In cases where drifting tobacco smoke was present and a nonsmoker suffered a heart attack, ... the municipality which owns and operates the beach, park, playground, etc. could be liable since it was on notice of the known health dangers but failed to take the 'reasonable' step of banning smoking as taken by many other outdoor areas."
In today's response, entitled "Summarizing the Deadly Effects of Secondhand Smoke," ASH lists four major points about the deadly effects of secondhand smoke. The first 3 of these points I have no problem with.
But the fourth point states that "even for some people without such respiratory conditions, breathing drifting tobacco smoke for even brief periods can be deadly. For example, the Centers for Disease Controls [CDC] has warned that breathing drifting tobacco smoke for as little as 30 minutes (less than the time one might be exposed outdoors on a beach, sitting on a park bench, listening to a concert in a park, etc.) can raise a nonsmoker'’s risk of suffering a fatal heart attack to that of a smoker." [emphasis is mine].
ASH goes on to defend its claim by:
- citing the published CDC article, which does itself seem to make a claim that it is possible that a brief exposure to secondhand smoke could cause a heart attack in a nonsmoker;
- citing a published scientific article which stated that: "The effects of even brief (minutes to hours) passive smoking are often nearly as large (averaging 80% to 90%) as chronic active smoking;” and
- citing 2 newspaper articles.
The Rest of the Story
In many ways, this action by ASH is even more troubling to me than its initial promulgation of the fallacious claim.
After all, I am the first to admit that one can make mistakes, that one can unintentionally misstate scientific information, that one may not always be careful enough in reviewing scientific claims, and that when one is writing a long document, one may not take the time to verify and confirm every claim that is made.
Had ASH simply apologized for the misleading claim and corrected it, I would have had no problem, the point would have been clarified and fixed, and the story would be over. We could all simply move on.
Unfortunately, ASH instead chose, apparently, to defend and then restate, reiterate, reinforce and re-emphasize its fallacious claim.
Let's look now at ASH's justification for making this obviously false claim:
1. A CDC article suggested that it is possible that 30 minutes of exposure may cause a heart attack in a nonsmoker.
First of all, stating that it is "possible" is a far cry from stating that 30 minutes of exposure increases the risk of a heart attack. It is possible that eating a Big Mac could precipitate a heart attack in someone, but I wouldn't publicly make a claim that eating Big Macs raise one's risk of a heart attack unless I had a little better documentation than that.
Second of all, CDC never stated that the possibility of a heart attack holds for an otherwise healthy nonsmoker.
Third of all, let's completely give ASH the benefit of the doubt here and let's stipulate, for the sake of argument, that CDC has actually stated: "There is solid scientific evidence to support the conclusion that 30 minutes of secondhand smoke exposure significantly raises the risk of a fatal heart attack in an otherwise healthy nonsmoker."
Let me reiterate that CDC did not draw this conclusion, but let's stipulate that they had.
How do you get from that to the public claim that 30 minutes of secondhand smoke exposure increases the risk of a fatal heart attack in a nonsmoker to that of a smoker? That's a fallacious extrapolation that CDC clearly did not make.
The "evidence" upon which that extrapolation was apparently made was a scientific study showing that 30 minutes of secondhand smoke exposure causes endothelial dysfunction equivalent to that observed in smokers. OK - fine. But you cannot simply replace "endothelial dysfunction" with "fatal heart attack."
As I have attempted to explain (attempt #1; attempt #2), endothelial dysfunction is simply a measure of the early stages of atherosclerosis. What the study means is that 30 minutes of secondhand smoke exposure is enough to initiate some of the early changes seen in the atherosclerotic process. If that exposure were repeated over and over again for many years, it could cause atherosclerosis. Thus, this study provides biologic plausibility for the finding that chronic secondhand smoke exposure causes heart disease. But it in no way implies that 30 minutes of exposure can cause your coronary arteries to go from normal to almost completely clogged. That just can't happen.
As I have also noted, eating a Big Mac or too many tater tots (that is, a high-fat meal) has been shown to cause endothelial dysfunction. But this doesn't mean that an otherwise healthy person could drop dead of a heart attack from eating a Big Mac!
2. A published scientific article which stated that: "The effects of even brief (minutes to hours) passive smoking are often nearly as large (averaging 80% to 90%) as chronic active smoking.
This is accurate. But the rest of the story is that the "effects" that this article is talking about is not a "fatal heart attack," but instead, endothelial dysfunction, platelet aggregation, and other cellular and biochemical changes. You can't take this finding and turn it into a claim that brief passive smoking causes fatal heart attacks.
3. Some newspaper articles.
I would hope that we would be relying on something more definitive and reliable than newspaper articles to support our scientific claims as public health organizations.
While ASH is apparently trying to defend itself by claiming that it is merely reiterating what CDC reported, I find that defense to fail. Mainly because CDC never made a claim that 30 minutes of secondhand smoke exposure increases the risk of a fatal heart attack among otherwise healthy nonsmokers to that of a smoker.
Now before I close, let me make one thing perfectly clear. I am not suggesting that in any way, ASH is lying or being dishonest. I'm not saying that they don't believe that what they are saying is true. I'm not saying that they are intentionally trying to distort the scientific data. I understand that they seem to have made an errant interpretation of some scientific data. That's fine. It's not dishonest. It's just errant. Perhaps they are simply reporting what they read in the newspaper. That's not dishonest in any way, it's just irresponsible when it comes to reporting scientific conclusions that one could independently confirm and evaluate without relying on the newspaper to interpret the data for you - especially when the scientific claim in question is so obviously ridiculous.
I'm not suggesting that every single piece of information in a newspaper needs to be fact-checked. I readily admit that I don't do that. But I think you need to have some minimum standards by which you at least fact-check, verify, and critically evaluate and analyze information that is so obviously ridiculous, implausible, and unbelievable.
Regardless of the reason, the end result is that ASH is making a fallacious scientific claim. And I'm simply stating my opinion that this is not an advisable practice for public health and tobacco control groups. At very least, it is misleading to the public, who might actually go away thinking that even if they don't have existing heart disease, if they walk down a street and breathe in secondhand smoke for 30 minutes, they are at substantial risk of dropping dead from a heart attack. I think it's irresponsible of a public health organization to be spreading such misinformation. And I think that ultimately, it might harm the scientific credibility and reputation of anti-smoking organizations.
Finally, I could let the whole thing go as just a simple mistake that could be quickly and easily forgotten if ASH had simply clarified, qualified, or corrected its statement. We all make mistakes. Readers of my blog will know that I myself have made some mistakes in reporting - some serious ones - and in that situation I attempted to immediately correct the error, clarify the facts, and apologize.
But instead, ASH has compounded the problem by defending its fallacious claim and in fact, reiterating it and re-emphasizing it to the public.
No comments:
Post a Comment