According to the U.S. Surgeon General, merely brief exposure to secondhand smoke can cause cardiovascular disease and inhaling even a tiny amount of tobacco smoke can cause cancer.
In conjunction with the release of the new Surgeon General's report on smoking, the Office of the Surgeon General issued a press release summarizing the findings of the report.
According to the press release:
1. "Even brief exposure to secondhand smoke can cause cardiovascular disease and could trigger acute cardiac events, such as heart attack."
2. "Inhaling even the smallest amount of tobacco smoke can also damage your DNA, which can lead to cancer."
Based on the Surgeon General's statements, walking past a smoker on the street could cause a person to develop cardiovascular disease and cancer.
The press release accompanies the 2010 Surgeon General's report on smoking, entitled "How Tobacco Smoke Causes Disease: The Biology and Behavioral Basis for Smoking-Attributable Disease." This report reviews the biological mechanisms by which smoking causes a wide range of adverse health effects.
The Rest of the Story
Fortunately, it is simply not true that even brief exposure to secondhand smoke can cause cardiovascular disease. Luckily, it takes many years of exposure before the process of atherosclerosis (hardening of the arteries) can occur. If brief tobacco smoke exposure could cause heart disease, we would sadly see many young people in their twenties and thirties walking around with cardiovascular disease, and many dying from it at those ages. Even active smoking does not generally lead to heart disease unless you smoke for many years. Thus, it is simply untrue to assert that brief exposure to secondhand smoke can cause cardiovascular disease.
This is the second time that the Office of the Surgeon General has misrepresented and distorted the science of the acute cardiovascular health effects of secondhand smoke. The Surgeon General's press release which accompanied the 2006 report on secondhand smoke made the same false assertion.
The press release's assertion flies in the face of common medical sense. How could it possibly be that a brief exposure to secondhand smoke can cause heart disease? It takes many years for heart disease to develop. It takes years of exposure to tobacco smoke even for a smoker to develop heart disease. I estimate that it takes at least 25 years of exposure (based on the fact that very few smokers are diagnosed with heart disease before age 40).
So how could it possibly be that for an active smoker, heart disease takes 25 years of exposure to tobacco smoke to develop, but for a passive smoker, it only takes a brief exposure?
While the press release may be correct in suggesting that a brief exposure to tobacco smoke could cause a heart attack (although only in someone with pre-existing heart disease), it is completely false in claiming that a brief exposure can cause cardiovascular disease.
Fortunately as well, inhaling the smallest amount of tobacco smoke does not lead to cancer. While the press release is correct in asserting that the tiniest amount of tobacco smoke can damage your DNA, it simply is not true that someone who inhales the tiniest amount of tobacco smoke may well develop cancer because of it. There is certainly no evidence to support such a statement.
Moreover, there is nothing in the Surgeon General's report itself which concludes that, or supports the assertions that a brief exposure to secondhand smoke can cause cardiovascular disease or cancer. These assertions basically come out of nowhere. They have been manufactured to create a sense of public hysteria, but they are unsupported by any science whatsoever.
I don't see why there is a need to lie to the public about the very real and serious hazards of cigarette smoking and secondhand smoke exposure. Why is the truth not enough?
In addition, there are a number of reasons why I'm not so sure that the publicity focus on the absence of any safe level of exposure to smoking or secondhand smoke is entirely appropriate and effective as a public health message.
First, the message is not particularly meaningful. One can say that there is no safe level of exposure to any carcinogen. There is no safe level of exposure to car exhaust. There is no safe level of exposure to the sun's rays. There is no safe level of exposure to X-rays. There is no safe level of exposure to the benzene that is found in some sodas. There is no safe level of exposure to radon in homes. There is no safe level of exposure to arsenic that is found in many people's drinking water.
For that matter, there is no safe speed at which you can drive a car without risk of injury or death. There is no risk-free way to have sex with someone who has HIV infection. There is no safe method to travel from one place to another.
So stating that no amount of smoking or secondhand smoke is safe is not particularly meaningful. It also didn't take a detailed report to draw such a conclusion. We knew that already. It follows logically from the fact that tobacco smoke contains carcinogens. In fact, we have known that no amount of tobacco smoke is safe since at least 1961, when a Philip Morris internal report detailed the many carcinogens and toxins in tobacco smoke.
Second, this emphasis on the hazards of minute levels of, and brief exposures to, tobacco smoke seems to belie the importance that the public must place on assessing the dose of tobacco smoke in making decisions about their potential health risk. Dose consists both of the concentration of the smoke and the duration of exposure, and both of these are important considerations that we want the public to be aware of. Don't we?
Maybe I'm wrong, but isn't it more useful and informative to provide the public with a sense of the relative levels of exposure to tobacco smoke in different environments and situations then to scare the public into simply thinking that any exposure is terrible and that (perhaps) all exposures are equally bad? I think that it is important for the public to have some appreciation of the strong and important relationship between dose and risk. And I'm afraid that the overwhelming emphasis on there being no risk-free level of tobacco smoke exposure may obscure the importance of the dose-risk relationship.
Failing to emphasize the dose-risk relationship could have negative public health consequences, both from an individual and a policy perspective. From an individual perspective, is it not possible that some people will conclude that since any secondhand smoke exposure is putting them at risk, it doesn't make sense to reduce their exposure if they cannot eliminate it. In other words, for people who cannot avoid some exposure to secondhand smoke, is there any incentive for them to reduce their exposure if they are repeatedly hammered over the head with the idea that their limited smoke exposure is going to kill them anyway?
And for smokers, what incentive is there for them to cut down on their smoking if it is true that even brief exposure to secondhand smoke may cause them to have a heart attack anyway? If you're going to have a heart attack one way or another, why not continue to smoke and at least enjoy yourself before you keel over?
Furthermore, what incentive is there for a smoker to quit if he truly believes that a single cigarette is enough to cause cancer. The smoker who has already smoked thousands of cigarettes, each of which could give her lung cancer, is not exactly going to feel some sense of urgency, given that she is apparently just a cancer victim waiting to happen.
The point is that by making tobacco smoke exposure sound so bad, such that even a tiny and brief exposure is hazardous and such that if you are exposed you are doomed to disease, aren't we taking away an incentive for people who cannot eliminate their exposure entirely to reduce it? Are we not taking away an incentive for smokers to quit smoking if they know that they will still hang out in the same smoky bars and be exposed to secondhand smoke. What's the point of their quitting smoking if the secondhand smoke in these bars is going to kill them anyway and there is no perceived benefit of reducing the level of their exposure? What is the point of their quitting if any one of the cigarettes they have already smoked may kill them anyway?
Frankly, I think the people who are going to be hurt by this report are smokers. While for the most part, nonsmokers will be scared by this news and will largely become more vigilant and more aggressive in their attempts to avoid the smoke, many smokers may be alienated by the suggestion that even a few whiffs of tobacco smoke could kill them. There doesn't seem to be any point in quitting smoking by that logic.
This kind of reminds me of the mistake that public health advocates made in telling gay men in San Francisco that the only way to prevent AIDS was to use a condom every time. For some men, that is not a reasonable or possible dictate. It's not going to happen. But if that man believes that even one time without a condom is going to cause him to get AIDS, what incentive is there for him to make efforts to increase the frequency of condom use, especially when that one time has already occurred?
From a public policy perspective, I'm afraid that the publicity surrounding the Surgeon General's report is basically going to be a green light to expand efforts to ban smoking outdoors in places where people can easily avoid exposure and that it may actually take the focus off of indoor workplaces with extremely high levels of secondhand smoke exposure, such as casinos and bars. And I think it may result in more of a focus on protecting people with transient, periodic exposure to secondhand smoke and further neglect of people who are exposed regularly.
Third, by emphasizing that any brief exposure to tobacco smoke can cause lung cancer, I believe this publicity may well harm efforts to search for the other causes of lung cancer. By giving people the impression that any nonsmoker who gets lung cancer may well have gotten it from a single secondhand smoke exposure, even if their exposure was brief, are we not doing a potential disservice to the search for other causes of non-smoking-related lung cancer?
Fourth, when you give a message like this one - everyone is at risk - do you not undermine efforts to try to reach people who really are at the most risk? By scaring everyone in the population into thinking that they are at risk of disease from tobacco smoke, are we not taking attention away, perhaps, from the groups that are at the highest risk because of the highest levels of exposure? And might not these groups be less likely to take action to protect themselves than if the message was that certain groups are at particularly high risk and need to be protected urgently?
In some ways, this approach is really a cop out. Instead of having the acumen to examine risk levels and set priorities in policy making and intervention, you are basically just throwing up your hands and saying: "Everyone is at risk. Everyone needs to avoid secondhand smoke. Everyone needs to just not smoke a single cigarette. Everyone - just don't do it!"
Rather than being a call for specific and prioritized actions to prevent disease in the most effective and efficient manner possible, it seems that the publicity put out by the Surgeon General's office is more of just a general public scare, devoid of any priorities, focus, or policy or intervention directives. It appears more like a vague warning of "Fire," rather then a clear directive like "Fire at 12 Main Street. Evacuate 12 Main Street, and then 8 and 10 Main Street." You don't want to go on television to tell people that there is a fire at 12 Main Street and everyone is potentially at risk. You want to first evacuate those buildings. We need to have some sense of direction and priorities in public health, and they should be based on a rational assessment of levels of risk. And that means that you have to evaluate and consider dose.
The rest of the story is that the Office of the Surgeon General somehow finds it necessary to lie to the American people in order to convince us of the hazards of smoking. Apparently, we are too stupid to understand that smoking is a bad thing if the truth is that smoking for many years causes disease. Apparently, we think that unless a single cigarette can kill us, it is a problem that is not worth worrying about.
As I have shown, the opposite is probably closer to the truth. If we are accurately informed about the dose-risk relationship, we are more likely to make rational decisions. If all we hear is the hysteria - that a single, tiny exposure to tobacco smoke can cause heart disease and cancer - we are more likely to ignore the entire message. We've all experienced such an exposure already, so we're all doomed, I guess. So what incentive is there to quit smoking or avoid secondhand smoke at this point?
There are enough serious health effects of smoking and secondhand smoke that are real. Why the need to make up alarmist claims that are not true? In the long run, these claims are going to do more harm than good. They are going to undermine the credibility of our public health officials and weaken the public's trust of public health as an institution.
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