The California Environmental Protection Agency report on secondhand smoke, which is probably the most comprehensive review of the subject and which drew the controversial (even within the tobacco control community) conclusion that secondhand smoke causes breast cancer, did not even suggest that secondhand smoke causes pulmonary emphysema in nonsmokers.
In fact, the report stated that any effects of secondhand smoke on chronic lung function in nonsmokers are limited to small decrements in lung function, and is mainly in the form of exacerbating symptoms of patients with existing chronic lung disease:
"While lung function effects are less pronounced in adults than in children, ETS exposure appears to play a role in the genesis of chronic lower respiratory tract symptoms in otherwise healthy individuals and produces small, but measurable, decrements in pulmonary function. In adults, exposure to ETS at home and/or work was less associated with the onset of respiratory illness but rather with the aggravation of the symptoms and severity of existing bronchitis, sinusitis and emphysema."
The Surgeon General, in his comprehensive report on secondhand smoke, also fails to conclude that secondhand smoke is a cause of emphysema. He mentions that there is suggestive evidence, but it is not adequate enough to support a causal conclusion at this time:
"The evidence is suggestive but not sufficient to infer a causal relationship between secondhand smoke exposure and risk for chronic obstructive pulmonary disease."
Yesterday, I highlighted a number of shoddy scientific claims being communicated to the public by SmokeFreeOhio, including the conclusion that secondhand smoke causes emphysema. To my surprise, it now turns out that a large number of anti-smoking groups are implicated in prematurely communicating to the public that secondhand smoke causes emphysema, including such prominent groups as the Campaign for Tobacco-Free Kids and the American Cancer Society.
Here is a run-down of groups that are making this claim:
SmokeFreeOhio: "Secondhand smoke can cause the debilitating disease pulmonary emphysema, causing severe damage to the walls of the air sacs, with the lungs losing their capacity to expand and contract."
Campaign for Tobacco-Free Kids: "In addition to lung cancer, secondhand smoke is proven to cause heart disease, emphysema and other illnesses and is responsible nationally for thousands of deaths each year."
Texas Department of State Health Services: "Secondhand smoke is known to cause lung cancer, emphysema and heart disease. ... Constant exposure to secondhand smoke greatly increases an employee's risk of lung cancer, heart disease and emphysema."
ASH (UK): "Secondhand Smoke Linked to Lung Disease in Young People. As many as one in nine young adults living in industrialized countries are at risk of developing a deadly lung condition known as chronic obstructive pulmonary disease (COPD). Smokers are particularly likely to get the disease. But people who inhale secondhand smoke are at risk too."
MASSPIRG: "Exposure to secondhand smoke causes cancer, emphysema, heart attacks, respiratory illnesses, and stroke in adult nonsmokers. ... Exposure to secondhand smoke causes some of the same serious illnesses as active smoking does: cancer, emphysema, heart attacks and stroke in adult nonsmokers."
American Cancer Society, Campaign for Tobacco-Free Kids, and American Heart Association: "Exposure to secondhand smoke causes cancer, heart disease, emphysema, and other serious diseases."
Center for Media and Democracy: "In 1986, U.S. Surgeon General C. Everett Koop released an analysis concluding that secondhand smoke was a significant health threat to nonsmokers, and a host of other studies by prominent health organizations have reached similar conclusions. The most common and serious effects are asthma, emphysema, and heart disease."
Boston Public Health Commission (cached - not active link): "Exposure to secondhand smoke causes cancer, emphysema, heart disease, respiratory illnesses, and stroke in adult nonsmokers."
Smoke-Free for ME: "Many people suffer chronic and debilitating conditions caused by secondhand smoke-related diseases. These include emphysema, cancer, heart disease, stroke, chronic bronchitis, and asthma."
SmokeFreeOhio: "Secondhand smoke causes cancer, heart disease, stroke, asthma, emphysema, and other serious illnesses."
GASP of Colorado: "Nonsmokers exposed to secondhand smoke risk developing emphysema, lung cancer, chronic bronchitis, breathing difficulties, and heart disease."
Healthy Ohioans: "In adults, SHS is a cause of lung cancer, heart disease, emphysema, asthma attacks, respiratory illnesses, stroke, impotence, and other cancers."
Ohio Department of Health: "Long-term health problems [of secondhand smoke]: Heart disease and stroke; Lung diseases such as emphysema and reduced lung capacity."
Allina Hospitals & Clinics: "Secondhand smoke causes serious health problems, including asthma, bronchitis, emphysema, lung cancer and heart disease."
Campaign for Tobacco-Free Kids: "In addition to these new findings, secondhand smoke is scientifically proven to cause lung cancer, heart disease, emphysema and other illnesses and is responsible nationally for thousands of deaths each year."
Onward Austin: "Secondhand smoke also causes emphysema and lung disease."
The Center for Social Gerontology, Smoke-Free Environments Law Project: "Over the past twenty years, medical science has shown that nonsmokers, when they breathe SHS, suffer many of the same diseases as smokers, including: Heart Disease, Stroke, Lung and other cancers, Respiratory Infections, Emphysema, Asthma."
SmokeFreeSociety: "Those most affected by secondhand smoke in our homes are children, as they are exposed to the hazardous poisons that can hinder the growth of their lungs and put them in danger of severe respiratory diseases. Children are being stricken at early ages by asthma and emphysema."
American Lung Association of Metropolitan Chicago: "Secondhand smoke is a leading cause of preventable death in this country. It causes heart disease, cancer, stroke and emphysema."
Iowa Public Television, Tobacco Prevention Series: "Students learn that secondhand smoke can cause serious diseases such as asthma, bronchitis, emphysema, heart disease, pneumonia and cancer."
Smoke-Free at Work: "There is evidence to show a cause/effect relationship between ETS and emphysema."
American Cancer Society: "Secondhand smoke also causes as many as 40,000 deaths from heart disease every year. Plus, it causes emphysema and lung disease, and also increases the risk that babies will die of Sudden Infant Death Syndrome."
North Carolina Alliance for Health: "secondhand smoke has been proven to cause cancer, heart disease, stroke, emphysema and asthma in both smokers and non-smokers"
Smoke Free Catawba: "There is overwhelming scientific evidence that secondhand smoke is a direct cause of: lung cancer, heart disease, lung and bronchial infections, emphysema, sudden infant death syndrome (SIDS), eye irritation, weakened sense of smell, hearing loss, vision problems, increased headaches, asthma, and ear infection."
Easy Breathing Avon: "The harmful effects of second hand smoke are well known. Secondhand smoke exposure can lead to: Heart Disease, Lung Cancer, and emphysema..."
The Rest of the Story
I guess I don't understand anymore why we in tobacco control need a Surgeon General's report, or any other scientific reviews of medical and epidemiologic science for that matter.
If we are going to communicate to the public that a causal relationship has been proven between secondhand smoke and emphysema without waiting for there to exist sufficient scientific evidence to draw such a conclusion, then what does it matter what the Surgeon General's report, or any other careful scientific review says?
Why don't we just take the slightest bit of evidence about every possible association that secondhand smoke may have and tell the public that secondhand smoke causes that disease?
Frankly, I'm not sure I see any reason for me to continue with my research on the health effects of secondhand smoke. Anti-smoking groups appear to be so anxious to heighten the emotional impact of their messages and frighten the public that they do not need solid science to inform their communications any longer. My role as a producer of the science upon which to base our communications in tobacco control is apparently obsolete.
Shoddy science has taken over, and it has apparently infiltrated all the way up to the top. It's not even clear to me that anyone cares about the scientific integrity of the movement.
The shame of this all is that our credibility is going to take a big hit from all of this. In the name of trying to marginally increase the scare value of our message in the short-term, we are risking the long-term credibility of the movement.
I don't see how that tradeoff makes any sense.
It's not clear to me exactly how this all happens. The language of the claims seems quite similar, so perhaps it just takes one organization to make the claim and then other organizations follow, without carefully checking the validity of the claim before making it themselves.
After 21 years of what I consider to be rigorous scientific research on secondhand smoke and other aspects of tobacco control, it deeply saddens me to see the lack of scientific integrity that now characterizes the anti-smoking movement.