New Study on Secondhand Smoke is… | Campaign for Tobacco-Free Kids
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New Study on Secondhand Smoke is Based on Flawed Science and Funded by the Tobacco Industry

Statement of Matthew L. Myers, President Campaign for Tobacco-Free Kids
May 16, 2003

Washington, D.C. — A study being published today that claims to show there is no link between exposure to secondhand tobacco smoke and coronary heart disease and lung cancer is based on flawed science and, not surprisingly, is funded by the tobacco industry. This study's conclusions are contrary to the findings of the World Health Organization's International Agency for Research on Cancer, the U.S. Surgeon General, the U.S. Environmental Protection Agency, the U.S. National Cancer Institute, the U.S. Public Health Service, and virtually every other major public health organization and authority in the United States. These scientific authorities and the vast majority of studies of secondhand smoke have concluded that secondhand smoke is a cause of lung cancer, heart disease, chronic lung ailments such as bronchitis and asthma (particularly in children), and low birth-weight births. Like the new study, which is being published in the British Medical Journal, almost every study that has concluded secondhand smoke does not cause disease has been funded by the tobacco industry.

The new study must be placed in the context of the tobacco industry's long history of funding junk science aimed at discrediting legitimate studies about secondhand smoke and sowing doubt and confusion among the public, the media and policy makers. In fact, the tobacco industry organization that funded the new study – the Center for Indoor Air Research (CIAR) – was created for the very purpose of spearheading these deceptive industry efforts and was shut down by the state attorneys general as part of the 1998 state tobacco settlement. In January 29, 2003 court filings to support its racketeering lawsuit against the tobacco industry, the U.S. Department of Justice stated, 'CIAR was officially created … to act as a coordinating organization for Defendants' efforts to fraudulently mislead the American public about the health effects of ETS [environmental tobacco smoke] exposure.' The Justice Department also stated that CIAR 'was not only used for litigation and public relations, but it was [sp] also funded research designed not to find answers to health questions, but solely to attack legislative initiatives related to ETS exposure. Lawyers specifically engineered and constructed scientific studies to get results that would be useful for public relations, litigation, and legislative battles, as opposed to results that would assist the scientific community in further understanding the health effects of ETS exposure.' (Brackets added.)

It is a tremendous disservice to the public, the scientific community and the media that the tobacco industry's funding of the new study and the involvement of CIAR were disclosed only in the fine print at the end of the study. In addition to CIAR's involvement, the fine print also notes that one of the researchers 'conducted an epidemiological review for a law firm which has several tobacco companies as clients.'

The new study analyzed data from an American Cancer Society cancer prevention study and tracked 118,094 California adults from 1959 to 1998. The American Cancer Society has stated that its scientists repeatedly advised one of the researchers that using these data to study the effects of secondhand smoke would lead to unreliable results. According to the Cancer Society, 'The study suffers from a critical design flaw: the inability to distinguish people who were exposed to secondhand smoke from those who were not.' Among its methodological problems, the study used a flawed measure of exposure to secondhand smoke based on whether a non-smoker was married to a smoker in 1959, when smoking was much more pervasive than today and non-smokers were exposed to secondhand smoke in most workplaces and other settings. It did not collect information on other forms of exposure to secondhand smoke or fully track changes in exposure in the home over time. (For more information on the American Cancer Society's analysis, please contact David Sampson at 213-368-8523).

A larger and more recent study, which was also based on American Cancer Society data and began in the 1980s, when there was less exposure to secondhand smoke outside the home, clearly showed an increased risk of lung cancer and heart disease as a result of exposure to secondhand smoke. Other studies have reached similar conclusions. Based on a review of more than 3,000 studies, the International Agency for Research on Cancer (IARC), a branch of the World Health Organization, concluded in June 2002 that there is a 'statistically significant and consistent association between lung cancer risk in spouses of smokers and exposure to secondhand tobacco smoke from the spouse who smokes.' The IARC also found that 'epidemiological studies have demonstrated that exposure to secondhand tobacco smoke is causally associated with coronary heart disease.' (Summaries of studies on the health harms of secondhand smoke can be found at

It is not surprising that the new study is being published as a growing number of governments in the United States, Britain and around the world are enacting smoke-free indoor workplace policies to protect workers and customers from the dangers of secondhand smoke. In addition to protecting non-smokers, such measures are proven effective at preventing non-smokers from starting to smoke and spurring smokers to quit or reduce smoking, all of which reduce cigarette sales and hurt the tobacco industry's bottom line. State and local governments should act on the vast majority of studies showing the health harms of secondhand smoke, not on studies funded by the tobacco industry, and protect the public's right to breathe clean, smoke-free air.