User:MastCell/Passive smoking draft

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Contents 1 Controversy over harms of passive smoking 1.1 Critique of individual studies and epidemiology 1.2 World Health Organization controversy 1.3 EPA lawsuit 1.4 Tobacco-industry funding of research 1.5 Public opinion 1.6 Current state of controversy 2 References

Controversy over harms of passive smoking

In 1986, responding to growing evidence of the harms of passive smoking, the United States Surgeon General issued a report concluding that secondhand smoke was a cause of disease. In the same year, the International Agency for Research on Cancer and the National Research Council also released reports concluding that secondhand smoke was a cause of lung cancer.^[1] Over the subsequent 20 years, the accumulation of scientific evidence has led to a scientific consensus that passive smoking is indeed harmful to non-smokers.^[2] A U.S. District Court found, in a racketeering case against the tobacco industry, that the industry had internally acknowledged the harmfulness of passive smoking even earlier.^{[3], pp. 1523–1525} Nonetheless, the tobacco industry has played a central role in generating and sustaining controversy over the effects of passive smoking.^[4][5]

Critique of individual studies and epidemiology

A number of studies funded by the tobacco industry have yielded results inconsistent with the scientific consensus, or have criticised the epidemiological approach associated with that consensus.

A 2003 study by Enstrom and Kabat, published in the British Medical Journal, argued that the harms of passive smoking had been overstated.^[6] Their analysis reported no statistically significant relationship between passive smoking and lung cancer, though the accompanying editorial noted that "they may overemphasise the negative nature of their findings."^[7] This paper was widely promoted by the tobacco industry as evidence that the harms of passive smoking were unproven.^{[3], p. 1383} The American Cancer Society (ACS), whose database Enstrom and Kabat used to compile their data, criticized the paper as "neither reliable nor independent", stating that scientists at the ACS had repeatedly pointed out serious flaws in Enstrom and Kabat' s methodology prior to publication.^[8] Enstrom's ties to the tobacco industry also drew scrutiny; in a 1997 letter to Philip Morris, Enstrom requested a "substantial research commitment... in order for me to effectively compete against the large mountain of epidemiologic data and opinions that already exist regarding the health effects of ETS and active smoking."^[9] The study was funded and managed by the Center for Indoor Air Research, a tobacco industry front group, and Enstrom's work was viewed by Philip Morris as "clearly litigation-oriented."^{[3], pp. 1380–1383}

Gio Batta Gori, a full-time tobacco-industry consultant,^[10] wrote in the libertarian Cato Institute's journal Regulation that "...of the 75 published studies of ETS and lung cancer, some 70 percent did not report statistically significant differences of risk and are moot. Roughly 17 percent claim an increased risk and 13 percent imply a reduction of risk."^[11] Steven Milloy, the "junk science" commentator for Fox News and a former Philip Morris consultant,^[12][13] claimed that "...of the 37 studies [on passive smoking], only 7 – less than 19 percent – reported statistically significant increases in lung cancer incidence."^[14]

Another component of criticism promoted by Milloy focused on relative risk and epidemiological practices in studies of passive smoking. Milloy argued that studies yielding relative risks of less than 2 were meaningless junk science. This approach to epidemiological analysis was criticized in the American Journal of Public Health:

A major component of the industry attack was the mounting of a campaign to establish a "bar" for "sound science" that could not be fully met by most individual investigations, leaving studies that did not meet the criteria to be dismissed as "junk science."^[15]

The tobacco industry and affiliated scientists also put forward a set of "Good Epidemiology Practices" which would have the practical effect of obscuring the link between secondhand smoke and lung cancer. However, this effort was largely abandoned when it became clear that no independent epidemiological organization would agree to the standards proposed by Philip Morris et al.^[16]

World Health Organization controversy

A 1998 report by the International Agency for Research on Cancer (IARC) on environmental tobacco smoke (ETS) found "weak evidence of a dose-response relationship between risk of lung cancer and exposure to spousal and workplace ETS."^[17] In March of 1998, before the study was published, reports appeared in the media alleging that the IARC and the World Health Organization (WHO) were suppressing information. The reports, appearing in the British Sunday Telegraph^[18] and The Economist,^[19] among other sources,^[20][21][22] alleged that the WHO withheld from publication its own report that supposedly failed to prove an association between passive smoking and a number of other diseases (lung cancer in particular).

In response, the WHO issued a press release stating that the results of the study had been "completely misrepresented" in the popular press and were in fact very much in line with similar studies demonstrating the harms of passive smoking.^[23] The study was published in the Journal of the National Cancer Institute in October of the same year. An accompanying editorial summarized:

When all the evidence, including the important new data reported in this issue of the Journal, is assessed, the inescapable scientific conclusion is that ETS is a low-level lung carcinogen.^[24]

With the release of formerly classified tobacco industry documents through the Tobacco Master Settlement Agreement, it was found that the controversy over the WHO's alleged suppression of data had been engineered by Philip Morris, British American Tobacco, and other tobacco companies in an effort to discredit scientific findings which would harm their business interests.^[25] A WHO inquiry, conducted after the release of the tobacco-industry documents, found that this controversy was generated by the tobacco industry as part of its larger campaign to cut the WHO's budget, distort the results of scientific studies on passive smoking, and discredit the WHO as an institution. This campaign was carried out using a network of ostensibly independent front organizations and international and scientific experts with hidden financial ties to the industry.^[26]

EPA lawsuit

In 1993, the United States Environmental Protection Agency (EPA) issued a report estimating that 3,000 lung cancer related deaths in the U.S. were caused by passive smoking annually.^[27] Philip Morris, R.J. Reynolds Tobacco Company, and groups representing growers, distributors and marketers of tobacco took legal action, claiming that the EPA had manipulated this study and ignored accepted scientific and statistical practices.

A United States District Court ruled in favor of the tobacco industry in 1998, finding that the EPA had failed to follow proper scientific and epidemiologic practices and had committed to their conclusions in advance.^[28] In 2002, the EPA successfully appealed this decision to the United States Court of Appeals for the Fourth Circuit. The EPA's appeal was upheld on the preliminary grounds that their report had no regulatory weight, and the earlier finding was vacated.^[29]

Tobacco-industry funding of research

The tobacco industry's role in funding scientific research which "exonerates" passive smoking has been controversial, although a focus on the funding source of studies has been criticized as ad hominem.^[30] A review of published studies found that tobacco-industry affilation was strongly correlated with findings exonerating passive smoking; researchers affiliated with the tobacco industry were 88 times more likely than independent researchers to conclude that passive smoking was not harmful.^[31] In a specific example which came to light with the release of tobacco-industry documents, Philip Morris executives successfully encouraged an author to revise his industry-funded review article to downplay the role of secondhand smoke in sudden infant death syndrome.^[32] The 2006 U.S. Surgeon General's report criticized the tobacco industry's role in the scientific debate:

The industry has funded or carried out research that has been judged to be biased, supported scientists to generate letters to editors that criticized research publications, attempted to undermine the findings of key studies, assisted in establishing a scientific society with a journal, and attempted to sustain controversy even as the scientific community reached consensus.^[33]

This strategy was outlined at an international meeting of tobacco companies in 1988, at which Philip Morris proposed to set up a team of scientists, organized by company lawyers, to "carry out work on ETS to keep the controversy alive."^[5] All scientific research was subject to oversight and "filtering" by tobacco-industry lawyers:

Philip Morris then expect the group of scientists to operate within the confines of decisions taken by PM scientists to determine the general direction of research, which apparently would then be 'filtered' by lawyers to eliminate areas of sensitivity.^[5]

Philip Morris reported that it was putting "...vast amounts of funding into these projects... in attempting to coordinate and pay so many scientists on an international basis to keep the ETS controversy alive."^[5]

Public opinion

Recent major surveys conducted by the U.S. National Cancer Institute and Centers for Disease Control have found widespread public acceptance of the harms of secondhand smoke. In both 1992 and 2000 surveys, more than 80% of respondents agreed with the statement that secondhand smoke was harmful. A 2001 study found that 95% of adults agreed that secondhand smoke was harmful to children, and 96% considered tobacco-industry claims that secondhand smoke was not harmful to be untruthful. A 2004 Gallup poll found that 86% of respondents felt that secondhand smoke was "very harmful" or "somewhat harmful", while 4% felt that it was not harmful at all.^{[34], p. 588} Smoking bans had somewhat less support; the 2004 Gallup poll found 58% in favor of total smoking bans in workplaces, restaurants, and bars, while 40% opposed such across-the-board bans.^{[34], p. 589}

Current state of controversy

Currently, there is widespread scientific consensus that exposure to secondhand smoke is harmful.^[3] The link between passive smoking and health risks is accepted by every major medical and scientific organization, including:

• The World Health Organization^[35]
• The U.S. National Institutes of Health^[36]
• The Centers for Disease Control^[37]
• The United States Surgeon General^[38]
• The U.S. National Cancer Institute^[39]
• The United States Environmental Protection Agency^[40]
• The American Heart Association,^[41] American Lung Association,^[42] and American Cancer Society^[43]
• The American Medical Association^[44]
• The Australian National Health and Medical Research Council^[45]
• The United Kingdom Scientific Committee on Tobacco and Health^[46]
• The governments of 150 nations have signed and ratified the World Health Organization Framework Convention on Tobacco Control, which states that "Parties recognize that scientific evidence has unequivocally established that exposure to tobacco smoke causes death, disease and disability."^[47]

While there is scientific agreement regarding the existence of a link between passive smoking and heart disease, the magnitude of the increased risk remains debated by a minority of epidemiologists.^[48] For example, John Bailar of the National Academy of Sciences questioned the proportionality of the passive smoking risk, stating:

Regular smoking only increases the risk of cardiovascular disease by 75%, so how could second-hand smoke, which is much more dilute, have an effect one-third that size?

One proposed explanation is that secondhand smoke is not simply a diluted version of "mainstream" smoke, but has a different composition with more toxic substances per gram of total particulate matter.^[48] The more toxic makeup of secondhand smoke was first recognized in the tobacco industry's own research, though it never published its findings.^[49] Some scientists believe that the risk of passive smoking, in particular the risk of developing coronary heart diseases, may have been substantially underestimated.^[50]

The health benefit to non-smokers of smoking bans has also been disputed by a small number of epidemiologists, who call for a prospective trial to more accurately determine the benefit. These epidemiologists advocate indoor smoking bans, but express a concern that widespread outdoor smoking bans, as implemented by some towns in the U.S., may be unsupported by the evidence available thus far.^[48]

References