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Short-term effects Some non-smokers are able to stay in a room with smokers for quite some time and notice little or no effects. For others, however, just a few minutes or an hour of exposure can make them feel quite ill. Persons with asthma can experience attacks brought on by smoking•, and by passive smoking • whether they are adults or children(•, •, •, supporting calls for a smoking ban•). Tobacco smoke is an allergen, and allergy sufferers can experience stuffy, runny noses, watery eyes, sneezing, coughing, wheezing, and all the other typical allergy symptoms within minutes of exposure. Some people with no known allergies and without asthma may cough in smoke-filled rooms, get headaches, feel nauseated, feel sleepy, and experience other ill effects. Many former smokers, and those who are trying to quit do not like to be around smoke as it can cause them to have cravings. Some people simply do not like the odor, which clings to hair and clothing. Many of these short-term effects terminate after the exposure ends. Repeated exposure, however, is believed to cause more serious long-term effects. Long-term effects A wide array of negative effects are often attributed, in whole or in part, to frequent, long term exposure to second hand smoke. The extent to which the smoke influences the development of these negative effects is the subject of much debate and controversy. Some of the symptoms which have been or are frequently attributed to second hand smoke include: Although the nature of passive smoking makes study design problematic, meta-analyses from around the world suggest that dangers of passive smoking are significant.• • • Passive smoking kills about 53,000 nonsmokers per year, making it the 3rd leading cause of preventable death in the U.S. Epidemiological studies of passive smoking Epidemiological studies suggest that non-smokers exposed to secondhand smoke are at risk for many of the health problems associated with direct smoking. In 1992, the Journal of the American Medical Association published a review of the evidence available from epidemiological and other studies regarding the relationship between secondhand smoke and heart disease and estimated that passive smoking was responsible for 35,000 to 40,000 deaths per year in the United States in the early 1980s.• Some studies make the claim that non-smokers living with smokers have about a 25 per cent increase in risk of death from heart attack, are more likely to suffer a stroke, and can sometimes contract genital cancer. Some research, such as the Helena Study, suggests that risks to nonsmokers may be even greater than this estimate. The Helena Study claims that exposure to secondhand smoke increases the risk of heart disease among non-smokers by as much as 60 percent. • Parents who smoke appear to be a risk factor for children and babies and are associated with low birth weight babies, sudden infant death syndrome (SIDS), bronchitis and pneumonia, and middle ear infections.• In 2002, a group of 29 experts from 12 countries convened by the Monographs Programme of the International Agency for Research on Cancer (IARC) of the World Health Organization (WHO) reviewed all significant published evidence related to tobacco smoking and cancer. It concluded: These meta-analyses show 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 excess risk is of the order of 20% for women and 30% for men and remains after controlling for some potential sources of bias and confounding.• Additionally, studies assessing passive smoking without looking at the partners of smokers have found that high overall exposure to passive smoking is associated with greater risks than partner smoking and is widespread in non-smokers•. The National Asthma Council of Australia• cites studies showing that: Environmental tobacco smoke (ETS) is probably the most important indoor pollutant, especially around young children: In France passive smoking has been shown to cause between 3000• and 5000 premature deaths per year, with the larger figure cited by Prime minister Dominique de Villepin during his announcement of a nationwide smoking ban: "That makes more than 13 deaths a day. It is an unacceptable reality in our country in terms of public health."• Studies of passive smoking in animals Experimental studies in which animals are exposed to tobacco smoke have produced results supporting the view that exposure to secondhand or 'environmental' tobacco smoke is carcinogenic. The International Agency for Research on Cancer expert group concluded that: There is limited evidence in experimental animals for the carcinogenicity of mixtures of mainstream and sidestream tobacco smoke. There is sufficient evidence in experimental animals for the carcinogenicity of sidestream smoke condensates.• A study conducted by the Tufts' School of Veterinary Medicine and the University of Massachusetts concluded that a cat living with a smoker is two times more likely to get feline lymphoma than one that is not. After five years living with a smoker, that rate increases to three times as likely. And, when there are two smokers in the home, the chances of getting feline lymphoma increases to four times as likely•. A study by Colorado State University found that a dog that has exposure to a smoker in the home is 1.6 times more likely to develop lung cancer than a dog that is not exposed to a smoker. The study also found that skull shape had an effect on the estimated risk of lung cancer in dogs.• Risk level of passive smoking The International Agency for Research on Cancer concluded in 2002 that: There is sufficient evidence that involuntary smoking (exposure to secondhand or 'environmental' tobacco smoke) causes lung cancer in humans. Involuntary smoking (exposure to secondhand or 'environmental' tobacco smoke) is carcinogenic to humans (Group 1).• Most experts believe that moderate, occasional exposure to secondhand smoke presents a small, but measurable cancer risk to nonsmokers. The risk is considered more significant if non-smokers work in an environment where cigarette smoke is prevalent, although few studies bear this out.• In May 2006, the United States government's Center for Disease Control issued its first new study on secondhand smoke in 20 years. Surgeon General Richard Carmona summarized, "The health effects of secondhand smoke exposure are more pervasive than we previously thought. The scientific evidence is now indisputable: secondhand smoke is not a mere annoyance. It is a serious health hazard that can lead to disease and premature death in children and nonsmoking adults." The study estimated that living or working in a place where smoking is permitted increases the non-smokers' risk of developing heart disease by 25-30% and lung cancer by 20-30%. The study finds that passive smoke also causes sudden infant death syndrome (SIDS), respiratory problems, ear infections and asthma attacks in children.• Environmental Tobacco Smoke and Particulate Matter Emission Environmental tobacco smoke (ETS) was shown to be a much higher source of pollution than an ecodiesel engine in regard to particulate matter (PM) emission. In fact three cigarettes smouldering in a room of 60 m3 with a limited air exchange, a setting commonly encountered in everyday life, were able to produce PM concentrations up to 10-fold that of the engine’s emissions, and up to 15-fold PM10 and PM2.5 outdoor limits, in agreement with previous data on ETS pollution observed in the hospitality industry.• Controversy Some controversy has attended efforts to estimate the specific risk of lung cancer related to passive smoking. In 1993, the US Environmental Protection Agency (EPA) issued a report estimating that 3,000 lung cancer related deaths in the U.S. were caused by passive smoking every year. The Congressional Research Service issued a report that generally endorsed the findings of the study,while noting that 'a few researchers have challenged the classification of ETS as a known carcinogen'. Among those testifying in favour of the tobacco industry at the inquiry was Congressman Thomas J Bliley, who had received more than $22,900 from tobacco companies in 1993-4, and more than $53,000 from them in 1995-1996. Philip Morris, R.J. Reynolds and groups representing growers, distributors and marketers took legal action, claiming that the EPA manipulated scientific studies and ignored accepted scientific and statistical practices. In 1998 United States District Court Judge William Osteen, a former tobacco lobbyist, vacated this study, declaring it null and void in a 92-page decision, that found that the EPA had manipulated results and violated scientific norms in order to achieve its pre-determined conclusion that passive smoke was harmful. Even though Osteen had worked as a lobbyist for the tobacco industry prior to becoming a judge, he had delivered a ruling contrary to the interests of tobacco companies in 1997 he had refused to strike down a FDA rule restricting young people's access to tobacco products. Osteen's decision was overturned by the United States Court of Appeals for the Fourth Circuit in 2002 on the technical grounds that the report was not a reviewable agency action under the Administrative Procedure Act, and the EPA classification of tobacco was ultimately left intact. Because the substantive dispute was never resolved, the findings in Osteen's report are still used to argue that the issue of ETS is driven by politics rather than science. Enstrom and Kabat Two recent studies by Enstrom and Kabat•• conclude that the previous studies overestimated the effect of Environmental Tobacco Smoke (ETS) on both lung cancer and heart diseases. These studies have been criticised by the American Cancer Society, which describes the study as "misinformation", on the grounds that both the original cohort and Enstrom and Kabat's follow-ups, were inappropriate for reliably determining ETS exposure, smoking history, etc. Furthermore, Enstrom and Kabat are funded by the tobacco industry.•. Enstrom and Kabat have rejected this criticism, claiming that the American Cancer Society funded most of the first study, but pulled their funding at the last minute, forcing the researchers to look elsewhere to find funding. Further, they say were only able to find funding from a foundation funded by the tobacco companies. In response, ACS vice-president Michael Thun• asserts that Enstrom had been funded by the tobacco industry since 1997 without informing the ACS, and that Enstrom had communicated with Philip Morris about the potential value of the CPS-I follow-up as early as 1990.• The study also attracted criticism for a number of methodological flaws: In addition, Enstrom and Kabat's work confirmed some harmful effects of secondhand smoke, in particular that it increased the risk of Chronic Obstructive Pulmonary Disease (COPD)•. The link between tobacco industry funding and the results of studies on the nature of passive smoking was investigated in a literature review by Barnes & Bero, who found that the only factor affecting the conclusions of epidemiological studies of passive smoking was whether the authors had recieved funding from the tobacco industry or not •. ASH published an analysis of the studies that concluded that the studies cannot be trusted, as there appears to be a direct conflict of interest. Alongside other faults, this analysis also criticizes the BMJ for failing to inform readers who funded the studies.• Tobacco industry response The passive smoking issue poses a serious economic threat to the tobacco industry. It has broadened the definition of smoking beyond a personal habit to something with a social impact, it has been the cause of successful litigation against employers by workers with a history of exposure to smoke, and it has resulted in various types of smoking restrictions. Accordingly, the tobacco industry have developed several strategies to minimise its impact on their business: Smoking bans See also: Smoking bans, List of smoking bans As a consequence of the perceived dangers of passive smoking, a general ban on smoking in all establishments serving food and drink, including restaurants, cafés, and nightclubs, was introduced in Norway on June 1, 2004, and in Sweden on June 1, 2005, and many parts of America, including the states of Florida, California and New York, have similar legislation in place. These initial bans have grown in scope, with countries (such as Ireland and Scotland), jurisdictions (like New York State, Washington State, and Arkansas in the US) now prohibiting smoking in public buildings as well as private businesses such as restaurants and clubs. Many office buildings contain specially ventilated smoking areas; some are required by law to provide them. Some regions and local governments have banned smoking in all workplaces, in taxicabs, and in ventilated smoking rooms or enclosed smoking shelters such as those found in front of hospitals. Even in countries traditionally seen as nations of smokers, opinion polls have shown support for bans, with 70% of those in France supporting a ban. In the first 18 months after the town of Pueblo, Colorado enacted a smoking ban in 2003, hospital admissions for heart attacks dropped 27%. Admissions in neighboring towns without smoking bans showed no change. The American Heart Association said, "The decline in the number of heart attack hospitalizations within the first year and a half after the non-smoking ban that was observed in this study is most likely due to a decrease in the effect of secondhand smoke as a triggering factor for heart attacks." Heart attacks decline after smoking bans CNN.com accessed 9/26/2006 Notes | |||||||||
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