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APPENDIX ENVIRONMENTAL TOBACCO SMOKE: A GUIDE TO WORKPLACE SMOKING POLICIES (Tobacco Institute Substitute Text) INTRODUCTION Environmental tobacco smoke ("ETS") is a controversial subject and a matter of debate among government officials, health scientists, ventilation engineers and the general public. Although many studies have been performed, the science of ETS is still in its infancy. Many questions remain unanswered, including questions regarding the health effects, if any, of exposure to ETS. This Policy Guide is intended to provide government and private sector decision makers with information about what is known -- and not known -- about ETS. Chapter One explains what is meant by the term "environmental tobacco smoke." ETS is not the same as the tobacco smoke inhaled by smokers. Rather, it is a complex, highly diluted mixture of exhaled mainstream and sidestream smoke that decays quickly after initial formation, depending upon ventilation and other factors. Chapter Two examines the issues relevant to accurate measurement of exposure to ETS. In order to assess the impact of exposure to ETS or any other substance, scientists first

- 2 - must obtain accurate measurements of its existence and quantity in the air and body. Because of its complexity, ETS is difficult to measure. In fact, the methods that have been used thus far are the subject of considerable controversy. Until more accurate measurement techniques become available, definitive conclusions about ETS must be regarded with skepticism. Chapter Three explores the health effects some claim are associated with exposure to ETS. ETS and its possible association with lung cancer, cardiovascular disease, and respiratory effects have been widely studied in recent years. When critically examined and evaluated, the published data do not demonstrate that ETS causes disease in nonsmokers. Much more research is required before the chronic health effects of ETS, if any, are fully understood. The final chapter evaluates ETS in the context of the larger issue of indoor air quality. Government and private sector experts have discovered that ETS in the workplace usually is merely a symptom of an invisible problem, not a cause. Building occupants suffering from sore eyes, itchy throats and other symptoms of "sick building syndrome" often wrongly attribute their problems to ETS because it is the most visible component of indoor air. Upon investigation, a hidden source -- usually related to poorly maintained and inadequate ventilation systems -- is revealed. The first step for any employer confronted with complaints about ETS or any I other source of indoor air contamination is to make sure that

- 3 - ventilation is-adequate.and the heating and cooling system is well maintained. Chapter 1: What is ETS? Environmental tobacco smoke, or ETS, has been widely misunderstood. Some believe it is simply tobacco smoke in room air, indistinguishable from the smoke inhaled directly by a smoker. In fact, ETS is quite different. ETS is a complex, highly diluted mixture that decays rapidly after initial formation depending upon ventilation and various other factors. ETS originates primarily from the smoke emitted from the burning end of a cigarette. This is known as "sidestream" smoke. Sidestream smoke differs in both composition and concentration from the "mainstream" smoke directly inhaled by the smoker. Overall, environmental tobacco smoke consists of sidestream smoke, plus exhaled mainstream smoke, together with minor amounts of smoke that escape during the puff, and some vapor that diffuses through the cigarette paper.l/ Although smoke from cigarettes is the most frequently encountered and studied, ETS can be derived from cigars and pipes as well. Once ETS is released into a room, a number of processes occur that significantly alter its physical and chemical properties. These processes are known as "aging." In addition to aging, the key process in the evolution of ETS 1/ Reasor, M.J. (1987). The composition and dynamics of environmental tobacco smoke. J. of Environ. Health 50:20-24.

4 is dilution of the smoke with room air. Typically, dilution of smoke with room air is rapid and extensive, depending on such factors as room size and the ventilation rate. Because the components of ETS decay at different rates, the absolute and relative concentrations of ETS constituents are constantly changing. If a group of ETS components is measured five minutes after a cigarette is smoked and then again fifteen minutes later, the overall concentration levels will have decreased and the relative levels of each component will have altered. In addition, most of the components of ETS can be found in the air from sources other than tobacco smoke, including cooking and motor vehicle exhausts, as well as building materials and furnishings. The concentration levels of many ETS components are so small that they cannot be easily measured. As a result, the chemical and physical properties of ETS have not yet been precisely defined. Because undiluted sidestream smoke can be collected relatively easily and its composition ascertained, some investigators have used it as a surrogate or substitute for ETS. As a substitute for ETS, however, sidestream smoke has little value. ETS is both quantitatively and qualitatively distinct from sidestream cigarette smoke. Nor can ETS be compared to mainstream smoke. ETS is qualitatively different both in composition and physical characteristics from the mainstream smoke to which an active smoker is exposed. The components of mainstream smoke are

- 5 - -many times more concentrated than those of ETS. Nicotine, for example, is relatively concentrated in mainstream smoke but dissipates rapidly when diluted with air. In addition, inhaling mainstream smoke directly from a cigarette through the mouth is different from breathing ETS (typically through the nose). Thus, inhalation of ETS cannot be characterized accurately as "passive smoking."?/ ETS is not a major cause of the indoor air contamination that has been found to produce the various illnesses collectively known as "sick building" syndrome. It is a symptom rather than a cause of poor indoor air quality. According to the U.S. National Institute for Occupational Safety and Health (NIOSH), for example, only two percent of the buildings inspected in response to occupant complaints about poor indoor air quality involved questions of tobacco smoke. Almost half of the complaints were traced to inadequate ventilation. In many other cases, air quality was affected adversely by chemicals from duplicating machines, carbon monoxide from basement parking garages and bacteria found growing in ventilation or heating systems.3/ Some 2/ Balter, N.J., et al. (1986). Causal relationship between ETS and lung cancerin nonsmokers: A critical review of the literature. Proc. Air Poll. Control Assoc. 3/ Melius, J., Wallingford, K., Keenlyside R., and J. Carpenter, "Indoor Air Quality -- The NIOSH Experience," Presentation to the American Society of Heating, Refrigeration & Air Conditioning Engineers, Atlanta, Ga. (April 1985) [hereinafter cited as "NIOSH Study"].

- 6 - people erroneously attribute their discomfort indoors to ETS because of its visibility. Upon investigation, a hidden source is usually revealed.4/ ETS is a very complex substance. Only through an accurate appreciation of what ETS is -- and is not -- can the real problems of indoor air quality be understood and can appropriate measures be taken to guarantee acceptable air quality for everyone, smokers and nonsmokers alike. Chapter 2: Measuring ETS In order to assess the impact of exposure to ETS, one must first obtain accurate measurements of its existence and quantity in the air and body. Obtaining such measurements is a difficult process, especially in light of the complex nature of ETS itself. As discussed in the previous chapter, ETS is a mixture of numerous substances that can change rapidly over a short period. Most, if not all, of these constituents react differently to heat, light, and other constituent substances, and decay at different rates. All of these constituents are otherwise present in some aspect of the environment, whether in food, fuels, building materials or furniture. Attributing these constituents in the air or body to ETS is no easy task. 4/ Robertson, G., (1990). Indoor pollution: Sources, effects and mitigation strategies. In Environmental Tobacco Smoke: Proceedings of the International Symposium at McGill Un ersity, (Eds., Ecobichon, D.J. and Wu, J.M., Lexington Books, Lexington, Mass. 333-356 [hereinafter cited as "McGill Symposium"J.

- 7 - Given these difficulties, it is not surprising that the methods used for measuring ETS are the subject of considerable controversy. Generally, ETS investigators use one or a combination of four measurement methods. To measure ETS in air, scientists collect samples of air at a fixed sampling location or via a mobile monitoring instrument (ideally, placed as close to the breathing zone as possible). To measure ETS in the body, scientists collect samples of body fluids such as blood, urine or saliva (so-called "biological monitoring"). To measure the overall impact of ETS, researchers use data obtained from questionnaires asking people about their exposure. To estimate the degree of exposure that might occur in a particular airspace, statisticians construct mathematical models. So far, none of these methods has provided a fully reliable way of measuring ETS. At present, neither fixed-area air monitors nor portable gauges carried by individuals are able to measure all the components of ETS in air. Instead, these devices measure well-known constituents as "surrogates" for ETS. The three surrogates most often used are carbon monoxide, respirable suspended particulates and nicotine. However, carbon monoxide and RSP are poor ETS surrogates because they are not specific to tobacco. Both are produced by many sources other than ETS, including cooking, heating, construction and automobile

8 traffic and dust arising from human activity.5/ The third surrogate -- nicotine -- is somewhat more specific to ETS, although it too can be found in certain food products.6/ Nicotine is, moreover, a highly volatile substance with a relatively rapid decay rate as compared to other ETS constituents.2/ Thus nicotine -- like carbon monoxide and particulate matter -- is far from an ideal surrogate for measuring ETS in air. Most studies assessing the impact of ETS on the basis of air monitoring fail to take account of the problems associated with these surrogates, particularly with respect to background levels of substances present in indoor 5/ Goodfellow, H., S. Eyre, and J.A.S. Wyatt (1990). Assessing exposures to environmental tobacco smoke. In McGill Symposium at 53-67. 6/ Idle, J.R. (1990). Titrating exposure to tobacco smoke using cotinine: A minefield of misunderstandings. J. Clin. Epidemiol. 43;313-317; Sheen, S.J. (1988). Detection of nicotine in foods and plant materials. J. Food Sci. 53: 1572-1573; castro, A. and N. Monji (1986). Dietary nicotine and its significance in studies on tobacco smoking. Biochem. Arch. 2:91-97. 7/ Editorial (1989). Environmental tobacco smoke in the context of indoor air quality. Human Toxicol. 8:3-4; Baker, R. and S. Colome (1988). The build-up and decay of environmental tobacco smoke constituents as a function of room conditions. Proc. Indoor Amb. Air Qual. Conf., London; Muramatsu, M., et al. (1987). Estimation of personal exposure to ambient nicotine in daily environment. Int'l Arch. Occup. Envir. Health 49:545-550.

- 9 - environments.8/ Under these circumstances, the conclusions of such studies are highly suspect.9/ Similar problems exist with respect to biological monitoring. Here, the majority of studies test for the presence of cotinine -- a metabolite of nicotine -- in bodily fluids. Again, however, cotinine is not wholly tobacco- specific.10/ In addition, the rates at which individuals metabolize nicotine and eliminate cotinine from their bodily fluids vary widely, making it difficult to interpret comparisons of cotinine levels. Although some promising work is being done to develop other biological surrogates for 8/ Recent studies indicate that ultraviolet particulate matter may be a promising surrogate for the particulate phase of ETS. See Conner, J.M., G.B. Oldaker III, and J.J Murphy (1990). Method for assessing the contribution of environmental tobacco smoke to respirable suspended particles in indoor environments. Environ. Technol. 11:189-196; Carson, J.R. and C.A. Erikson (1988). Results from a survey of environmental tobacco smoke in offices in Ottawa, Ontario. En viron. Tech. Lett. 9: 501-508. 9/ Sterling, T.D. and B. Mueller (1989). Concentrations of nicotine, RSP, CO and CO in nonsmoking areas of offices ventilated by air recirchated from smoking designated areas. Am. Ind. Byg. Assoc. J. 49:423-26; Sterling, T.D., C.W. Collet and E.M. Sterling (1987). Environmental tobacco smoke and indoor air quality in modern office work environments. J. Occup. Ned. 2 9: 5 7-6 2. 10/ Idle, J.R. (1990). Titrating exposure to tobacco smoke using cotinine: A minefield of misunderstandings. J. Clin. Epidemiol. 43:313-317.

ETS,11/ the results of recent biological studies cannot be accepted with confidence. Questionnaires provide information from which researchers have attempted to estimate past exposures to ETS. However, questionnaires about ETS exposure are subject to the same biases and infirmities that plague polling on any other subject. Most people have memories that are less than 100% accurate; people often provide answers based on what they think the interviewer wants to hear; interviewers sometimes select non-representative respondents or phrase questions in a way that precludes communication of relevant information. One bias, for example, that is consistently cited in connection with ETS questionnaires is under-reporting of active smoking by professed "nonsmokers."12/ Studies based on such questionnaires cannot by themselves be relied upon accurately to measure exposure to ETS. Finally, mathematical modeling has been employed in an effort to extrapolate from certain assumptions and predict ETS exposure within a given airspace. However, the assumptions upon which such models are based are typically unrealistic. For example, most models assume that smoke is 11/ Reasor, M.J. (1990). Biological markers in assessing exposure to environmental tobacco smoke. In McGill Symposium at 69-77. 12/ Lee, P.N. Passive smoking and lung cancer: fact or Y'Iction? in Present and Future of Indoor Air Qualit (Eds. Bieva et al.), Excerpta Me ica, Amster am; Lee, P.N. (1987). Lung cancer and passive smoking. Toxicol. Letters 35:157-162.