Annals of Occupational Hygiene Advance Access originally published online on March 1, 2006
Annals of Occupational Hygiene 2006 50(4):331-341; doi:10.1093/annhyg/mel011
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Original Article |
Environmental Tobacco Smoke in Finnish Restaurants and Bars Before and After Smoking Restrictions were Introduced
Finnish Institute of Occupational Health, Uusimaa Regional Institute, Arinatie 3A, FI–00370 Helsinki, Finland
* Author to whom correspondence should be addressed. Tel: +358-30-4742965; fax: +358-9-5061087; e-mail: Tom.Johnsson{at}ttl.fi
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ABSTRACT |
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 TOP ABSTRACT INTRODUCTIONMATERIALS AND METHODSRESULTS AND DISCUSSIONCONCLUSIONSACKNOWLEDGEMENTSREFERENCES |
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Objectives: The Finnish Tobacco Act was amended on 1 March 2000 to include restrictions on smoking in restaurants and bars. To evaluate the effectiveness of the restrictions, environmental tobacco smoke (ETS) concentrations in restaurants and bars were measured prior and after the amended Act entered into force. The Act was enforced in stages so that all stages were effective on 1 July 2003. According to the Act, smoking is prohibited in all Finnish restaurants and bars with certain exceptions. Smoking may be allowed in establishments where the service area is not larger than 50 m2 if the exposure of employees working there to ETS can be prevented. On premises with larger service area, smoking may be allowed on 50% of the service area, provided tobacco smoke does not spread into the area where smoking is prohibited. At bar counters or gambling tables smoking is not allowed, if the spreading of tobacco smoke cannot be restricted to the employee side of the counter. Therefore, according to the Act all areas where smoking is prohibited are to be smoke-free. Methods: Establishments with a serving area larger than 100 m2 were selected for the present study. The evaluation both before and after the enforcement of the Act included the following: The ventilation rate was first measured in each establishment. Then 3–5 area samplers, depending on the layout, were placed in locations that best described the establishment and the working areas of the personnel. The measurements were performed twice at each establishment, during peak hours. The sample collection time was 4 h during which the guests and the cigarettes smoked were counted. The air samples were analysed for nicotine, 3-ethenylpyridine (3-EP) and total volatile organic compounds (TVOC) by thermodesorption–gas chromatography–mass spectrometry. Results: Altogether 20 restaurants and bars situated in three Finnish cities participated in the study out of which 16 participated during all four measurement periods. None of the establishments had introduced a total ban on smoking and they all had reserved only the smallest area allowed by the Finnish Tobacco Act as the smoke-free area. The measured geometric mean (GM) nicotine concentration in all participating establishments was 7.1 µg m–3 before the amended act was in force and 7.3 µg m–3 after all stages of the Act had been enforced. The GM concentration of nicotine in food and dining restaurants was 0.7 µg m–3 before and 0.6 µg m–3 after the enforcement of the Act, in bars and taverns the concentrations were 10.6 and 12.7 µg m–3, and in discos and night-clubs 15.2 and 8.1 µg m–3, respectively. The GM nicotine concentrations measured in the smoke-free sections varied between 2.9 and 3 µg m–3. 3-EP concentrations measured correlated well with the nicotine concentrations and were approximately one-fifth of the nicotine concentrations. The measurements showed higher TVOC values in the smoking sections than in the smoke-free sections, but because there are many other sources of TVOC compounds in restaurants and bars TVOC cannot be regarded as a marker for ETS. Conclusions: The overall air nicotine concentration decreased in 10 out of the 18 establishments that participated in the study both before and after all stages of the amended Act had been in force. Structural changes or changes to the ventilation systems had been carried out in nine of these establishments, i.e. the smoke-free sections were actually non-smoking and were mainly separated from other sections by signs and very little was done to keep the smoke from spreading into the smoke-free sections. In four establishments, the highest air nicotine concentration was measured in the smoke-free section. In 10 establishments, the air nicotine concentration at bar counters had dropped after the Act. Exposure of the workers and the public to ETS was, therefore, not reduced as intended by the Finnish legislature. Thus, it seems obvious from the present study that improving ventilation will not be a solution to restricting tobacco smoke from reaching smoke-free areas and physical barriers separating smoking from smoke-free areas are required.
Keywords: environmental tobacco smoke • nicotine • restaurants and bars • smoking restrictions • Tobacco Act
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INTRODUCTION |
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TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTS AND DISCUSSIONCONCLUSIONSACKNOWLEDGEMENTSREFERENCES |
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In the hospitality industry workers are exposed to environmental tobacco smoke (ETS) at higher concentrations and for longer periods of time than other worker groups typically (Siegel, 1993
). It has been estimated that the mortality due to ETS exposure at work in Finland was 0.9% of the total mortality of the Finnish population in the relevant disease and age categories in the year 1996. Approximately 8% of the workforce were passive smokers in 1998–2000 (Nurminen and Jaakkola, 2001). In a recent paper Jamrozik (2005) estimated that 617 employed people in the UK die owing to passive smoking each year, including 54 worker deaths in the hospitality industry each year.
In Finland smoking restrictions concerning other workplaces than restaurants and bars were introduced into the Tobacco Control Act in 1995 and have proven effective (Heloma et al., 2000). The Finnish Tobacco Control Act originally from 1977 was amended to include restaurants and bars in the year 2000, and now classify tobacco smoke as a carcinogen. Smoking is now prohibited in restaurants, bars, gambling premises and corresponding establishments unless the exposure of employees working there to ETS can be prevented otherwise. The Act was enforced gradually so that on the 1st of March 2000, 70% of the serving area could be reserved for smokers in establishments larger than 100 m3, provided the tobacco smoke does not spread into the smoke-free sections. ‘Smoke-free’ is used throughout this paper to describe the non-smoking areas of the clientele area as well as the employee areas e.g. bar counters and gambling tables of the establishments studied. Starting 1 July 2001, establishments with a client area larger than 50 m2 could reserve a maximum of 50% of the serving area for smokers, again provided the smoke does not spread to smoke-free sections. Bar counters and gambling premises in all establishments have to be free of tobacco smoke. If simple structural or ventilation measures are not enough to control the spread of tobacco smoke to the smoke-free sections, other more extensive alterations could be made until 1 July 2003.
This study was launched to assess the impact of the amended Tobacco Control Act on ETS concentration in restaurants and bars. ETS concentration in the target restaurants and bars was measured by determining nicotine, 3-ethenylpyridine (3-EP), and total volatile organic compounds (TVOC) in air at fixed locations in 
20 establishments during each study period. The survey consisted of four measurement periods. One prior to the passage of legislation restricting smoking, the second when at least 30% of the service area had to be reserved for non-smoking customers, the third when at least 50% of the service area had to be reserved for non-smoking customers and the fourth after the more extensive alterations had to be completed on the 1st of July 2003.
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MATERIALS AND METHODS |
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TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTS AND DISCUSSIONCONCLUSIONSACKNOWLEDGEMENTSREFERENCES |
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The first study period was carried out from September 1999 to December 1999, the second from October 2000 to March 2001, the third from October 2001 to April 2002 and the fourth from October 2003 to March 2004. All measurement periods occurred during the wintertime in Finland, which enables comparison of results, because the ventilation was dependent solely on mechanical ventilation present in all establishments. Establishments with a service area larger than 100 m2 were selected for the study by contacting the owners directly during summer and autumn 1999. Additional selection criteria included: the mechanical ventilation systems of the premises could be measured, smoking was allowed in the premises, and the different compartments of an establishment were not completely separated from other areas by physical barriers, i.e. one-room establishments were preferred.
Depending on the clientele, the frequency and degree of smoking differs. Therefore, establishments of three different types were selected. One type denoted, as pubs in this paper include typical pubs, bars and taverns. Another group of establishments was nightclubs, which also include discos. The third group was the dining restaurants where food was the main attraction. To get a broader view of the situation in Finland the establishments were selected from three Finnish cities: Helsinki, Lappeenranta and Jyväskylä. The selection process of the chosen establishments was not truly random and the study locations selected reflect the views of a hospitality management professional with local knowledge of the cities studied.
The survey periods consisted of three phases: (i) the selection and inspection phase explained above; (ii) ventilation measurement phase; and (iii) monitoring phase. The second phase was conducted during the same week as the monitoring phase and included: measurement of the amount of air leaving and/or entering the establishment, and measurement of the area and volume of the premises. The total amount of air leaving or entering the premises was measured by either balometers or rotating vane anemometers and was performed by a ventilation engineer. In addition, the locations of the air-sampling monitors were decided upon during phase two. Three to five locations per establishment were selected. Criteria for the sampling locations were the following: Describes the entire space as well as possible, at least one at the bar counter(s), at least one in the smoke-free and one in the smoking sections (not applicable before legislation was passed). The sampling devices were placed at a height of 1.4–1.7 m above the floor, approximately at the breathing zone level of employees and customers. During the second survey period, after the legislation restricting smoking had been enforced, the same locations for the area monitoring were used if possible and additional locations were added to meet the criteria for at least one sampling location in the smoke-free and the smoking sections. The monitoring phase included air sampling for a 4 h period during peak hours. Once during the week and once during the weekend (Friday or Saturday evenings). During the monitoring period the customers were counted every hour and the cigarette butts were collected to estimate the amount of cigarettes smoked during the sampling time. The air monitor consisted of a sampling pump SKC Model 222 (SKC Inc, Eighty Four, PA, USA) collecting air at 100 cm3 min–1 through a stainless steel tube (Part no. L4270123, Perkin Elmer, Norwalk, CT, USA) packed with 150 mg Tenax TA 35/60 mesh (Art 706216, Macherey-Nagel GmbH & Co. KG, Düeren, Germany). The sample analysis has been described in a previous publication (Rothberg et al., 1998). Briefly, the samples were desorbed at 300°C and analysed for nicotine and 3-EP by thermodesorption–gas chromatography–mass spectrometry. The measured TVOC, nicotine and 3-EP concentration represent the average concentration during the 4 h period. For samples with nicotine and 3-EP concentrations below the limit of quantitation (0.05 µg m–3) we used 0.025 µg m–3 for calculations. Theoretical average nicotine concentrations in air were calculated based on the air exchange rate and cigarettes smoked (Daisey, 1999; Ott, 1999; Repace, 2005).
 | (1) |
= average concentration (µg m–3); nave = burned cigarettes during averaging time; gcig = cigarette emission [1800 µg nicotine per cigarette (Repace et al., 1998)]; 
c = change of concentration over the averaging time; 
= air exchange rate (1 h–1); V = Volume of establishment (m3); and T = averaging time (4 h).
Because the measurements were performed during peak hours it was assumed that the initial and final air nicotine concentrations in the establishments were the same (c = 0) and thereby the latter term in formula (1) disappears. The formula assumes complete mixing and that adsorption equals desorption at surfaces and, therefore, the calculated average concentration is only suggestive. The theoretical average nicotine concentrations were calculated to evaluate the placement of air sampling locations and to evaluate the quality of the ventilation measurements. SAS-software version 8.2 was used for statistical analyses.
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RESULTS AND DISCUSSION |
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TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTS AND DISCUSSIONCONCLUSIONSACKNOWLEDGEMENTSREFERENCES |
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Twenty establishments were evaluated during the first survey period before the Act and 17–18 establishments after the enforcement of the Act (Table 1). Of these establishments, 14 were the same during all measurement periods (Table 2). All establishments participating in the survey had mixed ventilation, i.e. dilution ventilation and none had displacement ventilation. Displacement ventilation is an air distribution system in which incoming air originates at floor level and rises to exhaust outlets at the ceiling as opposed to mixed ventilation where inlets and outlets may be placed side by side and the contaminants in the air are first diluted by the incoming fresh air before removal through the exhaust outlets. The air change rate in the study establishments varied between 3.3 and 15.3 times per hour (Table 2). Smoking was allowed in all establishments during all the study periods and all establishments had reserved smoke-free areas that were approximately equal to the minimum area allowed by the Finnish Tobacco Act. Nightclubs E and F had in 2004 only reserved the areas around the bar counters as the smoke-free area and it was difficult to judge whether the areas counted for 50% of the service area. The service-area of establishment Q was <100 m2 (80 m2), but they had, nonetheless, reserved 30% of the service-area for non-smoking customers in the year 2000.
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As expected, establishments focused on serving food (dining) showed lower geometric mean (GM) air nicotine and 3-EP concentrations than bars and taverns (pubs) or nightclubs and discos (nightclubs). No significant difference in the aforementioned concentrations can be seen between establishments of the type pubs and nightclubs. The amount of ETS, found at the different types of establishments, followed the same pattern for measurements performed before and after the introduction of the Act. The GM nicotine and 3-EP concentrations at bar counters did not differ from the measured GM concentrations in other parts of the establishments. This was true even though smoking was prohibited at bar counters during the measurements performed after the modified Act had been introduced. In the smoke-free sections, the GM nicotine and 3-EP concentrations were lower than in the smoking sections. Smoke-free sections were not present before the introduction of the Act (Table 1).
Combining all measurements in all types of establishments the measured GM nicotine and 3-EP concentration did not differ statistically between the different study periods. This result is not surprising, as there are no studies reporting drastic changes in the smoking habits in Finland during the time period of this study (Table 3). In Table 3, the statistical analysis used was the Friedman's two-way analysis of variance for the difference between the four measurement periods. Furthermore, to make sure the differences seen are not just due to a change in customer number or smoking frequency during the measurements adjusted values for nicotine and 3-EP were also used in the analysis. The measurement performed before the Act was in force (year 1999) showed a significant difference (P < 0.05) for the measured nicotine concentration adjusted by the number of smoked cigarettes in the arithmetic average of all measurement points in an establishment and at the bar counters when compared with the same measurements performed in 2002 after the Act was in force. Because the same statistically significant difference was not seen for the unadjusted nicotine concentration and the nicotine concentration adjusted by the customer number and because no statistically significant difference was found when 3-EP was used as the ETS marker, it may be concluded that no significant change in ETS-concentration took place after the Act was enforced at bar counters or in the overall ETS-concentration calculated from all measurement points. This difference found in the statistical analysis between the results for nicotine and 3-EP as a marker for ETS may be due to the smaller absolute concentration value of 3-EP compared with nicotine (nicotine 4–5 * 3-EP). When comparing the nicotine and 3-EP concentrations in the smoke-free sections with the arithmetic mean of all measurement points from the measurement period before the Act was introduced, the difference is statistically significant using both unadjusted and adjusted values for nicotine and 3-EP concentrations (Table 3, P 
0.004). This result indicates that customers visiting the smoke-free areas of these restaurants and bars are less exposed to ETS than before the Tobacco Act was in force, but when viewing the measured GM concentrations of nicotine and 3-EP in the smoke-free sections (Table 1) it is clear that exposure to ETS cannot be avoided in the establishments studied, perhaps with the exception of dining restaurants (Table 2). Furthermore, in five establishments the measured nicotine and 3-EP concentrations in the smoke-free section were higher than in the smoking section during the measurements in year 2000 (E, F, G, I and Q in Table 2). All except establishment E and J were able to keep the ETS concentrations in the smoke-free sections below that in the smoking sections during the measurement periods in the years 2002 and 2004.
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Structural changes or changes to the ventilation systems had been carried out in nine of the establishments (A, C, D, E, G, H, J, N and Q). The changes made were mainly changes in the distribution of air, i.e. changes in the amount of air entering bar counters and into smoke-free areas. The changes were not successful in preventing ETS from entering these areas (Table 2).
The Pearson correlation coefficient between all measured air nicotine and 3-EP-concentrations was 0.82 (P < 0.0001) and the Pearson correlation coefficient between the measured and the calculated theoretical nicotine concentration was 0.55 (P < 0.0001). The correlation coefficient for nicotine and 3-EP support the fact that either one or both may be used as ETS markers. The correlation coefficient between the measured average nicotine concentration and the calculated nicotine concentration show that it is possible to estimate nicotine concentration in an establishment by counting smoked cigarettes, using the nicotine emission rate from the literature and measuring the air exchange rate. This calculated nicotine concentration may not be as exact as the measured, but on the other hand, the selection of sampling locations and the number of samples taken greatly affects any calculations on, e.g. average nicotine concentrations in an establishment (Fig. 1). The GM concentrations of the calculated theoretical nicotine concentrations were in 1999, 17.3 µg m–3, in 2000, 17.8 µg m–3, in 2002, 19.9 µg m–3 and in 2004, 18.3 µg m–3, which may be compared to the results presented in Table 1. The calculated theoretical nicotine concentrations indicate that the selection of sampling locations, collection of cigarette butts and measurements of ventilation rates were reasonably successful. The discrepancy between the calculated and measured average nicotine concentration in establishments E, H and J was probably caused by too few samples for this size of establishments (five measurement locations in 484–550 m2) and the discrepancy in establishments L, OP and T was due to too few sampling points in the smoking sections. Nevertheless, these results suggest that by estimating the number of smoked cigarettes, and if the air-exchange rate in an establishment is known, a reasonable estimate of the amount of ETS present can be calculated.
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The Pearson correlation coefficient was 0.7 (P < 0.0001) between the measured TVOC concentration and the measured nicotine or 3-EP concentration. TVOC values may be used as an indicator for indoor air quality, but TVOC is not always a suitable marker for ETS (Fig. 1). Figure 1 presents on a logarithmic scale the relationship between the measured ETS-markers and TVOC and fresh airflow rate expressed in dm3 s–1 per smoked cigarettes in the smoke-free sections of the establishments of this study. Throughout the text dm3 denotes litres. The figure may be used to give an idea of the ventilation rate, which would be needed to gain a reasonable ETS-marker concentration in the smoke-free area, e.g. a nicotine concentration in the smoke-free area of 0.5 µg m–3 may be obtained with a fresh airflow rate of
50 dm3 s–1 per smoked cigarette. Such flow rates are not feasible in restaurants or bars. The ventilation was probably not planned in an optimal way in the study establishments, and, as seen from the coefficient of determination for nicotine R2 = 0.38, there is a lot of uncertainty in the calculations from these real world measurements. Nonetheless, the fresh airflow rates needed to prevent ETS from entering the smoke-free sections are going to be very high in this type of settings where 50% of the service area in a restaurant or bar is to be made smoke-free. Generally, these results suggest that partial smoking restrictions reduce ETS concentrations in smoke-free areas but they far from eliminate workers exposure to ETS. In restaurants serving food partial smoking restrictions seem to work, provided the ventilation system meets the minimum requirements of the Finnish building code (10 dm3 s–1 per person) effective during the measurement periods. The ventilation rates were, in all but two establishments, below the target value, average 6.5 dm3 s–1 per person or m2. Smoking in bars and nightclubs is intense, as proven by the fact that the ETS concentration was nearly 10 times higher in these establishments than in food restaurants. Clearly, a simple separation of smokers from non-smokers is not enough when assigning smoke-free sections in bars and nightclubs. If the smoke-free area is selected without paying attention to the air distribution system, it may cause the ETS concentration to be even higher in the smoke-free area than in the smoking section.
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CONCLUSIONS |
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TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTS AND DISCUSSIONCONCLUSIONSACKNOWLEDGEMENTSREFERENCES |
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In conclusion, the difference in the ETS concentration in smoking and smoke-free sections was small and at bar counters the ETS concentration was similar to the average concentration in the establishments. The requirement set by the amended Tobacco Act in Finland that tobacco smoke has to be prevented from spreading to smoke-free sections was not met in any of the investigated establishments. Neither could a reduction in the ETS concentration at bar counters be observed. It follows that the exposure of workers as well as the public to ETS in the studied establishments had not been reduced as intended by the Finnish legislative body. The selection process for the study establishments left out suburban restaurants and bars, and because only establishments with a serving area larger than 100 m2 were chosen many small pubs were also left out. These aforementioned types of establishments are typically regarded as very smoky environments. In addition, there are many lunch restaurants in workplaces in Finland where smoking has been prohibited since the last modification of the Tobacco Act in 1995 and even before that time. Even though, the authors believe that the effects of the modified Tobacco Act on the ETS-levels in Finnish restaurants and bars presented in this paper can be generalized to the situation in Finland.
To improve working conditions, spreading of ETS to smoke-free sections should be prevented and the working areas (bar counters etc.) should be placed in the smoke-free section. The present study and other studies (Brauer and ‘t Mannetje, 1998; Moschandreas and Vuilleumier, 1999; Spengler, 1999; Maskarinec et al., 2000; Repace, 2000; Jenkins et al., 2001; Cenko et al., 2004) indicate that mixed ventilation without physical barriers will not yield truly smoke-free sections. Other possible solutions to reduce ETS exposure of hospitality workers and patrons include total smoking ban, physical barriers between sections combined with a sufficient airflow from smoke-free to smoking sections, local ventilation solutions at workstations combined with sufficient areal smoking restrictions (Hyvärinen et al., 1997; Yamato et al., 2004; Jacobs and Gids, 2005). Such solutions are not yet common in Finnish restaurants and bars and are, therefore, the subject of forthcoming studies.
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ACKNOWLEDGEMENTS |
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TOPABSTRACTINTRODUCTIONMATERIALS AND METHODSRESULTS AND DISCUSSIONCONCLUSIONSACKNOWLEDGEMENTSREFERENCES |
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The authors wish to thank Mr Markku Raivio, Mr Timo Mielo, Mr Timo Laaja, Mr Jori Reijula, Mr Juha Karhu and Mr Pasi Hynynen for their invaluable work in the field and Ms Hanna Hovi for duly handling the sample stream. The authors are grateful to the Finnish Ministry of Social Affairs and Health for funding this study.
Received October 13, 2005; in final form October 14, 2005
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