oa Secondhand Smoke Emission levels in Waterpipe Cafes in Doha, Qatar

Background

Morbidity and premature mortality associated with exposure to secondhand tobacco smoke (SHS) represent a major global public health burden, and SHS exposure arising from all sources is responsible for an estimated 600 000 premature deaths. 1 The adverse health effects associated with waterpipe (WP) SHS exposure have been less well investigated compared with cigarette SHS. 2 Nonetheless, evidence shows that WP SHS contains similar tobacco-related toxicants as cigarette SHS, including more than 60 carcinogens, and fine respirable suspended particles, which can be deposited deep into the lung. Article 8 of the WHO's Framework Convention on Tobacco Control (FCTC) requires party nations, in part, to adopt, implement and actively promote effective legislative or other measures to protect the public from exposure to secondhand smoke in indoor workplaces and public places. In 2002, Qatar adopted smoke-free legislation that prohibits cigarette smoking inside public venues. 12 Although fines ranging between QAR200 and QAR500 (approximately US$55–US$137) may be imposed, the clean indoor air law is seldom enforced in Qatar. Tobacco WP use has recently experienced a marked increase in popularity in Middle Eastern and South Asian countries, where it has been a traditional form of tobacco use since at least the mid-17th century. 15 The tobacco WP, also often referred to as ‘shisha’ in Qatar and many Middle Eastern countries and ‘hookah’ in western countries, heats highly flavoured, moist mo'assel tobacco. One factor that may contribute to the popularity of WP use is the perception of lowered risk of WP smoking, compared with cigarette smoking. Objective data on indoor air quality in public venues in Qatar have not previously been reported. Air quality measurements in public venues have now been conducted among a substantial number of jurisdictions internationally to help promote smoke-free policy development and assess legislative compliance. 28 The purpose of this investigation was to measure respirable suspended particulate matter of 2.5 μ or less (PM2.5), a marker for SHS, in WP cafes in Qatar's largest city, Doha. The small size of PM2.5 emissions, which arise from combusted tobacco, allow them to be easily inhaled and deposited deep within the lungs, contributing to serious respiratory and cardiovascular diseases. Methods Particulate matter (PM2.5) levels were measured inside and outside of a sample of 40 waterpipe cafes and 16 smoke-free venues in Doha, Qatar between July and October 2012. In addition, the number of waterpipes being smoked and the number of cigarette smokers were counted within each venue. Non-paired and paired sample t tests were used to assess differences in mean PM2.5 measurements between venue type (waterpipe vs smoke-free) and environment (indoor vs outdoor).

Results

The air quality in 40 WP cafes (smoking venues) was measured for a mean duration of 35.6 min (SD = 3.7). The mean internal volume of smoking venues (365.8 m³, range = 85–1449) tended to be smaller than that of non-smoking venues (682.1 m³, range = 34–3120), although the difference was not statistically significant (t(52) ≤ 1.0, p = 0.90). The smoke-free venues were monitored for a mean duration of 35.4 min (SD = 8.5). Active smoking of WPs and cigarettes was observed in all 40 smoking venues with more WP smoking being observed. The mean number of WPs observed in active use was 9.4 (range = 0.7–27.3), while the mean number of cigarette smokers observed was 1.5 (range = 0.3–4.6). The mean WP ASD (mean = 0.035 smokers/m³; SD = 0.027) was significantly greater than the cigarette ASD (mean = 0.006 smokers/m³; D = 0.005: t(39) = 16.0, p < 0.001). No active smoking (WP or cigarette) was observed inside the smoke-free venues. The mean PM2.5 level inside the 40 WP cafes (mean = 476.1 μg/m³; SD = 309.6) was significantly higher than the mean PM2.5 level found immediately outside these venues (mean = 34.5 μg/m³, SD = 11.6; t(39) = 25.7, p < 0.001). PM2.5 levels inside the smoking venues also were significantly higher than inside the smoke-free venues (mean = 16.8 μg/m³, SD = 12.1; t(54) = 16.9, p < 0.001). Mean PM2.5 levels outside the smoke-free venues (mean = 30.3 μg/m³, SD = 33.4) were significantly higher than the levels observed inside those venues (t(15) = 3.4, p = 0.003). The proportion of active WP smokers, as a per cent of total smokers WP + cigarette), ranged from 58? to 97?. There was a significant positive correlation between PM2.5 levels and WP ASD (r = 0.38, p = 0.015), but not with cigarette ASD (r = 0.20, p = 0.223). ASD for the non-smoking venues was 0.

Conclusions

The mean levels of fine particulate pollution observed among a sample of WP cafes in Doha, Qatar were found to be significantly higher compared with smoke-free venues. Particulate levels were also more than 13-fold greater inside WP cafes, compared with outside these venues. To contextualise the observed PM2.5 levels, the WHO has set an air quality guideline for 24 h exposure of 25 μg/m³. 32 While patrons and staff are not likely to experience 24 h exposure, exposure to the levels observed here for just a few hours a day is likely to comprise a serious health risk in the longer term. These data reveal that the exemption for WP cafes in Qatar's smoke-free legislation has resulted in environments that are unsafe for workers and the public. As such, further actions and amendments for the law are needed. In 2013, after the completion of data collection for the present study, the Qatari Supreme Council of Health started working on introducing amendments to the smoke-free law of 2002. The amended smoke-free law is intended to provide more comprehensive protections and will prohibit all types of indoor smoking in public places, including WPs, and increase fines for non-compliance. Further, Qatar has succeeded in banning tobacco advertisements and promotions. These actions provide an excellent opportunity to ensure that implementation and enforcement of the new law is performed optimally. Future research should investigate the short-term impact of banning WP smoking on air quality and SHS exposure, and, in the longer term, the potential for changes in social norms and the relationship to the prevalence of use and health outcomes. The current investigation adds to the growing literature on the contributions of WP SHS on indoor air quality. Qatar has demonstrated its intent to protect the public from the dangers of SHS by enacting its smoke-free legislation, and by ratifying the FCTC. However, SHS remains a major contributor to elevated levels of PM2.5 in WP cafes. Comprehensive smoke-free legislation, which applies to all venues and for all combusted tobacco products, is a welcome development in the tobacco control policy of Qatar. If implemented and enforced appropriately, the experience of Qatar may serve as an example to the wider EMR. These data provide further evidence for policymakers that indoor WP use threatens to undermine the potential benefits of tobacco control policies in the Middle Eastern region and other countries in which WP use is a popular practice. Comprehensive indoor smoking bans, which do not exclude WP use, are needed to address a significant flaw in the smoke-free laws of some jurisdictions.