COM 0942.115 2006-2008 - Laserfiche WebLink

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FACT SHEET: Outdoor Air PoUndon From Secondhand Smoke James L. Repace Visiting Assistant Professor, Tufts University School of Medicine and Repace Associates, Inc. 101 Felicia Lane, Bowie, MD 20720 U.S.A. <www.renaee.com> 1. Tobacco smoke contains at least 172 toxic substances, including 3 regulated outdoor air pollutants, 33 Hazardous Air Pollutants, 47 Chemicals restricted as Hazardous Waste and 67 Known Human or Animal Carcinogens (Repace, 2006). This is true whether tobacco smoke is inhaled in the act of smoking, or inhaled by nonsmokers out of the air indoors or outdoors. 2. The concentration of tobacco smoke pollution of buildings [secondhand smoke (SHS)] is governed by the density of smokers and by the ventilation rate. Tobacco smoke pollution outdoors or outdoor tobacco smoke (OTS) is determined by the density of smokers, the wind velocity (direction and speed), and the stablity of the atmosphere. 3. SHS concentrations persist for hours after smoking ceases indoors, while OTS concentrations dissipate rapidly after smoking stops outdoors. However, during smoking, OTS levels outdoors may be as high as SHS indoors. 4. A limited number of controlled experiments and field studies of OTS have been conducted in California, Europe, in the Caribbean, and in Maryland: • California (1). The California Air Resources Board study (CARB, 2006), measured OTS nicotine concentrations outside an airport, college, government center, office complex, and amusement park. CARB found that at these typical outdoor locations, Californians may be exposed to OTS levels as high as indoor SHS concentrations. CARB found that OTS was strongly affected by counts of the number of smokers and moderately affected by the size of the smoking area and the measured wind speed. The CARB study indicated that OTS concentrations are detectable and sometimes comparable to indoor concentrations, and demonstrates that the number of cigarettes being smoked (i.e., total source strength), the position of smokers relative to the receptor, and atmospheric conditions can lead to substantial variation in average exposures. CARB declared that OTS is a "toxic air contaminant." • California (2). Klepeis, et al. (2007) measured OTS respirable particle concentrations in outdoor patios, on airport and city sidewalks, and in parks. They also conducted controlled experiments of SHS indoors and OTS outdoors. Klepeis et al. (2007) found that mean SHS particle concentrations outdoors can be comparable to SHS indoors. Within about 2 feet of a smoker OTS was quite high and comparable to SHS concentrations measured indoors. They found that levels measured in 2 sidewalk caf6s were detectable at distances beyond 13 feet. They found that in contrast to SHS, OTS does not accumulate and that OTS peaks are more sensitive to source-receptor proximity and wind velocity. Thus, long-term averages for OTS concentrations are averaged over a large number of transient