1. Monitoring Airborne Levels of Outdoor and In-Vehicle Secondhand Tobacco Smoke Neil E. Klepeis, Ph.D. Human Exposure Research Associate Stanford University, Stanford, CA http://klepeis.net, http://exposurescience.org

2. Why Monitor Secondhand Smoke? Judge severity of exposure Communicate risks Encourage smoking restrictions and bans Identify exposure reduction measures Establish disease association (epidemiology)

3. Why Monitor Outdoors and in Cars? Last frontiers for smoking bans Very few studies available How high can outdoor levels really be? Practical Questions What if I open my car window or use the ventilation during smoking? What if I smoke near my child outdoors?

4. Environmental Health Cycle

5. Direct Link to Tobacco Control

6. What's in this Talk? Introduce Air Monitoring Instruments New Outdoor SHS Surveys and Experiments New In-Vehicle SHS Experiments Predictive Modeling of SHS Exposure and Risk

7. Portable Airborne Particle Monitoring Instruments A. Laser Counter; B. SidePak Laser Photometer; C PC/DC Monitor; D. Condensation Nucleii Counter A. Nephelometer; B. Piezobalance; C PAH Analyzer; D. Laser Particle Counter; E. CO Sensor

8. Outdoor Secondhand Smoke Monitoring in Sidewalks Cafes, Parks, Pubs, Restaurants

9. Visits to Sidewalk Cafes & Restaurants 10 Locations 2000 minutes of continuous measurements Natural Human Smokers Controlled Smoking

10. Experiments with a Real Smoker SidePak Monitor Air Speed Monitor

11. Elevated Levels Near the Smoker 0.5 m 252 g/m 3 0.5 m 233 g/m 3 0.5 m 222 g/m 3 0.8 m 127 g/m 3 2.0 m 41 g/m 3 2.0 m 14 g/m 3 3.7 m 14 g/m 3 3.7 m 5 g/m 3

12. Burning Cigarette Experiments

13. Elevated Downwind Levels from a Smoker 0.3 m 582 g/m 3 0.6 m 130 g/m 3 0.9 m 127 g/m 3 0.6 m 2 g/m 3 1.2 m 41 g/m 3 2.7 m 13 g/m 3

14. Controlled Patio Experiments Air Monitor Assemblies on Either Side of a Burning Cigarette

15. The Proximity Effect

16. Summary of Outdoor Results Being downwind from a smoker is the critical factor Levels drop off dramatically beyond 2 meters from a smoker – although levels can still be detected as far away as 9 meters or more. Being close to and downwind from an active smoker can lead to very high transient levels Short-term outdoor levels can exceed secondhand smoke levels measured inside smoking cars and houses

17. In-Vehicle Secondhand Smoke Monitoring in Passenger Cars and SUV's

18. Vehicle Air Exchange Rates 85 Air Changes Five Vehicles Tracer Gas Releases Five Driving Speeds Window Positions Ventilation Settings

19. Air Exchange as a Function of Car Speed

20. Experiments In Cars with Smokers 3 Rented Vehicles 2 Smokers 14 Cigarettes Particle/CO monitoring Five Speeds Window Positions Ventilation Settings

21. Levels Inside a Car with a Smoker A. Ford Taurus, 20 mph B. Ford Taurus, 60 mph A B

22. Predicting In-Vehicle Levels Levels are well predicted using a mathematical mass balance model.

23. Simulation of Levels in a Car Rapid Feedback and Flexible Educational Tool

24. Summary of In-Vehicle Results Opening windows increases the air exchange rate by a factor of 10 Air exchange rate of car increases with speed Smoking in a closed car results in extremely high levels that are about 10 times higher than those measured in smoking homes Short-term levels with windows open or active ventilation can still approach levels found in smoking homes Levels in cars can be characterized using mathematical models

25. Practical Modeling of Daily (24-h) Exposure and Risk: Fine Particles 68 mg/m 3 106 mg/m 3 65 mg/m 3 41 mg/m 3 AmbientOutdoorsCarUSEPA Unhealthy 17 Cigarettes 2 Cigarettes PM-2.5 Sens. People Downwind Closed/Moving Standard

26. Resources ExposureScience.Org Downloadable Reports, Articles, and Software Related to Secondhand Tobacco Smoke Exposure in Cars, Homes, and the OutdoorsSimSmoke.Org On-line Simulation of Secondhand Smoke Exposures in Indoor and Outdoor Settings

27. Acknowledgments Wayne Ott, Stanford University (Co-Investigator) Paul Switzer, Stanford University (Principle Investigator) Grant from the Flight Attendant Medical Research Institute (FAMRI) Grant from California Proposition 99 Past Grant from Tobacco-Related Disease Research Program (TRDRP)