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Comparing Methods for the Real- Time Measurement of Secondhand Tobacco Smoke Particles Neil E. Klepeis Visiting Scholar, Stanford University, Department.

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Presentation on theme: "Comparing Methods for the Real- Time Measurement of Secondhand Tobacco Smoke Particles Neil E. Klepeis Visiting Scholar, Stanford University, Department."— Presentation transcript:

1 Comparing Methods for the Real- Time Measurement of Secondhand Tobacco Smoke Particles Neil E. Klepeis Visiting Scholar, Stanford University, Department of Statistics http://Klepeis.Nethttp://ExposureScience.Orgneil@klepeis.net

2 Background Issues: Real-Time Particle Instruments n Can these instruments be used to characterize secondhand smoke? n Are they sensitive? n Are they convertible to standard measures? n Are they reliable and consistent?

3 Addressing the Issues n Field Studies of Secondhand Smoke Exposures n Controlled Studies of Exposure Factors n Controlled QA Studies Systematically Comparing and Evaluating Instruments

4 The Instruments

5 Real-Time Particle Monitoring Instruments, Part I A. Nephelometer (Radiance) B. Piezobalance (TSI/Kanomax) C. PAH (Ecochem) D. Laser Counter (GRIMM) E. CO (Langan)

6 Real-Time Particle Monitoring Instruments, Part II A. Laser Counter (Met-One) B. SidePak (TSI) C. PC/DC (Ecochem & Siegmann) D. Ultrafine 3007 CPC (TSI)

7 Reference Measure: Piezobalance Versus Filter Mass for Cigarettes and Incense

8 Evolution of the Secondhand Smoke Aerosol Size Distribution

9 Field Exposure Studies

10 Outdoor Restaurants and Pubs with Smokers

11 A Cigar

12 Outdoor Hookah Restaurant

13 Blowing Hookah Smoke Into Monitors Cigarette Smoke

14 Controlled Exposure Studies

15 Outdoor Proximity Experiments

16 Indoor-Outdoor Comparison

17 3D Monitoring Array to Study Outdoor Proximity and Wind Effects

18 Automobile Monitoring

19 QA Studies

20 Consistency and Correspondence n Do different monitors of the same type match each other? n Does the same monitor react the same on different days when using the same source and the same or different environmental conditions? n Can readings from one type of monitor be used to predict those of another? n Is the relationship between monitors of different types the same under different conditions, time scales, etc?

21 Four Suites of Side-by-Side QA Experiments (1). 31 Cigarette & Incense Experiments: Commercial Location; Grimm, Ecochem, Filters, Piezobalance (2). 7 Cigarette Experiments: Residential 44 m 3 Bedroom; MIE DataRam, Ecochem, Piezobalance, Humidity, Temperature (3). 5 Cigarette Experiments: Residential 44 m 3 Bedroom; Grimm, Ecochem, Piezobalance, Nephelometers. (4). 15 Cigarette Experiments: Residential 44 m 3 Bedroom; Grimm, Ecochem, PC/DC, Piezobalance, Nephelometers, SidePak, Humidity, Temperature

22 Suite 4 Bedroom Experiments

23 Are Two Instruments of the Same Type Consistent?

24 Two Matched Piezobalances

25 Consistency Between Two Light Scattering Instruments

26 Are Measurements Consistent Across Experiments on Different Days?

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31 Can Measurements be Reliably Converted to Respirable Particle Mass (Piezobalance)?

32 SidePak Factory Calibration Certificate

33 Piezobalances and SidePak (Factory-Calibrated) Elapsed Minutes

34 Piezobalance Versus SidePak Regression

35 Piezobalance and SidePak (Custom-Calibrated)

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37 Non-Linear Effects

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40 Summary and Conclusions

41 Summary and Conclusions: Instrument Evaluation n Real-time instrument measurements can be related to standard methods and are generally sensitive, consistent, dependable, and quantitative indicators of tobacco smoke concentrations. n Matched instruments are very comparable, e.g., for use in studies of relative exposures n Factory calibrations of aerosol monitors cannot be assumed to be reliable for application to SHS n Two instruments analyzing different aerosol components and sizes may have a nonlinear relationship when including both fresh and aged aerosol n Light scattering instruments have a linear relationship to respirable mass, with an associated conversion factor n Instrument responses and relationships vary by composition and size of particle emissions n Relative humidity appears to have a small effect (50 to 75%)

42 Future Work on Real-Time Particle Monitoring n Formalize Central Tendency and Variability in Instrument Interconversion Factors n More Side-by-Side Comparison of Instrument Responses in the Field n Consider Mixture of Cigarette Types n Use Real Smokers

43 Upcoming Report on Instrument Evaluation n Detailed description of all experiments n Results of all instrument comparisons n Best estimates of instrument conversion factors n Contact: neil@klepeis.net n Web: http://ExposureScience.Org

44 Last Words n Real Time Methods Allow us to Identify the Impact of Specific Minute-by- Minute Changes in Environmental Conditions and Human Behavior on Exposure n Unique Tool to Judge the Effectiveness of Exposure Reduction Measures n Immediate and Dramatic Feedback for Interventions n Development of Educational Materials

45 Acknowledgements n Wayne Ott, Stanford University n James Repace, Repace Associates n Paul Switzer, Stanford University n Lynn Hildemann, Stanford University n California Proposition 99, UCSF n Tobacco-Related Disease Research Program of California (TRDRP) n Flight Attendant Medical Research Institute (FAMRI) in Miami, FL n U.S. Environmental Protection Agency


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