Determination of Personal Exposure to Environmental Tobacco Smoke: The “16-Cities Study”

1. Determination of Personal Exposure to Environmental Tobacco Smoke:The “16-Cities Study” Roger A. Jenkins, Andi Palausky, Richard W. Counts, Michael R. Guerin, Amy B. Dindal, and Charles K. Bayne Chemical and Analytical Sciences Division Computer Sciences and Mathematics Division Oak Ridge National Laboratory Presented at the Society for Risk Analysis (SRA) Annual Symposium on Health Risk Assessment Monterey, California October 8, 1997

2. Acknowledgment Research sponsored by the Center for Indoor Air Research under contract No. ERD-88-812 with the Oak Ridge National Laboratory, managed by Lockheed Martin Energy Research Corp. for the US. Department of Energy, under contract DE-AC-05-84OR9622464. Special contributions: Mike Ogden Dave Heavner Katherine Maiolo Sheila Cash Riley Davis Shirley York Teresa Smith Bellomy Research, Inc. R.J. Reynolds Tobacco Co.

3. Study Objective and Design:Determination of Personal Exposure to ETS • Focus on subjects in urban areas. • 100 non-smokers from each area. • Each subject wears a sampling pump at their workplace (8 hours) and “away from work” (16 hours). • Away-from-work includes commuting, shopping, dining, home, and sleeping. • Particle and gas phase ETS components collected. • Smoking status assessed using salivary cotinine.

4. 16 Urban Areas Distributed Geographically Seattle Portland Buffalo Boise Grand Rapids Philadelphia Indianapolis Baltimore Columbus St. Louis Fresno Knoxville Phoenix San Antonio Daytona Beach New Orleans

5. Constituents DeterminedORNL 16 Cities Exposure Study • ETS Particle Phase • Respirable suspended particulate matter (RSP) • UV-absorbing particulate matter (UVPM) • Fluorescing particulate matter (FPM) • Solanesol • Scopoletin • ETS Vapor Phase • 3-ethenyl pyridine • Nicotine • Myosmine • Saliva • Cotinine

6. Participant Inclusion Criteria • Older than 18 years of age • No tobacco use within the last 6 months (includes prescription use of patch or gum) • Work at least 35 hours per week outside the home or a regular shift. • Avoid selected professions to exclude overly inquisitive participants or those with an interest in the outcome. • No membership in smoking related public interest groups. (Either side of the issue.)

7. Subject Information Database • Demographic • Age, sex, household income, smoking history, household size, number of smokers • Lifestyle • Exercise frequency, size and location of home and workplace, heating and cooling system, pets, dietary habits. • Self-Reported Exposure Information • Number of cigarettes, cigars, pipes being smoked; incensed burned, food cooking smells, wood burning fireplaces. • Weather during exposure study • Temperature, relative humidity, cloud cover, precipitation.

8. Study Design: 2 x 2 Cell Structure

9. Subjects are Re-Screened When They Arrive at the Test Center

10. Acquisition of Saliva Samples Subject chews cotton dental dam for 60 seconds

11. Sampling Pump Pump Unit Sound-proofing

12. Sampler Head Particulate Filter Cyclone Separator XAD-4 Cartridge for ETS vapors

13. Subject Sample Acquisition Schedule • 8:45 pm Day 1: Saliva • 8 am - 5 pm Day 2: Workplace ETS air Sample • 5 pm Day 2 - 8 am Day 3: Away-from-Work ETS air sample • 4 pm - 7pm Day 3: Saliva

14. Sample Collection in the Workplace Sampling Head Sampling Pump

15. Subject Demographics: Gender

16. Study Demographics: Age

17. Study Demographics: Household Income

18. Subject Demographics: Race Whites slightly over- represented at expense of other minorities

19. Study Demographics: Education

20. Study Demographics: Occupational Category

21. Limits of Detection

22. Salivary Cotinine Definitions Start: Mean of duplicate analysis of Day 1 saliva samples End: Mean of duplicate analysis of Day 3 saliva samples “Average”: Mean of Start and End values

23. Distribution of Average Cotinine Values Actual value: 1114 Subjects Actual value: 132 subjects

24. “Misclassification” Rates of Subjects Claiming to be Non-SmokersAll Subjects Recruited on Basis of Non-Smoking Status

25. Estimated Misclassification Rates of Subjects Claiming to be Never-SmokersAll Subjects Recruited on Basis of Non-Smoking Status

26. Distribution of 24-hour TWA RSPLevelsSubject Segregation by Self-Reported Home and Workplace Smoking Status Confirmed by Diary Observations(All Subjects with Avg. Cotinine <15 ng/mL)

27. Distribution of 24-hour TWA Nicotine LevelsSubject Segregation by Self-Reported Home and Workplace Smoking Status Confirmed by Diary Observations(All Subjects with Avg. Cotinine <15 ng/mL)

28. Concentrations of Selected ETS Markers:Confirmed Smoking/Non-Smoking LocationsMedian 24-hr TWA Levels, ug/m3

29. Concentrations of Selected ETS Markers:Confirmed Smoking/Non-Smoking Locations95th Percentile 24-hr TWA Levels, ug/m3

30. Concentrations of Selected ETS Markers:Confirmed Smoking/Non-Smoking LocationsMedian 24-hr TWA Levels, ug/m3Gender Related Differences? * Estimated

31. Concentrations of Selected ETS Markers:Confirmed Smoking/Non-Smoking LocationsMedian16-hr Away-from-Work Levels, ug/m3Males who Work in Smoking Environments are Exposed to Higher Levels of ETS Away-from-Work

32. ETS Exposures of Subjects in Confirmed Smoking Environments Exposure: Concentration x Time, in ug-hr/m3

33. Median ETS Exposures* in Environments Where Smoking is UnrestrictedExposure = Concentration x Time * Smoking confirmed by diary reports

34. Exposures in Unrestricted Smoking Environments*Exposures in ug-hr/m3 * Smoking confirmed by diary reports

35. Salivary Cotinine DistributionsSubject Cells Confirmed through Diary Observations Cell 1 Cell 3 Cell 2 Cell 4

36. Comparison of Salivary Cotinine Levels and Nicotine ExposureCell Classification by Screening Questionnaire and Diary Observations

37. Avg. Salivary Cotinine Levelas a Function of Nicotine ExposureAll Subjects with Both Markers >95% CL above LODNicotine: 0.063 ug/m3; Cotinine: 1.01 ng/mL • R2 = 0.105

38. Correlation of Individual Salivary Cotinine Levels and Nicotine Exposures263 Subjects with 24-hr TWA Nicotine and Avg. Cotinine > 95% C.L. above LODs

39. Implications for Risk Assessment: Never Smoking Female Misclassification Rates

40. How “Never-Smoker” Misclassification Rates Impact EPA’s Relative Risk Estimation 16 Cities Females Cutoff: 100 ng/mL EPA’s Point Estimate 16 cities Females Cutoff: 30 ng/mL

41. Observations and ConclusionsBased on Study Design and Subject Population • Subjects who live and work in smoking environments are exposed to 30 - 60 times more ETS than subjects living and working in non-smoking environments. • ETS levels are lower than those predicted from shorter duration or area measurements. • ETS levels determined away-from-work (smoking homes) are comparable to slightly lower than those determined for previously reported residential studies. • The home appears to be a more important source than the workplace for ETS exposure, due to time spent in the environment.

42. Observations and Conclusions(continued)Based on Study Design and Subject Population • Gross subject smoking status misclassification ranges from 2.2% to 6.6%, depending on subject sex and cut-off level. • Median average salivary cotinine level is proportional to median nicotine 24-hr TWA level on a cell by cell basis (100+ subjects per cell). (R2 = 0.991) • Median average salivary cotinine level is NOT predictive of 24-hr TWA nicotine level on an individual subject basis (R2 = 0.105) at levels of ETS exposure encountered under the protocol used for this study.