# Presentation: 741683

## 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

## 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*

- R.J. Reynolds Tobacco Co.

- Bellomy Research, Inc.

## 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.

## 16 Urban Areas Distributed Geographically

*Seattle*

*Boise*

*Fresno*

*Phoenix*

*San Antonio*

*New Orleans*

*Daytona Beach*

*Knoxville*

*St. Louis*

*Baltimore*

*Philadelphia*

*Portland*

*Buffalo*

*Columbus*

*Indianapolis*

*Grand Rapids*

## Constituents DeterminedORNL 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*

## 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.)

## 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.

## Study Design:  2 x 2 Cell Structure

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

## Acquisition of Saliva Samples

***Subject chews cotton dental***
***dam for 60 seconds***

## Sampling Pump

***Pump Unit***

***Sound-proofing***

## Sampler Head

***Particulate Filter***

***Cyclone Separator***

***XAD-4 Cartridge for***
***ETS vapors***

## 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

## Sample Collection in the Workplace

**Sampling Pump**

**Sampling Head**

## Subject Demographics:  Gender

## Study Demographics:  Age

## Study Demographics:  Household Income

## Subject Demographics:  Race

- Whites slightly over-
- represented at expense
- of other minorities

## Study Demographics:  Education

## Study Demographics:  Occupational Category

## Limits of Detection

## 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

## Distribution of Average Cotinine Values

- Actual value:  1114 Subjects

- Actual value:  132 subjects

## “Misclassification” Rates of Subjects Claiming to be Non-SmokersAll Subjects Recruited on Basis of Non-Smoking Status

## Estimated Misclassification Rates of Subjects Claiming to be Never-SmokersAll Subjects Recruited on Basis of Non-Smoking Status

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

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

## Concentrations of  Selected ETS Markers:Confirmed Smoking/Non-Smoking LocationsMedian 24-hr TWA Levels, ug/m3

## Concentrations of  Selected ETS Markers:Confirmed Smoking/Non-Smoking Locations95th Percentile 24-hr TWA Levels, ug/m3

## Concentrations of  Selected ETS Markers:Confirmed Smoking/Non-Smoking LocationsMedian 24-hr TWA Levels, ug/m3Gender Related Differences?

- * Estimated

## Concentrations of  Selected ETS Markers:Confirmed Smoking/Non-Smoking LocationsMedian 16-hr Away-from-Work Levels, ug/m3Males who Work in Smoking Environments are Exposed to Higher Levels of ETS Away-from-Work

***Concentrations of  Selected ETS Markers:******Confirmed Smoking/Non-Smoking Locations***_***Median***_*** ***_***16-hr Away-from-Work Levels***_***, ug/m******3******Males who Work in Smoking Environments are Exposed to Higher Levels of ETS Away-from-Work***

## ETS Exposures of Subjects in Confirmed Smoking Environments

***Exposure:  Concentration x Time, in ug-hr/m3***

## Median ETS Exposures* in Environments Where Smoking is UnrestrictedExposure = Concentration x Time

**  Smoking confirmed by diary reports*

## Exposures in Unrestricted Smoking Environments*Exposures in ug-hr/m3

**  Smoking confirmed by diary reports*

## Salivary Cotinine DistributionsSubject Cells Confirmed through Diary Observations

**Cell 1**

**Cell 2**

**Cell 3**

**Cell 4**

## Comparison of Salivary Cotinine Levels and Nicotine ExposureCell Classification by Screening Questionnaire and Diary Observations

## Avg. Salivary Cotinine Levelas a Function of Nicotine ExposureAll Subjects with Both Markers >95% CL above LODNicotine:  0.063 ug/m3; Cotinine: 1.01 ng/mL

**R****2**** = 0.105**

## Correlation of Individual Salivary Cotinine Levels and Nicotine Exposures263 Subjects with 24-hr TWA Nicotine and Avg. Cotinine > 95% C.L. above LODs

## Implications for Risk Assessment:  Never Smoking Female Misclassification Rates

## How “Never-Smoker” Misclassification Rates Impact EPA’s Relative Risk Estimation

- EPA’s Point
- Estimate

- 16 Cities Females
- Cutoff:  100 ng/mL

- 16 cities Females
- Cutoff:  30 ng/mL

## Observations and ConclusionsBased 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.

## 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.