Environ. Sci. Technol. 1990, 24 848-852 I
Solanesol: A Tracer for Environmental Tobacco Smoke Particles Hongmao Tang, Galen Richards, Cynthia L. Benner, Jari P. Tuomlnen, Milton L. Lee, Edwin A. Lewis, Lee D. Hansen, and Delbert J. Eatough"
Chemistry Department, Brigham Young University, Provo, Utah 84602
Concern about the health effects of passive smoking and exposure of a large population to environmental tobacco smoke have generated the need for a quantitative tracer of environmental tobacco smoke. Solanesol, a trisesquiterpenoid alcohol, has been shown to be present in environmental tobacco smoke. Results from the determination of particulate-phase solanesol in environmental tobacco smoke in both chamber and indoor environments show that solanesol is a suitable tracer for the particulate phase of environmental tobacco smoke.
Introduction Environmental tobacco smoke (ETS) is an important component of indoor air pollution. Data in the literature indicate that exposure to environmental tobacco smoke leads to an increased incidence of respiratory disease and the impairment of lung development in children, and to the development of lung cancer ( 1 , 2 ) . These health concerns and the exposure of a large population to environmental tobacco smoke have generated the need for a quantitative tracer of ETS. According to a review by the National Academy of Sciences ( I ) , a suitable tracer for quantifying environmental tobacco smoke concentrations should be (1)unique or nearly unique to environmental tobacco smoke, (2) easily detected in air, even at low smoking rates, (3) similar in emission rates for a variety of tobaccos, and (4) in constant proportion to compounds in ETS that have effects on human health. Tracers of environmental tobacco smoke used in the past include respirable (or total) suspended particulate matter (RSP), CO, nitrogen oxides, nicotine, N-nitrosamines, aromatic hydrocarbons, and frequency of smoking. Recent reviews of environmental tobacco smoke by the National Academy of Sciences (1) and the US. Surgeon General (2) reach the same conclusion, i.e., the only tracers previously used that may be related to actual exposure to environmental tobacco smoke are concentrations of nicotine and RSP. As pointed out in these reviews, both of these tracers have potential problems. The use of nicotine as a tracer of environmental tobacco smoke is complicated by the fact that nicotine is found primarily in the gas phase in the environment (3-6). Furthermore, nicotine is strongly basic and is removed from indoor environments at a faster rate than particulate-phase nicotine or the particulate portion of environmental tobacco smoke (1,6-10). Thus, the concentration of gas-phase nicotine may underestimate exposure to the particulate phase of ETS. In addition, the gas-/particulate-phase distribution of nicotine may be altered during sampling. Badre et al. (11) found an 80% loss of added nicotine from filters after sampling for 50 min at 4 standard L/min (sLpm). Similar effects have been noted when sampling for nicotine in environmental tobacco smoke particles on filters (12, 13). The experimentally determined concentration and phase distribution of nicotine may thus be dependent on the sampling system used. Because of the ease with which it may be measured, total RSP has been commonly used as a tracer for environmental tobacco smoke in past studies ( I , 2). However, 848
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several studies (6, 14, 25) have shown that even though RSP is elevated in environments where smoking is present, about half of the RSP in these environments does not come from environmental tobacco smoke. RSP thus overestimates exposure to environmental tobacco smoke. Solanesol, a trisesquiterpenoid alcohol in tobacco leaf,
CH,C(CH3)=CH(CH&H&(CH3)=CH)&HzOH has been shown to be present in tobacco smoke condensate (16,17)and environmental tobacco smoke (18,19). Studies previously reported by Ogden et al. (18,19) suggest that the concentration of solanesol in ETS particles is conserved in the indoor environment. Solanesol is nonvolatile because of the large molecular weight (631) and, hence, is present only in the particulate phase of environmental tobacco smoke (18). In this paper, the potential use of solanesol as a tracer for environmental tobacco smoke is evaluated. The concentrations of solanesol in controlled chamber studies and in indoor environmental tobacco smoke were determined and compared to several other components of ETS.
Methods Sample Collection. Particulate samples for the determination of solanesol in simulated environmental tobacco smoke were obtained from sidestream smoke generated in a collapsable 30-m3Teflon chamber (5, 6). In these experiments, either one-half or four cigarettes (1R1 and 1R4F research cigarettes, University of Kentucky) were smoked in the Teflon chamber using a standard cycle (5). The mainstream portion of the smoke was vented to the outside of the chamber. Samples of the generated particles were passed through a 10-mm Teflon line and collected on quartz filters (2500 QAST, Pallflex Products Corp.) at l-h intervals over a -4-h period after combustion of the cigarette (5). Before use, the filter was washed with 0.1 M HC1 at 60 "C for 12 h, thoroughly rinsed with water, and heated at 600 "C for 12 h. The sample flow rate was set at 30 sLpm (standard liters per minute, 25 "C and 1 atm) by use of a Tylan mass flow controller. In addition to the collection of particles for the determination of solanesol, the CO and total particulate concentrations in the chamber during each of the experiments were determined with a CO detector and a piezobalance, as previously described (4, 5 ) . The concentrations of particulate-phase nicotine and of gas-phase nicotine and 3-ethenylpyridine were determined by sampling with a benzenesulfonic acid coated annular denuder followed by a quartz or Teflon filter to collect particles and a benzenesulfonic acid coated quartz filter to trap any alkaloids lost from the particles during sampling, as previously described (5, 13). Particulate samples for the determination of solanesol were also obtained during a study to compare sampling techniques for nicotine (13). Environmental tobacco smoke in these studies was generated in the chamber facility at the Pierce Laboratory by volunteer smokers. The concentration of tobacco smoke constituents was controlled by the rate of chamber ventilation. Samples for determination of solanesol were collected on 47-mm Teflon
0013-936X/90/0924-0848$02.50/0
0 1990 American Chemical Society
filters. Each filter was contained in a Teflon filter holder (Mace Inc.) and preceded by a cyclone with a 2.5-pm particle cut. Samples were collected at a 5-sLpm flow rate with the flow controlled by a Tylan mass flow controller. Samples for determination of tobacco alkaloids were collected as described above. Solanesol in environmental tobacco smoke in indoor environments was determined by collecting particles on acid-washed, fired quartz filters. The Teflon filter holder (Mace) used in these experiments was preceded by a cyclone with a 2.5-pm particle cut. As in the 30-m3Teflon chamber experiments, the sample flow rate was set at 30 sLpm by using a Tylan mass flow controller. Samples were obtained from two different locations. The first building sampled was a small office building. Samples were collected at three locations in this building. Sampling location A was just outside the open office of a heavy smoker. Sampling location B was in the small lunchroom of the building where smoking occurred during break periods. Sampling location C in the building was in a library remote from any smokers. Samples were collected at these three locations over a 6-h sampling period on two different days. The second building sampled was a crowded disco with several smokers present during the 2-h evening sampling period on two different days. Blank samples were obtained for all of the indoor environmental studies. The concentrations of fine particles (C2.5 pm), CO, gas-phase nicotine and 3-ethenylpyridine,and particulate-phase nicotine were also determined by using sampling systems previously described for the indoor sampling program (6). Analysis of Solanesol Collected on Quartz Filters. In initial experiments, the filters were extracted with methylene chloride for 24 h in a Soxhlet extractor, and the resulting solutions were evaporated to -2 mL in a rotary evaporator. The solutions were then transferred to a vial for analysis. Recovery experiments showed that solanesol was destroyed during the Soxhlet extraction; the recoveries averaged 57 f 7%. Two sequential extractions with CH2C12for 20 min with an ultrasonic bath reduced the loss problem and gave recoveries of 89 f 2%. Extracts were analyzed by gas chromatography (GC) and supercritical fluid chromatography (SFC). Experiments with reagent-grade solanesol (Sigma) showed that direct GC analysis of solanesol was not feasible (19,20) because solanesol degraded to several products at the final GC column temperature of 310 "C. Therefore, the solanesol was derivatized prior to the GC analysis with N,N-bis(trimethylsily1)acetamide (BTSA) in dimethylformamide (DMF) solvent (both from Aldrich Chemical) (20). In this derivatization, the CH2C12was removed from a fraction of the extract by nitrogen, and 200-pL portions each of BTSA and DMF were added. The sample vial was sealed with a Teflon-lined cap and heated in a water bath at 76 "C for 30 min with frequent agitation by hand. Quantitative analyses were performed using a Hewlett-Packard Model 5890 gas chromatograph equipped with a 5-m X 0.5" fused-silica capillary column (2.0-pm df methyl silicone) using the splitless injection mode. The column temperature was held at 210 "C for 4 min and then programmed at 310 "C at 5 "C/min. The column was then held at 310 "C for 10 min. The helium carrier gas flow rate was 15 mL/min, the injector temperature was 300 OC, and the flame ionization detector temperature was 350 "C. Peak areas were measured with an H P Model 3392A integrator. Under those conditions, solanesol eluted 3 min after the column reached 310 OC. The gas chromatograph was calibrated with a solanesol solution of reagent-grade solanesol (Sigma) dissolved in methylene chloride and
Derivatized Solanesol
-
2
, 40 60
110
160
210
TEMPERATURE
260
310
'C
Figure 1. GC chromatogram of a derivatized extract of the collected particles of environmental tobacco smoke. Conditions: see text.
analyzed according to the procedure outlined above. The SFC apparatus (21,22) used in this study was a Lee Scientific Model 501 (Salt Lake City, UT) equipped with a flame ionization detector (FID). Supercritical fluid grade carbon dioxide (Scott Specialty Gases, Plumsteadville, PA) was used as the mobile phase. A 4-m X 50-pm-i.d. capillary column coated with a biphenylcarboxylate ester substituted polysiloxane stationary phase and connected to a frit restrictor was used. This connection was made by using a zero-dead volume butt connector. A Valco C14W highpressure valve (VICI, Houston, TX) with rotor having a sample loop of 200 nL was set up for direct injection. An H P 3392A integrator was used for peak integration. The underivatized extracted sample solution was analyzed directly. The SFC conditions were as follows: injector temperature, 25 "C; FID temperature, 350 "C; oven temperature, 120 "C; density program, from 0.20 (2 min) to 0.45 g mL-' (10 min) at 0.02 g mL-' min-', then to 0.50 g mL-' (1min) at 0.005 g mL-' min-l, and finally to 0.68 g mL-' (5 min) at 0.03 g mL-' min-'; injection time, 5 s. The SFC data were quantitated by using standard solutions of solanesol in CH2C12. Analysis of Other ETS Components. The methods used to determine the concentrations of CO, fine particles, gas-phase nicotine and 3-ethenylpyridine, and particulate-phase nicotine in the chamber and indoor studies have been previously described (23, 5).
Results and Discussion Determination of Solanesol. Solanesol was quantitatively identified in environmental tobacco smoke particulate matter samples collected in the 30-m3 Teflon chamber by both GC and SFC (see Figures 1and 2). The marked peaks in the chromatograms have the same retention time as the standard solanesol (or its derivatized product). From the chromatograms, it is obvious that solanesol is a major component of the extractable organic compounds associated with particles of environmental tobacco smoke. The GC calibration data obtained by derivatizing different amounts of solanesol showed that peak area was linearly related to the nanomoles of solanesol. The equation derived from the least-squares linear regression fit of the data (r2 = 0.9997) was [solanesol] (nmol) = 1.20 f 0.55 + (5.0 f 0.8) X lo+ (nmol/area) X peak area The SFC calibration curve for solanesol gave a correlation coefficient of 0.9998. The relative standard deviation of three replicates was 4%. The detection limit was determined to be 0.3 ng of solanesol (3 times the signal/noise Environ. Sci. Technol., Vol. 24, No. 6, 1990
840
Table I. Concentration of Solanesol and the Ratio of Various Components of Environmental Tobacco Smoke to Solanesol in a Teflon Experimental Chamber and in Experiments at the Pierce Laboratory
cig. type
cig. no. [solanesol], nmol/m3 CO x 0.5
1R1
4
7.04 3.49 32.9 55.1 34.8 41.6 45.3 35.5 31.1
av 4
1R4F
av commercialc
54.0 50.5 28.7 25.6
av
mole ratio of various ETS components to solanesol in ETS RSPa nicotine(p)* nicotine(g)b 3-ethenylpyridine
9.2 14.1 8.7 10.9 11.2 11.2 11.6 7.8 10.6 f 1.9 7.4 7.5 7.5 f 0.1 13.1d 14.6d 12.9 f 1.1
Ratio is wg of particles/nmol of solanesol for fine particles (RSP). cPierce Laboratorv exDeriments. dEstimated from data in ref 24.
T
29.1
4.4 4.4 2.9 3.5 4.7 4.8 4.0
38.2 38.1 30.8 38.4 31.0 23.9 35.7 33.2 f 5.0 19.9 22.6 21.2 f 1.4 32.4 36.3 34.3 f 2.8
173 145 112 120
16.2 20.7 18.7 19.1 23.4
111
168 155
4.1 f 0.6 6.0 4.2 5.1 f 0.9
141 f 24 107 101 104 f 3 30 35 33 f 4
1.4
1.3 1.4 f 0.1
19.6 f 2.4 23.4 18.9 21.2 f 2.3 15.4 14.2 14.8 & 0.8
* Nicotine(p), particulate nicotine: nicotine(g), gaseous nicotine. 0
-E0
'
\
--
40
30
0
a
E -0m
20
20
10
10
v)
Y
0
0
1
2
3
Time, hr
4
1
2
Time,
3
4
hr
Figure 3. Concentration of solanesol in the experimental chamber during a 4-h period after the combustion of four cigarettes. (A) No UV light. (e) UV lights on. 0
32 min
Flgure 2. SFC chromatogram of a methylene chloride extract of collected particles of environmental tobacco smoke. Condltions: see text.
ratio). The concentrations of solanesol determined by the two analytical techniques were in agreement, the ratio of the concentration determined by GC to the concentration determined by SFC being 1.10 f 0.12. The precision of the determination of solanesol in samples of environmental tobacco smoke was 10% for both techniques. The resulting limit of detection and uncertainty in the concentration of solanesol for a 6-h sample collected at 30 sLpm is +=IO%[solanesol] + 0.1 nmol/m3. Chamber Experiments. Figure 3A shows the experimentally determined concentrations of particulate-phase solanesol during a 4-h period after combustion of four 1R1 cigarettes in the 30-m3 Teflon chamber. As shown, solanesol was stable over the time period studied. The slight drop in concentration is due to loss of particles to the walls of the chamber (23). Solanesol in environmental tobacco smoke particles in the Teflon chamber was found to be reactive in the presence of intense UV light (5). When the UV light system of the chamber was turned on to simulate midday solar radiation, solanesol concentrations were observed to quickly decay (Figure 3B). This situation is not expected to be important in indoor environments. N
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The concentration of solanesol compared to other constituents of the environmental tobacco smoke as a function of number of cigarettes burned in the Teflon chamber is given in Table I. The results are given as ratios because the volume of the collapsible Teflon bag varied from 15 to 30 m3 in the various experiments. The ratio of solanesol to other constituents of the smoke is independent of the number of cigarettes burned. The concentration of solanesol in ETS generated in the chamber experiments is 1.9 f 0.3 wt % for 1R1 and 3.0 f 0.2 wt % for 1R4F cigarettes. The value for 1R4F compares well with the value of 3.5-4.0 w t 76 previously reported by Ogden et al. (18, 19). The relative ratios of the other components measured in the Teflon chamber experiments (Table I) are comparable for the two types of cigarettes and agree with results we have previously reported (5, 6, 23). Specifically, the ratios of RSP, and gas-phase (and total) nicotine to CO are the same for the two reference cigarettes. However, smoking the 1R4F cigarette produces 74% more particulate-phase nicotine and 53% more 3-ethenylpyridine (on a per mole of CO basis) than does smoking the 1R1 cigarette. The results obtained in the Pierce Laboratory chamber gave results for the mole ratio of CO, particulate mass, and 3-ethenylpyridine to solanesol similar to those obtained in the Teflon chamber for 1R1 and 1R4F cigarettes (Table
Table 11. Concentration of Solanesol and the Ratio of Various Components of Environmental Tobacco Smoke to Solanesol in Indoor Environments with Environmental Tobacco Smoke Present sampling location [solanesol], nmol/ms day 1 office A office B office Cd day 2 office A office B office C d disco day 1 disco day 2
CO x
mole ratio of various ETS components to solanesol in ETS RSP" nicotine(p)b nicotine(g)b 3-ethenylpyridine
3.9 3.7 0.5
40 26 119
28 25 68
0.75 2.9C 2.42
12.5 10.0 1.8
5.8 7.4 8.6
1.8 2.7 0.8 30.8 27.1
70 42 135 32 32
30 28 46 26 28
1.63 0.98 1.09 1.04 1.04
14.2 12.3 2.5 23.0 21.9
8.1 9.5 8.1 5.6 5.4
Ratio is rg of particles/nmol of solanesol for fine particles (RSP). Nicotine(p), particulate nicotine; nicotine(g), gaseous nicotine. Not included in regression analysis. Office remote from any active smoking.
I). The data from the Pierce Laboratory chamber experiments give a solanesol concentration of 2.2 f 0.2 wt % of the ETS particles. The small increase in the mole ratio of CO to solanesol is expected since some particle loss is expected during air recirculation in the Pierce Laboratory chamber (7,24). However, the mole ratio of gas- and particulate-phase nicotine to solanesol in the Pierce Laboratory chamber was only -25% of the average value obtained in the Teflon chamber at BYU. The significantly decreased ratio for gas-phase nicotine relative to solanesol can be attributed to the expected rapid removal of gasphase nicotine in the non-Teflon chamber (7-9). The decrease in the ratio of particulate-phase nicotine to solanesol may be due either to a loss of particulate-phase nicotine to the gas phase in the chamber associated with the reduction in gas-phase nicotine or to a decrease in the fraction of nicotine in the particulate phase in environmental tobacco smoke produced by a smoker as compared to the sidestream smoke produced by a smoking machine. Indoor Studies. The concentrations of solanesol, and other components of environmental tobacco smoke relative to solanesol, found in the indoor studies are given in Table 11. The mole ratio of CO to solanesol in the indoor environments studied (Table 11) was always significantly higher than the ratio seen in the chamber studies (Table I). This is due to the presence of CO from other sources in the indoor environments (6, I O ) . The average ratio of RSP to solanesol for the various chamber experiments was 30 f 7 pg of RSP/nmol of solanesol. The values seen in the indoor experiments agreed with this value for the disco and offices where smoking was present. The increase in the particulate-phase RSP to solanesol ratio in samples collected in the office remote from active smoking can be attributed to the increased importance of nonenvironmental tobacco smoke particles at this location. The average composition of solanesol in environmental tobacco smoke inferred from the data for the indoor samples with heavy smoking present is 27.5 f 1.8 pg of ETS particles/nmol of solanesol, or 1.7 f 0.1 w t % solanesol. This value agrees with the value of 1.6-3.6 wt 70 solanesol reported by Ogden et al. (19) for ETS in indoor environments. The mole ratio of particulate-phase nicotine to solanesol in the indoor environments, varying from 0.8 to 2.9 with average and median values of 1.5 and 1.0, respectively, (Table 11) was comparable to the mole ratio of 1.4 seen in the Pierce Laboratory chamber studies. The ratio of particulate-phase nicotine to solanesol or of 3-ethenylpyridine to solanesol for samples collected in the disco and office building does not appear to be dependent on the
proximity of the sampling site to smokers. However, the ratio of 3-ethenylpyridine to solanesol is lower than that seen in Pierce Laboratory chamber studies by a factor of 2. No data are available on the change in the distribution of nicotine between gas and particle phase as a function of different environments and residence times in a given environment, but it has been shown that the percent of nicotine present in the particulate phase in environmental tobacco smoke is variable (6). At least one factor controlling this variability is the rapid removal of gas-phase nicotine from indoor environments, resulting in an increased fraction of the nicotine being present in the particulate phase (6, 7,9, IO). Chemical changes in environmental tobacco smoke may also result in increased formation of particulate-phase nicotine as acidic compounds are formed from the gas-phase constituents of environmental tobacco smoke (23). Both of these effects will result in the ratio of gas-phase nicotine to solanesol being smaller than the average value of 123 seen in the Teflon chamber experiments. As shown in Table 11, the mole ratio of gas-phase nicotine to particulate-phase solanesol in the indoor environments studied varied from a high of 23 in the disco to a low of 2 in the office remote from smokers. These values are all consistent with the more rapid removal of gas-phase nicotine relative to the particulate phase of environmental tobacco smoke in indoor environments (6, 7, 9, 10). Linear regression lines for least-squares linear regression fit of the indoor data, assuming a zero intercept, result in the slopes 1.03 f 0.02 mol of nicotine(p)/mol of solanesol (r2= 0.997), 5.58 f 0.12 mol of 3-ethenylpyridine/mol of solanesol (1.2 = 0.994), and 22.3 f 0.7 mol of nicotine(g)/mol of solanesol (r2 = 0.991). The linear regression analyses are strongly influenced by the high concentrations in the disco. Linear regression analyses of the office data only result in the slopes 0.95 f 0.16 mol of nicotine(p)/mol of solanesol (r2= 0.39), 7.2 f 0.5 mol of 3-ethenylpyridine/mol of solanesol (r2= 0.86), and 11.6 f 0.9 mol of nicotine(g)/mol of solanesol (r2 = 0.92). The regression analyses for the two data sets agree for particulate-phase nicotine and 3-ethenylpyridine. However, the ratio of gas-phase nicotine to solanesol appears to decrease as the solanesol,particulate-phase nicotine, and 3-ethenylpyridine all have similar decay rates in indoor environments. This suggests that the solanesol, particulate-phase nicotine, and 3-ethenylpyridine all have similar decay rates in indoor environments. This result is in agreement with studies in a controlled indoor environment (7). Gas-phase nicotine appears to be removed from the indoor environments at a faster rate than these compounds. Environ. Sci. Technol., Vol. 24,
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Conclusions Solanesol, a characteristic compound in Solanaceae family plants and expected to be present in indoor particles only in environmental tobacco smoke, is easily detected in air even at low concentrations of environmental tobacco smoke. The concentration of solanesol parallels that of particulate-phase nicotine and 3-ethenylpyridine in indoor environments. The concentration of solanesol in particles in indoor environments dominated by ETS is consistent with that found in chamber studies. The results reported here indicate that solanesol is a suitable tracer for the particles of environmental tobacco smoke. Acknowledgments
Appreciation is expressed to John W. Crawford for technical assistance. Registry No. CO, 630-08-0; solanesol, 13190-97-1; nicotine, 54-11-5; 3-ethenylpyridine, 1121-55-7.
Literature Cited (1) National Research Council Environmental Tobacco Smoke. Measuring Exposure and Assessing Health Effects; National Academy Press: Washington, DC, 1986. (2) The Health Consequences of Involuntary Smoking, A Report of the Surgeon General;US. Department of Health and Human Services: Washington, DC, 1986. (3) Eudy, L. W.; Thome, F. A.; Heavner, D. L.; Green, C. R.; Ingebrethsen B. J. Proceedings, 79th Annual Meeting of the Air Pollution Control Association; 22-27 June, Minneapolis, MN, 1986; Paper 86-38.7. (4) Eatough, D. J.; Benner, C.; Mooney, R. L.; Bartholomew, S.; Steiner, D. S.; Hansen, L. D.; Lamb, J. D.; Lewis, E. A. Proceedings, 79th Annual Meeting of the Air Pollution Control Association;22-27 June, Minneapolis, MN 1986; Paper 86-68.5. ( 5 ) Eatough, D. J.; Benner, C. L.; Bayona, J. M.; Caka, F. M.; Richards, G.; Lamb, J. D.; Lee, M. L.; Lewis, E. A.; Hansen, L. D. Environ. Sci. Technol. 1989, 23, 679-687. (6) Eatough, D. J.; Benner, C. L.; Tang, H.; Landon, V.; Richards, G.; Caka, F. M.; Crawford, J.; Lewis, E. A.; Hansen, L. D.; Eatough, N. L. Environ. Int. 1989,15(1-6), 19-28. (7) Tang, H.; Eatough, D. J.; Lewis, E. A.; Hansen, L. D.; Gunther, K.; Belnap, D.; Crawford, J. The Generation and Decay of Environmental Tobacco Smoke Constituents in an Indoor Environment. Proceedings, EPAIA WMA Symposium on the Determination of Toxic and Related Air Pollutants; Air and Waste Management Association, 1989; pp 596-605. (8) Thome, F. A.; Heavner, D. L.; Ingebrethsen, B. J.; Eudy, L. W.; Green, C. R. Proceedings, 79th Annual Meeting o f
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the Air Pollution Control Association; 22-27 June, Minneapolis, MN, 1986, Paper 86-37.6. (9) Lewis, E. A.; Tang, H.; Crawford, J. W.; Hansen, L. D.; Eatough, D. J. Proceedings, 81st Annual Meeting of the Air Pollution Control Association;19-24 June, Dallas, TX, 1988, Paper 88-76.9. (10) Eatough, D. J.; Hansen, L. D.; Lewis, E. A. Combustion Processes and the Quality of the Indoor Environment;Air and Waste Management Association, 1989; pp 183-200. (11) Badre, E.; Guillermo, R.; Abran, N.; Bourdin, M.; Dumas, C. Ann. Pharm. Fr. 1978, 36,443-452. (12) Eatough, D. J.; Jones, K.; Tang, H.; Lewis, E. A.; Hansen, L. D.; Eatough, N. L.; Ogden, M. W. Proceedings, EPAI APCA Symposium on Measurement of Toxic and Related Air Pollutants;Air Pollution Control Association, 1988; pp 739-749. (13) Caka, F. M., Eatough, D. J.; Lewis, E. A.; Tang, H.; Crawford, J. An Intercomparison of Sampling Techniques for Nicotine in Indoor Environments. Enuiron. Sci. Technol., in press. (14) Spengler, L. D.; Treitman, R. D.; Testeson, T. D.; Mage, D. T.; Soczek, M. L. Environ. Sei. Technol. 1985, 19, 700-707. (15) Kirk, P. W. W.; Hunter, M.; Baek, S.0.;Lester, J. N.; Perry, R. Indoor and Ambient Air Quality;Perry, R., Kirk, P. W., Eds.; Selper Ltd.: London, 1988; pp 99-112. (16) Johnston, R. A. W.; Plimmer, J. R. Chem. Rev. 1959,59, 885. (17) Rodgman, A.; Cook, L. C.; Chappell, C. K. Tobacco Sci. 1960, 5, 1. (18) Ogden, M. W.; Maiolo, K. C. Indoor and Ambient Air Quality;Perry, R.; Kirk, P. W., Eds.; Selper LM.: London, 1988; pp 77-88. (19) Ogden, M. W.; Maiolo, K. C. HRC CC, J. High Resolut. Chromatogr. Chromatogr. Commun. 1988, 11, 341-343. (20) Severson, R. F.; Ellington, J. J.; Scholtzhauer, P. F.; Arrendale, R. F.; Schepartz, A. I. J . Chromatogr. 1977,139, 269. (21) Fjeldsted, J. C.; Lee, M. L. Anal. Chem. 1984,56, 619A628A. (22) Peaden, P. A.; Fjelsted, J. C.; Lee, M. L.; Springston, S.R.; Novotny, M. Anal. Chem. 1982,54,1090-1093. (23) Benner, C. L.; Bayona, J. M.; Caka, F. M.; Tang, H.; Lewis, L.; Crawford, J.; Lamb, J. D.; Lee, M. L.; Lewis, E. A.; Hansen, L. D.; Eatough, D. J. Environ. Sci. Technol. 1989, 23,688-699. (24) Leaderer, B. P.; Cain, W. S.; Isseroff, R.; Berglund, L. G. Atmos. Environ. 1984, 18, 99-106. Received for review April 25,1989. Revised manuscript received November 7,1989. Accepted January 24,1990. This research was supported by R. J. Reynolds Tobacco, USA, and the Center for Indoor Air Research through grants to Hart Scientific Inc.
