VI.
ATMOSPHERIC PERSISTENCE
Among other factors, the combustibility of tobacco components, insufficient supply ofoxygen, and the existence of a temperature gradient in the burning cone, makes ETS a
mixture of several thousand compounds. Due to the complex chemical nature of ETS, a
discussion of the atmospheric persistence of the “mix” as a whole is not practical.
However, there are data on the atmospheric reactions that occur to several groups of
ETS-related chemicals. Therefore, in this chapter we provide a general discussion ofwhat is known about the atmospheric persistence of chemical groups within ETS,
including nicotine, N-Nitrosamines and PAHs.
Studies show that the combustion of cigarettes include at least three important types ofreactions, including: pyrolysis, pyrosynthesis, and distillation (NIH, 1998). The result of
these reactions is the production of thousands of gaseous and particle constituents.
Eventually, this complex mixture undergoes additional chemical reactions as the mix is
diluted with ambient air, yielding individual compounds with their own atmospheric
lifetimes. According to the Morawska et al. (1997) chamber and indoor environment
study, the lifetime of the mixture of ETS constituents in the air may be up to several
hours depending on the air ventilation rate, humidity, and atmospheric conditions.
A.

ATMOSPHERIC REACTIONS OF GASEOUS SPECIES

Gaseous ETS constituents can react in the atmosphere with other pollutants andsunlight to form new chemical species (see Table III-2 in Chapter III for a list of gaseouscomponents found in ETS; Appendix A contains a comprehensive list). For example,
1,3-butadiene can initially react in the atmosphere with the hydroxyl radical (OH), nitrate
radical (NO3), and ozone (O3) to form acrolein and formaldehyde (Atkinson, 1994; Skovet al., 1992). Gaseous species may also transform into particle phase species. For
example, gas phase ammonia can react with gaseous nitric acid to form particulateammonium nitrate (Atkinson, 1995). Exposure to ammonium nitrate has been found tocause burning or irritation of eye and skin (ARB, 1997a). Alternatively, as ETS ages,
semi-volatile constituents of ETS, such as nicotine and neophytadiene, may shift fromparticulate phase to the gaseous phase.
Gaseous ETS components primarily react with the following:
!
!
!
!
!
!
!

Sunlight through photolysis
O3 (ozone)
OH radical during the daylight hours
NO3 radical during the nighttime hours
Gaseous nitric acid (HNO3)
Nitrogen dioxide (NO2)
Hydroperoxy radical (HO2) mainly during afternoon/evening hours

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Important reaction processes for most gas-phase organic compounds are photolysis
and subsequent reaction with O3, as well as the OH and NO3 radicals. For a few
compounds, one or more of the other reactive chemical species (HO2, NO2, and/or
HNO3) may react at significant rates. For example, HO2 radicals react withformaldehyde, acetaldehyde, and glyoxal, NO2 reacts with conjugated dienes, andgaseous HNO3 reacts with the amines. Table VI-1 provides examples of theatmospheric lifetimes and the dominant removal processes for some of the gaseous
species found in ETS.
Table VI-1
Estimated Atmospheric Lifetimesof Selected ETS Constituents
1,3 Butadiene
Acetaldehyde
Acrolein
BenzeneFormaldehyde
N-Nitrosodimethylamine
Toluene
PAHs (gas phase)

Dominant Removal Process
OH radical
OH radical
OH radical
OH radical
Photolysis
Photolysis
OH radical
OH radical

Atmospheric Lifetime
2 hours1/
9 hours1/
7 hours1/
10 days2/
4 hours
5 minutes
2.5 days
3-27 hours

Source: ARB, 1998.
1/ 12-hour average daytime (OH of 2.0x 106 molecule/cm3 )2/ 1 day = 12-hour of OH of 2.0x 106 molecule/cm3

Gaseous species absorbed by particles may be unavailable for further chemical
reaction. Gaseous species adsorbed to particles may be degraded by photolysis andreaction with trospheric O3, dinitrogen pentaoxide (N2O5), NO2, HNO3, nitrous acid
(HNO2), sulfuric acid (H2SO4), and hydrogen peroxide (H2O2).
B.

ATMOSPHERIC REACTIONS OF PARTICULATE SPECIESParticles in the range of 0.01-10 µm are often referred to as PM10. Typically, all of the
ETS associated particles fall in the range of between 0.01 and 1.0 µm (U.S. EPA,
1992). ETS contains particulate species which have their own atmospheric persistence
rates based on the particle size. The two most important processes affecting particle
ETS species in the atmosphere are:!
!

Dry and wet deposition (i.e., physical removal) of particles, andAtmospheric transformations of species adsorbed to the particles.

Dry deposition is broadly defined as the transport of air pollutants from the atmosphere
onto surfaces in the absence of precipitation (Davidson and Wu, 1989; Seinfeld andPandis, 1998). Major factors affecting dry deposition are atmospheric turbulence,chemical, and physical properties of the air pollutants and the nature of the depositing

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surface. Particles in the size range of 0.05 to 1 µm are expected to reside in theatmosphere for long time periods and can be transported over long distance(Cohen, 1998).
Virtually complete removal of particles in the range of 0.1 to 10 µm in diameter is
expected by wet deposition (Leuenberger et al.,1985, Ligocki et al., 1985 a,b). Since
ETS particles are in this size range (0.1-1µm), they are expected to be efficiently
washed from the atmosphere by wet deposition. Wet deposition occurs due to events
such as rain, cloud, fog, or snow.
C.

NICOTINE

Nicotine is the principal alkaloid in tobacco and a major contributor to the addictive
properties of tobacco. In ETS, studies report that nicotine is most commonly found in
the gas phase within the environment (Eudy et al., 1986; Thome et al., 1986; Eatough etat., 1986; Hammond et al., 1987). Organic compounds with vapor pressure between
10-6 and 10 Pascals (Pa) at ambient temperatures are classified as semi-volatile organic
compounds. At 298 ºK, nicotine has a vapor pressure of 2.7 Pa and is almost entirely
present in gas phase (Von Loy et al., 2001). Less than five percent of ETS nicotine has
been associated with the particulate phase (Jenkins et al., 2000). Also, in sidestream
smoke, the alkaline nature of ambient air leads to gas phase nicotine rather than in theparticulate phase.
The semi-volatile constituent of ETS, such as nicotine, exhibit different atmosphericpersistency depends on environmental conditions. In ambient air, nicotine may reactwith photochemically generated hydroxyl radicals and with ozone. The reported half-lifeof nicotine in the ambient atmosphere is approximately 1 day (Spectrum Chemical Fact
Sheet, 2003).
In indoor air, gas phase nicotine is rapidly diffuse to surrounding surfaces with which itinteracts and expected to be removed from the environment at a faster rate than otherETS components (Eudy et al., 1986; Eatough et al., 1986). Studies show that the
nicotine level decreases rapidly as consequence of sorptive uptake on different
surrounding surfaces (Eatough et al., 1986; Piade et al., 1999; Von Loy et al., 2001).
Therefore, nicotine is a reasonable indicator of ETS exposures occurring within theprevious few hours, with its indoor half-life of approximately two hours (Trinh andHuynh, 1989). Research also indicates that sorbed nicotine present on surrounding
materials, such as walls and carpets, may be re-emitted to the environment over time
(Trinh and Huynh, 1989). According to the Piade et al. (1999) study, as much as 1 mgof nicotine can be adsorbed and re-emitted from 1 m2 of cotton cloth over a few hours.
The Von Loy et al. (2001) chamber experiments also observed desorption of nicotine
from surrounding materials. After flash evaporation of nicotine in a 20 m3 environmental
test chamber with a carpet floor covering (measured nicotine air concentration of 4.4µg/m3), the chamber was flushed with clean air for 3 days. After resealing the chamber,the nicotine concentration slowly rose back to 1 µg/m3, which demonstrates the effect of
nicotine being re-emitted from surrounding material surfaces.
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D.

TOBACCO-SPECIFIC N-NITROSAMINES

While nicotine has not been identified as a carcinogen, several tobacco-specificnitrosamines (TSNAs), which are derived from nicotine and other tobacco alkaloids,
may be carcinogenic (Hecht and Hoffmann, 1988). TSNAs (see Figure VI-1) are formedby N-nitrosation of nicotine during the curing, processing, fermentation, and combustionof tobacco products (IARC 1986; Ashley et al., 2003). The yield of TSNA from smoking
depends on the nitrate content of tobacco. Certain flue-cured tobaccos exposed to NOxduring the curing process contain higher levels of TSNAs (Ashley et al., 2003).
Figure VI-1
Nicotine Conversion

NNN : N’-nitrosonornicotine
NNK: 4-(methylnitrosamino-)-1-(3-pyridyl)-1-butanone
NAT: N’-nitrosoanatabine

N’-nitrosonornicotine (NNN) and 4-(methylnitrosamino-)-1-(3-pyridyl)-1-butone (NNK)are believed to be the most potent carcinogens of the TSNA class (Ashley et al., 2003).
N-nitroso compounds are degraded in the presence of ultraviolet and visible light.
When heated to decomposition, these compounds emit toxic fumes of nitrogen oxides(NTP, 2002).
E.

PAH AND PAH-DERIVATIVES

Researchers have identified at least ten polycyclic aromatic hydrocarbon (PAH) isomers
in ETS, which have been identified as cancer causing toxic air contaminants (Hoffmannand Hoffmann, 1997; OEHHA, 1997). Some PAHs react with NOx emissions in theatmosphere to mutate to form nitro-derivative PAHs (ARB, 1994). Both gas andparticle phase PAHs have been measured in ETS (Gundel et al., 1995). Table VI-2

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shows a list of identified gaseous and particulate PAHs that have been identified in
ETS.
Table VI-2
PAHs Detected in ETS
Gas-Phase PAHs
1-methylnaphthalene
2-methylnaphthalene
Anthracene1/
Benz[a]anthracene1/
Chrysene1/
Fluoranthene1/
Fluorene
Naphthalene
Phenanthrene
Pyrene1/

Particle-Phase PAHs
1,2-benzofluorene
Anthracene
Benz[a]anthracene
Benzo[a]pyrene
Benzo[b]fluoranthene
Benzo[k]fluoranthene
Chrysene
Fluoranthene
Phenanthrene
PyreneTriphenylene

Source: Gundel et al., 1995.
1/ PAHs are distributed between the gas and particle phases.

One of the most potent cancer-causing PAHs in ETS is benzo[a]pyrene.
Benzo[a]pyrene exists almost entirely in the particle phase in the atmosphere with asize of three µm or less and, therefore, subject to wet and dry deposition (ARB, 1997b).
The average half-life of particle benzo[a]pyrene in the atmosphere is estimated to beabout 3.5 to 10 days and lifetime of 5 to 15 days (ARB, 1997b). Other lifetimes of PAHs
are shown in Table VI-3.
Table VI-3
Estimated Atmospheric Lifetimesof Selected PAHs
PAHs in ETS
1- methylnaphthalene
2-methylnaphthalene
Anthracene
Fluoranthene
PyreneLifetime due to reaction with:OH a/
NO3 b/
3.5 hrs
50 days
3.6 hrs
40 days
1.4 hrs~3.7 hrs d/~85 days~3.7 hrs d/~30 days

O3 c/>125 days>40 days

Source: ARB, 1998.
a/ For a 12-hr daytime average OH radical concentration of 1.5x106 molecule cm-3 (Prinn et al.,1987).
b/ For a 12-hr average nighttime NO3 radical concentration of 2.4x108 molecule cm-3 and an
NO2 concentration of 2.4x1012 molecule cm-3 (Atkinson et al., 1986).
c/ For a 24 hr average O3 concentration of 7x1011 molecule cm-3 (Logan, 1985).

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d/ Using estimated OH radical reaction rate constant correlation with ionization potential(Biermann et al., 1985; Arey et al., 1990; Atkinson et al., 1990).

Volatile, 2- to 4-ring PAHs exist in the atmosphere mostly in the gas phase (Atkinson
and Arey, 1994). The gas-phase PAHs react with hydroxyl (OH) radicals, NO3 radicals,
and ozone in the atmosphere, with the OH radical reaction generally dominating as the
PAHs loss process (Atkinson and Arey, 1994). The products of the OH radical reactions
with PAHs include formation of hydroxyl-PAH, nitro-PAH, and ring-opened dicarbonyls(ARB, 1997b). The estimated half-life of the gas phase 2- and 4-ring volatile PAHs in
the atmosphere due to reaction with the OH radical are in the range of 2 to 19 hours
and have a lifetime of 3 to 27 hours, (Atkinson and Arey, 1994).

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REFERENCES
ARB, (1994). Benzo[a]pyrene as a Toxic Air Contaminant. Staff Report. Executive
Summary, California Air Resources Board.
ARB, (1997a). California Air Resources Board. Toxic Air Contaminant Identification List
Summaries, Ammomium Nitrate. pp.55.
ARB, (1997b). California Air Resources Board. Toxic Air Contaminant Identification List
Summaries, Polycyclic Organic Matter. pp. 803.
ARB, (1998). California Air Resources Board. Proposed Identification of Diesel Exhaust
as a Toxic Air Contaminant. Part A. Exposure Assessment. pp. A-71.
Arey J., Atkinson R., Aschmann S.M., Schuetzle D. (1990). Experimental Investigationof the Atmospheric Chemistry of 2-Methyl-1-nitronaphthalene and a Comparison ofPredicted Nitroarene Concentrations with Ambient Air Data. Polycyclic Aromat.
Compounds. Vol. 1, pp.33-50.
Ashley D.L., Beeson M.D., Johnson D.R., McCraw J.M., Richter P., Pirkel J.L.,
Oechacek T.F., Song S., Watson C.H. (2003). Tobacco-Specific nitrosamines intobacco from U.S. brand and non-U.S. brand cigarettes. Nicotine & Tobacco Research.
Vol 5, pp. 323-331.
Atkinson R. (1994). Gas-phase tropospheric chemistry of organic compounds.
J. Phys. Chem. Ref. Data. Monograph 2. pp.1-216.
Atkinson R., Arey J. (1994). Atmospheric chemistry of gas-phase polycyclic aromatichydrocarbons: Formation of atmospheric mutagens. Environ. Health Perspect.
Vol. 102 (Suppl. 4), pp.117-126.
Atkinson R. (1995). Personal review of the Air Resources Board’s Toxic Air
Contaminant Identification List compounds. University of California, Riverside.
Atkinson R. (1986). Kinetics and Mechanisms of the Gas-phase Reactions of theHydroxyl Radical with Organic Compounds under Atmospheric Conditions. Chem. Rev.
Vol. 86, pp. 69-201.
Atkinson R. (1990). Gas-phase Tropospheric Chemistry of Organic Compounds: a
Review. Atmos. Environ. Vol. 24A, pp. 1-41.
Biermann H.W., Mar Leod H., Atkinson R., Winer A.M., Pitts Jr. J.N. (1985). Kinetics ofthe Gas-phase Reactions of the Hydroxyl Radical with Naphthalene, Phenanthrene, andAnthracene. Envirn. Sci. Technol. Vol. 19, pp. 244-248.

PERSISTENCE

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June 2005

Cohen Y. (1998). Environmental Multimedia Transportation Phenomena. Chapter 11.
Department of Chemical Engineering. University of California, Los Angeles. Multimedia
Envirosoft Corporation.
Davidson C.I. and Wu Y.L. (1989). "Dry Deposition of Trace Elements," in Control andFate of Atmospheric Heavy Metals, J.M. Pacyna and B. Ottar, editors, NATO ASI
Series, Series C, Volume 268, Kluwer Academic Publishers, Dordrecht. pp. 147-202.
Eatough D.J., Benner C., Mooney R.L., Bartholomew D., Steiner D.S., Hansen L.D.,
Lamb J.D., Lewis E.A. (1986). Gas and particle phase nicotine in environmental tobaccosmoke. Proceedings, 79th Annual Meeting of the Air Pollution Control Association.
Paper 86-68.5, Pittsburgh, PA.
Eatough E.J., Benner C.L.,Tang H., Landon V., Richards G. (1989). The ChemicalComposition of Environmental Tobacco Smoke. III. Inedtification of Conservative
Tracers on Environmental Tobacco Smoke. Environmental International. Vol. 15, pp.
19-28.
Eudy L.W., Thorne F.W., Heavner D.K., Green C.R., Ingebrethsen B.J. (1986). Studies
on the vapor-particulate phase distribution of environmental nicotine by selective
trapping and detection methods. Proceedings, 79th Annual Meeting of the Air Pollution
Control Association. Paper 86-38.7, Pittsburgh, PA.
Gundel L.A., Mahanama K.R.R., Daisy J.M. (1995). Semivolatile and Particulate
Polycyclic Aromatic Hydrocarbons in Environmental Tobacco Smoke: Cleanup,
Speciation, and Emission Factors. Environ. Sci. Technol. Vol. 29, pp. 1607-1614.
Hammond S.K., Leaderer B.P., Roche A.C., Scjemker M. (1987). Collection andAnalysis of Nicotine as a Marker for Environmental Tobacco Smoke. Atmospheric
Envionment. Vol. 21, No. 2, pp. 457-462.
Hecht S.S., Hoffmann D. (1988). Tobacco-specific nitrosamines, an important group ofcarcinogens in tobacco and tobacco smoke. Carcinogenesis. Vol. 9, pp. 875-884.
Hoffmann D., Hoffmann I. (1997). The changing cigarette, 1950-1995. Journal of
Toxicology and Environmental Health. Vol. 50(4), pp.307-364.
IARC, (1986). International Agency for Research on Cancer IARC Monographs on the
Evaluation of the Carcinogenic Risk of Chemicals to Humans. Tobacco Smoking. Vol.
38. pp.110-114. Lyon, France: IARC.
Jenkins R.A., Guerin M.R., Tomkins B.A. (2000). The Chemistry of Environmental
Tobacco Smoke: Composition and Measurement. Lewis Publishers. Chelsea, Michigan.
Krol M., Van Leeuwen P.J., Lelieveld J. (1998). Global OH trend inferred frommethychloroform measurements. J. Geophys. Res., 103, 10697-10711.

PERSISTENCE

VI-8

June 2005

Leuenberger D., Ligocki M.P., Pankow J.F. (1985). Trace organic compounds in rain.
4.Identities, concentrations and scavenging mechanisms for phenols in urban air andrain. Environ. Sci. Technol. Vol. 19, pp. 1053-1058.
Ligocki M.P., Leuenberger C., Pankow J.F. (1985a). Trace organic compounds in rain –III. Particle scavenging of neutral organic compounds. Atmos. Environ. Vol. 19,
pp. 1619-1626.
Ligocki M.P., Leuenberger C., Pankow J.F. (1985b). Trace organic compounds in rain –II. Particle scavenging of neutral organic compounds. Atmos. Environment. Vol. 19,
pp. 1609-1617.
Logan J.A. (1985). Tropospheric ozone: seasonal behavior, trends, and anthropogenic
influence. J. Geophys. Res. Vol. 90, pp. 10463-10482.
Morawska L., Jamriska M., Bofinger N. (1997). Size characteristics and ageing of theenvironmental tobacco smoke. The Science of the Total Environment. Vol. 196, pp.4355.
NIH, (1998). Cigars Health Effects and Trends. National Institutes of Health; National
Cancer Institute Smoking and Tobacco Control Monograph 9.
NTP, (2002). National Toxicology Program. N-Nitrosonornicotine Report on
Carcinogens. Tenth Edition; U.S. Department of Health and Human Services, Public
Health Service, National Toxicology Program, December 2002.
OEHHA (Office of Environmental Health Hazard Assessment) (1997). Health Effects of
Exposure to Environmental Tobacco Smoke. Final Report . California Environmental
Protection Agency.
Piade J.J., D’andres D., Sanders E.B. (1999). Sorption Phenomena of Nicotine andEthenylpyridine Vapors on Different Materials in a Test Chamber. Environ. Sci.
Technol. Vol. 33, pp. 2046-2052.
Prinn R., Cummold D., Rassmussen R., Simmonds P., Alyea F., Crawford A., Fraser P.,
Rosen R. (1987). Atmospheric trends in methylchloroform and the global average forthe hydroxyl radical. Science. Vol. 238, pp. 945-950.
Prinn R.G., Huang J., Weiss R.F., Cunnold D.M., Fraser P.J., Simmonds P.G.,
McCulloch A., Harth C., Salameh P., O’Doherty S., Wang R.H.J., Porter L., Miller B.R.
(2001). Evidence for substantial variations in atmospheric hydroxyl radicals in the past
two decades, Science. Vol. 292, pp. 1882-1999.
Seinfeld J.H., Pandis S.N. (1998). Atmospheric Chemistry and Physics: From Air
Pollution to Climate Change. John Wiley and Sons, New York.

PERSISTENCE

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June 2005

Skov H., Hjoth J., Jensen N.R., Restelli G. (1992). Products and mechanisms of thereactions of the nitrate radical (NO3) with isoprene, 1,3-butadiend, and 2,3-dimethyl-1,3butadiene in air. Atmos. Environ. Vol. 26A, pp. 2771-2783.
Spectrum Chemical Fact Sheet (2003). http://www.speclab.com/compound/c54115.htm
Thome F.A., Heavner D.L., Ingebrethsen B.J., Eudy L.W., Green C.R.(1986).
Environmental Tobacco smoke monitoring with an atmospheric pressure chemical
ionization mass spectrometer/mass spectrometer coupled to a test chamber.
Proceedings, 79th Annual Meeting of the Air Pollution Control Association. Paper 8637.6, Pittsburgh, PA.
Trinh V.D. and Huynh C.K. (1989). Sidestream Tobacco Smoke Constituents in Indoor
Air Modeled in an Experimental Chamber-Polycyclic Aromatic Hydrocarbons.
Environmental International. Vol. 15, pp. 57-64.
U.S. EPA (1992). U.S. Environmental Protection Agency. Respiratory Health Effects ofPassive Smoking: Lung Cancer and Other Disorders. EPA/600/6-90/006F. EPA Officeof Research and Development, Washington, DC.
Von Loy M.D., Riley W.J., Daisey J.M., Nazaroff W.W. (2001). Dynamic Behavior of
Semivolatile Organic Compounds in Indoor Air. 2. Nicotine and Phenanthrene with
Carpet and Wallboard. Environ. Sci. Technol. Vol. 35, pp. 560-567.

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