A rapid method for the chromatographic analysis of volatile organiccompounds in exhaled breath of tobacco cigarette and electroniccigarette smokers

9 Pages·2015·1.114 MB·English

by  Esther Marco, Joan O. Grimalt

JournalofChromatographyA,1410(2015)51–59

ContentslistsavailableatScienceDirect

Journal of Chromatography A

journal homepage: www.elsevier.com/locate/chroma

A rapid method for the chromatographic analysis of volatile organic

compounds in exhaled breath of tobacco cigarette and electronic
(cid:2)
cigarette smokers

EstherMarco,JoanO.Grimalt∗

InstituteofEnvironmentalAssessmentandWaterResearch(IDÆA),SpanishCouncilforScientificResearch(CSIC),JordiGirona,18,08034Barcelona,

Catalonia,Spain

a r t i c l e i n f o a b s t r a c t

Articlehistory: Amethodfortherapidanalysisofvolatileorganiccompounds(VOCs)insmokefromtobaccoandelec-
Receiv ed15March2015 tr onicciga ret tes andin exhaled b reathof userso fthesesmo kingsy ste mshas been develo ped. Both
AReccceepivteedd i2n6 r Jeuvliyse2d0 1fo5rm 23 July 2015 dispos able and re char ge able e-cig arettes w ere co nsi dered. Smoke o r breath w ere colle cted in Bio-V OCs.
VOCswerethendesorbedinTenaxcartridgeswhichweresubsequentlyanalyzedbythermaldesorption
Availableonline29July2015
coupledtogaschromatography–massspectrometry.Themethodprovidesconsistentresultswhencom-

paringtheVOCcompositionsfromcigarettesmokeandtheequivalentexhaledbreathofthesmokers.
Keywords:
Thedifferencesincompositionofthesetwosampletypesareusefultoascertainwhichcompoundsare
Volatileorganiccompounds
retainedintherespiratorysystemaftertobaccocigaretteore-cigarettesmoking.
Thermaldesorption
EElxehcatrleodni bcr ceiagtahrettes breSatrtohnwg hdeifnfecroemncpeasr winegrew iotbhsethrvoesde oinf eth-cei gVaOreCt tceomsmpooksiitnigo.nT ohfe tfoobramcceor icnigvaorlevtetde tsrmanoskfee rasnodf eaxmhaulechd
Tobacco largerb urden oforganic comp ounds in tosmokers, including ben zene,to luene,na phthalene an d other

Nicotine pollutantsofgeneralconcern.e-Cigarettesledtostrongabsorptionsofpropyleneglycolandglycerinin

theusersofthesesystems.Tobaccocigaretteswerealsothoseshowinghighestconcentrationdifferences

betweennicotineconcentrationsinsmokeandexhaledbreath.Theresultsfromdisposablee-cigarettes

wereverysimilartothosefromrechargeablee-cigarettes.

©2015ElsevierB.V.Allrightsreserved.

1. Introduction frome-cigarettesmokershavebeendevelopedusingsolidphase

microextractioninsideabreathcollectiondevice[5]orexposure

Electroniccigarettes(e-cigarettes)aredesignedtotransfermix- chamberswhicharesubsequentlysampledbyabsorptionintosolid

tures of air and vapors into the respiratory system [1–3]. They phasesorptiontubes.Thesetubesarethenanalyzedbydesorption

useplasticormetalcylindersthatcontainelectronicvaporization intogaschromatographycoupledtomassspectrometry(GC–MS)

systems, a battery, in some cases, a charger, electronic controls [6].Inothercases,theabsorptioncartridgehasbeeninstalledat

and,optionally,replaceablecartridges.Differenthumectants,e.g. theoutletofasmokingmachineandtheretainedcompoundsare

propyleneglycolorglycerin,flavoringsandnicotineatvariouscon- elutedwithCS andmethanolforsubsequentanalysisbyGC–MS
2

centrationsaregenerallycontainedinthecartridges.Theycanbe [7].

disposable(Type1e-cigarette)orrechargeable(Type2e-cigarette). In the present study, we describe a simplified method using

Concern has been raised for the compounds incorporated into aBio-VOCsexhaledairsamplerdevelopedbytheUKHealthand

smokersasconsequenceofe-cigarettevaping. Safety Laboratory (Markes International Ltd, Llantrisant, UK) for

Exhaledbreath,namelythealveolarbreath[4],mayprovidesig- the comparison of the smoke generated by Type 1 and Type 2

nificant clues on the compounds that are retained in humans as e-cigarettes,tobaccocigarettesandtheexhaledbreathaftervap-

consequence of this activity. Studies on VOCs in exhaled breath ingorsmoking.Thisdevicehasbeenusedintheanalysisofboth

exhaled alveolar air and mouth air [8–15]. Now, we are using

BIO-VOCs for a rapid method of characterization of the volatile

organicconstituentsintobaccocigarettesande-cigarettes.Blend
(cid:2)PresentedattheXIVScientificMeetingoftheSpanishSocietyofChromatography typeAm ericantobacc oc igarette swithfilter s(le ngth83mm, length

andRelatedTechniques,1–3October2014,Barcelona,Spain.
∗ of filter 23mm, diameter 8mm) were used as test examples.
Correspondingauthor.Tel.:[phone];fax:[phone].
E-mailaddress: joan.gr imalt @ida ea.csic.es(J.O .Gr ima lt). Cigaretteswithlownicotinecontent(0.6mg),lowtar(8mg)and

http://dx.doi.org/10.1016/j.chroma.2015.07.094
0021-9673/©2015ElsevierB.V.Allrightsreserved.
52 E.Marco,J.O.Grimalt/J.Chromatogr.A1410(2015)51–59

low carbon monoxide (9mg) were chosen. The compounds ana- operatedatacarrierheliumflowof28.5mL/minandanoutletsplit

lyzedinthepresentstudyweremostlyinthegasphase.Theresults flowof27mL/min.Totalsplitratiowas95:1.

addtothecurrentknowledgeofexposureofsmokerstoorganic

compoundsthatsofarhavebeenmostlycharacterizedinparticu-
2.4. GC–MSoperationalconditions
latephasetransferprocesses[16–23].

The transfer line introduced the compounds into a Gas Chro-
2. Experimental
matograph 7890 (GC; Agilent Technologies Inc., Santa Clara, CA)

coupledtoaMassSpectrometer5975CInertXLMSD.TheGCwas
2.1. Samplingcartridges
equippedwithaDB-5MSUIcapillarycolumn(length60m;internal
diameter 0.32m m;filmt hic kness1(cid:2) m;Agile ntJ&W GC Co lumns).
Volatile organic compounds were concentrated by sorption
Helium(5Ngrade)wasthecarriergasataflowof1.5ml/min(con-
intostainlesssteelsorbentcartridges(89mmlong0.64cmouter
stant flow mode). The GC oven temperature program started at
diameter) packed with 200 mg of Tenax TA 35/60 mesh (Markes 40◦C (hold ingtime 10m in )then itincreasedt o150◦Ca t5◦C/m in
caInontndedrtnihtaeiotninoaentda3 lu3 Ls5tidn◦C,g P fhooenrlt3iuy0cmmlu (in5n,N .UI nKgrl)aa. tTdeher;ec 1so0on0rdb mietinlo/tmn cianinrgt)r caiydtc g3lee2ss0 tw◦hCee rsfeoe rpc r2aer h-- andA t otr 2a1n0sf◦eCr a litn 1e5 h◦ Cea/mt eidn t(ofi n2a8l0 h ◦oC ld cinargr iteimd et h1e0 cmoimn)p.o un ds from
tridg es w er e recon dit ion ed at 33 5◦C for 20 min wi th the same fl ow t2h3e0 G◦CC aton dth1e5 M0◦SC. ,Trhees pMeSc tsiovuelryc.eT ahnedM qSuaodpreuraptoeld teinmepleecratrtounreism wpearcet
carrier gas. Once cleaned, the cartridges were sealed with brass
mode.Thedetectorwasfullscannedbetween30and380amu.
SwagelockstorageendcapsfittedwithPTFEferrulesandstoredin

solvent-freecleanenvironments.

2.5. Compoundidentificationandquantification
2.2. Sampling

VOCswereidentifiedbasedonretentiontimesandlibraryiden-
Exhaled breath was sampled with a Bio-VOC system 30min tification ofth emasssp ectrum fr omeach chrom atog raphic peak
aftertobacc ocigare tteo re-cigare ttesm o king.Toa voidme tab olic (NIST200 9,M as sSpec tralSearch Prog ram, version2.0f).Qua ntifi-
differ encesal lvolunte ers wereaske dtosmok ew ithth etobacco cationwas perfor medbyt heexte rnalstand ardmet hod.
cigarettesa nd Type1and 2e-c igarett es conside redi nth isstudy. Cal ibrat ion curves en com passed n ine calib ration solutions in
Peopleins pire dand ex pire d deeplythree times,then re tain edthe methanol (Me rck KG aA, Darmstadt , Ger many) at d ifferent co n-
breath for20san dbl ewintot heBio- VOCb odythr ough adisposa ble centration in the range between 0.5 and 200(cid:2) g/ ml. They were
cardbo ard m o uthp iecea tth eirh ighestc apaci ty.Thea ir remaining preparedfr om com merc ialsolutio ns:U STM odifi edGas olineR ange
intheBio- VOCwastran sf erred intothe sorbentc artr idg ebypush- Organics (1000 (cid:2)g/ml in m ethanol; Sup elco, Inc. Bellefont e, PA,
in gas crew-in plun gerthrough the Bio- VOCbo dy.Thisp roc edure USA), FIA Paraffi n Stan da rd (Accusta ndard In c., N ew Haven, CT),
was r epeatedfi vetimes ineach smo kingtest anda llexh aledVOCs and th e in dividua l standard s: 2-methylbut ane, 1-pen tene, c is-2-
were accumu lated inth e same cartridge .Th us,a to talvolum eof pen tene , trans-2-p entene and 4-methyl-1-pent ene, all gra de GC
750m Lofexhaled bre ath wasco llected. Standard (Sigma-AldrichC o.,St .Louis,Mo).
T oba cc ocigaret teand e-cig arettesmokeweresampledbycon- ACali brationSolution Loa din gRin g(CSLRTM,MarkesInterna-
necting the mouth o utle ts to the B io-VOC outl et. The s cre w-in tiona lLtd.,Llant risant,UK )wasus edto introduc etheca libration
plunger was usedto pullsmo ke into theBio-V OCcylin der. Then,the solutio n in to clean sor bent cart ridge s w hich allow ed controlled
tobacco ciga rette or e-c igarette sw ere removed andthe cartri dge vaporiza tion and p urging of the sol vent (c arrier g as flow at
wascon nectedto th eBio-VOCou tleta ndthescr ew- inp lugerwas 50ml/min du ring 3min). T he diffe rent sta ndard so lutio ns w ere
used topushth es mo kepresen tinth eBi o-VO Cintoth ecartr idge dir ectlyin troduce d intot heca rtridgesw hichwer esubsequ ently
whic hs orbed the VOCsfr omthes am ple .Thesam pled vol umewith analyzed intheTD- GC–M S.T hisallowe dthed eterm inationoflin-
thispr ocedure wa s150 mL. earconce nt ratio nrangesan dlim itsofde tect ion.Recoveries w ere
I ndoor amb ient air was also sampled for comparison using det erminedbyintr oductio nof standa rd solutionsi ntotheBio- VOCs
thisdevice .Thepro ced urew asth esamea sth atusedforto bacco heated at 5 0◦C . Repetitivit y was also determin ed b y s equential
ciga rette an d e- cigarette s mok e bu t wit ho ut co nnec ting any of analysi so fstand ardsintrodu cedin toth eBio-VOCs.
thosedev ices tothesorb entcart ridge .Inthis casethepro cedu re

wasrepeatedfourtimesandatotalvolumeof600mLwascollected.

3. Resultsanddiscussion

2.3. TransferoftheVOCintotheGC–MS

3.1. Exhaledbreathandairconcentrations

VOCstrappedinthesorbentcartridgesweretransferredwith

helium (5N grade; no inlet split flow) to a thermal desorption The gas chromatograms corresponding to indoor air from a

(TD)instrumentequippedwithaUnitySeries2ThermalDesorber building of Barcelona and exhaled breath of volunteers present

andanUltra50:50Multi-tubeAuto-sampler(MarkesInternational in this indoor environment without smoking are compared in
Ltd) .Th ecom poun dswerede sorbedfromth ecartrid gesat300◦C Fig . 1. Compou nd identificat ion is re ported in Tab le 1. Aceto ne

for 5min (desorption flow 40mL/min) and re-concentrated in a andisoprenewerethemaincompoundsinexhaledbreath.These

graphitized carbon sorbent cold trap (U-T11GPC-2S for General are two endogenous compounds usually present in this type of
Purpose;Ma rkesInt ernation alLtd )coo ledat−20◦C.T hisc oldtrap sam ple. Bothchroma togramsalso hadsom ecomm on pea kssu ch
was heat ed to 30 0◦C over 5m in w hile p ass ing a h elium flow of asbenze ne,t oluene,styrene, benz alde hyde, (cid:3)-limonen e,dec anal,

7.5ml/min(splitflow6ml/min)forVOCtransfertoanuncoatedand nonanoicacid,andasiloxaneseries.Benzeneandtoluenemaycon-

deactivatedfused-silicacapillarytransferlineof1mlength(inter- stitutetraceamountsofvehicularexhaustinthearea.Thesiloxane

nalandouterdiameters0.25and0.35mm,respectively)heatedat seriesmayrepresentsomebackgroundinputoftheanalyticalsys-
200 ◦C. Totals plitratiow as5 :1. tem. T he o ther com pound s may refle ct a r ela tion ship betw een

FortheType2e-cigaretteanalyses,inletsplitflowduringcar- in-dooratmosphericVOCsandexhaledbreathofresidentsinthis

tridgedesorptionwas50mL/minanddesorptiontrapconditions environment.
E.Marco,J.O.Grimalt/J.Chromatogr.A1410(2015)51–59 53

Table1

Compoundsidentifiedintobaccoandelectroniccigarettes.

N RT(min) Compound Nosmoking Tobacco e-cigaretteType1 e-cigaretteType2

Indoorair Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath
√ √ √ √ √ √ √
1 3.768 Sulfur –

dioxide + difluorodimethylsilane √
2 4.098 Butene isomer – – – √ – – – –
3 4.164 Buta-1,3-diene – – – √ – – – –
4 4.259 Butene isomer – – – √ – – – –
5 4.387 Butene isomer –√ –√ – √ – –√ – –
6 4.675 Ethanol – √ – – –
7 4.762 Isopropylethylene – – – √ – – – –
8 4.993 Iso-pentane – – – √ – – – –
9 5.100 Penta-1,4-diene –√ –√ –√ √ – –√ – –
10 5.273* Pent-1-ene √ √ √ – √ – –√
11 5.327 Acetone –√ √ – –
12 5.393* Pent-2-ene –√ – – – – –√
13 5.409 Isopropanol – –√ –√ – –√ – √
14 5.413* n-Pentane –√ –√ √ √ – √ √– √
15 5.677* Isoprene √ √ √ √ – √
16 5.797* Pent-2-ene √ √ – – –
17 5.912 Iso-pentene – – √ √ – – – –
18 6.118 Pentadiene – – √ – – – –
19 6.176 Methyl acetate – –√ –√ √ – – – –
20 6.456 Pentadiene – √ – – – –
21 6.514 Cyclopenta-1,3-diene – – – – –√ – –√
22 6.518 Unknown – – – –√ – –
23 7.025 Cyclopentene – – – √ – –√ – –√
24 7.041 Propan-1-ol – – –√ √ – –
25 7.351 2-Methylpent-2-ene – – √ – – – –
26 7.618 Methacrolein – – √ – – – –
27 7.623 2-Methylpenta-1,4-diene – – – √ – – – –
28 7.932 Propanenitrile – – – √ – – – –
29 7.994 3-Methylpentane –√ –√ – – –√ – –√
30 8.229 Acetic acid – – – √ – √
31 8.303 Unknown (m/z = 155) – – – –√ – –
32 8.286 Methyl vinyl ketone – – – √ – – – –
33 8.356 Hex-1-ene – – – √ – – – –
34 8.468 Butane-2,3-dione – – – √ – – – –
35 8.744 Methyl ethyl ketone –√ –√ –√ √ –√ –√ – –√
36 8.736* n-Hexane √ √ √ – √
37 9.053 Methylfuran – – √ √ – –
38 9.168 Methylpentene – – √ √ – – – –
39 9.407 Methylpentene –√ –√ – –√ – –√
40 9.483 Unknown –√ –√ – –
41 9.506 trans-2-Methylpenta-1,3-diene – – √ √ – – – –
42 9.630 Methylfuran – – √ √ – – – –
43 10.005 Methylpent-2-ene isomer – – √– – – –
44 10.018 Dimethyl carbonate – – –√ –√ – – –
45 10.434 Hexadiene – – √ √ – – – –
46 10.562 Isobutyronitrile – – √ – – – –
47 11.118 Hexadiene – – –√ √ – –√ – –√
48 11.407 Methyl-1,3-cyclopentadiene – – √ √ – √ – √
49 11.691 Methyl-1,3-cyclopentadiene – – √ √ – –
50 12.111 Methylcyclopentene – – √ √ – – – –
51 12.243 Methylcyclopentene – – √ √ – – – –
52 12.371 Crotonaldehyde – – √ – – – –
53 12.717 Isovaleraldehyde –√ –√ √ √– –√ –√ –√ –√
54 12.869* Benzene √
55 12.969 Unknown – – –√ – √ √– – –
56 12.270 2-Methylbutanal – – √ √– – –
57 13.385 Methyl-1,3-cyclopentadiene – – – – – –√
58 13.496 Branched heptane – – –√ – – – –
59 13.612 Methyl propenyl ketone –√ –√ – – –√ –√ –√
60 14.317* Isooctane –√ –√ –
61 14.374 Methyl propyl ketone – – √ √ – – – –
62 14.510 Hept-1-ene –√ –√ √ √ – –√ –√ –√
63 15.017* n-Heptane √ – √
64 15.046 Allyl methyl sulfide – – –√ – – –
65 15.170 Pentane-2,3-dione – – – √ – – – –
66 15.215 cis-3-Methylhex-2-ene – – –√ – – – –
67 15.252 Unknown – –√ √ √– – –√ – –√
68 15.524 2,5-Dimethylfuran – √ – –
69 16.687 Vinylfuran – – √ – – – – –
70 16.823 Hepta-1,5-diene – – √ –√ – – – –
71 17.231 3-Methylbutanenitrile – – – –√ – –
72 17.367 (E)-1-(Methylthio)prop-1-ene – – – – – – –
54 E.Marco,J.O.Grimalt/J.Chromatogr.A1410(2015)51–59

Table1(Continued)

N RT(min) Compound Nosmoking Tobacco e-cigaretteType1 e-cigaretteType2

Indoorair Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath
√ √
73 (17.5–23.5) Propylene glycol – – –√ –√ – –
74 17.544 Methyl propenyl ketone – – √ √ – – – –
75 17.566 1-Methyl-1H-pyrrole – – √ √ – – – –
76 17.705 1-Methyl-1,4-cyclohexadiene – – √ – – – –
77 18.039 Pyridine – – – √ – – – –
78 18.282 Pyrrole –√ –√ –√ √ – –√ –√ –√
79 19.263* Toluene √ √ – √ √
80 20.277 Unknown (m/z = 229, m/z = 73) –√ – – –
81 20.285 Oct-2-ene – – – – – – –

82 20.603 Cyclopentanone –√ –√ –√ –√ – –√ – –√
83 20.735* n-Octane √ – –
84 20.838 C12H22O –√ –√ √ √– –√ –√ – –√
85 21.180 Hexamethylcyclotrisiloxane √ –
86 21.555 Butyl acetate – – –√ – – – –
87 21.588 2,5-Dimethyl-2,4-hexadiene – – √ √– – – – –
88 21.876 Methylpyridine – – –√ – – –
89 22.116 C3H10N2 – – –√ –√ – – –
90 22.251 Methylpyrazine – – √ – – – –
91 22.396 Cresol isomer – – √ √– – – – –
92 22.643 Furfural – – √ √ – – – –
93 22.680 Cyclopentenone – – √ √ – – – –
94 23.138 2-Methylcyclopentanone –√ –√ √ √ –√ –√ – –√
95 24.044* Ethylbenzene √ √ –
96 24.127 Methylpyridine –√ –√ – –√ – –√
97 24.374 Unknown (m/z = 289) √ √ –√ –√ –√ √ –√ √
98 24.436* m-Xylene √ √ √ √ √ √ √ √
99 24.510* p-Xylene √ √
100 24.704 Unknown – – – – – √ –
101 25.215 1,2-Propanediol, 2-acetate – – – –√ – – –
102 25.236 1,6-Dimethylhepta-1,3,5-triene –√ –√ –√ √ – – – –
103 25.475 Styrene √ √ √ √ –√ –√ –√ –√
104 25.516* o-Xylene √
105 25.697 cis-2,6-Dimethyl-2,6-octadiene – – √ √– – – – –
106 25.990 2-Methyl-2-cyclopenten-1-one – – √ √ – – – –
107 27.313 3,4-Dimethyl-2-cyclopenten-1-one –√ –√ √ √– –√ –√ –√
108 28.117 Octamethylcyclotetrasiloxane –√ √
109 28.228 Limonene isomer – – √ √ – – – –
110 28.303 1-Ethyl-2-methylbenzene – – √ – – – –
111 28.509 1-Ethyl-3-methylbenzene – – – – –√ – –
112 28.500 Glycerin –√ –√ – –√ – √ – –√
113 28.587 Benzaldehyde √ √ – √ – √ – √
114 28.682 Phenol –√ √ – –
115 28.727 4-Ethenylpyridine – – –√ – –√ –
116 (29.5–34.5) Glycerin – – –√ –√ – –
117 29.139 (Z)-(cis-Geraniol) – – √ – – – –
118 29.444 Benzonitrile – – –√ – – – –
119 29.473 Unknown – – √ √– – – – –
120 29.692 Trimethylbenzene – – √ √ – – – –
121 29.716 Unknown –√ –√ – – – –
112223 2299..794811 O(cid:3)-cCtaanmaplhene – –√ –√ –√ –– –– –– ––
124 30.607 2-Ethylhexan-1-ol – √ √– –√ – – - –
112256 3300..798784 m(cid:3)--LCimymonenene e –√ √√ √ √ –– –√ –– –√
127 31.246 Eucalyptol – √– –√ – – – –
128 31.258 Ocimene – – √ – – – –
129 31.839 Indene –√ –√ – – – – –
130 32.470 Acetophenone √ √ – – – – – –
131 33.233 Nonanal √ √ – – – –√ – –√
132 33.331 Decamethylcyclopentasiloxane √ – – – –
133 33.509 Unknown –√ √ – – – – – –
134 34.428 Unknown √ √ – –√ –√ –√ – –√
135 34.551 Benzoic acid –√ –
136 35.203 2,3-Dimethylphenol – –√ –√ – –√ – –√
137 35.607 Decanal –√ –√ √ – –
138 35.809* Naphthalene – √ – – – –
139 36.332 2,3-Dihydrobenzofuran –√ –√ –√ – –√ – –√
140 36.435 Nonanoic acid √ √ – √ √– √ – √
141 36.773 Dodecamethylcyclohexasiloxane –√ –
142 37.791 Hydroquinone – – √ – – – – –
143 37.931 Unknown – – – – –√ – –
144 38.228 Decanoic acid – – –√ –√ –√ √ –√ –√
145 38.813* Nicotine – – √
146 39.702 Vanillin – – – – – – –
E.Marco,J.O.Grimalt/J.Chromatogr.A1410(2015)51–59 55

Table1(Continued)

N RT(min) Compound Nosmoking Tobacco e-cigaretteType1 e-cigaretteType2

Indoorair Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath
√
147 39.762 7-Methyl-1H-indole – – √– – –√ – –√
148 39.815 Tetradecamethylcycloheptasiloxane – – –√ –√ –
149 40.729 Myosmine – – – – –√ –
150 40.887 Ethyl vanillin – – –√ –√ –√ –√ √ –
151 41.641 Nicotyrine – – √ –
152 42.585 Dimethylaminocinnamonitrile – – –√ – √ – – –
153 43.723 Isonicoteine – – √– √– – –
154 43.888 Propanoicacid,2-methyl-,1-(1,1- – – – – – –

dimethylethyl)-2-methyl-1,3-
propanediyl
ester √
155 43.933 Hexadecamethylheptasiloxane – – – – √ – – –
156 44.424 Dimethylaminocinnamonitrile – – – – – – –

*Compoundsquantified.

3.2. Smokefromtobaccocigarettesande-cigarettes Inthisrespect,therelativeproportionofbenzeneandtoluenein

the samples described in this study, 44% and 56%, respectively,

RepresentativechromatogramsoftheVOCinthesmokecom- isinagreementwiththerelativeproportionofthesecompounds

positionoftobaccocigarettesandType1andType2e-cigarettes measuredinothertobaccosmokecigarettesmeasuredwithother

areshowninFig.2.Asexpectedastrongcontrastwasobserved samplingmethods,43%and57%,respectively[31].

betweentobaccocigaretteande-cigarettesmoke.Theformercon- Other compounds commonly related with traffic emissions

tained a wealth of compounds including nicotine and related werealsopresentinthetobaccocigarettesmokechromatogram,

productssuchasnicotyrine,7-methyl-1H-indole,myosmine,ison- e.g. n-heptane, n-octane, 1-ethyl-2-methylbenzene, 1-ethyl-3-

icoteine.Theoccurrenceofmyosmine,isonicoteineandnicotyrine methylbenzene and naphthalene. The occurrence of these com-

together with nicotine in tobacco cigarette smoke has been poundsintobaccocigarettesmokehasalsobeenreported[25,27].

reportedinpreviousstudies[24,25].2,5-dimethylfuranisanother In addition to these VOCs, many polar compounds were

compoundcharacteristicoftobaccocigarettesmokethathasbeen also represented in the tobacco cigarette smoke chromatogram,

proposed as a specific marker [25–29]. In the present study, e.g. ethanol, acetone, acetic acid, butane-2,3-dione, methyl ethyl

thiscompoundwaspresentinthechromatogramofthetobacco ketone,methylfuran,isovaleraldehyde,pyridine,methylpyridine,

cigarettesmokeandabsentinthoseofthee-cigarettesmoke(Fig.2; benzaldehyde, phenol, benzonitrile, acetophenone. These com-

Table1). poundshavealsobeenfoundintobaccocigarettesmokeinprevious

Besidesthesespecificcompoundsseveralaromaticcompounds studies [7,25,26,30,32]. Some aldehydes such as crotonaldehyde

suchasbenzene,toluene,xylenes,ethylbenzeneandstyrenewere arealsoidentifiedwiththismethod.Thiscompoundhasalsobeen

alsofoundinthechromatogramoftobaccocigarettesmoke(Fig.2). found in tobacco cigarette smoke in analyses using the dinitro-

Thesecompoundsarenotspecificfortobaccocigarettesmoke,as phenylhydrazinemethod[33].

severalofthemarefoundintheBTEXmixturesassociatedtotraffic Chromatographic peaks for several unsaturated compounds

emissions.However,asdocumentedelsewhere[25–27,30,31],ben- were also found in the tobacco cigarette smoke sample, such as
zene,akno wncarcin og en,iscommo nintobac cocigarettesm oke. buta- 1,3-d iene, i sop ren e, hex-1 -ene, hep -1-ene and (cid:3)-lim onen e.

Fig.1. Chromatogramsshowingthecompositionofvolatileorganiccompoundsinairfromanin-doorenvironmentandexhaledbreathofavolunteerpresentinthis

environmentwithoutsmoking.
56 E.Marco,J.O.Grimalt/J.Chromatogr.A1410(2015)51–59

Fig.2. Chromatogramsshowingthecompositionofvolatileorganiccompoundsinsmokefromtobaccocigarettes,Type1andType2e-cigarettesandinexhaledbreathof

smokers.Toavoidmetabolicdifferencesalldisplayedexhaledbreathchromatogramscorrespondtothesamevolunteer.

Severalofthemareknownnaturalproductsthatcanalsobefound (Fig.2)indicatingthatmostoftheoriginalsmokecomponentswere

inmanyplantspecies.Theirpresenceintobaccocigarettesmokeis retained in the lungs. Thus, the relative intensity of most of the

consistentwithpreviousstudies[7,25,27,30]. higher molecular weight VOCs, those of higher chromatographic

Theanalyticalapproachofthepresentstudyhasbeendesigned retentiontime,decreasedsignificantly.However,somecompounds

for the identification and quantification of the volatile com- thatarespecificoftobaccocigarettesmokesuchasnicotine,nico-

pounds. However, some compounds found in the present study tyrine and 2,5-dimethylfuran were found in the exhaled breath.

(Table 1) have also been identified in the particulate phase TheiroccurrenceintheVOCcompositioncanbeusedtoindicate

in analytical methods specifically designed for the compounds theexposureoftheindividualstotobaccosmokecompounds.Other
pr esentinth isphase,e .g.aceticac id,crotona lde hyde ,n-heptane, VOC ssuchas be nze ne,toluene o r(cid:3)-limo nenew erelessspec ificof
phenol, (cid:3)- limo nene, ben zoic a cid, hydroquinone, n icotine, 7- tobac cocig ar ettesmok ebutth ey stillweredo mina ntpe aksint he

methyl-1H-indole,myosmineandnicotine[23].Thesecompounds exhaledbreathchromatogramsofthetobaccocigarettesmokers.

are generally polar and formed by pyrolysis or distillation of Isoprene was the most abundant exhaled breath peak. As men-

the tobacco components under the high temperature conditions tionedabove,thisisanendogenouscompound.

of smoking. Condensation processes lead to their distribution In the exhaled breath of the e-cigarette smokers the chro-

betweenthegasandparticulatephases. matographicpeaksofpropyleneglycolandglycerinwereabsent

In contrast, the smoke of the e-cigarettes was mainly com- indicating that they remained in the respiratory system of the

posed of propylene glycol and glycerin which is consistent with smokers. Comparison of both original e-cigarette smoke and

theproductdescriptionofthemanufacturers(notethatthechro- exhaled breath of the e-cigarette smokers also showed a strong

matographicpeaksareoverloaded).Inadditionthesmokeofthe decreaseofthepeakscorrespondingtonicotineandrelatedcom-

e-cigarettescontainednicotineandrelatedproductssuchasmios- pounds.Ontheotherhand,twomainpeaksinthechromatograms

mineandnicotyrine.ThesmokeofType2e-cigarettealsocontained from exhaled breath were those corresponding to acetone and

vanillinandethylvanillinwhichwerelikelyaddedasaflavor. isoprenewhichlikelyrepresentendogenoussources.Inaddition,

benzene, toluene and 2,5-dimethylfuran were also found. These

peaks were below limit of detection in the e-cigarette smoke
3.3. Exhaledbreathfromtobaccocigaretteande-cigaretteusers vapors .Thei roccurr encei ne xhaledbre ath coul dreflectpas texpo-

suresofthevolunteers.
Representative chromatograms of the VOCs in the exhaled

breathoftobaccocigaretteandType1andType2e-cigaretteusers 3.4. Figuresofmerit

are shown in Fig. 2. The chromatogram of exhaled breath of a

tobaccocigarettesmokershowedasimplifiedmixtureofthecom- Linear concentration ranges over three magnitudes of con-

poundsfoundinthepreviouslydescribedsmokeofthesecigarettes centration were found for most compounds analyzed (Table 2).
E.Marco,J.O.Grimalt/J.Chromatogr.A1410(2015)51–59 57

Table2

Figuresofmerit.

Compound Rangea(ng) R2 RSDb(%) LODc(ng) Bio-VOC

Meand(ng) Repeatability(RSD%) Recovery(%)

Pent-1-ene 0.5–10 0.9962 7.1 0.17 10.4 17.7 94

10–250 0.9971

n-Pentane 0.25–10 0.9997 5.5 0.05 12.6 22.7 109

10–250 0.9971
Pent-2-ene 0.5–10 0.9984 4.7 0.12 11.8 18.1 103

10–250 0.9966

Isoprene 0.25–10 0.9982 4.5 0.11 10.7 19.3 92

10–250 0.9969

Pent-2-ene 0.25–10 0.9994 4.1 0.06 11.1 18.6 97

10–250 0.9966
n-Hexane 1–30 0.9977 4.5 0.43 11.5 17.6 89

30–250 0.9965

Benzene 0.25–10 0.9962 3.5 0.16 13.6 12.4 99

10–250 0.9955

Isooctane 0.6–26 0.9996 3.1 0.13 37.5 13.8 114

26–260 0.9977

n-Heptane 0.5–10 0.9983 3.2 0.11 22.4 14.8 96

10–470 0.9920

Toluene 1–25 0.9989 6.1 0.65 12.8 18.3 110

25–250 0.9812

n-Octane 0.5–10 0.9977 4.8 0.13 23.6 11.2 96

10–200 0.9975

Ethylbenzene 0.25–5 0.9987 4.0 0.05 11.5 6.5 92

5–100 0.9990

m-Xylene 0.25–5 0.9965 3.2 0.08 11.4 7.5 92

5–100 0.9988
p-Xylene 0.25–5 0.9979 4.5 0.06 11.3 5.9 97

5–100 0.9983

o-Xylene 0.25–5 0.9987 4.1 0.05 11.4 6.1 94

5–100 0.9987

Naphthalene 0.25–5 0.9978 6.3 0.06 10.6 8.5 92

5–50 0.9989

a Amountintroducedintothecartridges.
b Residual standardd eviat ion ofthecalibrationlines.
c Limitsof detection .
d Meanv al uesofreplicateanalysesforcalculationofrepeatabilityandrecovery.

In some cases, e.g. n-hexane, naphthalene, these ranges were 2.2. The highest limits, e.g. toluene (0.65ng), were due to back-

about 200. The limits of detection ranged between 0.05 and groundatmosphericlevelsbyuseofthiscompoundinnearbylabs.

0.65ng.Thetransformationoftheselimitsintoconcentrationval- Repeatability (residual standard deviation of ten measurements)
ues ( (cid:2)g /m3) must be done by refer ence t o th e sampled volu me ranged betwe en 5.9 an d 23% w hich is co nsi sten t with previous

that depends on the number of Bio-VOC replicates (N). Thus, measurements with Bio-VOCs in other studies [11]. Recover-

amountdetectionlimit(ng)isequivalenttoconcentrationdetec- ies of standards introduced into the Bio-VOCs and analyzed as
tionlimi t((cid:2)g/m3) when mul tip lyingthefo rm erby1000/(15 0×N). des cri bedinthee xperimenta lsect ionr angedbetw een 92and11 4%

The number of replicates in the analyses is indicated in section (Table2).

Table3
Conce ntrations((cid:2)g/m3)ofselectedVOCinair,smokeandexhaledbreatha.

Nosmoking Tobaccocigarettesmoking Type1e-cigarettesmoking Type2e-cigarettesmoking

Compound Indoorair Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath Smoke Exhaledbreath

Pent-1-ene 0.5 0.6 700 68 nd 0.3 nd nd

n-Pentane nd nd 1200 63 nd 7 nd nd

Pent-2-ene nd 0.5 625 52 nd 0.3 nd nd

Isoprene 0.4 87 2700 670 nd 47 nd 45

Pent-2-ene nd 0.3 460 32 nd 0.2 nd nd

n-Hexane 1 nd 975 14 nd nd nd 0.6

Benzene 0.6 4 1100 49 0.6 0.8 nd 0.5

Isooctane 0.4 0.2 nd nd nd 0.2 nd 1.5

n-Heptane 0.2 0.4 890 26 nd 0.3 1 2.1

Toluene 5 11 1400 60 nd 3 4 6.4

n-Octane nd 0.2 560 3 nd nd nd nd

Ethylbenzene 0.2 0.6 660 6 1 0.2 nd 0.3

m-Xylene 0.2 0.5 980 7 nd 0.2 nd 0.2

p-Xylene 0.1 0.2 420 2 0.6 0.1 nd 0.1

o-Xylene 0.1 0.2 590 2 0.4 0.1 nd 0.1

Naphthalene 0.05 0.1 240 3 nd nd nd nd

Nicotine nd nd 1300 7 720 4 710 1

a Allcompoundswerequantifiedwithauthenticstandardsexceptnicotinethatwasquantifiedwithnaphthalene.
58 E.Marco,J.O.Grimalt/J.Chromatogr.A1410(2015)51–59

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