E-luam yeeb pov tseg thiab muaj feem cuam tshuam txog kev noj qab haus huv: Kev Tshawb Fawb Kev Tshawb Fawb
Tso lus
E-luam yeeb pov tseg thiab muaj feem cuam tshuam txog kev noj qab haus huv: Kev Tshawb Fawb Kev Tshawb Fawb
Abstract
Kev siv cov tshuab xa hluav taws xob nicotine (ENDS), suav nrog cov luam yeeb e-luam yeeb, tau tshwm sim. Cov tshuaj ntsuam xyuas uas twb muaj lawm ntawm ENDS tau tsom mus rau e-kua ntau dua li aerosols thiab ua tsis tiav los txiav txim siab qhov loj me thiab aerosol respiratory deposition fractions, uas yog qhov tseem ceeb rau kev nqus cov tshuaj. Txoj kev tshawb no tshawb xyuas cov organic tshuaj thiab cov khoom siv hlau hauv qhov loj-segregated ENDS aerosol thiab tshuaj xyuas cov koob tshuaj thiab kev noj qab haus huv ntawm cov tshuaj no. Kev tshuaj xyuas tshuaj aerosol tau ua rau ob yam khoom siv ENDS nrov: Puff Bar (Grape) thiab Air Bar (Ice Watermelon Ice). Ib qho ENDS aerosol tau tsim thiab xa mus rau Micro-Orifice Uniform Deposit Impactor los sau cov qauv me me-segregated aerosol, uas cov tshuaj organic thiab hlau tau tshuaj xyuas. Cov koob tshuaj txhua hnub thiab lub neej rau txhua yam tshuaj tau kwv yees. Kev ntsuam xyuas mob qog noj ntshav thiab tsis yog mob qog noj ntshav tau ua raws li cov koob tshuaj tso tseg. Peb pom tias e-luam yeeb aerosol muaj qee yam tshuaj lom neeg cov tshuaj lom neeg thiab cov hlau uas tau sau tseg ua rau muaj teeb meem ua pa. Kev kwv yees kev pheej hmoo ntawm kev mob qog noj ntshav ua pa cuam tshuam nrog chromium los ntawm ob qho tib si ENDS cov khoom lag luam thiab npib tsib xee los ntawm Cua Bar (Watermelon Ice) yog qhov tseem ceeb tshaj qhov kev pheej hmoo txaus ntshai. Cov txheej txheem, kev tshawb pom, thiab kev cuam tshuam tuaj yeem ua rau muaj cov ntaub ntawv txuas ntxiv ntawm ENDS cov kev tshawb fawb txog tshuaj lom thiab qhia txog kev cai luam yeeb thiab kev tshawb fawb loj yav tom ntej.
Ntsiab lus:
e-luam yeeb pov tseg; aerosol toxicity; kev noj qab haus huv txaus ntshai; particle loj faib; ua pa deposition1. Taw qhia
Kev siv hluav taws xob nicotine xa tuaj (ENDS), suav nrog kev siv e-luam yeeb, muaj ntau ntawm cov hluas thiab cov hluas thiab tau dhau los ua teeb meem kev noj qab haus huv rau pej xeem. Raws li peb qhov kev soj ntsuam thib ob ntawm 2019 National Health Interview Survey cov ntaub ntawv, qhov feem ntau ntawm kev siv ib txwm siv thiab tam sim no siv ENDS ntawm cov tub ntxhais hluas yog 32.4% thiab 9.4%, feem, raws li kev nce ntxiv hauv kaum xyoo dhau los [1]. Ntxiv mus, kev tshawb fawb siv cov ntaub ntawv los ntawm 2019 National Youth Tobacco Survey qhia tias 27.5% ntawm cov tub ntxhais kawm theem siab qhia txog kev siv e-luam yeeb tam sim no; ntawm lawv, 34.2% qhia txog kev siv e-luam yeeb ntau zaus (piv txwv li, siv 20 lossis ntau dua hnub hauv 30 hnub dhau los) [2]. ENDS cov khoom lag luam tshwj xeeb yog txaus siab rau cov tub ntxhais hluas thiab cov tub ntxhais hluas vim lawv cov kev hloov kho thiab cov yam ntxwv tshiab [3,4,5], qis dua kev pheej hmoo [6,7], thiab muaj kev lees paub ntau dua li cov luam yeeb [8].
ENDS cov khoom muaj ntau haiv neeg thiab tau hloov zuj zus los ntawm cov khoom siv luam yeeb zoo li cov khoom siv pov tseg (thawj tiam) rau cov tshuab cartridge ( tiam thib ob), rau lub tshuab tank ( tiam thib peb), thiab rau cov khoom siv ntsev nicotine xws li JUUL (tiam plaub). Tsis ntev los no, qhov nrov ntawm JUUL tau ntes tau los ntawm JUUL zoo li cov khoom siv pov tseg e-luam yeeb (tom qab no, "tso tseg ENDS") vim lawv cov kev xaiv flavoring, qhov muag pom kev tsim thiab ntim khoom, tus nqi qis, thiab kev yooj yim (piv txwv li, tag nrho- nyob rau hauv-ib, nws tus kheej-muaj, tsis muaj filling ntawm e-kua thiab tsis muaj roj teeb them) [2,9]. Kev lag luam luam yeeb tau pom qhov muaj txiaj ntsig zoo tshaj plaws hauv kev muab cov khoom tshiab / hloov kho raws li cov cai [10]. Piv txwv li, thaum txoj kev tshawb no tau ua thaum ntxov 2022, cov khoom siv ENDS pov tseg tsis txwv los ntawm tsoomfwv cov cai tswjfwm vim yog FDA lub ntsiab lus nqaim ntawm daim cartridge [11]. Qhov tseeb, 85.8% ntawm cov tub ntxhais hluas cov neeg siv tam sim no yuav ENDS pov tseg nrog txiv hmab txiv ntoo flavour [12].
Cov kev tshawb fawb tau pom tias ENDS cov khoom muaj cov tshuaj tsw qab, uas qee qhov cuam tshuam nrog kev ua pa ua pa lossis ua rau mob, xws li δ-dodecalactone, menthol, benzyl cawv, thiab corylon [13,14,15,16]. Tsis tas li ntawd, cov khoom cua sov (xws li, atomizer / coil) thiab cov tso tsheb hlau luam ntawm ENDS cov cuab yeej muaj cov hlau uas tuaj yeem tso tawm rau hauv e-kua thiab aerosol thaum siv, nrog chromium thiab npib tsib xee yog cov ua rau muaj kev pheej hmoo mob qog noj ntshav [17,18]. Txawm li cas los xij, kev tshuaj ntsuam tshuaj uas twb muaj lawm tau ua rau ENDS cov khoom, suav nrog ENDS pov tseg, feem ntau tsom rau e-kua uas tsis tas yuav cuam tshuam cov tshuaj hauv ENDS aerosol uas tau tso rau hauv ENDS cov neeg siv 'airways [15,19]. Txawm hais tias muaj qee qhov kev tshawb fawb uas tau txheeb xyuas ENDS aerosol [20,21,22] thiab ntsuas qhov cuam tshuam txog kev noj qab haus huv [18], cov kev tshawb fawb no ua tsis tiav los txiav txim siab qhov loj me ntawm ENDS aerosol thiab qhov loj me ntsig txog kev ua pa. deposition fractions thaum kwv yees cov kev pheej hmoo ntawm kev noj qab haus huv. Qhov no yog ib qho teeb meem loj heev vim qhov loj ntawm cov khoom ncaj qha cuam tshuam rau qhov chaw ua pa tso pa tawm thiab cov seem hauv cov pa. Qhov tseeb, ENDS aerosol generated los ntawm vaping yog ib qho kev sib xyaw ntawm cov kua tee nrog cov aerosol particle txoj kab uas hla xws li ultrafine (tsawg dua 0.1 µm) mus rau micron qhov ntau thiab tsawg (txog li 4 µm). Yog li, nqus tau ENDS aerosol yuav tsum nkag mus thiab tso rau hauv thaj chaw sib txawv ntawm tib neeg txoj kev ua pa nrog ntau cov tshuaj tso tseg. Qhov tseem ceeb, nws xav tias feem ntau ntawm ENDS aerosol yuav tso rau hauv qhov ua pa qis, yuav ua rau muaj kev cuam tshuam tsis zoo rau kev noj qab haus huv vim tias thaj chaw ua pa loj hauv cheeb tsam alveolar [23]. Cov koob tshuaj tso tawm yog qhov ua ntej ntawm cov koob tshuaj sab hauv ua ntej kev txiav txim siab ntawm kev ua pa tshem tawm thiab qhov nqus nqus thiab yog li tuaj yeem ua tus pivot Performance index ntawm vaping-koom nrog kev ntsuas kev noj qab haus huv. Lub ENDS aerosol loj faib thiab ua pa deposition fractions yog lub ntsiab yam tseem ceeb rau kev kwv yees qhov pivot index [23], thiab yog li nws yuav tsum tau muab tso rau hauv kev soj ntsuam kev pheej hmoo ntawm kev noj qab haus huv.
Txoj kev tshawb no tau sau cov kev paub dhau los los ntawm kev siv txoj hauv kev txhim kho los kwv yees cov tshuaj tso tawm ntawm cov tshuaj nyob rau hauv ob feem ntau siv cov khoom siv ENDS thiab lawv cov mob qog noj ntshav thiab tsis mob qog noj ntshav. Txoj kev sim tau txiav txim siab qhov loj-dependent aerosol respiratory deposition fractions thiab ua qhov loj-segregated chemical constituent tsom xam ntawm ENDS aerosol. Kev tshawb nrhiav los ntawm peb txoj kev tshawb fawb tuaj yeem txhim kho qhov tseeb ntawm kev kwv yees cov tshuaj ENDS tso rau hauv lub ntsws vaper, uas tuaj yeem qhia txog kev cai luam yeeb thiab kev tshawb fawb loj yav tom ntej uas ntsuas kev noj qab haus huv cuam tshuam nrog kev siv ENDS cov khoom siv pov tseg.
2. Cov ntaub ntawv thiab cov txheej txheem
2.1. Loj-Segregated ENDS Aerosol Sample Collection
Kev tshuaj xyuas tshuaj Aerosol hauv txoj kev tshawb no tau ua los ntawm ob yam khoom siv ENDS nrov hauv qab no: Puff Bar (Grape) thiab Air Bar (Ice Watermelon Ice). Kev xaiv ntawm ob qho khoom siv ENDS pov tseg no yog ua raws li qhov ntau ntawm cov khoom siv ENDS pov tseg los ntawm kev tshawb fawb cais los ntawm pab pawg tshawb fawb uas tau tshuaj xyuas cov tub ntxhais kawm qib siab 'ENDS siv tus cwj pwm. Ob qhov khoom siv ENDS pov tseg no yog cov uas tau txais kev pom zoo tshaj plaws ntawm cov neeg koom nrog kev kawm.
Hauv txoj kev tshawb no, qhov loj-segregated ENDS aerosol cov qauv tau sau los ntawm kev siv Micro-Orifice Uniform Deposit Impactor (MOUDI 110-R, MSP Co., Shoreview, MN, USA). MOUDI muaj peev xwm sau tau cov qauv aerosol nrog particle diameters li ntawm 0.056 mus rau 18 µm nyob rau hauv nws 11 theem sau (ie, loj-segregated sampling). Nws ua tau zoo tshaj qhov kev nyeem ncaj qha aerosol cov twj paj nruag xws li particle counters thiab spectrometers uas tsis tuaj yeem kov cov e-luam yeeb aerosol tshiab nrog cov aerosol siab heev. Txhua theem MOUDI muaj qhov sib sau ua ke qhov loj me, thiab qhov nruab nrab ntawm lub ntsws tso tawm feem yuav raug xam raws li qhov loj me me (saib Daim Ntawv Ntxiv A Table A1). ENDS cov qauv aerosol sau los ntawm MOUDI nyob rau hauv ntau theem tau siv rau particle loj faib xam thiab tshuaj ntsuam xyuas muaj pes tsawg leeg.
Txhawm rau sau cov qauv ENDS pov tseg aerosol, polytetrafluoroethylene (PTFE) membrane lim (PALL Co., Port Washington, NY, USA) tau muab tso rau ntawm txhua theem MOUDI, thiab MOUDI tau ua haujlwm ntawm 30 L / min sampling flow rate. Ib lub 100 mL syringe tau siv los kos ENDS aerosol los ntawm ob cov khoom siv ENDS pov tseg thiab tom qab ntawd tso cov ENDS aerosol ncaj qha rau hauv MOUDI rau cov qauv sau. Cov txheej txheem no tau rov ua dua 10 zaug (10 puffs) kom ua tau ntau ntawm qhov xaus aerosol ntawm txhua lub cev Moudi rau qhov hnyav ntawm qhov hnyav thiab tshuaj yeeb tshuaj. Tom qab kev sim sau cov qauv, PTFE cov ntxaij lim dej nrog cov qauv ENDS aerosol tau muab tshem tawm los ntawm MOUDI, ib tus zuj zus hnyav los ntawm microbalance, thiab tom qab ntawd xa mus rau cov chaw kuaj xyuas cov tshuaj lom neeg cov tshuaj lom neeg thiab tshuaj ntsuam hlau txhawm rau txheeb xyuas qhov loj me ntawm cov tshuaj lom neeg hauv ENDS aerosol. Cov qauv sau tau ua peb zaug rau txhua qhov khoom ENDS kom ntseeg tau cov ntaub ntawv kev ntseeg siab thiab rov ua dua. Lub ENDS aerosol particle loj faib thiab cov ntaub ntawv loj-dependent tshuaj lom neeg cov ntaub ntawv ua lub luag haujlwm tseem ceeb hauv kev kwv yees cov koob tshuaj ntawm cov tshuaj ENDS tshwj xeeb hauv lub ntsws vaper.
2.2. Organic Chemical thiab Metal Analysis
Cov tshuaj lom neeg tshuaj ntsuam xyuas rau ENDS aerosol tau ua los ntawm kev siv roj chromatography-mass spectrometry (GC/MS) txhawm rau txheeb xyuas cov khoom siv tshuaj lom neeg xws li nicotine, PG, VG, thiab cov tshuaj tsw qab ntawm MOUDI lim kom tau txais cov ntaub ntawv loj-nyob ntawm seb. Tshwj xeeb, ob qhov ENDS pov tseg tau muab tshem tawm los nrhiav cov e-kua-soaked vaping wicks. Cov tshuaj tseem ceeb hauv e-kua yog thawj zaug muab rho tawm nrog acetonitrile thiab tshuaj xyuas los ntawm GC / MS. Tom qab ntawd, ENDS aerosol cov qauv ntawm MOUDI cov ntxaij lim dej tau muab rho tawm tib yam thiab tsom rau GC / MS tsom xam. GC / MS tshuaj ntsuam xyuas tau nruab nrog ib qho khoom siv hluav taws xob ionization ion (GC / EI-MS, Agilent 6890N GC, thiab 5975 inert XL MSD), thiab cov tshuaj tau txheeb xyuas tag nrho siv cov qauv tseeb lossis tus qauv tsim. Cov txheej txheem ntxaws ntxaws rau kev txheeb xyuas cov organic tau piav qhia lwm qhov [23]. Hauv kev tshuaj ntsuam xyuas cov organic, qhov kev rov qab los ntawm cov phiaj xwm tsom xam tau txiav txim siab los ntawm spiking ib qho kev paub ntawm cov tshuaj mus rau cov lim dej dawb (n=3) thiab muab rho tawm nrog tib cov txheej txheem xws li sau cov qauv aerosol. Kev soj ntsuam hlau tau ua los ntawm kev siv Inductively Coupled Plasma Mass Spectrometry (ICP / MS) txhawm rau txheeb xyuas qhov loj ntawm cov hlau phom sij xws li npib tsib xee, chromium, thiab txhuas ntawm MOUDI lim sib txawv kom tau txais cov ntaub ntawv loj-nyob ntawm seb. MOUDI cov ntxaij lim dej tau ua tiav thawj zaug rau cov kua qaub kua qaub thiab kev zom zaub mov siv ultra-huv ob chav distilled HNO3thiab HF, thiab tom qab ntawd cov qauv kev daws teeb meem tau evaporated rau incipient dryness. Cov txheej txheem tsim tau zoo yav dhau los tau ua raws li ICP/MS tsom xam siv ICP/MS Triple Quad (Model 8800, Agilent Technologies, Santa Clara, CA, USA) [24]. Nyob rau hauv txoj kev no, cov ntsiab lus hlau mus rau sub-ppb (ng / g) qib nrog ± 5% ntawm qhov tseeb tuaj yeem tau txais.
Lub hom phiaj ntawm kev soj ntsuam kuaj hauv qhov kev tshawb fawb no yog cov tshuaj lom neeg tsis zoo thiab cov hlau uas tau txheeb xyuas yav dhau los hauv ENDS aerosol thiab luam tawm hauv cov ntaub ntawv [14,18,25,26,27,28,29]. Yog li ntawd, qhov tsim ntawm peb cov organic tshuaj tsom xam yog tsom rau nicotine, carrier hnyav (piv txwv li, glycerol, propylene glycol, formaldehyde, acetaldehyde, acrolein, acetone, methylglyoxal, benzoic acid, thiab triethyl citrate), nrog rau flavoring thiab lwm yam tshuaj ( xws li, Ethennin, cinnamin, cinnamaldehyde, menzaldehyde, Methyl actharate, ethyl ethylitone, ethyl actharan, δ-dodecalactone, -terpineol, -decalactone, thiab 3-hexen-1-ol). Los ntawm tib lub cim, ntau dua 20 cov hlau tau kuaj pom hauv peb cov kev ntsuam xyuas hlau, tab sis qhov tseem ceeb ntawm txoj kev tshawb no yog nyob rau ntawm nickel (Ni), manganese (Mn), zinc (Zn), chromium (Cr), thiab lead (Pb).
2.3. Kev kwv yees Deposited Doses ntawm ENDS Tshuaj
Txhawm rau kwv yees cov kev pheej hmoo ntawm kev noj qab haus huv cuam tshuam nrog kev nqus ntawm ENDS cov tshuaj hauv lub ntsws vapers, qhov nruab nrab koob tshuaj txhua hnub (ADD) thiab lub neej nruab nrab koob tshuaj txhua hnub (LADD) raug xam. ADD thiab LADD raug xam raws li cov qauv sib npaug hauv qab no:𝐴𝐷𝐷=𝐶×𝐶𝑅×𝐶𝑇𝐵𝑊×𝐴𝑇���=�×��×����×��
(1)
𝐿𝐴𝐷𝐷=𝐶×𝐶𝑅×𝐶𝑇𝐵𝑊×𝐿𝐸����=�×��×����×��
(2)
nyob qhov twg 𝐶 � yog qhov nthuav tawm (ng / m3), 𝐶𝑅�� yog tus nqi sib cuag (m3/ hnub), 𝐶𝑇�� yog lub sijhawm sib cuag, uas yog kwv yees li 30 xyoo (10,950 hnub) rau cov neeg vaper siab, 𝐵𝑊�� yog lub cev hnyav (70 kg), 𝐴𝑇�� yog lub sijhawm nruab nrab , uas sib npaug rau 𝐶𝑇�� (10,950 hnub), thiab 𝐿𝐸�� yog lub neej expectancy, uas yog 70 xyoo (25,550 hnub) raws li USEPA default exposure assumpions. Nyob rau hauv cov ntaub ntawv ntawm vaping, lub sij hawm 𝐶×𝐶𝑅�×�� yog sib npaug rau txhua hnub noj ntawm ENDS cov khoom (ng / hnub), thiab cov khoom noj txhua hnub los ntawm vaping yuav tsum yog los ntawm tag nrho cov puffs ntawm vaping nyob rau hauv ib qho. hnub. Raws li cov ntaub ntawv, qhov tshaj tawm qhov nruab nrab txhua hnub puffs ntawm vaper yog nyob ib ncig ntawm 163 puffs / hnub [30]. Yog li, raws li kev sim tsim thiab cov txiaj ntsig ntawm qhov kev tshawb fawb no, Kev sib npaug (1) thiab (2) tuaj yeem hloov kho rau qhov chaw vaping raws li hauv qab no:𝐴𝐷𝐷𝑗=∑𝑖𝐴𝐷𝐷𝑖,𝑗=0.1𝑀𝑖,𝑗×𝐶𝑅𝑝×𝐶𝑇𝐵𝑊×𝐴𝑇����=∑�����,�=0.1��,�×���×����×��
(3)
𝐿𝐴𝐷𝐷𝑗=∑𝑖𝐿𝐴𝐷𝐷𝑖,𝑗=0.1𝑀𝑖,𝑗×𝐶𝑅𝑝×𝐶𝑇𝐵𝑊×𝐿𝐸�����=∑������,�=0.1��,�×���×����×��
(4)
qhov twg 𝑀𝑖,𝑗��,� yog qhov loj ntawm ib qho tshwj xeeb ENDS tshuaj j (organic chemical lossis hlau) hauv ENDS aerosol pom nyob rau ntawm MOUDI theem I (i {{0}}} rau 11) los ntawm GC / MS thiab ICP / MS analyses. Txij li thaum 𝑀𝑖,𝑗��,� yog raws li 10 puffs, 0.1𝑀𝑖,𝑗��, � yog sib npaug rau qhov loj ntawm ENDS cov khoom hauv ib lub puff. 𝐶𝑅𝑝��� yog ENDS aerosol tus nqi sib cuag hauv chav tsev ntawm puff / hnub. Raws li cov ntaub ntawv, 𝐶𝑅𝑝��� tau teem rau 163 puffs / hnub [30]. Raws li cov no, 𝐴𝐷𝐷𝑖, 𝑗����, � qhia txog qhov nruab nrab txhua hnub koob tshuaj ntawm ib yam khoom j muaj nyob rau hauv ENDS aerosol nyob rau hauv ib tug loj ntau yam i (MOUDI theem i); 𝐿𝐴𝐷𝐷𝑖, 𝑗�����,� yog lub neej nruab nrab txhua hnub koob tshuaj j muaj nyob rau hauv ENDS aerosol nyob rau hauv ib tug loj ntau yam i. Qhov kev xam pom hauv Equations (3) thiab (4) qhia tias koob tshuaj ENDS tshwj xeeb hauv lub ntsws ua haujlwm vaper yog xam los ntawm kev sib sau cov koob tshuaj los ntawm tag nrho 11 tus neeg MOUDI theem (∑𝐴𝐷𝐷𝑖,𝑗∑������,� thiab ∑𝐿𝐴𝐷𝐷𝑖, 𝑗∑�����,�) Qhov sib npaug (3) thiab (4) tuaj yeem hloov kho ntxiv los ntawm kev xav txog qhov tseem ceeb ntawm aerosol respiratory deposition fractions los kwv yees cov koob tshuaj tso rau hauv vaper lub ntsws (piv txwv li, koob tshuaj. pab txhawb los ntawm ENDS aerosol uas tau tso rau hauv cov hlab cua) raws li hauv qab no:𝐴𝐷𝐷′𝑗=∑𝑖𝐴𝐷𝐷𝑖,𝑗×𝐷𝐹𝑖���′�=∑�����,�×���
(5)
𝐿𝐴𝐷𝐷′𝑗=∑𝑖𝐿𝐴𝐷𝐷𝑖,𝑗×𝐷𝐹𝑖����′�=∑������,�×���
(6)
qhov twg 𝐷𝐹𝑖��� yog qhov nruab nrab ntawm cov pa tso pa tawm feem (ntawm {{0}}}0 txog 1.0) rau qhov sib sau aerosol loj ntawm MOUDI theem i. Tib neeg txoj kev ua pa uas siv rau hauv txoj kev tshawb no suav nrog tracheobronchial airways mus rau thaj tsam alveolar, thiab cov ntaub ntawv luam tawm ntawm aerosol respiratory deposition fractions tau txais los ua kom tau txais qhov nruab nrab deposition feem (saib Cov Ntawv Ntxiv A Table A1 rau qhov kwv yees 𝐷𝐹) 23] ib. Nyob rau hauv txoj kev no, 𝐴𝐷𝐷′𝑗���'� thiab 𝐿𝐴𝐷𝐷′𝑗����'� coj mus rau hauv tus account qhov tseeb qhov loj me-nyob ntawm qhov loj ntawm cov khoom hauv ENDS aerosol nrog rau cov feem ntawm qhov nqus tau ENDS aerosol uas muaj nyob hauv. mus rau qhov tso tshuaj.2.4. Kev kwv yees kev mob qog noj ntshav thiab tsis mob qog noj ntshav
Qhov kwv yees 𝐴𝐷𝐷′𝑗���'� los ntawm Equation (5) yog siv los xam qhov phom sij (HQ) rau kev ntsuam xyuas qhov tsis mob qog noj ntshav uas tshwm sim los ntawm cov tshuaj j hauv cov khoom siv pov tseg ENDS (organic chemical lossis hlau) raws li nram no:𝐻𝑄𝑗=𝐴𝐷𝐷′𝑗𝑅𝑓𝐷𝑗 {<1 No adverse health effect is expected>1 Kev noj qab haus huv tsis zoo yog qhov muaj peev xwm ���=���'����� {<1 No adverse health effect is expected>1 Kev noj qab haus huv tsis zoo yog qhov muaj peev xwm
(7)
qhov twg 𝑅𝑓𝐷𝑗���� yog cov tshuaj siv (RfD) luam tawm rau ENDS cov khoom j. Nco ntsoov tias nyob rau hauv rooj plaub uas tsuas yog siv cov concentration (RfC) muaj rau ib yam khoom, RfC tau hloov mus rau RfD siv qhov tsim nyog inhalation ntawm 20 m.3/ hnub thiab lub cev hnyav ntawm 70 kg (ie, RfD=RfC × 20/70) [18]. Tsis tas li ntawd, qhov kev ntsuas phom sij (HI) tau siv rau cov tshuaj, uas ua rau muaj kev cuam tshuam zoo sib xws uas tsis yog mob qog noj ntshav rau tib lub hom phiaj ntawm lub cev / lub cev (piv txwv li, ua pa). Yog li ntawd, HI yog cov ntsiab lus ntawm txhua yam ntsig txog 𝐻𝑄𝑗��� (𝐻𝐼=∑𝐻𝑄𝑗��=∑���). Thaum HQ lossis HI siab tshaj 1.0, nws qhia tau hais tias qhov tsis zoo ntawm kev noj qab haus huv tsis yog mob qog noj ntshav muaj peev xwm rau cov neeg siv cov khoom siv pov tseg ENDS. Cov qog nqaij hlav cuam tshuam nrog cov khoom siv pov tseg ENDS siv raws li hauv qab no:𝐶𝑎𝑛𝑐𝑒𝑟 𝑅𝑖𝑠𝑘𝑗=𝐿𝐴𝐷𝐷′𝑗×𝐶𝑆𝐹𝑗 {<10−6 Acceptable cancer risk >10−6 Kev pheej hmoo mob qog noj ntshav tsis txaus siab������ �����=����'�×���� {<10−6 Acceptable cancer risk >10-6 Kev pheej hmoo mob qog noj ntshav tsis txaus
(8)
qhov twg 𝐶𝑆𝐹𝑗���� yog qhov luam tawm kab mob qog noj ntshav (piv txwv li, mob qog noj ntshav) ntawm ib qho tshwj xeeb ENDS tshuaj j (organic chemical lossis hlau). Rau kev ntsuas kev pheej hmoo mob qog noj ntshav, kwv yees qhov kev pheej hmoo mob qog noj ntshav uas siab tshaj 10−6(ib ntawm ib lab) qhia tias muaj kev pheej hmoo mob qog noj ntshav rau cov neeg siv cov khoom siv pov tseg ENDS. Cov txiaj ntsig ntawm RfD, RfC, thiab CSF hauv Equations (7) thiab (8) rau kev ntsuam xyuas mob qog noj ntshav thiab tsis mob qog noj ntshav tau suav sau los ntawm US EPA thiab CalEPA cov vev xaib official [31,32,33,34].3. Cov txiaj ntsig
3.1. Pom cov khoom hauv ENDS Aerosol
Table 1 thiab Table 2 qhia cov (xaiv) cov tshuaj organic thiab hlau kuaj pom los ntawm aerosol tsim los ntawm ob cov khoom siv ENDS pov tseg, Puff Bar (Grape) thiab Air Bar (Ice Watermelon Ice), feem. Cov txiaj ntsig tau raug qhia raws li qhov loj ntawm cov khoom kuaj pom ntawm lub lim (ng), uas yog qhov nruab nrab ntawm cov qauv lim triplicate ntawm tib theem MOUDI. Rau cov organic tebchaw, raws li peb cov tshuaj ntsuam xyuas, ob qho tib si Puff Bar (Grape) thiab Cua Bar (Ice Watermelon Ice) muaj nicotine, propylene glycol (PG), glycerol (VG), benzoic acid, triethyl citrate, ethyl maltol, thiab {{2. }}hexen-1-ol. Nws paub tias PG thiab VG yog cov khoom hnyav uas feem ntau siv hauv e-kua ntawm ENDS cov khoom. Tsis tas li ntawd, Puff Bar kuj muaj methyl anthranilate, -terpineol, thiab perillartine, whereas Air Bar kuj muaj benzyl cawv, vanillin, melonal, methyl dihydrojasmonate, thiab -decalactone. Organic chemicals xws li vanillin, melonal, ethyl maltol, thiab benzyl cawv yog ntxiv ua cov tshuaj tsw qab [35]. Rau kev tsom xam hlau, peb tsuas yog teev cov hlau uas tau sau tseg tias muaj feem cuam tshuam rau kev noj qab haus huv hauv Table 1 thiab Table 2. Cov hlau uas kuaj pom ntawm cov ntxaij lim dej muaj xws li chromium, nickel, manganese, txhuas, txhuas, thiab zinc, tag nrho cov ntaub ntawv tau sau tseg. ua rau tsis zoo rau kev ua pa (thiab txawm tias mob ntsws cancer) thiab hauv nruab nrab paj hlwb [18]. Table 1 thiab Table 2 kuj nthuav qhia qhov loj ntawm ENDS aerosol sau los ntawm MOUDI raws li qhov sib sau ua ke aerosol loj. Zuag qhia tag nrho, qhov loj ntawm cov tshuaj organic feem ntau yog faib thiab peaked nyob ib ncig ntawm theem 6 (collectible aerosol size of 1.8 Greater than or equal to d Greater than or equal to 1.0 µm), uas yog proportional to the mass distribution ( sib npaug particle loj faib) ntawm ENDS aerosol. Txawm li cas los xij, peb tsis tau soj ntsuam cov hlau tom qab xws li kev faib khoom. Nrog rau cov ntaub ntawv loj-nyob ntawm cov khoom siv saum toj no, cov koob tshuaj ntawm cov tshuaj ENDS tshwj xeeb (cov tshuaj lom neeg lossis hlau) tso rau hauv lub ntsws vaper nrog rau cov kev pheej hmoo ntawm kev noj qab haus huv tuaj yeem kwv yees.
Table 1.Cov khoom kuaj pom nyob rau hauv qhov loj-secregated ENDS aerosol cov qauv tsim los ntawm Cua Bar (Ice Watermelon).
Rooj 2.Cov khoom kuaj pom nyob rau hauv qhov loj-seegated ENDS cov qauv aerosol tsim los ntawm Puff Bar (Grape).
3.2. Kwv yees li kev ua pa tso pa ntawm cov tshuaj ENDS
Table 3 thiab Table 4 qhia qhov kwv yees ADD thiab LADD rau cov organic chemicals thiab hlau teev nyob rau hauv Table 1 thiab Table 2. Qhov kwv yees ADD thiab LADD raug xam raws li qhov sib npaug (1)–(6), suav txog qhov tseeb ENDS kev siv tsis tau. , aerosol loj-nyob ntawm cov khoom muaj pes tsawg leeg, thiab cov pa aerosol respiratory deposition feem. Qhov ADD thiab LADD ntsuas qhov ua pa tso tawm ntawm ENDS cov khoom txaus siab. Raws li tau pom nyob rau hauv Table 3 thiab Table 4, cov koob tshuaj tso rau nicotine, propylene glycol, glycerol, thiab benzoic acid tau siab dua li lwm cov tshuaj organic. Ntawm cov hlau, zinc, txhuas, npib tsib xee, thiab chromium tended kom muaj cov tshuaj ntau dua. Feem ntau, Air Bar (Ice Watermelon Ice) ua rau muaj kev tso nyiaj ntau dua ntawm cov tshuaj organic thiab hlau piv rau Puff Bar (Grape). Tshwj xeeb tshaj yog, ENDS aerosol tsim los ntawm Cua Bar (Ice Watermelon Ice) muaj kwv yees ntau dua ntawm cov tshuaj nicotine, propylene glycol, glycerol, chromium, npib tsib xee, manganese, txhuas, txhuas, thiab zinc, piv rau qhov ntawm Puff Bar (Grape).
Table 3.Kwv yees cov koob tshuaj rau lub ntsws thiab mob qog noj ntshav thiab tsis yog mob qog noj ntshav ntawm ENDS aerosol tsim los ntawm Air Bar-Watermelon Ice.
Rooj 4.Kwv yees cov koob tshuaj rau lub ntsws thiab mob qog noj ntshav thiab tsis mob qog noj ntshav ntawm ENDS aerosol tsim los ntawm Puff Bar-Grape.
3.3. Kwv yees mob qog noj ntshav thiab tsis mob qog noj ntshav ntawm ENDS tshuaj
Cov kev pheej hmoo mob qog noj ntshav thiab tsis mob qog noj ntshav rau cov hlau uas tau xaiv hauv ENDS aerosol tau kwv yees raws li ADD thiab LADD sib raug thiab cov txiaj ntsig tau nthuav tawm hauv Table 3 thiab Table 4. Cov lus no kuj qhia txog qhov tseem ceeb ntawm CSF uas tau luam tawm los ntawm Asmeskas EPA thiab CalEPA thiab tau siv rau hauv peb qhov kev kwv yees kev pheej hmoo mob qog noj ntshav [32]. Ntawm cov hlau uas muaj nyob rau hauv aerosol tsim los ntawm Cua Bar (Ice Watermelon Ice), kwv yees kev pheej hmoo mob qog noj ntshav ntawm chromium thiab npib tsib xee yog 1.0 × 10−3thiab 1.5 × 10−6, ntsig txog, uas yog suav tias yog ntau tshaj qhov txaus ntshai ntawm 10−6. Rau cov hlau hauv cov aerosol tsim los ntawm Puff Bar (Grape), kwv yees qhov kev pheej hmoo ntawm kev mob qog noj ntshav ua rau chromium yog 3.9 × 10.−4, uas kuj tshaj li cov pa txaus txaus txaus ntshai. Rau qhov kev kwv yees uas tsis yog mob qog noj ntshav ( ntsuas los ntawm HQ), RfD (lossis RfC) sib raug rau cov hlau uas tau luam tawm los ntawm US EPA thiab CalEPA tau siv (teev hauv Table 3 thiab Table 4) [31,33,34]. Cov txiaj ntsig ntawm qhov kev ntsuam xyuas tsis yog mob qog noj ntshav qhia tau tias qhov txiaj ntsig ntawm HQ rau tag nrho cov hlau hauv Table 3 thiab Table 4 yog tag nrho tsawg dua 1.{{10}}, qhia tias tsis muaj cov hlau ib leeg yuav ua rau muaj kev cuam tshuam loj heev rau kev ua pa lossis CNS. Txawm li cas los xij, thaum suav cov kev pheej hmoo ntawm kev noj qab haus huv uas tsis yog mob qog noj ntshav uas cuam tshuam rau tib lub hom phiaj, nws tau pom tias chromium thiab npib tsib xee hauv aerosol tsim los ntawm Air Bar (Ice Watermelon Ice) ua rau muaj kev pheej hmoo ua pa ntawm HI=1.14, uas yog siab tshaj qhov tau txais qib ntawm 1.0, qhia txog qhov muaj feem cuam tshuam rau kev ua pa tsis zoo (tsis yog mob qog noj ntshav) ntawm cov neeg uas niaj hnub siv Air Bar (Ice Watermelon Ice). Txawm li cas los xij, cov teebmeem zoo sib xws tsis pom muaj nyob hauv aerosol tsim los ntawm Puff Bar (Grape).
4. Kev sib tham
Cov txiaj ntsig tau los ntawm qhov kev sim no tau ua rau muaj qhov tsis txaus ntawm cov ntaub ntawv los ntawm kev muab kev kwv yees kom raug ntau dua ntawm cov kab mob ua pa tso tawm thiab mob qog noj ntshav thiab tsis muaj mob qog noj ntshav cuam tshuam txog kev siv ENDS pov tseg. Los ntawm kev tau txais cov ntaub ntawv loj-segregated chemical constituent cov ntaub ntawv los ntawm ENDS aerosol thiab txiav txim siab aerosol qhov loj me-nyob ntawm cov pa tso pa tawm feem, qhov kev pheej hmoo ntawm kev noj qab haus huv ntawm cov khoom siv ENDS pov tseg tuaj yeem raug soj ntsuam kom raug. Lub zog loj ntawm txoj hauv kev no yog tias nws yuav siv sij hawm rau hauv tus lej ntawm ENDS cov khoom uas tau tso rau hauv tib neeg txoj hlab ntsws.
Peb cov kev tshawb fawb tshuaj ntsuam xyuas tau tshawb pom tias e-luam yeeb aerosol muaj cov tshuaj lom neeg tsis zoo thiab cov hlau (xws li, benzyl cawv, -decalactone, chromium, nickel) uas tau sau tseg ua rau muaj teeb meem ua pa thiab mob ntsws cancer. Peb kuj pom manganese thiab ua rau tshwm sim hauv ENDS aerosol, uas tau paub qhov tsis zoo rau tib neeg CNS. Ntawm cov hlau uas tau kuaj pom, peb pom tias qhov kwv yees qhov kev pheej hmoo mob qog noj ntshav ua pa cuam tshuam nrog chromium los ntawm ob qho tib si pov tseg ENDS cov khoom muaj ntau tshaj qhov txaus ntshai. Qhov kev pheej hmoo mob qog noj ntshav ua pa cuam tshuam rau cov npib tsib xee hauv aerosol los ntawm Cua Bar (Ice Watermelon Ice) kuj tseem ceeb tshaj qhov txaus ntshai. Tsis tas li ntawd, tsis muaj chromium los yog npib tsib xee ib leeg hauv ob qhov khoom siv ENDs pov tseg tau cuam tshuam nrog qhov tsis txaus ntseeg uas tsis yog mob qog noj ntshav. Txawm li cas los xij, thaum xaus rau lawv tus kheej tsis yog mob qog noj ntshav nrog tib lub cev lub cev, peb pom chromium thiab npib tsib xee hauv ENDS aerosol tsim los ntawm Cua Bar (Cov Dej Dej Kua Dej) kom muaj kev cuam tshuam rau kev ua pa. Cov txiaj ntsig no tau hais txog cov pov thawj loj hlob los txhawb qhov kev xav tias cov tshuaj carcinogenic thiab cov tshuaj tsis zoo yog qhov kev txhawj xeeb tiag tiag rau cov neeg siv ENDS tsis tu ncua [18,25,35]. Qhov tseem ceeb, peb kwv yees mob qog noj ntshav thiab tsis mob qog noj ntshav feem ntau qis dua li ntawm Fowles li al. txoj kev tshawb fawb [18], tej zaum vim muaj ntau hom ENDS thiab cov txheej txheem kom tau txais cov hlau ntau. Peb qhov kev kwv yees zoo li yuav muaj tseeb dua tab sis vim tias lawv tau ua raws li kev kwv yees ntawm cov tshuaj tso rau hauv tib neeg txoj kev ua pa nrog rau cov tshuaj ENDS tau sim tshuaj ntsuam xyuas thiab pom hauv ENDS aerosol.
Ib qho kev koom tes tshwj xeeb ntawm txoj kev tshawb fawb no yog tias kev kwv yees ntawm cov koob tshuaj tso tseg thiab cov kev pheej hmoo ntawm kev noj qab haus huv raug cuam tshuam los ntawm qhov loj me ntawm aerosol. Txoj kev siv hauv txoj kev tshawb no tuaj yeem siv ntxiv rau kev tshawb xyuas aerosol toxicity rau lwm yam khoom ENDS. Tshwj xeeb, cov ntaub ntawv loj-raws li cov ntaub ntawv tau txais los ntawm peb cov tshuaj ntsuam xyuas tau muab cov ntaub ntawv tseem ceeb los ntsuas qhov tseeb ntawm cov tshuaj ENDS tshwj xeeb hauv thaj av tib neeg txoj hlab ntsws. Raws li cov ntaub ntawv tau los ntawm MOUDI qhov loj-segregate qauv sau, peb pom tias qhov loj me me faib ntawm yuav luag txhua cov tshuaj organic yog proportional rau ENDS aerosol loj faib. Cov tshuaj organic uas muaj nyob rau hauv ENDS aerosol feem ntau tau faib thiab feem ntau peaked nyob ib ncig ntawm MOUDI Theem 6 (collectible aerosol size: from 1.0 to 1.8 µm). Muab cov ntaub ntawv hais txog qhov loj-dependent aerosol respiratory deposition (qhia hauv Daim Ntawv Ntxiv Ntxiv A Table A1), qhov no txhais tau hais tias 16% ntawm qhov ntau tshaj ENDS aerosol inhaled (1.0–1.8 µm) yuav tso rau hauv vaper lub ntsws nyob rau hauv tracheobronchial airways thiab cheeb tsam alveolar.
Ntxiv nrog rau txoj kev sim ua kom zoo dua qub, txoj kev tshawb no tseem muaj txoj cai tseem ceeb. Txoj kev tshawb no pom tias muaj teeb meem thiab muaj feem cuam tshuam cov organic tebchaw thiab hlau tau kuaj pom nyob rau hauv aerosol los ntawm ob lub ENDS pov tseg, nrog ob peb cov hlau uas ua rau muaj mob qog noj ntshav thiab/lossis tsis yog mob qog noj ntshav. Cov txiaj ntsig no tau hais txog qhov tseem ceeb ntawm kev tswj hwm cov tshuaj phem thiab muaj peev xwm tsim kev puas tsuaj. Ntxiv rau kev txheeb xyuas qhov kev tshawb pom ntawm cov kev tshawb fawb yav dhau los uas cov khoom siv cua sov thiab cov tshuaj tsw qab hauv e-kua ntawm ENDS cov khoom yog qhov chaw ntawm qee yam tshuaj phem [18,25], peb txoj kev tshawb fawb ntxiv tau tsim ib txoj hauv kev kom raug kwv yees ntau npaum li cas ntawm ENDS cov tshuaj muaj feem xyuam. uas tuaj yeem qhia tau zoo dua rau kev tswj hwm cov khoom lag luam luam yeeb los ntawm kev muab kev kwv yees kom raug ntau dua ntawm cov tshuaj lom. Tsis tas li ntawd, raws li FDA tau txwv tsis pub cov khoom qab zib ENDS tshwj tsis yog cov khoom siv pov tseg ENDS vim FDA lub ntsiab lus nqaim ntawm e-luam yeeb cartridge [11], kev tshawb pom los ntawm peb txoj kev tshawb fawb uas tsom tshwj xeeb rau cov khoom siv pov tseg ENDS tau muab ib qho kev tshawb fawb ntxiv rau FDA los txiav txim siab. txuas ntxiv qhov tsw txwv rau cov khoom siv ENDS pov tseg. Tsis tas li ntawd, vim ENDS tuam txhab uas muag feem ntau tshaj tawm tias ENDS muaj nicotine, flavoring chemicals, thiab carrier solutions (piv txwv li, propylene glycol) tab sis downplay lub hav zoov ntawm cov teeb meem tshuaj nyob rau hauv ENDS aerosol [36], stricter cov khoom labeling yuav tsum tau thiab zoo counter kev sib tham campaigns yog tsim nyog. .
Txoj kev tshawb no muaj cov kev txwv uas yuav tsum tau lees paub. Ua ntej, txawm hais tias peb tau tshawb xyuas cov aerosol los ntawm ob qho uas feem ntau tau siv pov tseg ENDS, lawv tsis sawv cev rau tag nrho cov khoom ENDS uas txawv ntawm cov khoom qab zib, qauv, thiab hom. Cov yam ntxwv ntawm cov khoom sib txawv tuaj yeem cuam tshuam nrog kev pheej hmoo ntawm kev noj qab haus huv sib txawv. Piv txwv li, ib txoj kev tshawb nrhiav benzaldehyde hauv ENDS-tsim aerosols pom tias cov qib siab tshaj plaws ntawm benzaldehyde tau kuaj pom hauv cov khoom cherry-flavored ENDS [37]. Cov kev tshawb fawb yav tom ntej yog xav tau los soj ntsuam cov tshuaj aerosol toxicity ua ke nrog cov yam ntxwv ntawm cov khoom lag luam (xws li, tsw, qauv, lub zog hluav taws xob) kom qhia txog kev tswj hwm kev haus luam yeeb ntxiv. Qhov thib ob, peb qhov kev ntsuam xyuas ntawm kev mob qog noj ntshav thiab tsis mob qog noj ntshav muaj feem cuam tshuam nrog cov organic tebchaw thiab cov hlau los ntawm ENDS aerosol yog raws li cov ntaub ntawv pov thawj mob qog noj ntshav (CSP) thiab RfD (lossis RfC) cov ntaub ntawv muab los ntawm EPA thiab CalEPA. Txawm li cas los xij, cov ntaub ntawv zoo li no tsis tau tsim los rau feem ntau ntawm cov tshuaj organic uas tau pom hauv txoj kev tshawb no. Yog li, txawm hais tias cov koob tshuaj txhua hnub xws li ADD thiab LADD tuaj yeem kwv yees rau txhua yam tshuaj lom neeg muaj nyob hauv ENDS aerosol, kev ntsuas kev noj qab haus huv cuam tshuam tsuas tuaj yeem ua tiav rau qee yam tshuaj. Cov kev tshawb fawb yav tom ntej yuav tsum tau tshawb xyuas ntxiv txog kev pheej hmoo kev noj qab haus huv cuam tshuam nrog lwm yam tshuaj thaum lawv cov ntaub ntawv toxicity (piv txwv li, CSP, RfD, thiab RfC) dhau los. Thaum kawg, siv lub koob txhaj tshuaj los kos aerosol los ntawm ENDS cov khoom los tsim ENDS aerosol yuav tsis sawv cev rau qhov xwm txheej tiag tiag ntawm vaping. Txawm li cas los xij, txoj kev no yog ib txoj hauv kev yooj yim thiab muaj txiaj ntsig los ua kom muaj txiaj ntsig zoo ntawm aerosol los ntawm ENDS cov khoom. Rau cov kev tshawb fawb yav tom ntej, kev lag luam e-luam yeeb puffing tshuab xws li CSM-eSTEP (CH Technology USA, Inc., Northeastern, New Jersey) tuaj yeem nrhiav tau los tsim ib tus neeg sawv cev ntau dua thiab txhim khu kev qha ENDS aerosol rau cov kev sim cuam tshuam.
5. Cov lus xaus
Txoj kev tshawb no muab cov txiaj ntsig kev sim muaj txiaj ntsig ntawm kev ua pa tso tawm cov tshuaj siv nrog ENDS cov khoom siv pov tseg nrog kev txiav txim siab ntawm aerosol size-dependent ENDS cov khoom siv thiab cov tshuaj aerosol respiratory deposition fractions, uas ua rau muaj tseeb dua mob qog noj ntshav thiab tsis yog mob qog noj ntshav. Cov txheej txheem thiab kev tshawb pom los ntawm txoj kev tshawb fawb tuaj yeem pab txhawb rau cov ntaub ntawv tseem ceeb ntawm ENDS aerosol toxicity thiab tuaj yeem qhia rau yav tom ntej cov kev tshawb fawb loj uas tshawb xyuas kev noj qab haus huv cuam tshuam nrog ENDS. Cov kev tshawb pom kuj tseem tuaj yeem qhia txog kev tswj hwm kev haus luam yeeb xws li txuas ntxiv tsoomfwv qhov kev txwv txiav rau cov khoom siv ENDS pov tseg, siv cov khoom siv nruj dua cov ntawv sau npe, thiab tsim cov kev sib txuas lus zoo los tawm tsam kev noj qab haus huv rau pej xeem ntawm cov khoom tshiab ENDS.
Sau Kev Pab Txhawb
W.-CS, H.-CL thiab AB tau tsim thiab tsim txoj kev tshawb fawb. H.-CL thiab AB tau tshawb nrhiav cov ntaub ntawv thiab muab cov ntsiab lus ntawm cov kev tshawb fawb yav dhau los. W.-CS tau ua haujlwm hauv chav kuaj. H.-CL tau soj ntsuam kev pheej hmoo ntawm kev noj qab haus huv. H.-CL thiab W.-CS txhais cov kev tshawb pom. H.-CL thiab W.-CS tau sau cov ntawv sau. AB critically revised the manuscript. Txhua tus kws sau ntawv tau nyeem thiab pom zoo rau cov ntawv luam tawm ntawm cov ntawv sau.
Nyiaj txiag
Txoj kev tshawb no tau txais kev txhawb nqa los ntawm R21ES031795 los ntawm National Institute of Environmental Health Sciences (NIEHS) mus rau W.-CS, R01DA049154 los ntawm National Institute on Drug Abuse (NIDA) rau AB thiab H.-CL, thiab kev txhawb nqa los ntawm Southwest Center for Occupational thiab Environmental Health (SWCOEH), Lub Chaw Tiv Thaiv Kab Mob thiab Tiv Thaiv (CDC) National Institute for Occupational Safety and Health (NIOSH) Education and Research Center (T42OH008421) ntawm University of Texas Health Science Center ntawm Houston (UTHealth) Tsev Kawm Ntawv ntawm Public Kev noj qab haus huv.
