卷烟主流烟气气溶胶中酚类物质的粒径分布研究

为研究酚类物质在卷烟主流烟气气溶胶中的粒径分布,采用单通道吸烟机-电子低压撞击器(ELPI),通过12级聚酯薄膜捕集烟气气溶胶粒相物,采用超高效液相色谱-荧光检测方法测定了14种酚类在不同粒径气溶胶中的分布。实验结果表明,本方法捕集得到气溶胶粒相物质量的相对标准偏差小于10%,具有较好的稳定性;超高效液相色谱-荧光检测方法测定14种酚类的线性相关系数R2均大于0.9959,检出限低于1.2 ng/cig,回收率在80.1%~115.0%之间,方法简单快速,准确可靠。采用本方法研究了卷烟主流烟气气溶胶中14种酚类物质含量和浓度的粒径分布,发现除了4-乙基愈创木酚在捕集的气溶胶中未检出外,其它13种酚类物质在不同粒径气溶胶粒相物中的含量分布随粒径增加呈现先增加后减小的趋势,与粒相物质量分布一致,并主要集中在中等粒径(0.261~0.722μm)的粒相物中,在粒径0.431μm的粒相物中含量最高;不同酚类物质在不同粒径气溶胶中的浓度分布趋势有差异,苯酚和单取代苯酚类的浓度分布有特异性,其浓度随着粒径增加呈现先增加后减小的趋势,在中等粒径的粒相物中(0.261~0.722μm)浓度最高;苯二酚类和单取代苯二酚的浓度在0.144~1.166μm的粒相物中分布无明显差异,二取代苯酚类的浓度随着粒径的变化无明显差异。     

卷烟主流烟气气相水分的捕集及气相色谱法测定

提出了用剑桥滤片捕集烟气粒相物,以异丙醇和乙醇为吸收液、两级碰撞捕集器串联捕集烟气气相物,用气相色谱法测定主流烟气粒相和气相水分含量的方法。试验结果表明:线性范围为0.8～6.0g.L-1,相对标准偏差(n=5)小于2.5%之间,回收率为93.46%～106.15%。采用该法对7种卷烟主流烟气中粒相和气相水分进行测定,烟气总水分含量为6.77～9.43mg.支-1,其中气相水分约占总水分的65%～75%,表明气相水分是研究卷烟品质的重要参数。     

离子色谱法测定卷烟主流烟气中的硫化氢

建立了测定卷烟主流烟气中硫化氢含量的离子色谱法.采用玻璃纤维滤片捕集卷烟烟气粒相物,并用0.5%(体积分数)乙二胺-50 mmol/L氢氧化钠-250 mmol/L乙酸钠溶液萃取粒相物,吸收液吸收气相物中的硫化氢,合并粒相萃取液与气相吸收液,经离子色谱柱分离,以1.5 mol/L氢氧化钠-1 mol/L乙酸钠-2%(体积分数)乙二胺(40∶50∶10,体积比)为流动相,安培检测器检测并施加-100 mv的检测电位.运用方法对12种市售卷烟样品进行了测定,结果表明:方法的线性范围为0.1~5.0μg/mL,检出限为1.03μg/mL,定量限为3.41μg/mL,回收率为102.3%~107.2%,相对标准偏差小于5%.方法处理简单、准确度高,可以用于卷烟烟气中硫化氢含量的测定.     

气相色谱-质谱联用法测定卷烟主流烟气中的呋喃

建立了气相色谱-质谱联用(GC/MS)测定卷烟主流烟气中呋喃的方法。方法以N,N-二甲基甲酰胺为吸收液,用两个串联的吸收瓶捕集主流烟气中的呋喃,HP-PLOT Q毛细管柱分离,选择离子监测,外标法定量。两个串联吸收瓶对主流烟气中呋喃的有效捕集率达99%以上;在0.05~2.5μg/m L的浓度范围内,回归方程线性关系良好(R2=0.9999),检出限(LOD)和定量限(LOQ)分别为0.02μg/支和0.06μg/支;平均加标回收率在93.3%~98.1%之间,RSD小于4%,5 h内样品溶液中呋喃含量的变化率小于6%;用本方法对10种卷烟样品进行测定分析,呋喃的含量在7.57~21.15μg/支之间。     

气相色谱-质谱法测定卷烟烟气中苯并[α]芘

卷烟主流烟气用剑桥滤片捕集总粒相物,然后用环己烷超声浸取总粒相物中苯并[α]芘。所得浸取液先经HP-5MS毛细管预柱(0.25mm×1.0mm,0.25μm)净化以保护分离柱和离子源,再经HP-5MS毛细管柱(0.25 mm×30mm,0.25μm)分离后,质谱测定。苯并[α]芘的质量浓度在4～640ng·L~(-1)范围内与其峰面积呈线性关系。方法的日内相对标准偏差(n=7)为2.1%,日间相对标准偏差(n=5)为2.4%。按本法分析了5个卷烟样品,所得苯并[α]芘的测定结果与国标法测定结果一致。     

离子色谱-电感耦合等离子体质谱联用法测定卷烟中Cr(Ⅲ)和Cr(Ⅵ)的含量

称取卷烟烟丝0.200 0g,用100mmol·L-1 EDTA溶液(pH 7.5)20mL,于50℃水浴中提取3h;取此提取液5mL经过炭黑小柱净化,得到烟丝的样品溶液。为制得烟气中粒相物样品溶液,取20支卷烟经转盘吸烟机用静电捕集法捕集烟气中的粒相物;用上述EDTA溶液将捕集管上的粒相物全部冲洗于20mL容量瓶中,定容后在相同条件下提取并净化。将在标准抽吸条件下所得一整支卷烟的烟灰和烟蒂,按上述相同条件用EDTA溶液提取后,取提取液5mL,经0.45μm滤膜过滤,滤液为烟灰和烟蒂的样品溶液。以上所得3份样品溶液分别收集于离子色谱进样瓶中,用IonPac AG11-HG色谱柱分离,用50mmol·L-1硝酸铵溶液(pH 6.8)作为流动相进行洗脱;按所选条件用电感耦合等离子体质谱法测定洗脱液中Cr(Ⅲ)和Cr(Ⅵ)。结果表明:Cr(Ⅲ)与Cr(Ⅵ)的质量浓度分别在0.15~1 500,0.06~600μg·L~(-1)内与对应的峰面积之间呈线性关系,检出限(3S/N)分别为0.15,0.06μg·L~(-1)。用标准加入法测得方法的回收率依次在95.2%~98.6%,90.6%~96.8%;对同一样品重复进样7次,峰面积的相对标准偏差依次为3.3%,4.8%。结果显示:卷烟中铬的主要来源于烟丝,以Cr(Ⅲ)为主;在抽吸过程中,熔点较低的Cr(Ⅲ)化合物容易转移至烟气的粒相物中,从而被滤嘴截留或进入主流烟气中,而Cr(Ⅵ)则大部分残留在烟灰中。     

超低温溶剂提取-全二维气相色谱/飞行时间质谱法测定卷烟主流烟气中有机酸成分

建立了超低温溶剂提取结合全二维气相色谱/飞行时间质谱(GC×GC-TOF/MS)测定卷烟主流烟气中有机酸类成分的方法。首先利用乙醚为提取溶剂的超低温溶剂提取装置对卷烟主流烟气进行捕集,然后将提取液通过液液萃取、N,O-双(三甲基硅烷)三氟乙酰胺(BSTFA)衍生化后,以DB-1(30 m×0.25 mm,1.0μm)为一维色谱柱、DB-wax(1.5 m×0.1 mm,0.1μm)为二维色谱柱组成的柱系统对目标物进行分离,在调制周期为6 s、质量扫描范围为m/z 45~450的条件下,卷烟主流烟气中12种有机酸成分可以在58 min内得到准确的检测。实验结果表明,卷烟主流烟气中12种有机酸标准曲线相关系数R2>0.99,加标回收率为80.2%~107.8%,相对标准偏差(RSD)的范围为0.4%~12.1%(n=5),方法检出限为1.3~24.5μg/kg,定量限为4.1~77.1μg/kg。     

吸收瓶捕集-超高效液相色谱法测定卷烟侧流烟气中的酚类化合物

建立了室温条件下使用吸收瓶捕集卷烟侧流烟气中的酚类化合物,超高效液相色谱法(UPLC)分离和定量分析的方法。采用鱼尾罩、剑桥滤片收集侧流烟气粒相物,再用装有乙酸(1+99)溶液的吸收瓶捕集穿过剑桥滤片的气相成分,然后用乙酸(1+99)溶液超声萃取总粒相物与气相物,萃取液经过微孔滤膜后直接进行UPLC分析。该方法对侧流烟气中酚类化合物分析,样品回收率为95.2%~105.6%,检测限为4.56~20.47 ng/cig,RSD(n=5)为0.70%~9.2%,分析时间6 min。     

气相色谱法测定卷烟烟气中涕灭威残留量

提出了气相色谱法测定卷烟烟气中涕灭威残留量的分析方法。通过吸烟机抽吸捕集卷烟主流烟气总粒相物和主流烟气气相物后经甲醇萃取,所得萃取液中涕灭威及其代谢物通过过氧化氢氧化转化为涕灭威砜,再用二氯甲烷提取除去干扰,然后采用DB-1701弹性石英毛细管柱分离,脉冲火焰光度检测器检测,外标法定量。方法的检出限(3S/N)为0.01μg·g~(-1),主流烟气总粒相物中涕灭威的回收率在99.0%～101.0%之间,相对标准偏差(n=6)为4.7%～10.2%;主流烟气气相物中涕灭威的回收率在97.7%～99.3%之间,相对标准偏差(n=6)为5.4%～9.6%。     

气相色谱-质谱法测定主流烟气中的植物碱

采用气相色谱-质谱法测定主流烟气中的烟碱、降烟碱、麦斯明、假木贼碱和新烟草碱。捕集有总粒相物的剑桥滤片加入内标后,用50g·L-1氢氧化钠溶液将植物碱游离出来,经乙酸乙酯萃取后,在DB-35MS色谱柱上分离,采用选择离子扫描模式。5种植物碱的浓度与峰面积在一定范围内呈线性关系。烟碱的检出限(3S/N)为12μg·支-1,其他4种植物碱的检出限(3S/N)为0.30~2.5μg·支-1。5种植物碱的加标回收率在86.5%~108%之间,测定值的相对标准偏差(n=6)在1.7%~4.5%之间。     

单颗粒气溶胶飞行时间质谱仪分析香烟烟气气溶胶

单颗粒气溶胶飞行时间质谱可同时对气溶胶单颗粒的粒径大小、化学成分进行实时、在线检测.本研究介绍了新近研制的单颗粒质谱仪的原理、结构、主要技术指标及对香烟烟气气溶胶的应用研究.仪器采用空气动力学透镜聚焦,双光束粒径测量系统确定颗粒物的空气动力学直径,激光电离系统实现颗粒物精确电离,通过双极有网反射飞行时间质量分析器实现正负离子同时检测.香烟检测结果表明,在颗粒物粒径分布上,新鲜香烟烟气颗粒范围较老化烟气宽.在气溶胶化学成分上,老化烟气颗粒物与新鲜烟气相比,尼古丁,氰酸盐,硝酸盐,硫酸盐及铵盐5种成分的数浓度百分比都有所增加,而含C1-的数浓度百分比减少.原因可能是由于烟气由气相到粒相之间的转化,及颗粒物与空气中的气体发生了非均相反应;C1-老化之后的减少是因为HN03与CI-之间的非均相反应.     

Study of the aerosol fragrances of eugenol derivatives in Cananga odorata using diffuse reflectance infrared Fourier transform spectroscopy and gas chromatography

The purpose of this study was to develop and test a diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS) method, a fast and non-destructive method without extraction, and compare it with the standard gas chromatography (GC) method currently used. A micro-orifice uniform deposit impactor (MOUDI) was used to sample all the size distributions of the aerosol particles of essential oils to investigate the relation between size distributions and the indoor concentration distributions of ylang essential oils. Correlation coefficients for DRIFTS and GC were 0.9904, 0.9910, 0.9913, and 0.9983 for eugenol, isoeugenol, methyl ether, and eugenyl acetate, respectively. The results showed that the concentrations of the four eugenol derivatives of smoke were approximately three times higher than those of mist. Additionally, the major size distributions of aerosol were 0.19 μm and 1.8 μm for the smoke and mist methods, respectively. Because these two methods produce similar results, DRIFTS is a practical method for assessing these fragrances in aerosols.     

Fast analysis of nicotine related alkaloids in tobacco and cigarette smoke by megabore capillary gas chromatography

A novel fast megabore capillary gas chromatographic (MCGC) method for analysis of 7 nicotine related alkaloids in tobacco and cigarette smoke, including nicotine, nornicotine, myosmine, nicotyrine, anabasine, anatabine and 2,3-dipyridyl, was developed. The use of megabore capillary column GC methodology, equipped with flame ionization detector (FID), provided rapid, unambiguous nicotine related alkaloids analysis. One gram flue-cured tobacco (or Cambridge filter pad), 20 ml ether, and 5 ml 10% sodium hydroxide solution, added with n-heptadecane as the internal standard, were placed in a flask, and the flask was capped and placed in an ultrasonic bath for 15 min. A 1 microl volume was analyzed by capillary GC operating in split-injection mode on a mega bore Simplicity-5 column. This simple procedure was compared with the previously reported packed column GC method and the Griffith still-colorimetric method. The application of the method for analysis of various flue-cured tobaccos and cigarette smoke was discussed.     

LC-MS-MS法测定卷烟侧流烟气中的亚硝胺

采用鱼尾罩和剑桥滤片捕集卷烟侧流烟气中的粒相颗粒物,建立了LC-MS-MS法测定卷烟侧流烟气中4种烟草特有的亚硝胺TSNAs(NNN,NAT,NAB,NNK)。剑桥滤片在醋酸铵水溶液中机械振荡40min后提取萃取液,萃取液经0.22μm滤膜过滤后,直接进LC-MS-MS分析。鱼尾罩壁上的冷凝物用甲醇溶液清洗,洗液通过氮吹浓缩后,采用PCX固相萃取小柱净化进样分析。测定方法的检测限为0.09～0.25ng/mL,线性相关系数均大于0.996,4种TSNAs的回收率均在88.2%～110.2%之间,相对标准偏差RSD均小于7%。方法适合作为卷烟侧流烟气中四种烟草特有亚硝胺(TSNAs)的定量分析方法。     

Determination of Nicotine-Related Alkaloids in Tobacco and Cigarette Smoke by GC-FID

A simple and accurate method, gas chromatography (GC) with flame-ionization detection (FID) has been used for determination of the four main nicotine-related alkaloids in tobacco. Tobacco samples were treated with a small quantity of aqueous ammonia solution, to loosen the tobacco tissue and to convert all alkaloids to free bases, then extracted with 1:3 CH₃OH-CH₂Cl₂. A method for further simultaneous and comprehensive determination of six nicotine-related alkaloids in cigarette smoke was also developed. Because of the complexity of the cigarette smoke matrix and the small amounts of alkaloids, except nicotine, in cigarette smoke, the smoke extract was concentrated after removal of the acidic and neutral fractions. To reduce the adsorption and thermal degradation of alkaloids in the liner, especially for nornicotine, a suitable injector temperature was selected and pulsed injection mode was studied. Different cigarette smokes and tobaccos were analyzed for levels of nicotine-related alkaloids.Revised: 3 January and 21 March 2005     

Screening of urban aerosol particulate composites for selected metal distribution and their dependence on meteorological parameters

Local atmospheric aerosol particulate samples, collected as composites on daily 6-12 hour basis, at Quaid-i-Azam University campus, Islamabad, Pakistan, using high volume sampling technique, were analysed for Pb, Na, K, Fe, Mn, Cd, Cr, Ni, Zn and Co by FAAS method. The monitoring period ran from October, 2001 through March, 2002, with a total of 105 samples collected on cellulose filters, treated in part with the HNO3-based wet digestion method for metal quantification, and for particle size distribution separately. The metal content of the aerosols was examined in relation to dependence on meteorological parameters, such as temperature, relative humidity, wind speed, sun shine and pan evaporation. Statistical correlation analysis was conducted for multiple metal pairs in aerosols, and the data were examined in relation to meteorological parameters and relevant aerosol particle size fractions. The study revealed no viable strong correlation between the meteorological parameters and metal levels; in general, however, a significant positive correlation was found for temperature. A strong positive correlation was observed for PM<25 and PM2.5-10. For coarse particles (PM10-100 and PM>100), however, a negative correlation was observed. The levels of Na, K, Fe and Zn were found in the range of 1-5 microg/m3 while those for the rest of the metals in the sub microg/m3 range. Principal component analysis and cluster analysis were performed on dataset for source identification and appointment. Largest contribution (33%) was shown by the industrial emissions followed by traffic/road dust (16.7%).     

Gas chromatography-mass spectrometry of carbonyl compounds in cigarette mainstream smoke after derivatization with 2,4-dinitrophenylhydrazine

An improved gas chromatography-mass spectrometry (GC-MS) method was described for the analysis of carbonyl compounds in cigarette mainstream smoke (CMS) after 2,4-dinitrophenylhydrazine (DNPH) derivatization. Besides formaldehyde, acetaldehyde, acetone, acrolein, propionaldehyde, methyl ethyl ketone, butyraldehyde, and crotonaldehyde that are routinely analyzed in cigarette smoke, this technique separates and allows the analysis of several C4, C5 and C6 isomeric carbonyl compounds. Differentiation could be made between the linear and branched carbon chain components. In cigarette smoke, the branched chain carbonyls are found at higher level than the linear chain carbonyls. Also, several trace carbonyl compounds such as methoxyacetaldehyde were found for the first time in cigarette smoke. For the analysis, cigarette smoke was collected using DNPH-treated pads, which is a simpler procedure compared to conventional impinger collection. Thermal decomposition of DNPH-carbonyl compounds was minimized by the optimization of the GC conditions. The linear range of the method was significantly improved by using a standard mixture of DNPH-carbonyl compounds instead of individual compounds for calibration. The minimum detectable quantity for the carbonyls ranged from 1.4 to 5.6 microg/cigarette.     

Investigation of airborne particles by inductively coupled plasma emission spectrometry calibrated with monodisperse aerosols

An emission spectrometric method for the investigation of airborne particles has been developed. Sample air was directly introduced into an ICP to vaporize and atomize the particles and to excite the atoms or ions. The emission signal from the ICP was observed as a flash for each particle when the particle concentration was sufficiently low. The flashes were converted into electric pulses, which were counted by a pulse height analyzer. Thus, for particles of homogeneous composition the particle concentration and size distribution were determined simultaneously for a given element. To calibrate the measuring system, monodisperse aerosols were prepared by using a vibrating orifice monodisperse aerosol generator. Sodium chloride, calcium nitrate and copper nitrate aerosols were generated using solutions of known concentrations. The concentration and size distribution of copper particles were determined in aerosols generated by a small arc at the switch of a lamp socket when a 200-W lamp was turned off. Most of the particles were less than 1μm in diameter with a peak distribution at 0.7 μm. The smallest particles measurable for calcium oxide and copper were 0.1 and 0.3 μm in diameter, respectively.     

Characterization of the Vitrocell® 24/48 <Emphasis Type="Italic">in vitro</Emphasis>aerosol exposure system using mainstream cigarette smoke

Background

Only a few exposure systems are presently available that enable cigarette smoke exposure of living cells at the air-liquid interface, of which one of the most versatile is the Vitrocell® system (Vitrocell® Systems GmbH). To assess its performance and optimize the exposure conditions, we characterized a Vitrocell® 24/48 system connected to a 30-port carousel smoking machine. The Vitrocell® 24/48 system allows for simultaneous exposure of 48 cell culture inserts using dilution airflow rates of 0-3.0 L/min and exposes six inserts per dilution. These flow rates represent cigarette smoke concentrations of 7-100%.

Results

By characterizing the exposure inside the Vitrocell® 24/48, we verified that (I) the cigarette smoke aerosol distribution is uniform across all inserts, (II) the utility of Vitrocell® crystal quartz microbalances for determining the online deposition of particle mass on the inserts, and (III) the amount of particles deposited per surface area and the amounts of trapped carbonyls and nicotine were concentration dependent. At a fixed dilution airflow of 0.5 L/min, the results showed a coefficient of variation of 12.2% between inserts of the Vitrocell® 24/48 module, excluding variations caused by different runs. Although nicotine and carbonyl concentrations were linear over the tested dilution range, particle mass deposition increased nonlinearly. The observed effect on cell viability was well-correlated with increasing concentration of cigarette smoke.

Conclusions

Overall, the obtained results highlight the suitability of the Vitrocell® 24/48 system to assess the effect of cigarette smoke on cells under air-liquid interface exposure conditions, which is closely related to the conditions occurring in human airways.