Gas Chromatography-Tandem Mass Spectrometry Method for Selective Detection of 2-Nitropropane in Mainstream Cigarette Smoke.

Although 2-nitropropane is a potentially harmful compound present in cigarette smoke, there are few fully-validated, modern methods to quantitate it in mainstream cigarette smoke. We developed an isotope dilution gas chromatography-tandem mass spectrometry (ID-GC-MS/MS) method for the detection of 2-nitropropane in mainstream cigarette smoke. The vapor fraction of mainstream cigarette smoke was collected in inert polyvinyl fluoride gas sampling bags and extracted with hexanes containing isotopically labeled internal standard, then purified and concentrated via solid-phase extraction using a normal phase silica adsorbent and a 100% dichloromethane eluant. This method is sensitive enough to measure vapor phase 2-nitropropane concentrations in the nanogram range, with a 19 ng per cigarette method limit of detection. Product variability estimated from the analysis of 15 cigarette products yielded relative standard deviations ranging from 5.4% to 15.7%, and estimates of precision from two quality control products yielded relative standard deviations of 9.49% and 14.9%. Under the Health Canada Intense smoking regimen, 2-nitropropane in machine-generated mainstream smoke from 15 cigarette products ranged from 98.3 to 363 ng per cigarette.

Bien que le 2-nitropropane soit un composé potentiellement nocif présent dans la fumée de cigarette, il y a peu de méthodes modernes qui sont completement validees pour determiner sa quantité principale dans la fumée de cigarette. Nous avons développé une méthode de spectrométrie de masse en tandem avec chromatographie en phase gazeuse à dilution isotopique (ID-GC-MS / MS) pour la détection du 2-nitropropane dans la fumée principale de cigarette. La fraction vapeur de la fumée principale du cigarette a été collectee dans des sacs d'échantillonnage inertes de fluorure de polyvinyle et extrait à l'hexane contenant un étalon intern marqué isotopiquement, puis purifiée et concentrée par extraction en phase solide en utilisant un adsorbant de silice en phase normale et un éluant à 100% de dichlorométhane. Cette méthode est suffisamment sensible pour mesurer les concentrations de 2-nitropropane en phase vapeur dans la gamme des nanogrammes, avec une limite de détection de 19 ng par cigarette. À partir de l'analyse de 15 produits de cigarette, la variabilité estimée des produits a donné des écarts-types relatifs compris entre 5,4% et 15,7% et les estimations de la précision de deux produits de contrôle de la qualité ont abouti à des écarts-types relatifs de 9,49% et 14,9%. Sous le régime de tabagisme intense de Santé Canada, la concentration de 2-nitropropane présente dans la fumée principale générée par machine à partir de 15 produits de cigarette variait de 98,3 à 363 ng par cigarette.

Determination of Humectants in Tobacco Filler by High Performance Chromatography/Single Quadrupole Mass Spectrometry.

Glycerol, and 1,2-propylene glycol are the humectants most commonly used by the tobacco industry. They are found in a variety of tobacco products and are often present at high levels (~2-5 % w/w). While humectants are generally considered safe, they may serve as precursors in the formation of harmful carbonyl compounds. A selective, precise, and sensitive method for the quantification of several humectants in cigarette filler was developed. The method's sample clean-up is a two-step process consisting of a mechanical extraction, followed by solid phase extraction. Individual humectants are separated, identified, and measured using liquid chromatography coupled to a single quadrupole mass spectrometer as the detector (LC/MS). Detection limits were 0.105, 0.575, and 0.039 mg/cigarette for glycerol, 1,2-propylene glycol and triethylene glycol, respectively. The quantification range for these analytes was 0.4-75.0 mg/cigarette. Twenty-seven brands of domestic commercial cigarettes were evaluated to assess typical levels of humectants in the tobacco filler.

La glycèrine et le 1,2-propylène glycol sont les humectants les plus communément utilisés par l'industrie du tabac. Ils entrent dans la composition de divers produits de tabac oùils sont souvent présents dans des quantités élevées (~2­5% p/p). Alors que les humectants sont, en règle générale, considérés comme sûrs, ils peuvent servir de précurseurs dans la formation de composés carbonylés nocifs. Une méthode sélective, précise et sensible fut mise au point afin de quantifier divers humectants parmi les composants de remplissage des cigarettes. Cette méthode repose sur une épuration de l'échantillon en deux étapes, à savoir une extraction mécanique suivie d'une extraction en phase solide. Les humectants individuels sont séparés, identifiés et mesurés par le biais, en guise de détecteur, d'une chromatographie en phase liquide couplée à une unique spectrométrie de masse quadripolaire (LC/MS). Les seuils de détection s'élevèrent respectivement à 0,105, 0,575 et 0,039 mg/cigarette pour la glycérine, le 1,2 propylèneglycol et le triéthylèneglycol. La plage de quantification de ces analytes fut de 0,4­75,0 mg/cigarette. Vingt-sept marques de cigarettes commercialisées dans le pays furent testées afin d'évaluer les quantités types d'humectants dans le tabac de remplissage.

An isotope dilution ultra high performance liquid chromatography-tandem mass spectrometry method for the simultaneous determination of sugars and humectants in tobacco products.

CDC's Division of Laboratory Sciences developed and validated a new method for the simultaneous detection and measurement of 11 sugars, alditols and humectants in tobacco products. The method uses isotope dilution ultra high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS) and has demonstrated high sensitivity, selectivity, throughput and accuracy, with recoveries ranging from 90% to 113%, limits of detection ranging from 0.0002 to 0.0045µg/mL and coefficients of variation (CV%) ranging from 1.4 to 14%. Calibration curves for all analytes were linear with linearity R2 values greater than 0.995. Quantification of tobacco components is necessary to characterize tobacco product components and their potential effects on consumer appeal, smoke chemistry and toxicology, and to potentially help distinguish tobacco product categories. The researchers analyzed a variety of tobacco products (e.g., cigarettes, little cigars, cigarillos) using the new method and documented differences in the abundance of selected analytes among product categories. Specifically, differences were detected in levels of selected sugars found in little cigars and cigarettes, which could help address appeal potential and have utility when product category is unknown, unclear, or miscategorized.

The use of charcoal in modified cigarette filters for mainstream smoke carbonyl reduction.

Carbonyls are harmful and potentially harmful constituents (HPHCs) in mainstream cigarette smoke (MSS). Carbonyls, including formaldehyde and acrolein, are carcinogenic or mutagenic in a dose-dependent manner. Past studies demonstrate significant reduction of HPHCs by charcoal filtration. However, limits of charcoal filtration and cigarette design have not yet been investigated in a systematic manner. Objective data is needed concerning the feasibility of HPHC reduction in combustible filtered cigarettes. This systematic study evaluates the effect of charcoal filtration on carbonyl reduction in MSS. We modified filters of ten popular cigarette products with predetermined quantities (100-400 mg) of charcoal in a plug-space-plug configuration. MSS carbonyls, as well as total particulate matter, tar, nicotine, carbon monoxide (TNCO), and draw resistance were quantified. Significant carbonyl reductions were observed across all cigarette products as charcoal loading increased. At the highest charcoal loadings, carbonyls were reduced by nearly 99%. Tar and nicotine decreased modestly (<20%) compared to reductions in carbonyls. Increased draw resistance was significant at only the highest charcoal loadings. This work addresses information gaps in the science base that can inform the evaluation of charcoal filtration as an available technological adaptation to cigarette design which reduces levels of carbonyls in MSS.