Separation and quantitation of monovalent anionic and cationic species in mainstream cigarette smoke aerosols by high-performance ion chromatography

Evaluation of two derivatization reagents for the determination by LC-MS/MS of ammonia in cigarette mainstream smoke

Ammonia in cigarette mainstream smoke was quantified by LC-MS/MS after derivatization. Two different reagents, fluorescamine and dansyl chloride, were investigated, but only the latter gave stable derivatives; therefore, it was considered the most appropriate choice. Smoke samples were collected on a Cambridge filter pad followed by an impinger containing a solution of hydrochloric acid. Ammonia was then derivatized with a 18.5 mM solution of dansyl chloride in acetonitrile at 70 °C for 30 min in a vial with the internal standard, (15)ND(4)Cl. The resulting derivative was analyzed by LC-MS/MS detection with an atmospheric pressure chemical ionization (APCI) interface in the positive ionization mode using multiple-reaction monitoring (MRM). Good linearity was obtained in the concentration range of 0.02-1.65 μg/mL (r(2) ≥ 0.999), and the limit of detection (LOD) was established at 0.006 μg/mL. This method has the advantage of being sensitive, efficient, and reliable and is not hindered by interferences from the sample matrix. It should thus be considered a reference method of choice for the determination of ammonia in smoke.

Gas/particle partitioning of two acid-base active compounds in mainstream tobacco smoke: nicotine and ammonia

Gas/particle (G/P) partitioning constant (Kp) values are reported for nicotine and ammonia for mainstream tobacco smoke (MTS) for a selection of cigarettes, "little cigars", and biddies. As K(p)(nic) decreases as a result of the increasing basicity in the MTS, there is an increase in volatility of nicotine from the smoke particulate matter. The "little cigars" and biddies exhibited generally lower K(p)(nic) values and higher unbound ammonia levels than most of the cigarettes, suggesting a correlation between the two parameters. However, within just the cigarettes, there was little correlation. The water content of MTS particulate matter was found to affect both K(p)(nic) and K(p)(amm). Unbound ammonia is actual NH3/NH4+; bound ammonia is comprised of compounds such as amides of ammonia; total ammonia is unbound + bound. Most historical studies of ammonia in MTS have not accurately measured either unbound or total ammonia: the acidic solutions historically employed to determine ammonia in MTS will release ammonia from bound forms by hydrolysis, and the release in those studies may not have been complete. This study concludes that a thorough examination of unbound and bound ammonia in MTS will be required before the role of ammonia in affecting volatility of nicotine in MTS can be understood.

Effects of tobacco smoke condensate on estrogen receptor-alpha gene expression and activity

Metallo-estrogens are a new class of potent environmental estrogens. This study investigates whether tobacco smoke condensate (TSC), which contains metals and metalloids, elicits estrogen-like effects at environmentally relevant doses. Treatment of human breast cancer cells, MCF-7, with 40 microg/ml TSC resulted in a 2.5-fold stimulation of cell growth. TSC decreased the concentration of estrogen receptor (ER)-alpha protein and mRNA (63 and 62%, respectively), and increased the expression of the estrogen-regulated genes, progesterone receptor and pS2 (5- and 2-fold, respectively). In addition, TSC activated ER-alpha in COS-1 or CHO cells transiently transfected with wild-type ER-alpha and an ERE-CAT or an ERE-luciferase reporter gene (11- and 6-fold, respectively). TSC also activated a chimeric receptor (GAL-ER) containing the hormone binding domain of ER-alpha (3.5-fold). It blocked the binding of estradiol to the receptor without altering the affinity of estradiol (K(d) = 2.2-6.8 x 10(-10) m). Transfection assays with ER-alpha mutants identified C381, C447, H524, N532, E523, and D538 in the hormone binding domain as important for activation by TSC. In ovariectomized rats, low doses of TSC [10 or 20 mg/kg body weight (bw)] increased uterine wet weight (1.7- and 2.1-fold), and induced the expression of progesterone receptor and complement C3 in the uterus (2- and 26-fold) and mammary gland (4.4- and 15-fold). Both the in vitro and in vivo TSC effects were blocked by the antiestrogen ICI 182,780, suggesting the involvement of ER. Collectively, these results provide strong evidence that low doses of TSC, acting through the hormone binding domain, exert estrogen-like effects in cell culture and animals.

The role of ammonia in the transfer of nicotine from tobacco to mainstream smoke

This study has examined the possible effects of ammonia-forming ingredients added to tobacco and of ammonia in mainstream (MS) smoke on the nicotine transfer from tobacco to smoke. The U.S. 1998 Marlboro Lights King Size cigarette was used as a control for four test variants that differed from the control as follows: first, a reduction in ammonia-forming ingredients added to the reconstituted tobaccos; second, no ammonia-forming ingredients added to the reconstituted tobaccos; third, no ingredients at all added to the reconstituted tobaccos; and fourth, no ingredients at all added to the entire tobacco blend. Data were obtained on nicotine in tobacco, tar and nicotine and ammonia in MS smoke, soluble ammonia in the cigarette tobacco, "tobacco pH," and "smoke pH" using the FTC machine-smoking paradigm. Previous research on these cigarettes demonstrated that >99% of the MS smoke nicotine was captured and quantified by the FTC method. Statistically significant increases in soluble ammonia and MS smoke ammonia were observed for those cigarettes with ammonia-forming ingredients added to the reconstituted tobacco. However, ingredients, including ammonia and ammonia-forming compounds added to the tobacco or ammonia in the mainstream smoke in the Marlboro Lights King Size cigarette, did not increase the relative nicotine transfer or the "pH of aqueous extracts of MS smoke." "Tobacco pH" and "smoke pH" had no scientific or practical value for the cigarettes in this study.

Analysis of anions in ambient aerosols by microchip capillary electrophoresis

We describe a microchip capillary electrophoresis method for the analysis of nitrate and sulfate in ambient aerosols. Investigating the chemical composition of ambient aerosol particles is essential for understanding their sources and effects. Significant progress has been made towards developing mass spectrometry-based instrumentation for rapid qualitative analysis of aerosols. Alternative methods for rapid quantification of selected high abundance compounds are needed to augment the capacity for widespread routine analysis. Such methods could provide much higher temporal and spatial resolution than can be achieved currently. Inorganic anions comprise a large percentage of particulate mass, with nitrate and sulfate among the most abundant species. While ion chromatography has proven very useful for analyzing extracts of time-integrated ambient aerosol samples collected on filters and for semi-continuous, on-line particle composition measurements, there is a growing need for development of new compact, inexpensive approaches to routine on-line aerosol ion analysis for deployment in spatially dense, atmospheric measurement networks. Microchip capillary electrophoresis provides the necessary speed and portability to address this need. In this report, on-column contact conductivity detection is used with hydrodynamic injection to create a simple microchip instrument for analysis of nitrate and sulfate. On-column contact conductivity detection was achieved using a Pd decoupler placed upstream from the working electrodes. Microchips containing two Au or Pd working electrodes showed a good linear range (5-500 microM) and low limits-of-detection for sulfate and nitrate, with Au providing the lowest detection limits (1 microM) for both ions. The completed microchip system was used to analyze ambient aerosol filter samples. Nitrate and sulfate concentrations measured by the microchip matched the concentrations measured by ion chromatography.

Smoke composition and predicting relationships for international commercial cigarettes smoked with three machine-smoking conditions

The study objectives were to determine the effects of smoking machine puffing parameters on mainstream smoke composition and to express those effects as predicting relationships. Forty-eight commercial Philip Morris USA and Philip Morris International cigarettes from international markets and the 1R4F reference cigarette were machine-smoked using smoking conditions defined by the International Organization of Standardization (ISO), the Massachusetts Department of Public Health (MDPH), and Health Canada (HC). Cigarette tobacco fillers were analyzed for nitrate, nicotine, tobacco-specific nitrosamines (TSNA), and ammonia. Mainstream yields for tar and 44 individual smoke constituents and "smoke pH" were determined. Cigarette constituent yields typically increased in the order ISO<MDPH<HC. Relative yield increases were generally greater for cigarettes with higher initial filter ventilation and were also generally greater for vapor-phase constituents than for particulate-phase constituents. Predicting relationships were developed between ISO tar and ISO, MDPH, and HC constituent yields and between MDPH tar and HC tar and respective smoking condition yields. MDPH and HC constituent yields could be predicted with similar reliability using ISO tar or the corresponding smoking-condition tar. The reliability of the relationships varied from strong to weak, depending on particular constituents. Weak predicting relationships for nitrogen oxides and TSNA's, for example, were improved with inclusion of tobacco filler composition factors. "Smoke pH" was similar for all cigarettes at any one smoking condition, and overall marginally lower at HC conditions than at ISO or MDPH conditions.

A responsive, sensitive, and reproducible dermal tumor promotion assay for the comparative evaluation of cigarette smoke condensates

The mouse dermal initiation/promotion bioassay has been used for several decades to study cigarette smoke condensates (CSCs). However, these studies have used highly variable methodologies that differ in the manner of CSC collection, duration of treatment, mouse strain, number of mice and endpoints measured. In this report, a protocol that uses female SENCAR mice and standardizes many of the procedures is presented. A reference cigarette (University of Kentucky 1R4F), readily available to researchers, was used. This report presents the combined data from four independent studies. Female, SENCAR mice (40/group) were treated with a single dose (75microg) of dimethylbenz[a]anthracene (DMBA) as an initiator, followed 1 week later by treatment (three times/week) with 10, 20 or 40mg "tar"/application of 1R4F CSC for 29 weeks. There were no treatment-related effects on body weights. Histological diagnosis of all masses at study termination indicated a dose-dependent increase in the number of tumor-bearing mice and total tumor number. These studies support the conclusion that the 1R4F cigarette is suitable for use as a reference standard and the protocol presented is an appropriate and standardized model suitable for the comparative evaluation of CSC.

Mainstream smoke constituent yields and predicting relationships from a worldwide market sample of cigarette brands: ISO smoking conditions

The study objective is evaluation of a benchmark approach for predicting mainstream smoke constituent machine-yields for conventional cigarette brands from worldwide markets. Results for ISO smoke yields support the validity of benchmarking when brands, for which yields are to be predicted, have design characteristics within boundaries established by the exploratory brands. Yields of ISO-method mainstream smoke constituents were generally well described by weighted least squares regression relationships with ISO tar (R2>0.80 and coefficient p values <0.05). The impact of the varied chemical composition of cigarette tobaccos from different regions on smoke constituent yields was recognized. Mainstream smoke nitrogen oxides and tobacco-specific nitrosamine (TSNA) yield prediction relationships improved by including tobacco nitrate or TSNA concentration factors in respective independent parameters. For carbon-filter brands, inclusion of a carbon factor improved the predicting relationships for several vapor-phase constituents. Relationships were validated with a subset of additional validation brands. Greater than 90% of the validation brands' smoke chemistry yields were within the 95% prediction intervals. Average differences between measured and predicted yields were generally within the range of one to two measurement standard deviations. The estimation methods proposed relate to machine-smoking conditions and are not intended to reflect the actual exposure of any given consumer to smoke constituents.