bluuebunny/crossref_metadata_2025 huggingface dataset:
Effects of Curing and Fertilization on Nitrosamine Formation in Bright and Burley Tobacco
Authors: Chamberlain WJ , Chortyk OT
Published: July 2016

A bright and a Burley tobacco were grown at four fertilization rates and each tobacco was then both flue-cured and air-cured. Levels of alkaloids and nitrosamines were found to increase with increasing fertilization levels. Levels of alkaloids, N-nitrosonornicotine (NNN), and other tobacco-specific nitrosamines (TSNA) were consistently higher in the Burley tobacco than in the bright tobacco, regardless of curing method. In comparing the effects of curing, it was found that NNN and total TSNA levels were higher in the midrib than in the lamina of the air-cured samples, while just the opposite was found for the flue-cured samples. Flue-curing bright tobacco produced three times the level of TSNA vs air-curing the same tobacco. On the other hand, flue-curing Burley tobacco reduced the alkaloids, but greatly increased the TSNA in the lamina. As midribs from the air-cured Burley leaves had three times the TSNA concentration of the lamina, the use of air-cured midribs in tobacco products should be avoided. It was concluded that lower fertilization levels and careful manipulations of curing parameters could lower nitrosamine levels in cured tobacco.
A Preliminary Study on the Fermentation Anomalies of Dark-Fired Tobacco Previously Stored in a Modified Atmosphere at High Absolute Humidity
Authors: Ricciardi M , Aureli G , Dattilo BS
Published: July 2016

In the course of industrial fermentation of dark-fired cigar filler leaf tobacco which was previously stored in a modified atmosphere (air and carbon dioxide), some anomalies, such as a slow temperature increase, mould development, unpleasant odours, little or no ammonia production, were observed. For the investigation of these phenomena a laboratory fermentation system was developed. This model system made it possible to change the values of the main parameters influencing the course of fermentation, to take samples for microbiological and chemical analyses, and to carry out some qualitative evaluations. Fermentations of tobacco stored in modified atmosphere and artificially inoculated with bacteria (Gen. Bacillus) were carried out.
Determination of 25 Low Molecular Weight Carbohydrates in Tobacco by High Performance Ion Chromatography
Authors: Ramusino MC , Dattilo BS , Lucibello A , Rossi SG
Published: July 2016

A High Performance Ion Chromatographic method for the qualitative and quantitative determination of low molecular weight carbohydrates in tobacco leaf is described. The carbohydrates were separated by running isocratic or gradient elutions on columns packed with amino-modified polystyrene divinylbenzene phases, using 0.1 N NaOH as eluent. The compounds were detected by a Pulsed Amperometric Detector, after post-column addition of 1 N NaOH solution. Twenty-two and twenty-four carbohydrates out of twenty-five were separated by isocratic and gradient elution, respectively. Some mono and disaccharides were identified in tobacco samples by their retention times and some quantitative determinations of glucose, fructose, inositol and saccharose were carried out using different varieties of tobacco.
Specific Structural Analysis of Solanesol and Related Compounds by Fast Atom Bombardment in Combination with Tandem Mass Spectrometry
Authors: Jensen NJ , Sumpter T
Published: July 2016

Rapid identification of solanesol even in the presence of a complex matrix can be accomplished using fast atom bombardment (FAB) mass spectrometry in combination with tandem mass spectrometry methods. FAB MS analysis using a nitrobenzyl alcohol matrix doped with lithium yields an abundant (M + Li)+ ion of m/z of 637 which is a very characteristic marker for the presence of solanesol and is quite sufficient for screening for the presence of solanesol in many cases. MS/MS analysis of this ion produces a spectrum which yields specific structural information regarding each isoprene unit of the entire structure. Furthermore, these methods are very useful for characterizing unknowns as demonstrated by the characterization of diol, triol and ester impurities in commercially available solanesol. Application of the MS/MS/MS analysis provides insight into the fragmentation mechanism and can be a useful alternative to conventional labeling methods for confirming spectral interpretations.
Intercept-Reactant Method for the Determination of Aromatic Amines in Mainstream Tobacco Smoke
Authors: Grimmer G , Schneider D , Naujack KW , Dettbarn G , Jacob J
Published: July 2016

A method for the determination of aromatic amines in mainstream smoke of mechanically smoked cigarettes has been developed. The fast reaction of aromatic amines with other smoke constituents formed during the combustion process can be significantly reduced by the addition of an excess of p-toluidine to the acidic collecting solution. From this point the p-toluidine as intercept reactant immediately stabilizes the originally formed amines and results in high recovery rates. The method allows the gas chromatographic determination of aniline, o- and m-toluidine, 1- and 2-aminonaphthalene, 2- and 4-aminobiphenyl, 1-, 2- and 4-aminofluorene, 3-aminofluoranthene, 1-aminopyrene and 6-aminochrysene in the mainstream smoke of a single cigarette. d5-Aniline, d7-2-aminonaphthalene, d9-4-aminobiphenyl as well as fluoranthene and chrysene were used as internal standards. By this new method, 21 ng of 2-aminonaphthalene and about 3,6 ng of 4-aminobiphenyl have been detected in the mainstream smoke of a common blend filter cigarette. As expected, these contents were higher in cigarettes manufactured from alkaline tobacco.
The Removal of Stems from Cut Tobacco
Authors: Zielke D , Liebe R
Published: July 2016

The presence of stems in cut tobacco is detrimental to cigarette quality, resulting in problems during production particularly on today's high-speed makers. Incomplete threshing and the use of unthreshed semi-Oriental tobaccos can increase the stem content in the cut tobacco considerably. The percentage of stems present in cut tobacco was investigated by HauniMaschinenbau AG specifically for semi-Oriental tobacco. Their findings show that not all stems present in the strips or lamina after cutting are classified as “objectionable”. However, the percentage of objectionable stems in the cut tobacco is not inconsiderable and depends on the thickness of the stems present. Reducing the objectionable stem contingent in cut tobacco is therefore a crucial concern of many cigarette manufacturers who set great store on ensuring high-quality product. HauniMaschinenbau AG offers a cut tobacco separator which has been specially designed for this purpose and also used as a cooler. A corresponding model is available in the HauniMaschinenbau AG pilot plant in Hamburg for tests using the customers’ own tobacco.
Conference Report: 53rd Tobacco Science Research Conference (TSRC), September 12-15, 1999, in Montreal, Canada
Authors: Paschke T
Published: July 2016

The 53rd Tobacco Science Research Conference (TSRC), held in Montreal on September 12-15, 1999, was attended by about 300 scientists; 82 papers and 11 posters were presented. A keynote theme of the Conference was addressed in the Symposium on “Genetics and the Future of Tobacco”, with four contributions focussing on the effects of modern gene technology on tobacco growing, possible uses of transgenic tobacco and the main areas of research in this field, as well as consumer acceptance of transgenic products and regulatory issues, respectively.
Reaction of Indicator Tobacco Cultivars to Races of Pseudomonas syringaepv. tabaciTox+
Authors: Cole DL , Mapuranga N
Published: July 2016

Three races of Pseudomonas syringaepv. tabaciTox+ (wildfire) (races 0, 1 and 2) and two races of Tox- (angular leaf spot) (races 1 and 2) have been confirmed on tobacco in Zimbabwe (Zim). Very few cultivars with no resistance to Ps. syringaepv. tabaci are grown commercially and race 0 has not been isolated since 1996. Because we no longer have a viable culture of race 0, we obtained an isolate of race 0 from Kentucky (0 KY), USA in January 2000. We included this isolate in race tests on standard indicator cultivars K E1 (susceptible to all races), KM 10 (resistance to race 0 derived from Nicotianalongiflora), WZ (resistance to races 0 and 1 derived from N. rustica) and a hybrid, K 35 (resistance to races 0 and 0 and 1 derived from N. longiflora and N. rustica respectively). Two leaves on 10-week-old seedlings were inoculated with a bacterial suspension (106 colony forming units [cfu] per mL) by spraying selected areas until just watersoaked and incubating the plants at 28 C and 70% RH for 10 d. The reaction to race 0, measured as lesion diameter, was different from that previously obtained with race 0 (Zim). Races 0 and 1 (Zim) are avirulent on WZ but race 0 (KY) was virulent. Further isolates of race 0 were received from Maryland (MD) and Tennessee (TN). The TN isolates overcame resistance derived from N. longiflora and N. rustica, except where both sets of genes were present in the same cultivar. Reactions have been variable with the race 0 (MD) isolate suggesting it is a mixed culture. We conclude that there are at least four races of Ps. syringaepv. tabaciTox+ worldwide and race 0 (KY) should be designated race 3. On all cultivars, race 2 consistently caused the largest lesions.
Biochemical Changes in β-Cryptogein-Elicited Tobacco: A possible Basis of Acquired Resistance
Authors: Edreva A , Blancard D , Delon R , Bonnet P , Ricci P
Published: July 2016

β-Cryptogein, a proteinaceous elicitor from the phytopathogenic fungus Phytophthoracryptogea, is known to induce leaf necrosis in tobacco and non-specific resistance (expressed in the perinecrotic leaf area) against a wide range of tobacco pathogens. To reveal mechanisms underlying the acquired resistance, biochemical changes in leaves of β-cryptogein-elicited tobacco were followed three, five and ten days after elicitation. The activities of peroxidase, β-1,3-glucanase and β-glucosidase, as well as the patterns of acidic pathogenesis-related (PR)-proteins were determined. The protected part (perinecrotic area) and the non-protected part (distant extra-perinecrotic area) of leaves of β-cryptogein-stem treated tobacco (cv. Xanthin.c.) were analyzed. Leaves of water-stem treated tobacco served as controls. It was shown that in the protected leaf part β-cryptogein caused significant metabolic shifts early after elicitation, persisting during the whole period studied. An important increase of peroxidase and β-1,3-glucanase activity was recorded. PR-protein components appeared that were absent in the controls. There were negligible changes in β-glucosidase activity. In the non-protected leaf part late and non-significant changes occurred. Taking into account the antimicrobial, regulatory and structure-modifying properties of the biochemical components studied, it may be admitted that β-cryptogein elicited the development of a hostile environment, i.e. a potential for plant resistance against subsequent pathogen invasion.
Handling and Curing Characteristics of Cut-Strip Tobacco. Part 2: Effect of Yellowing Time and Drying Potential
Authors: Johnson WH , Weeks WW
Published: July 2016

This paper presents Part 2 of a study on comparative handling and curing characteristics of cut-strip vs. whole leaf tobacco. Part 1 considered the effect of leaf size (cut-strip size vs. whole leaf), packing density and mode of leaf orientation on cured leaf chemistry and leaf quality; whereas, the present study considers further the effect of leaf form, two yellowing times and two drying potentials during yellowing. Results showed that leaf chemistry and quality were quite similar for cut-strip (15.2 × 22.9 cm) and whole leaf. Insignificant differences were noted for cured leaf starch and sugars, although slightly lower levels of alkaloids (significant at the 0.01 level) were observed for cut strip. Curing treatments significantly affected leaf chemistry. Increased yellowing time resulted in lower levels of starch and higher levels of sugar. Sugars were also higher for tobacco yellowed under the higher drying potential. The two forms of leaf responded similarly to different curing schedules (i.e. no interaction of leaf form with schedule). Also, government grade and price data were essentially unaffected by leaf form or curing schedule over the range of variables tested. Cured leaf starch was abnormally high on the average for both leaf forms. Interestingly, starch levels were lower when intact tobacco was bulk-cured in racks rather than box cured (6.35% vs. 9.02%). Since curing schedules were similar, air velocity in the two curing methods might be a factor. Also the cured leaf starch content was about 56% lower for tobacco produced at the Oxford Tobacco Research Station (in a secondary study) than at the Central Crops Research Station. It is postulated that carbohydrate and nitrogen metabolism during growth and maturation might be affected by excess rainfall events and/or nitrogen availability, with subsequent effects on starch-to-sugar conversion during curing.
Wild Nicotiana Species as a Source of Cytoplasmic Male Sterility in Nicotianatabacum
Authors: Nikova V , Vladova R
Published: July 2016

The results of our experiments executed to obtain tobacco male sterile lines through interspecific hybridization are summarized. Ten wild species from the genus Nicotiana: N. excelsior (exc), N. amplexicaulis (amp), N. rustica (rus), Nicotianaglauca (gla), N. velutina (vel), N. benthamiana (ben), N. maritima (mar), N. paniculata (pan), N. longiflora (lon) and N. africana (afr) were used as cytoplasmic donors and N. tabacum, cv. HarmanliiskaBasma (HB) as a donor of the nucleus. Genetic effects of cytoplasmic-nuclear interaction of the studied species are discussed. Our results suggested that cytoplasmic male sterility (CMS) was expressed when the cytoplasms of the above mentioned wild Nicotiana species were combined with the nucleus of N. tabacum. The 10 sources of CMS obtained in tobacco were characterized by altered flower phenotypes. Flowers are classified into types according the stamen, pistil and corolla modification. All these CMS sources were backcrossed to Oriental tobaccos, cvs. Tekne, Nevrokop B-12, Kroumovgrad 90 and Djebel 576, to develop corresponding CMS lines. The investigated cytoplasms produced compete male sterility in all those cultivars. The CMS lines preserved flower types, specific for every “sterile” cytoplasm. The extent of male organ modifications varied from apparently normal (but pollenless) stamens in CMS (pan), (afr), some plants of (vel) (mar) through different degrees of malformations (shriveled anther on shortened filaments (lon), pinnate-like anthers on filaments of normal length (amp), petal - (ben), pistil- or stigma-like structures (rus), (gla)) to lack of male reproductive organs in (exc) and in some plants of (vel), (mar), (rus) and (gla). Most of the above mentioned cytoplasms had normal female gametophyte and good seed productivity. Alterations of the pistils were observed in CMS (rus), (exc) and (ben) causing reduction of the seed set. Electrophoresis of seed proteins of the tobacco cultivars and their CMS lines also suggested that the nuclei of wild species was entirely displaced by the nucleus of N. tabacum. CMS lines with cytoplasms of N. velutina, N. maritima, N. paniculata, N. longiflora and N. amplexicaulis were selected as suitable for seed production in tobacco.
Editorial
Authors: Heller WD , Scherer G
Published: July 2016

In this issue of BeitraegezurTabakforschung International/Contributions to Tobacco Research, we publish a ‘Letter to the Editor’ written by R. Baker (p. 360). This letter is a reply to a commentary by S. Shatenstein published in Tobacco Control (11, 174-175, 2002) which provided a critique of a review written by Baker on standards for smoking-machine methodology which appeared in this journal (Beitr. Tabakforsch. Int. 20, 23-41, 2002). The reason why we as editors of Beitraege have decided to publish the letter is simple, the editors of Tobacco Control, the appropriate place for publication, did not allow its publication. In the interest of a fair and scientific discussion of this matter, we think that an author whose paper is criticized publicly should have the chance to reply. However, we regret that Shatenstein's critique and Baker's reply might reach totally different readers.
Potassium Organic Salts as Burn Additives in Cigarettes
Authors: Liu C , Parry A
Published: July 2016

Three potassium salts of organic acids, namely malate, citrate and tartrate, have been sprayed onto flue-cured blend tobacco and subsequently tested for their performance as burn additives in cigarettes. In one experiment where potassium malate was added to vary the final tobacco potassium from ca. 3.1% to 8.3% (wet weight), an almost linearly reduction in puff temperature was measured. This was accompanied by a gradual increase in the cigarette's pressure drop. In another set of experiments where the final tobacco potassium contents were increased to ca. 5.1%, the three potassium salts showed almost equal reduction in the mainstream nicotine-free-dry-particulate-matter (NFDPM) at 32-35%, nicotine at 25-32% and carbon monoxide at 24-35%. Puff number showed ca. 23% increase with malate, 13% with citrate and almost unchanged for tartrate. Evidence of melting and coating by potassium malate was discovered in cigarette ash by scanning electron microscopy (SEM). This contributed to a noticeable change in ash morphology: small ash particles appeared to be coated and more tightly bonded together by the melt. This phenomenon was thought to be able to restrict the airflow during puffing, hence causing the measured increase in pressure drop, and the reductions in puff temperature, NFDPM, nicotine and carbon monoxide.
The Composition of Cigarette Smoke: Problems with Lists of Tumorigens
Authors: Rodgman A
Published: July 2016

Since the mid-1960s, various investigators, agencies, and institutions have disseminated lists of cigarette mainstream smoke (MSS) components reported to be tumorigenic on the basis of laboratory bioassays conducted under conditions significantly different from those encountered by the smoker during exposure to the components in the cigarette MSS aerosol. Since 1990, numerous lists of cigarette MSS components, defined as significant tumorigens, have been compiled by American Health Foundation personnel, Occupational Safety and Health Administration (OSHA), Fowles and Bates, and R.J. Reynolds R&D personnel. The purpose of most of the reports was to define human risk assessment and to dissuade smokers from smoking. Various investigators and agencies have frequently cited the earlier and/or the more recent lists of tumorigenic entities. The recent compilations, involving nearly 80 MSS components, suffer from serious deficiencies including: a) Use of per cigarette delivery ranges for specified components which often include analytical data from cigarettes manufactured in the 1950s and 1960s which are not comparable to lower-'tar’ yield cigarettes manufactured since the mid-1970s. b) Absence of standard analytical procedures for most of the listed components. c) Methodological considerations regarding bioassays used to determine tumorigenicity of the listed MSS components. d) Difficulty in extrapolating in vivo bioassay data obtained by non-inhalation modes of administration of a single compound to the human smoking situation involving inhalation of a complex aerosol containing that compound. e) Inhalation data inadequacies regarding the tumorigenicity of many of the components. f) Several tobacco smoke components are listed despite the fact their presence has not been confirmed, their MSS level has not been defined, or their MSS level is no longer relevant. g) Insufficient consideration of inhibitors of tumorigenesis and mutagenesis found in MSS. h) Difficulty in extrapolation of inhibition/anticarcinogenesis/antimutagenesis observed in a one-on-one in vivo situation to the complex MSS aerosol situation. j) Alternate exposures to many of the listed smoke components. k) Discrepancies among the lists. l) Discrepancies within the lists.A more appropriate use of the listing process is the identification of potential chemical targets for removal from, or inhibition in cigarette MSS.
Role of Oxides of Nitrogen in Tobacco-Specific Nitrosamine Formation in Flue-Cured Tobacco
Authors: Nestor TB , Gentry JS , Riddick MG , Conner BT , Peele DM , Edwards ME
Published: July 2016

Tobacco is known to contain a class of nitrosamines known as tobacco-specific nitrosamines or TSNA. Nitrosation of naturally occurring tobacco alkaloids is commonly accepted as the mechanism of TSNA formation in tobacco. Because green and freshly harvested tobaccos are virtually free of TSNA, formation and accumulation of TSNA are generally considered to occur during the curing process. Most recent hypotheses have focused on microbial reduction of nitrate to nitrite and other oxides of nitrogen (NOcompounds) that react with tobacco alkaloids to form TSNA during curing. This natural microbial process remains the prevalent hypothesis for TSNA formation in burley and other air-cured tobaccos. However, a different mechanism for the formation of TSNA in flue-cured tobacco, independent of microbial activity, is documented in this paper. It is common practice to flue-cure Virginia or blonde tobacco in bulk barns that incorporate forced air ventilation and temperature control. For the last thirty-five years, many modern bulk barns in North America generally have used liquid propane gas (LPG) with direct-fired burners that exhaust combustion gases directly into the barn where the tobacco is exposed to those gases. Our studies indicate that LPG combustion by-products in the exhaust stream, namely NO, react with naturally occurring tobacco alkaloids to form TSNA. Heat exchange curing methods preclude exposure of the tobacco to combustion gases and by-products, thereby eliminating this significant source of TSNA formation, without degrading leaf quality or smoking character. Research findings from 1998 and 1999 are presented to demonstrate the role of NOgases in TSNA formation and the significance of direct-fired curing as a primary source of TSNA formation in flue-cured tobacco. Also, data from an extensive barn conversion program in 2000, which resulted in a 94% average reduction in TSNA levels in cured flue-cured leaf, are presented.
Application of Nanoparticle Iron Oxide in Cigarette for Simultaneous CO and NO Removal in the Mainstream Smoke
Authors: Li P , Rasouli F , Hajaligol MR
Published: July 2016

Based on the unique temperature and oxygen profiles in a burning cigarette, a novel approach is proposed in this paper to use a single oxidant/catalyst in the cigarette filler for simultaneous removal of carbon monoxide (CO) and nitric oxide (NO) in mainstream smoke. A nanoparticle iron oxide is identified as a very active material for this application due to its multiple functions as a CO catalyst, as a CO oxidant, and in its reduced forms as a NO catalyst. The multiple functions of the nanoparticle iron oxide are characterized in a flow tube reactor and the working mechanisms of these multiple functions for CO and NO removal in a burning cigarette are explained. The effect of smoke condensate on the catalyst are examined and discussed. The advantage of in situ generation of the catalyst during the cigarette burning process is illustrated. The test results of nanoparticle iron oxide for CO and NO removal in cigarettes are presented.
Diffusion of Moisture in a Cigarette Tobacco Column at Room Conditions
Authors: Oh IH , Jheong GR
Published: July 2016

The moisture content of cigarettes has a significant impact on the shelf life and the taste of the products as well as various physical properties of cigarettes including loose ends, burning rate, hardness, and pressure drop. To prepare better products it would be helpful to develop proper mathematical models for the simulation of moisture diffusion characteristic dynamics in a cigarette. In this work, four mathematical models have been developed with appropriate assumptions adequate to analyze the dynamics of moisture diffusion in cigarettes. The simulation of the derived models was also carried out in this work. When the theoretical values produced from each model were compared with the corresponding experimental data, it was found that three models (I-II, II, III) can be used to explain the behavior of moisture in cigarettes. Convective mass transfer coefficients and effective moisture diffusivities that fit best were obtained by a regression analysis of the model using the experimental values. The simulation of the models revealed that there is no significant positional dependence of moisture content inside a tobacco column because most of the moisture dries out radially through the cigarette wrapper. The drying rate of moisture in a tobacco column is rarely affected by effective moisture diffusivity, but strongly influenced by convective mass transfer. To prevent quality deterioration of the cigarettes during long-term storage, it is concluded that improvement of the cigarette wrapper and air tightness of the package, which are directly related to the convective mass transfer, is very important.
Analysis of Sidestream Smoke VOCs and Characterization of their Odor Profiles by VOC Preconcentrator-GC-O Techniques
Authors: Higashi N , Shikata H , Shimoda M , Hayakawa I
Published: July 2016

Various techniques have been employed in the analysis of volatile organic compounds (VOCs). However, these techniques are insufficient for the precise analysis of tobacco smoke VOCs because of the complexity of the operating system, system instability, or poor sensitivity. To overcome these problems, a combined system of VOC preconcentrator, gas chromatograph, and olfactometer has been developed. The performance of this new system was evaluated in the analysis of VOCs in tobacco smoke and applied to the odor profiling of sidestream smoke (SSS) that has not been sufficiently investigated in the past.

A VOC sample in a gas-sampling bag was injected into a gas chromatograph through a preconcentrator, where it was concentrated, dehydrated, and cryo-focused. Separated VOCs were introduced into a mass spectrometer (for qualitative and quantitative analysis) and a sniffing port (for odor profiling) by a splitting device. In addition to the conventional Gas Chromatography-Olfactometry (GC-O) technique that was used for describing the odor quality of each compound, the odor intensity was estimated based on the dilution ratio of the sample, Aroma Direct Dilution Analysis (ADDA). Also, the contribution of each VOC to the overall SSS odor was estimated by sensory evaluation.

This system permitted adequate characterization of the VOCs. The reproducibility of quantification was also good enough with Coefficient of Variation (CV) values less than about 5% (n = 5). With the GC-O technique, we obtained an SSS odor profile composed of over 30 odorants. ADDA indicated that seven odorants were sufficient to characterize SSS odor. In addition, the omit-test revealed that three odor attributes, (‘metallic’, ‘potato-like’, and ‘popcorn-like’) were most important for the characterization of SSS odor.
The UK Smoke Constituents Testing Study. Summary of Results and Comparison with Other Studies
Authors: Gregg E , Hill C , Hollywood M , Kearney M , McLaughlin D , McAdam K , Williams M , Purkis S
Published: July 2016

At the request of the UK Department of Health, samples of 25 commercial UK cigarette brands were provided to LGC Ltd a for smoke analysis. The brands reflected a high market share (58% in July 2001) and included a wide range of blend and product styles manufactured and imported into the UK.= 0.76), suggesting a minor role of other design features on constituents yield variability. This was confirmed by the application of multiple regression analysis to the data. A subset of five brands, retested at another laboratory, gave between-laboratory differences in mean constituent yields of as much as 2.5-fold. Consideration of these results, other likely sources of analytical variation in this study and a review of other studies, clearly indicates that any tolerance values to be associated with individual smoke constituent measurements will be greater than those for NFDPM, and in some cases, much greater. Consistent with the reported results from other large studies it is concluded that, under ISO smoking conditions, smoke constituent yields are largely predictable, if NFDPM and CO yields are known, for a standard cigarette. Given these observations and the likely limitations of analytical determination, the need for routine measurement of smoke constituent yields, other than NFDPM, nicotine or CO, on standard cigarettes, is questionable.
An Experimental and Numerical Analysis of Puff Hydrodynamics
Authors: Saidi MS , Hajaligol MR , Rasouli F
Published: July 2016

The permeability of a tobacco rod in a cigarette increases as it converts into char and ash in the coal. The hot coal introduces a significant resistance to the air flow when air passes through. Through a series of experiments, the cigarette burn line and burn rate, the centerline temperature, and the pressure drop were measured for continuous puffing conditions. The gas viscosity was calculated from the temperature distribution inside the cigarette and applying Sutherland's law. Then, the experimental setup was mathematically modeled from a commercially available CFD (Computational Fluid Dynamics) code and, by matching the numerical and experimental results, the changes in coal and filter permeability during puffing were estimated. The numerical simulation successfully reproduced the results of experiments on the air flow through the coal, ventilation holes and paper wrapper.
Measurement of Air Flow Outside a Burning Cigarette during a Puff using Particle Image Velocimetry
Authors: Nagao A , Miura K , Kitao S , Horio M
Published: July 2016

In order to clarify the mechanism for the generation of cigarette smoke, the combustion mechanism of a burning cigarette during a puff was investigated by focusing on air transfer. In particular, the air flow distribution outside a burning cigarette was observed and related to the aerodynamic effects of the cigarette paper and the puffing rate. The air flow rate was measured by Particle Image Velocimetry (PIV), using olive oil droplets as the tracer particles. It was found that air does not flow into the tip of the burning cigarette and that the air flow was concentrated at the region -2 to 2 mm around the cigarette paper char-line. This behavior was independent of the cigarette paper basis weight. When the puffing rate was changed from 2.5 to 35 mL/s, the air flow was concentrated at a region close to the cigarette paper char-line and the maximum velocity around the cigarette paper char-line increased with the puffing rate.
Agronomic Performance of Flue-Cured Tobacco F1 Hybrids Obtained with Different Sources of Male Sterile Cytoplasm
Authors: Berbec A , Laskowska D
Published: July 2016

Four cytoplasmic male sterile (cms) F1flue-cured hybrids cv. Wiaelica × cv. Virginia Golta (VG), the male fertile analogue and the parental varieties were tested at two locations in Poland in a replicated field trial. The cms sources in the hybrids wereN. suaveolens,N. amplexicaulis,N. bigeloviiand aN. tabacumcms mutant. Under the slight to moderate pressure from black root rot present at the trial sites the hybrids showed a moderate tolerance of the disease characteristic of VG as opposed to medium strong susceptibility of Wislica. Apart from the effect of black root rot tolerance the vegetative vigor of the hybrids (plant height, leaf size, earliness) was affected by cytoplasm source. The F1hybrid withN. suaveolens cytoplasm flowered approximately three days later than the remaining hybrids. Of the cms hybrids tested cmsN. bigelovii produced the tallest plants with largest mid-position leaves. Yields of cured leaves were largely influenced by black root rot and were generally higher in VG and in the hybrids than in Wislica. Leaf yields and curability were generally little affected by cms source under low pressure from black root rot. At the site with a relatively high level of black root rot infestation the yields of cmsN. suaveolens were slightly lower but the percentage of light grades slightly higher compared to those of other cms hybrids. CmsN. suaveolens was the best hybrid in terms of money returns at the low black root rot field but it was the poorest hybrid performer under high pressure from the disease. Contents of nitrogen, sugars, nicotine and ash was little affected by source of cms. There was an increased incidence of potato virus Y (PVY) and white spots in cmsN. suaveolens and, to a lesser extent, in cmsN. bigelovii as compared to the remaining disease-free entries.
Measurement of Gas Diffusion Capacity of Cigarette Papers
Authors: Norman AB , Caudle JC , Henderson CW
Published: July 2016

Apparatus suitable for measuring gas diffusion capacity of cigarette paper was assembled and evaluated. The apparatus provides semi-automated means for measuring the concentration of carbon dioxide diffusing through a small area of the paper, and computation of a paper thickness-dependent diffusion capacity of the sample. Measurements are rapid and can be made in about 30 s. Diffusion capacity measurements were repeatable and reproducible to within about 1%. Variability of the diffusion capacity values was much lower than that observed for permeability measurements. For these reasons, the apparatus is useful for quality assessment and research applications. Diffusion capacity was measured for cigarette papers of inherent permeability ranging from 6 to 62 cm/min. As expected from prevailing theory, the diffusion capacity values generally increased with permeability. The diffusion capacity measured for electrostatically perforated papers was only slightly higher (about 6-11%) than the unperforated base paper despite large increases in permeability. This result indicates that diffusion capacity is governed by small pores in the paper. The apparatus is capable of measuring banded areas of papers designed for reduced ignition propensity. Diffusion capacity values for banded areas were lower than those of non-banded paper of similar permeability, suggesting that the band material preferentially occludes small pores in the paper.
Smoking Behavior: How Close to the Tipping Do Consumers Actually Smoke?
Authors: St. Charles FK , Kabbani AA , Ogden MW
Published: July 2016

When smoked by the Federal Trade Commission (FTC) method, the standard butt length for filtered cigarettes is specified as tipping plus 3 mm. One of the criticisms of this standard is that the tipping overlap hides some of the tobacco column and that consumers actually smoke cigarettes past the tipping.

The objective of this study was to determine how consumers actually smoke their usual brand when smoking in their everyday environment. A portable device was designed to collect and preserve cigarettes from consumers after smoking. In use, the smoldering cigarette is dropped into the device and it is closed. Upon closing, the cigarette is extinguished, the mouth end of the filter is cut and separated for further analysis, and the date and time are recorded.

Fifty adult smokers per brand were recruited across 5 US cities (10 smokers/city). A wide range of brands was studied: menthol and non-menthol, 1 mg to 18 mg FTC ‘tar’ yield, 17 to 25 mm circumference, and both 85 and 100 mm lengths. A total of 10528 cigarettes from 803 subjects covering 17 brands was measured.

The subjects were provided with one pack of their usual brand, as well as a collection device, and were instructed on how to use the device. The devices were collected on subsequent days. The cigarettes were then removed and the distance from the tipping to the char line was measured. The overall median butt length was tipping plus 6.7 mm with an overall average of tipping plus 8.4 mm. There was no significant effect of FTC ‘tar’ yield on either mean (p = 0.72) or median (p = 0.92) butt length.
A Simulation Study of Self-Extinguishing Cigarettes
Authors: Eitzinger B
Published: July 2016

In some parts of the USA and in Canada smouldering cigarettes are required to extinguish if placed on a certain number of layers of filter paper. This is usually achieved by the use of bands on the cigarette paper, which reduce oxygen diffusion into the cigarette. From a smoker's perspective, however, it is desirable that a cigarette does not extinguish if left to smoulder, for example, in an ash tray. To facilitate the design of papers for such cigarettes the influence of various cigarette parameters on self-extinguishment is investigated by numerical simulation of a one-dimensional cigarette model, which describes the main thermodynamic behaviour of smouldering cigarettes. The tobacco density, the tobacco heat capacity, the width of the bands on the cigarette paper and the heat released during combustion are chosen as parameters whose influence on the required oxygen diffusion constant of the bands on the cigarette paper is investigated. As these parameters are subject to a certain variation, it is assumed that the parameters are independently normally distributed. Based on this assumption the probability that a cigarette with given mean parameter values will extinguish, is calculated numerically.

The results show that the admissible range of diffusion constants for the bands on the cigarette paper is in general quite small and it is reduced even further if statistical variations of the cigarette parameters are considered.

The results provide guidelines for the appropriate choice of the diffusion constant of the bands on the cigarette paper such that the cigarettes comply with legal requirements and do not extinguish during normal smoking.
Low-Temperature Oxidation of CO in Smoke: A Review
Authors: Dyakonov AJ , Robinson EA
Published: July 2016

The low-temperature catalytic oxidation of CO has been reviewed, targeting its possible application to cigarette smoke. The treatment of CO in smoke by using a filter-packed catalyst is extremely complicated by the presence of a variety of chemically active gaseous compounds, a particulate phase, the high velocity of pulsing smoke flow, and ambient temperature. The relevant mechanisms of catalysis and the catalyst preparation variables that could help to overcome these problems are considered. Possible contributors to the overall kinetics that must include variety of diffusion processes were briefly discussed. The chemisorption of O2, CO and CO2 on Pd, Pt and Au and on partially reducible supports, surface reactions and oscillations of the CO oxidation rate were analyzed. The effects of the surface structure and electronic properties of the catalyst support, preparation conditions and presence of a second transition metal on the projected CO oxidation activity of the catalysts in smoke are also discussed. The reviewed catalyst preparation approaches can solve the low-temperature catalyst activity problem. However, more work is required to stabilize this activity of an air-exposed catalyst to provide a necessary shelf life for a cigarette. The greatest challenge seems to be a particular phase - exclusive selectivity that would not contradict with the necessary fast diffusion of gases through the catalyst pores.
Study of Growing Flue-cured Tobacco in Croatia under Various Conditions of Irrigation and Nitrogen Nutrition
Authors: Cavlek M , Tursic I , Cosic T
Published: July 2016

Three field experiments were conducted at the experimental station of the Tobacco Institute Zagreb in Pitomaca during the years 1990 and 1992, 1993-1996 and 1999-2000 to determine the effects of irrigation at different soil moisture levels [40-100%, 60-100%, 80-100% of plant available water, (PAW)], of different starting times of irrigation (vegetative phase, early flowering stage, continuously), and of irrigation combined with nitrogen nutrition (0, 20, 40, 60 kg/ha N) on the yields and quality of flue-cured tobacco. The first two experiments involved block methods, the third involved the split-plot method.

In the first experiment, irrigation led to an increase in yield (3-38%), in price/kg (15-69%) and in reducing sugar content (18-89%) and a reduction of nicotine content (20-39%) in the flue-cured leaves. Additional irrigation at the early flowering stage and constant maintenance of soil moisture at a higher level resulted in somewhat lower yields but better visually estimated tobacco quality and, as expected, had a marked influence on the contents of nicotine and reducing sugars.

In the second experiment, irrigated tobacco gave higher yields in two of the four trial years, which were significant in 1995 (13-21%), higher reducing sugar levels in 1994 (20-34%) and a marked reduction of nicotine content in cured leaves in all years (11-56%). Under conditions identical with or similar to those used in this research, irrigation may be started at the early flowering stage.

In the third experiment, in both years irrigated tobacco showed significantly higher yields, price/kg and reducing sugar levels and significantly lower nicotine content. Averaging the two years indicated increases of 17%, 12% and 26% and a decrease of 29%, respectively. Higher amounts of nitrogen fertilizer promoted yield (up to 32%) and nicotine content (up to 76%), while decreasing reducing sugar levels (by up to 52%). Also, the price/kg of tobacco fertilized with more than 20 kg/ha of nitrogen dropped by as much as 26%.
The Relation Between the Quantity of Ammonium Compounds in Tobacco and the Nitrogen Monoxide (NO) Levels in the Smoke of Cigarettes Marketed in the Netherlands
Authors: van Amsterdam JGC , Brunt TM , Verlaan APJ , Cleven RFMJ , Opperhuizen A , Vleeming W
Published: July 2016

It has been suggested that ammonium compounds in tobacco generate nitrogen monoxide (NO) in cigarette smoke. This causes the smoke to retain the broncho-dilatory properties of the tobacco, which leads to an increased uptake of nicotine and thus to a potentially higher addiction to tobacco. The objective of this study was to ascertain putative correlations among the concentration of ammonium compounds in whole tobacco and the concentration of NO in mainstream smoke.

In 98 different cigarette brands marketed in the Netherlands, positive correlations were found between ‘tar’ and nicotine values (coefficient of variation, R2 = 0.95), and between ‘tar’ and NO concentration (R2 = 0.47). The quantity of ammonium compounds in tobacco (expressed as the amount of NH4+ present) varied, however, from 0.1 to 3.3 mg per gram of tobacco and was not associated with any of the parameters investigated here. In addition, five cigarette types were compared with respect to the levels of ammonium-compounds in the tobacco, the concentration of NO in the smoke and ‘tar’/nicotine ratio. The concentration of NO in the smoke from light menthol and light cigarettes (‘tar’ content < 9 mg/cig) was significantly lower than that from their regular equivalents (‘tar’ content > 9 mg/cig). As expected, the ‘tar’/nicotine ratio of regular cigarettes was significantly higher than the ratio in light cigarettes.

This study shows that the whole tobacco in the various cigarette brands differed in the amount of ammonium compounds it contained, but these amounts bore no relation to the level of NO and the level of nicotine and ‘tar’ in the smoke. Other factors that affect the burning process, such as nitrate content and product design may have made the association between ammonium compounds in tobacco and the level of NO in mainstream smoke less clear.
A Modelling Approach to Develop Machine Smoking Protocols Reflecting Human Puffing Behaviour for Conventional Cigarettes
Authors: Urban HJ , Gomm W , Schorop M
Published: July 2016

Our objective was to develop machine-smoking protocols (i.e. puff volume, puff duration and puff frequency) reflecting the distribution of human smoking behaviour as a complement to the International Standard (ISO) protocol. For this purpose, a modelling approach based on smoking topography and excretion data of urinary nicotine metabolites from clinical studies in the UK and Japan was used.

Three smoking protocols (LOW, MEDIUM and HIGH) were based on the 10th percentile, the mean and the 90th percentile of the puff volumes obtained from topography data. The corresponding puff durations were estimated by linear regression analysis of the puff duration/puff volume relationship. Finally, puff frequency was estimated using a predictive model assuming that the nicotine yield is a linear function (i.e. proportional) to the amount of air actually drawn through the burning part of the cigarette. This approach was termed ‘nicotine proportion method‘ where the puff frequency is changed iteratively until it equals the corresponding nicotine uptake measured in human smokers during a clinical study. The assumption was verified by measuring the nicotine yield in the laboratory on three modelled protocols for four conventional cigarettes. In 10 out of 12 cases, a very good agreement was observed between the estimated nicotine yields obtained with our modelling approach and the measured nicotine yields obtained from smoking machines in the laboratory.

Although smoking virtually identical cigarettes, smoking protocols based on topography and excretion data of urinary nicotine metabolites from the UK clinical study were different than those based on data from the study performed in Japan. This may be explained by different smoking behaviour between these two populations of smokers.
Isolation, Fractionation, and Identification of Sucrose Esters from Various Oriental Tobaccos Employing Supercritical Fluids
Authors: Ashraf-Khorassani M , Nazem N , Taylor LT , Coleman WM
Published: July 2016

Isolation, fractionation, and identification of sucrose esters from aged oriental tobacco employing supercritical fluids have been completed. Underivatized sucrose ester-rich extracts were obtained using supercritical CO2 at densities greater than 0.73 g/mL. Lower density CO2 provided extracts with notable amounts of tobacco derived material; yet, no detectable sucrose ester content. Preparative supercritical fluid chromatography (SFC) provided for an additional purification of the sucrose ester-enriched fraction after column optimization. Structural assignments of the SFC fractions were facilitated using gas chromatography/mass spectrometry (GC/MS) accompanied by N, O-bis(trimethylsilyl)trifluoroacetamide-dimethylformamide (BSTFA-DMF) derivatization of the free hydroxyl groups and high performance-liquid chromatography/mass spectrometry (HPLC/MS). From a relative quantitative perspective regardless of tobacco type, sucrose esters having an acetyl group on C6 of the glucose function (Group III) were in higher concentration compared to both the concentration observed for sucrose ester of Group I (acetyl group on C3 of fructose) and sucrose ester of Group II (no acetyl group on either glucose or fructose). Saturated fatty acid constituents were found to range from a maximum total of 18 carbons to a minimum total of 13 carbons. Unsaturated and isomeric fatty acid homologues were detected within the Group II sucrose ester.