rss_2.0Contributions to Tobacco & Nicotine Research FeedSciendo RSS Feed for Contributions to Tobacco & Nicotine Researchhttps://sciendo.com/journal/CTTRhttps://www.sciendo.comContributions to Tobacco & Nicotine Research 's Coverhttps://sciendo-parsed-data-feed.s3.eu-central-1.amazonaws.com/60f496cdf83c0e1a37b93dc9/cover-image.jpg?X-Amz-Algorithm=AWS4-HMAC-SHA256&X-Amz-Date=20211020T072527Z&X-Amz-SignedHeaders=host&X-Amz-Expires=604800&X-Amz-Credential=AKIA6AP2G7AKDOZOEZ7H%2F20211020%2Feu-central-1%2Fs3%2Faws4_request&X-Amz-Signature=e5ab769ed04a192fff675bbdc111a7bbd74f9d8bfd4c5f98856a763dfcb6f12a200300Editors’ Notehttps://sciendo.com/article/10.2478/cttr-2021-0010ARTICLE2021-10-01T00:00:00.000+00:00A Cross-Sectional Study of Electronic Cigarette Use Among Chinese Adult Populations in Four Cities of China. Part II. Puffing Topographyhttps://sciendo.com/article/10.2478/cttr-2021-0012<abstract> <title style='display:none'>Summary</title> <p>With the rapid popularity and increasing numbers of E-cigarette (EC) users, debates on possible health risks and regulation of EC products have attracted attention in public. As a useful means to help assessing the risks of EC consumers, puffing topography studies have come to be an important tool globally. In this paper, a cross-sectional epidemiological study on puffing topography of 511 EC consumers in four cities of China was conducted in January 2018. Data acquisition was based on a questionnaire and a Clinical Research Support System (CReSS) Pocket device for the smoking behavior recording. The results showed that EC consumers in the four cities were mainly young males, most of whom preferred tank systems with zero or low nicotine concentrations (1–5 mg/mL) in the liquid. The average puff volume, puff duration and inter-puff interval (IPI) were 87.2 mL, 1.97 s and 22.0 s, respectively. The factors that may have affected puffing topography such as product type, nicotine concentration, using time, smoking status and battery power were studied. The results suggest that the EC product type and the concentration of nicotine in EC liquids were the main factors that affected the puffing topography of the users. This study was the first study on the puff topography of Chinese EC consumers with a large number of participants. The results may not only help to more deeply understand smoking behavior and to better assess the potential risks for the EC users, but they may also supply useful information for the development of smoking machine regimes for ECs.</p> </abstract>ARTICLE2021-10-01T00:00:00.000+00:00Robustness of HPHC Reduction in THS 2.2 Aerosol Relative to 3R4F Reference Cigarette Smoke under Extreme Climatic Conditionshttps://sciendo.com/article/10.2478/cttr-2021-0008<abstract> <title style='display:none'>Summary</title> <p>In order to assess robustness for the reduction of harmful and potentially harmful constituent (HPHC) levels generated by the Tobacco Heating System 2.2 (THS 2.2), a heated tobacco product, we compared the aerosol of this product with mainstream smoke from the 3R4F reference cigarette under different conditions of temperature and humidity. The desired climatic conditions were achieved by using an air-conditioning system coupled with the smoking-machine housing. Two extreme climatic conditions were selected, representing a “Hot and Dry” climate (30 °C and 35% relative humidity RH) and a “Hot and Very Humid” climate (30 °C and 75% RH). In addition, aerosol and smoke were generated using the standard conditions recognized for smoking-machine analyses of tobacco products (22 °C and 60% RH), which were close to the climatic conditions defined for “Subtropical and Mediterranean” environments (25 °C and 60% RH). The experimental conditions were chosen to simulate the use of THS 2.2 and cigarettes under extreme conditions of temperature and humidity. HeatSticks and cigarettes taken from freshly opened packs were subjected to short-term conditioning from two to a few more days under the same experimental conditions. We analyzed 54 HPHCs in THS 2.2 aerosol and 3R4F cigarette smoke, generated in accordance with the Health Canada Intense (HCI) standard, using modified temperature and humidity conditions for sample conditioning and machine-smoking experiments. We used a volume-adjusted approach for comparing HPHC reductions across the different climatic conditions investigated. Although a single puffing regimen was used, the total puff volume recorded for the 3R4F cigarette smoke varied due to the influence of temperature and humidity on combustion rate, which justified the use of a volume-adjusted approach. Volume-adjusted yields were derived from HPHC yields expressed in mass-per-tobacco stick normalized per total puff volume.</p> <p>The results indicated that, regardless of the considered climatic conditions, the HPHC levels investigated in THS 2.2 aerosol were reduced by at least 90%, on average, when compared with the concentrations in 3R4F cigarette mainstream smoke. This confirmed the robustness in performance for THS 2.2 to deliver reduced levels of HPHCs under the extreme climatic conditions investigated in this study. In order to further characterize the robustness of these reductions, the lowest reduction performance achieved for individual HPHCs across all climatic conditions was used to define the threshold for a robust reduction. The majority of the 54 HPHCs investigated in THS 2.2 aerosol showed more than 90% reduction. Calculations derived from nicotine-adjusted yields also confirmed robust reductions for all investigated HPHCs. The small differences in absolute reduction between the volume- and nicotine-adjusted approaches were predominantly attributed to a combination of the differences in both nominal nicotine deliveries and total puff volumes between THS 2.2 and 3R4F cigarettes; however, this did not influence the determination of robustness. Our findings confirm the value of this approach for assessing the robustness of a product’s performance under different climatic conditions.</p> </abstract>ARTICLE2021-07-17T00:00:00.000+00:00A Cross-Sectional Study of Electronic Cigarette Use Among Chinese Adult Populations in Four Cities of China. Part I. Questionnaire Surveyhttps://sciendo.com/article/10.2478/cttr-2021-0011<abstract> <title style='display:none'>Summary</title> <p>The use of electronic cigarettes (ECs) has grown exponentially over the past few years in China. To obtain the basic information of Chinese EC users, a questionnaire survey was performed to collect the data that describe characteristics of study populations, including daily usage, consumption preference, and risk perception. Volunteers were recruited from Beijing, Shanghai, Guangzhou, and Shenzhen cities of China. In total, among the 511 participants that were included in the analysis, 491 participants (95%) used refillable ECs in the past 3 months. There was a strong association between EC use and traditional cigarette smoking. The majority of participants were dual users and the number of cigarettes smoked decreased with the use of ECs. After using an EC, 20.7% of conventional cigarette smokers attempted to quit smoking. Young people were the primary users across all geographic locations. Specifically, the daily usage for the participants who were 18–39 years old, was higher than those over 40 years old. The majority of participants (59.9%) preferred fruit flavors and 57.8% of them used 1–5 mg/mL nicotine-concentration liquids. Most EC users are motived to quit smoking, and 74.6% claimed that the ECs had no irritant effect on the oral cavity. A total of 50.5% of family members of the study participants reported an improvement of health status while the participants used ECs instead of traditional cigarettes. Overall, the results of this Chinese survey indicate that the per-day cigarette consumption of the dual users decreased whereas their proportion of smokers of low-“tar” cigarettes increased.</p> </abstract>ARTICLE2021-10-01T00:00:00.000+00:00Machine Vaping of Electronic Cigarettes - A Comparison of Puffing Regimeshttps://sciendo.com/article/10.2478/cttr-2021-0009<abstract> <title style='display:none'>Summary</title> <p>Several machine-based puffing regimes for collection of e-cigarette aerosol were evaluated with the objective of recommending one regime for standardization. The study involved a comparison of several candidate regimes for which puff volume, duration, interval, profile shape, and puff number were defined and varied. Testing was conducted at four laboratories using seven e-cigarette test products. Each participating laboratory generated and analyzed aerosol from the test products for glycerin, propylene glycol, water, and nicotine using the candidate regimes. Results were compared within each product’s data set to understand the impact of the regimes on product yield, consistency of results, and reliability of the testing equipment. Each of the regimes evaluated was determined to be fit for purpose for the range of products tested. Based on specific selection criteria, the recommended collection parameters are a square-shaped 55-mL puff of 3 s duration with a puff frequency of one puff every 30 s. Standardized reporting parameters include aerosol collected mass (ACM), puff count, and e-cigarette weight loss along with analyte yield on a per-puff basis and total-puffs basis.</p> </abstract>ARTICLE2021-07-17T00:00:00.000+00:00Evidence From the Scientific Assessment of Electronic Cigarettes and Their Role in Tobacco Harm Reductionhttps://sciendo.com/article/10.2478/cttr-2021-0007<abstract> <title style='display:none'>Summary</title> <p>While smoking remains a main global cause of preventable morbidity and mortality, a potential inflection point has arrived where it could become possible for non-combustible nicotine products to displace cigarettes and reduce risk for smokers who transition completely from smoking. These have proven consumer satisfaction and are now widely and increasingly available globally. One of the most prominent of these nicotine products are electronic cigarettes (ECs), which are used daily by millions of current and former smokers. The category is not without controversy as these products are not risk free and can cause nicotine dependence. The differing interpretation of science assessing ECs has transpired into inconsistent regulation and product standards, providing an environment for its fragmented manufacturing base which allows for variable product quality and in turn, product quality variability has impacted on how they are viewed. In this review, we assess published scientific evidence to evaluate whether, on balance, ECs fulfil a tobacco harm reduction role by reducing health risks relative to smoking and providing a viable alternative for smokers while having limited appeal to non-smokers.</p> </abstract>ARTICLE2021-05-20T00:00:00.000+00:00Impacts of Environmental Variations on Quality and Chemical Contents of Oriental Tobaccohttps://sciendo.com/article/10.2478/cttr-2021-0006<abstract> <title style='display:none'>Summary</title> <p>Basma tobaccos, in addition to Izmir and Samsun type tobaccos, are the most important high-quality oriental tobacco types grown in Turkey. This research was carried out to determine the effects of a variety of environmental conditions, in four locations on different altitudes on the yield as well as on nicotine, sugar and phenolic substances content. The plant material of the study included 21 Basma lines, which were selected according to their morphological differences and from genotypes separated by DNA fingerprint analysis, and four standard cultivars/lines (checks). The quality grade index of the genotypes was determined by the American grading method and chemical analyses were carried out using a high-performance liquid chromatography (HPLC) system. All the parameters investigated indicated that genotypes were significantly affected by the variation in environmental conditions. Organoleptic observations showed that the quality grade index of genotypes ranged from 24.17 to 100%, and the ERB-7, ERB-13, ERB-15, ERB-19 and ERB-38 lines had the best quality. Nicotine contents of tobacco lines were between 0.31 and 3.15% dry matter (DM). Glucose, fructose and their sum (reducing sugar) contents of genotypes ranged from 1.16 to 8.88% DM, from 2.60 to 8.66% DM and from 4.44 to 15.03% DM, respectively. The ERB-21 and ERB-30 lines are noteworthy tobacco types in terms of reducing sugar contents. The values of chlorogenic acid, one of the phenolic compounds, ranged from 40.67 to 1119.76 ppm, the values of rutin from 121.05 to 1021.53 ppm, and the sum of these two phenolic compounds was from 174.94 ppm to 2019.41 ppm. The effect of variations in the environment on the quality of Oriental tobacco can be clearly explained by the variations in the parameters.</p> </abstract>ARTICLE2021-04-20T00:00:00.000+00:00Analysis of Pyrolysis Characteristics and Kinetics of Cigar Tobacco and Flue-Cured Tobacco by TG-FTIRhttps://sciendo.com/article/10.2478/cttr-2021-0004<abstract> <title style='display:none'>Summary</title> <p>Investigation of the detailed pyrolysis characteristics of tobacco raw materials is important for the understanding of product design and consumption. In this work, pyrolysis characteristics and kinetic models of cigar filler tobacco (CFT), cigar wrapper tobacco (CWT), and flue-cured tobacco (FCT) were investigated by using a thermogravimetric analyzer coupled with Fourier-transform infrared spectroscopy (TG-FTIR). The pyrolysis of different tobacco samples could be divided into four stages based on the derivative thermogravimetric analysis (DTG) curves. Flue-cured tobacco underwent a marked decomposition process at lower temperatures (about 200 °C), while the thermal decomposition of cigar tobacco occurs at higher temperatures. During the pyrolysis process, evolved gases including H<sub>2</sub>O, CO<sub>2</sub>, CH<sub>4</sub>, CO, carbonyls, alcohols, phenols and aromatic compounds were detected by FTIR. CWT released more CO<sub>2</sub> than CFT, while the amount of CO<sub>2</sub>, CH<sub>4</sub>, CO and aromatic compounds released by flue-cured tobacco was lower than that of cigar tobacco. The pyrolysis kinetics of tobacco leaves were further analyzed and compared through the isoconversional FWO (Flynn-Wall-Ozawa) and KAS (Kissinger-Akahira-Sunose) methods. The activation energy of FCT (from 100.1 kJ mol<sup>−1</sup> to 192.1 kJ mol<sup>−1</sup>) was lower than that of CFT (from 207.36 kJ mol<sup>−1</sup> to 319.28 kJ mol<sup>−1</sup>) and CWT (from 160.40 kJ mol<sup>−1</sup> to 260.45 kJ mol<sup>−1</sup>). The thermal decomposition kinetics of different tobaccos were analyzed by M<sc>álek</sc> and C<sc>oats</sc>-R<sc>edfern</sc> methods.</p> </abstract>ARTICLE2021-04-20T00:00:00.000+00:00Editors’ Notehttps://sciendo.com/article/10.2478/cttr-2021-0001ARTICLE2021-04-20T00:00:00.000+00:00A Single-Center Evaluation of Environmental Emissions from ENDS and Combustible Cigaretteshttps://sciendo.com/article/10.2478/cttr-2021-0002<abstract> <title style='display:none'>Summary</title> <p>As the use of electronic nicotine delivery systems (ENDS) continues to increase, there is a need to evaluate their impact on indoor air quality. This study evaluated the differences in concentrations of volatile and particulate compounds (including formaldehyde, benzene, glycerol, propylene glycol, nicotine, and particulate matter) in secondhand vapor (SHV) after <italic>ad libitum</italic> subject vaping of cig-a-like ENDS, after-subject smoking of combustible cigarettes (CC), and after-subject non-smoking/non-vaping (blank) in an environmental test chamber. A single-center, open-label, parallel-group study was conducted. Seventy-one generally healthy smokers and vapers were randomized to one of six cohorts: Marlboro Gold Pack, Newport Box, Vuse non-menthol (14 mg nicotine/cartridge and 29 mg nicotine/cartridge), Vuse menthol (29 mg nicotine/cartridge), and market-sample ENDS. Concentrations of most secondhand constituents were similar after e-cigarette vaping and blank sessions. Constituent concentrations in SHV after ENDS use were significantly lower than in secondhand smoke (SHS) from CC, with the exception of glycerol and propylene glycol. Secondhand nicotine concentrations after ENDS use were 88–99% lower than after cigarette smoking. Emission factors between the three Vuse products were also similar with the exception of propylene glycol. Concentrations of some secondhand constituents after ENDS use were compared to existing indoor and occupational air quality guidelines and did not show potential to contribute appreciably to indoor air quality. These findings indicate that SHV from ENDS differs qualitatively and quantitatively from the SHS from CC.</p> </abstract>ARTICLE2021-04-20T00:00:00.000+00:00Evaluation of Presence or Absence of α-Tocopherol and α-Tocopheryl Acetate in Various E-Liquidshttps://sciendo.com/article/10.2478/cttr-2021-0005<abstract> <title style='display:none'>Summary</title> <p>The presence of α-tocopheryl acetate in e-liquids is linked to EVALI (Electronic Cigarette, or Vaping, product use-Associated Lung Injuries). Typical e-liquids containing flavors and nicotine have a glycerin/propylene glycol carrier and are highly unlikely to contain α-tocopherol or α-tocopheryl acetate. However, the e-liquids containing cannabinoids, most notably tetrahydrocannabinol (THC), may contain α-tocopherol or α-tocopheryl acetate for enhancing the solubility of THC which is a lipophilic compound. For the analysis of α-tocopherol and of α-tocopheryl acetate in e-liquids a new HPLC technique was adopted which has been developed for the analysis of these compounds in tobacco and cigarette smoke and was previously reported. Both UV and MS/MS (MRM mode) were used as detection procedure.</p> <p>Thirty four e-liquids containing different levels of nicotine were evaluated using this method. None of the e-liquids contained either α-tocopherol or α-tocopheryl acetate. Also, three e-liquids containing cannabidiol (CBD) were analyzed. Two of the CBD containing liquids did not contain α-tocopherol or α-tocopheryl acetate. However, one of these e-liquids did contain α-tocopherol, but the level was low at about 10 μg/g, which is lower than the level of α-tocopherol per smoke of one cigarette (ISO smoking), and significantly lower than the level of α-tocopherol in tobacco.</p> </abstract>ARTICLE2021-04-20T00:00:00.000+00:00Appropriate Mesh Size of Insect Screen for the Exclusion of the Cigarette Beetle, (F.)https://sciendo.com/article/10.2478/cttr-2021-0003<abstract> <title style='display:none'>Summary</title> <p>Insect screens are often used in tobacco facilities to exclude insect pests. Previous studies using laboratory cultures indicated that screens with openings smaller than 1.0 mm are adequate to prevent the passage of the cigarette beetle, <italic>Lasioderma serricorne</italic>. The beetles from natural populations are rather heterogeneous, and their body sizes may vary. Studies were conducted to confirm the relationship between mesh sizes and the body sizes of the cigarette beetles that can pass through the screens and to elucidate the size distribution of wild beetles. The results revealed that meshes can protect against beetles whose thorax width is larger than the openings in the mesh. Additionally, the widths of the prothoraxes of wild beetles captured in pheromone traps, which were generally considered to be male, ranged from 727–1070 μm (<italic>N</italic> = 169), and approximately 90% of the beetles had thoraxes that were narrower than 1000 μm. These data led to the conclusion that a 1.0 mm opening mesh is insufficient to protect against the cigarette beetle. Thus, Tyler standard #24 mesh (= US standard #25 mesh: 0.71 mm opening/sieve size) is recommended as an insect screen for tobacco facilities.</p> </abstract>ARTICLE2021-04-20T00:00:00.000+00:00Tobacco Production in Switzerlandhttps://sciendo.com/article/10.2478/cttr-2013-0666<abstract><title style='display:none'>Abstract</title><p>In Switzerland approximately 730 ha of tobacco are grown, mainly on small family farms. The main growing area is located in the French speaking part of the country, on altitudes ranging from 400 to 800 m above sea level. Approximately 93 % of the surface is planted with Burley and 7 % with Virginia. The cigarette manufacturers have to buy the whole crop of acceptable quality by law proportionally to their market share in Switzerland, in total approximately 1300-1500 tons per year. The buying organization, named SOTA (Societe cooperative pour l'achat du tabac indigene) has been created by the industry in 1930. It is responsible to buy and distribute the whole crop and finances a small research center with the aim to improve the quality. There is an agreement between the SOTA and the grower's organization FAPTA (Federation suisse des associations de planteurs de tabac) that limits the maximum surface to 730 ha. The price paid to the farmer is fixed by the government and is significantly higher than the world market price. The difference between the price paid to the farmer and the one paid by the industry is compensated by a specific fund which is under supervision of the custom and excise department. Because of several good crops, this system of subsidy became problematic. Therefore a new system of quota has been introduced for the 1997/1998 crop which limits the quantity of tobacco which can be delivered by each farmer.</p></abstract>ARTICLE2015-01-06T00:00:00.000+00:00Relationship Between Nicotine Dependence Scores and Nicotine, Cotinine, 3′-Hydroxycotinine and Nicotine Metabolite Ratio in Chinese Male Smokershttps://sciendo.com/article/10.2478/cttr-2020-0012<abstract><title style='display:none'>Summary</title><p>Smoking is mainly sustained by nicotine dependence (ND), which varies across ethnic groups principally due to genetic as well as environmental factors. The Fagerström Test for Nicotine Dependence (FTND) and biomarkers of tobacco exposure are two important approaches to assess ND. However, the relationship between ND and FTND of Chinese smokers has not been studied. The aim of this study was to assess the relationship between FTND scores and nicotine, cotinine, 3′-hydroxycotinine (3HC) and nicotine metabolite ratio (NMR, the concentration ratio of 3HC to cotinine) in Chinese smokers. FTND was carried out and general characteristics were collected using a self-administered smoking questionnaire with 289 smokers. Nicotine, cotinine and 3HC in urine were simultaneously determined by liquid chromatography–mass spectrometry/mass spectrometry (LC-MS/MS). The concentrations of nicotine, cotinine and 3HC in the urine of smokers with a high FTND score were higher than in the urine of those with a low FTND score. There were significant correlations between urinary biomarker and FTND scores. Except for FTND item 2 (difficulty to refrain), the other items showed significant associations with the urinary biomarkers. No relationship was found between the nicotine metabolite ratio (NMR, 3′-hydroxycotinine/cotinine) and FTND scores or general characteristics of the participants. In conclusion, biomarkers of tobacco exposure levels are significantly associated with FTND scores. However, FTND Item 2 and NMR were not found to be associated with nicotine dependence in Chinese smokers.</p></abstract>ARTICLE2020-12-31T00:00:00.000+00:00Inter-Laboratory Reproducibility and Interchangeability of 3R4F and 1R6F Reference Cigarettes in Mainstream Smoke Chemical Analysis and Toxicity Assayshttps://sciendo.com/article/10.2478/cttr-2020-0011<abstract><title style='display:none'>Summary</title><p>A new reference cigarette, 1R6F, produced by the Kentucky Tobacco Research and Development Center, has been manufactured as a substitute for the 3R4F reference cigarette because of a depletion of 3R4F stock. The purpose of the current study was to investigate the interchangeability of 1R6F and 3R4F by comparing the chemical and biological characteristics of the mainstream smoke and to assess the inter-laboratory reproducibility by comparing the results obtained in the current study with a previous report. We analyzed 45 priority chemicals required by Health Canada for regulatory reporting and assessed the toxicological effects of cigarette smoke using <italic>in vitro</italic> standard toxicological assays recommended by the Cooperation Centre for Scientific Research Relative to Tobacco (CORESTA) under the International Organization for Standardization (ISO) standard and intense smoking regimens. The results of the chemical analysis and standard toxicological assays showed a good inter-laboratory reproducibility for 1R6F as a reference cigarette, while there were some slight reproducible differences between 1R6F and 3R4F. In addition, we investigated the interchangeability of 1R6F with 3R4F in some additional toxicological assays that detect oxidative stress because oxidative stress is a principle endpoint used in tobacco research with next generation tobacco and nicotine delivery products (NGPs). Both 1R6F and 3R4F elicited comparable responses in the oxidative stress assays. Overall, our results showed inter-laboratory reproducibility in chemical and standard toxicological assessments of 1R6F; thus, suggesting the suitability of 1R6F as a reference cigarette. In addition, the results obtained in the oxidative stress assays provide insight into the interchangeability of 1R6F with 3R4F when used as a comparator for NGPs.</p></abstract>ARTICLE2020-12-31T00:00:00.000+00:00Numerical Simulation of the Burning Process in a King-Size Cigarette Based on Experimentally Derived Reaction Kineticshttps://sciendo.com/article/10.2478/cttr-2020-0014<abstract><title style='display:none'>Summary</title><p>A comprehensive two-dimensional (2D) mathematical model has been proposed to simulate the burning process of a king-size cigarette. The characteristics of this model are including: 1) the use of kinetic models for the evaporation of water, the pyrolysis of tobacco and the oxidation of char, 2) the application of mathematical relationships between the release amounts of certain products (i.e., “tar” and CO) and different reaction variables (i.e., temperatures and oxygen concentrations), 3) the introduction of mass, heat and momentum transports, 4) the consideration of filtration effects of the cigarette filter on “tar”. These characteristics were expressed in a set of coupled equations that can be solved numerically by FLUENT. The information about the char density field, temperature field, flow velocity field, “tar” and CO density fields and the filtration efficiency could be obtained from the model. This model was validated by comparing the predictions with experimental data on puff number, the temperatures at specific locations, the filtration efficiency and the yields of “tar” and CO under different puff intensities. The calculated results show a good agreement with the experimental data. The predicted puff number was 7.3, and the experimental puff number was 6.8. The standard root mean square error (NRMSE) between the experimental and the predicted temperatures at specific locations is &lt; 18%. The predicted filtration efficiency for “tar” was 46.1%, and the experimentally determined filtration efficiency for nicotine was 44.5%. The maximum relative deviations of the yields of “tar” and CO under different puff intensities were 8.9% and 10.6%, respectively.</p></abstract>ARTICLE2020-12-31T00:00:00.000+00:00Simulation of Heat and Mass Transfer of Cut Tobacco in a Batch Rotary Dryer by Multi-Objective Optimizationhttps://sciendo.com/article/10.2478/cttr-2020-0013<abstract><title style='display:none'>Summary</title><p>To simulate the drying process of cut tobacco in a batch rotary dryer, six different models of equilibrium moisture content were selected to calculate the driving force of mass transfer, and a mathematical model of heat and mass transfer was numerically solved. The multi-objective nonlinear problem of heat and mass transfer coefficients was optimized by employing a weight factor. The simulation results showed that the weight factor r was an important parameter for fitting results of moisture content and temperature. The model evaluation indices almost reached their minimal values with r at 0.1. For all the six equilibrium/classic models the fit was better for moisture content than for temperature. One model (M-H<sc>en</sc>/C) was superior to other equilibrium/classic models and the REA (reaction engineering approach) model. This study aims for an understanding of heat and mass transfer in the tobacco drying process, and provides a theoretical framework to support the prediction of temperature and moisture in various drying situations.</p></abstract>ARTICLE2020-12-31T00:00:00.000+00:00Variations of TSNA Levels in Tobaccos Upon Heating at Moderate Temperatureshttps://sciendo.com/article/10.2478/cttr-2020-0009<p>Tobacco-specific nitrosamines (TSNAs) including nitrosoanabasine (NAB), nitrosoanatabine (NAT), 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK), and nitrosonornicotine (NNN) are naturally present at trace levels in tobacco. During tobacco processing, preparation of expanded tobacco, and when tobacco is used in heat-not-burn type cigarettes, the tobacco is exposed to different degrees of heat. Heating of tobacco has been reported in the literature to increase the level of TSNAs. Since the increase of TSNAs in heated tobacco is still not well understood, the present study evaluated TSNA levels in six types of tobacco as a function of moderate heat exposure. These tobaccos included: flue-cured lower stalk, flue-cured upper stalk (US), Burley lower stalk, Burley upper stalk (US), and two Oriental blends (Turkey, Greece, Bulgaria, Northern Republic Macedonia). Heating was performed in sealed glass tubes at oven temperatures of 100 °C, 150 °C, 200 °C, and 250 °C for time intervals of 2 min and 5 min. The temperatures inside the glass tubes were lower than the targets and were monitored separately as a function of glass tube heating. The study showed no meaningful differences within tobacco type (by stalk position) but showed considerable differences in the levels of TSNAs between different tobaccos, with the Burley tobaccos having the highest levels, and the Orientals the lowest. For all tobacco types, TSNAs increase to some extent when temperature increases. For 2-min heating, the increase in TSNAs is relatively small up to about 200 °C, but the levels almost double when the oven temperature increases to 250 °C. For 5-min heating, the increase in TSNAs starts at about 150 °C with a maximum at 200 °C which can reach more than double the initial TSNA level. Longer heating at 250 °C (5 min) starts to cause TSNAs decomposition and the levels are reduced.</p>ARTICLE2020-09-25T00:00:00.000+00:00Robustness of HPHC Reduction for THS 2.2 Aerosol Compared with 3R4F Reference Cigarette Smoke Under High Intensity Puffing Conditionshttps://sciendo.com/article/10.2478/cttr-2020-0008<p>In the absence of standards specific for testing the reduction robustness of the levels of harmful and potentially harmful constituents (HPHCs), the aerosol from the THS 2.2, a heated tobacco product, was compared with the mainstream smoke of the 3R4F reference cigarette over a broad range of machine-smoking regimes. The average reduction and the introduced concept of threshold limits of robust reduction were derived from HPHC concentrations, in mass per tobacco-stick normalized per total puff volume, to propose an alternative for the assessment of products where nicotine-adjusted yields would be inappropriate. In addition, this study explores the influence of 3R4F reference cigarette filter ventilation, and discusses the roles of temperature and precursors in the present context of robustness of HPHC reduction. Fifty-four HPHCs were analyzed under multiple regimes in THS 2.2 aerosol and 3R4F cigarette smoke. The average reduction of HPHC concentrations compared across all regimes characterized the robustness. Threshold limits of reduction of individual HPHCs were statistically determined across all regimes. The results observed under Health Canada Intense (HCI) and more intense regimes indicated that on average the reductions in HPHCs levels investigated in THS 2.2 aerosol were more than 90% and that the majority of the 54 HPHCs investigated in THS 2.2 aerosol showed more than 90% reduction. The robustness of THS 2.2 in maintaining the levels of reduction of representative HPHCs, whatever the puffing regime, can be quantified. The mass of HPHC per tobacco-stick normalized per total puff volume is a valuable approach to compare the robustness of the performance of a product over a large range of puffing conditions. Our findings will greatly complement the assessment for robustness of current and future similar products where classical approaches would present limitations.</p>ARTICLE2020-09-25T00:00:00.000+00:00Extraction from Moist Snuff with Artificial Saliva of Benzo[]pyrene and Other Polycyclic Aromatic Hydrocarbonshttps://sciendo.com/article/10.2478/cttr-2019-0002<p>The present study evaluated <italic>in vitro</italic> extractability of various polycyclic aromatic hydrocarbons (PAHs) from moist snuff, when the extracting agent was water or artificial saliva. The extraction was performed on nine brands of moist snuff samples that are commercially available and were purchased from the market in January 2018. The moist snuff brands were selected to represent brands with different tobacco cut size descriptors and flavors. For the measurement of PAHs, two different analytical methods were used, an HPLC (High Performance Liquid Chromatography) method for measuring only benzo[<italic>a</italic>]pyrene (BaP) and a GC/MS/MS (Gas Chromatography Tandem Mass Spectrometry) method for measuring 21 PAHs (including BaP). These methods were modifications of preexistent methods reported in the literature. The results for BaP indicated that by extracting 500 mg of freeze-dried moist snuff with 6 portions of 20 mL water (120 mL), or with 4 portions of 20 mL artificial saliva, followed by two portions of 20 mL water, the BaP remains close to 100% in the solid material and it is not detected in the extracting solution. PAHs with a molecular weight similar or heavier than BaP also showed no extractability. Lighter PAHs such as fluorene, phenanthrene, anthracene, and 5-methylanthracene showed a relatively good extractability. An intermediate group including fluoranthene, pyrene, and benz[<italic>a</italic>]anthracene showed some extractability in the conditions of this <italic>in vitro</italic> experiment. This study is not a substitute for clinical studies regarding PAH uptake in human users of moist snuff. However, the results indicate very limited bioavailability of BaP and heavier PAHs from moist snuff. Higher, but variable bioavailability was indicated for lighter PAHs. Important implications of these findings are that: 1) measurably different BaP content of two moist snuff products is unlikely to result in any meaningfully different consumer exposure to BaP; and 2) biomarkers for one PAH cannot necessarily be used as a reliable indicator of exposure to another PAH, particularly if the molecular weights of the precursor PAHs differ since their bioavailabilities can be very different. [Beitr. Tabakforsch. Int. 28 (2019) 214–223]</p>ARTICLE2019-06-13T00:00:00.000+00:00en-us-1