rss_2.0Contributions to Tobacco & Nicotine Research FeedSciendo RSS Feed for Contributions to Tobacco & Nicotine Research to Tobacco & Nicotine Research Feed Review on Nicotine’s Role in Human Health<abstract> <title style='display:none'>Summary</title> <sec><title style='display:none'>Background</title> <p>Next generation of nicotine/tobacco products (NGPs) include electronic cigarettes (ECs), heated tobacco products (HTPs), oral nicotine pouches (NPs) and smokeless tobacco (SLT) products (in particular snus). These products commonly contain nicotine and are intended to replace combustible cigarettes (CCs) and thus can be regarded as tobacco harm reduction products. To fulfill this role, it is essential that nicotine, which has well established addictive properties, is not causally related to health risks upon chronic use.</p> </sec> <sec><title style='display:none'>Objectives</title> <p>The purpose of this review is to evaluate the scientific literature to answer the question, whether nicotine is involved in the development of any diseases or disorders associated with the acute, short, mid- and long-term use of NGPs. Appropriate results from studies with nicotine replacement therapy (NRT) products (gum, patches, inhalers, lozenges) are included as reference basis for inferring the health effects of NGPs. Furthermore, suggestions for filling identified gaps and for avoiding or minimizing limitations and weaknesses in study design are provided.</p> </sec> <sec><title style='display:none'>Methods</title> <p>Literature databases such as MEDLINE, Google Scholar and an in-house ABF library (containing about 180,000 articles) were searched for relevant articles. Furthermore, pertinent monographs (such as the US Surgeon General Reports) and recent reviews were screened for further publications. Inclusion criteria were: all human studies investigating the association between use (preferably chronic use) of the nicotine/tobacco products mentioned above and health effects, including diseases, disorders, changes in biomarkers of biological effect (BOBEs). <italic>In vivo</italic> (animal) and <italic>in vitro</italic> studies were also considered, provided effects of NGPs in the presence and absence of nicotine or in relation to the nicotine exposure dose were reported. Also, reference lists of recent suitable articles were screened. In total, about 500 articles were retrieved by this approach. The role of nicotine was evaluated by considering the article authors’ statements and their cited references as well as by own judgement of reported results. Human studies are presented in a standardized table format.</p> </sec> <sec><title style='display:none'>Results</title> <p>In total, 183 human studies were evaluated, with cardiovascular diseases (CVD) ranking highest (N = 75 studies), followed by respiratory diseases (43), oral health disorders (23), cancer (10), metabolic syndrome (7), reproduction disorders (5) and several other diseases (&lt; 5). The majority of studies do not provide evidence for a participation of nicotine in the pathogenesis. Some (weak) evidence was found that nicotine might be involved in some CVD-related effects and metabolic syndrome. This would be also supported by results from animal and <italic>in vitro</italic> studies.</p> </sec> <sec><title style='display:none'>Discussion</title> <p>Human studies showed some severe limitations and weaknesses with respect to the study design and time of availability of NGPs on the market. A severe flaw is the insufficient consideration of dual use (NGP + CC), particularly in studies on chronic use, which could have led to erroneously increased risks for NGPs with direct consequences also for the role of nicotine. Additionally, prior effects from using CC have an impact. Both circumstances could have led to inaccurate conclusions in terms of elevated risk levels, which require changes in method designs. Suggestions for methodological improvements are provided for future studies.</p> </sec> <sec><title style='display:none'>Conclusions</title> <p>A final evaluation of the role of nicotine in disease development in NGP users is currently not possible because use durations are too short. Chronic studies often suffer from insufficient separation between NGP only and dual use together with CCs, which may falsely increase the observed health risk. There is some limited evidence that nicotine may be involved in CVD-related effects, which, however, has to be verified in well controlled long-term studies. The potential involvement of nicotine in other patho-mechanisms also requires further research.</p> </sec> </abstract>ARTICLEtrue Comparative Toxicological Screening of a Closed-End Heated Tobacco Product *<abstract> <title style='display:none'>SUMMARY</title> <p>Heated tobacco products (HTPs) are a recent category of tobacco products, with their relative safety compared to cigarette smoking and potential to help smokers to quit being two reasons why regulators may consider their market approval. Designed to heat tobacco rather than to burn in order to produce aerosol, different heating techniques are applied to commercial HTPs, which may result in differing aerosol formation. Therefore, each product requires separate assessment. This work focuses on a closed-end HTP (coded as HTP-A), which is electrically heated and designed to allow puffing air flow to bypass its tobacco section, resulting in reduced oxygen concentration within the tobacco section during heating and aerosol forming. To provide a preliminary aerosol chemistry and <italic>in vitro</italic> toxicological screening, this study assessed HTP-A against a commercial electrically heated HTP (IQOS<sup>TM</sup>, coded as HTP-B) and a 3R4F reference cigarette. Under Health Canada Intense (HCI) smoking regime, the levels of 9 regulatory priority toxicants in the aerosol of HTP-A were either reduced or comparable to those in HTP-B on a per-stick basis. Additionally, both HTPs showed significant reduction (greater than 90%) in comparison to those measured in mainstream smoke of 3R4F cigarette for these toxicants. Using a set of standard <italic>in vitro</italic> toxicological assays (Ames, Micronucleus and Neutral Red Uptake), the two HTPs showed no observable responses while significant toxicity responses were recorded for 3R4F’s total particulate matter. Based on these preliminary results, the novel closed-end HTP-A design may provide similar toxicological profiles to the comparator HTP-B. Further toxicological and clinical assessments are warranted to evaluate HTP-A’s potential for exposure or disease risk reduction. [Contrib. Tob. Nicotine Res. 32 (2023) 146–156]</p> </abstract>ARTICLEtrue J. Michael Moore, Recipient of the 2023 Tobacco Science Research Conference Lifetime Achievement Award Pumping Method for Assessing Airtightness of Packs - Application to Heated Tobacco Products *<abstract> <title style='display:none'>SUMMARY</title> <p>The airtightness of heated tobacco product (HTP) packs is a very important indicator for the product quality and is also of great importance during the conditioning process. A method for evaluation of the airtightness was developed based on the air pressure difference in a constant pumping configuration. The essential feature of this method is that the pressure difference between the inside and the outside of the HTP packs during the deflation process is used to characterize the sealing quality of HTP packs. The detailed setup, the principle as well as the determination procedure are described. The accuracy and the repeatability of the method were assessed, and the effect of airtightness on the conditioning process was also investigated. The developed method is proven to be reliable with a standard deviation less than 0.09 kPa and repeatability less than 0.30 kPa. In addition, it was found that, although the transmission of moisture between HTPs and atmosphere could not be entirely prevented by the packs, airtightness still plays a significant role during the conditioning process, especially if the airtightness was at a relatively low level (e.g., lower than 1.5 kPa under a pumping flow rate of 200 mL/min). The method provides a promising way to assess and monitor the sealing quality of HTP packs, and it is suggested that the airtightness of the pack should not be lower than 2 kPa under a pumping flow rate of 200 mL/min. [Contrib. Tob. Nicotine Res. 32 (2023) 140–145]</p> </abstract>ARTICLEtrue’ Note Nicotine Pharmacokinetics of Oral Nicotine Pouches Across Varying Flavours and Nicotine Content *<abstract> <title style='display:none'>SUMMARY</title> <sec> <title style='display:none'>Background</title> <p>In recent years several nicotine products have been introduced that aim to offer smokers an alternative to cigarettes. As well as having fewer toxicants than combustible cigarettes, such nicotine products must be able to deliver nicotine efficiently. The aim of this study was to determine and compare the pharmacokinetics of nicotine absorption from nine oral tobacco-free smokeless nicotine pouches with varying nicotine content and flavours.</p> </sec> <sec> <title style='display:none'>Methods</title> <p>In a randomised, open-labelled, controlled, crossover clinical study, nicotine pharmacokinetics and product-liking were compared between nine nicotine pouches (<italic>Velo</italic>, BAT; 4- or 7-mg nicotine per pouch and in eight flavours). During a 10-day confinement period, 42 healthy adult participants, who were current smokers of combustible cigarettes, used a single study product once each day during a 45-min use period following overnight nicotine abstinence.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Maximum plasma nicotine concentration and area under curve for nicotine concentration <italic>versus</italic> time 180 min after the start of study product use were significantly greater for the 7-mg than for the 4-mg <italic>Velo</italic> pouches <italic>(p</italic> &lt; 0.0001). These values did not differ between flavours among the 7-mg <italic>Velo</italic> nicotine pouches after adjustment for multiple comparisons (both <italic>p</italic> &gt; 0.003). The median time to maximum plasma nicotine concentrations and mean product-liking scores were similar regardless of nicotine content and flavour.</p> </sec> <sec> <title style='display:none'>Conclusions</title> <p>Regardless of flavour, nicotine pouches with the same nicotine content and formulation produce similar pharmacokinetic parameters and can deliver nicotine efficiently. Nicotine pouches could be a satisfying alternative for smokers switching from conventional cigarettes. [Contrib. Tob. Nicotine Res. 32 (2023) 130–139]</p> </sec> </abstract>ARTICLEtrue Testing of Tobacco and Smoke to Examine Cigarette Temporal Variability<abstract> <title style='display:none'>Summary</title> <p>Commercial cigarettes were analyzed for harmful and potentially harmful constituents (HPHCs) in tobacco and smoke to investigate temporal product variability independent of analytical variability over one week, one year, and three years. Cigarettes from the worldwide market with various design features were collected over a 3-year period, stored, and tested concurrently for HPHCs to minimize analytical variability; repeat testing of reference cigarette 3R4F was included as an analytical control for the study design. Physical parameters were found to be relatively consistent. No trends in variability were noted based on blend type, smoke analyte matrix, or magnitude of an HPHC's yield. Combustion-related HPHCs generally showed low variation. Long-term batch-to-batch variability was found to be higher than short-term variability for tobacco-related compounds that have the potential to vary over time due to weather and agronomic practices. “Tar”, nicotine, and carbon monoxide were tested in multiple labs and showed greater lab-to-lab variability than batch-to-batch variability across all phases. Based on the results of this study, commercial cigarette products appear to have relatively low product variability. The low analyte variability noted in this study with products tested under unconventionally controlled analytical conditions serves to indicate that analytical variability may be a significant contributor to overall variability for general product testing over time and in interlaboratory studies. Laboratory controls and using a matched reference product across studies and between laboratories are important to assess testing differences and variability.</p> </abstract>ARTICLEtrue Cross-Sectional Survey on Prevalence and Behaviour of Smokeless Tobacco Use Among Tobacco Users in China<abstract> <title style='display:none'>Summary</title> <p>Increasing tobacco control and public health awareness have increased smokers’ attempts to quit smoking. However, some smokers also seek alternative products claimed to pose less risks. The use of smokeless tobacco (ST) products may thus increase in some countries which are not traditionally ST markets. To provide a cross-sectional picture on ST usage in China, a survey was conducted from December 2019 to March 2020 in representative metropolitan cities (divided into three tiers by their populations and gross domestic product (GDP) sizes), from which 3,000 tobacco users and 801 ST users were randomly recruited to provide a snapshot of ST usage behaviour and other pertinent factors for Chinese tobacco users. The study included questionnaires designed to probe potential reasons behind ST use, usage habits, and nicotine dependence attributes. These questions were devised to cover the type of tobacco products used, users’ age, gender, city of residence, residence time, household monthly income, etc., and was supported by some verification questions. Mann-Whitney-analysis was used for significance analysis between different groups. The results showed that ST prevalence for Chinese tobacco users was around 2.1%. The proportion of exclusively ST use was about 8.99%, and the mean conversion time to habitual ST use was about three months. Demographic information such as the city tiers where ST users lived, their age, gender, educational and income levels appeared to correlate with ST use habits although more studies are needed to verify the observations. The fact that a small but measurable population of Chinese ST users exists has important implications for tobacco control. This study provides the first large-scale, single-time-point survey on Chinese ST user profiles, which may help the future research on tobacco control policy regarding ST products in China.</p> </abstract>ARTICLEtrue of Varying Tobacco Rod Circumference on Cigarette's Dynamic Ventilation Rate and Combustion State During Machine Smoking<abstract> <title style='display:none'>Summary</title> <p>Cigarette ventilation characteristics are one of the important design factors that affect the combustion state and therefore smoke release. In order to study the changes of ventilation characteristics and the combustion state of cigarettes with different rod circumferences during smoking, a device was designed that could flexibly measure the different ventilation characteristics along the cigarette rod. The device was utilized to measure the changes of the total ventilation rate and filter ventilation rate of cigarettes with different rod circumference in both burned and unburned conditions. At the same time, a test method was implemented to measure the temperature of the combustion coal puff-by-puff during the smoking process. The relationship between ventilation and the combustion state was analyzed on a per-puff basis. The results show that with the decrease of the rod circumference from 24 mm to 20 mm and 17 mm, the total ventilation rate under burning conditions changed considerably compared with unburned conditions, increasing by 55.7%, 60.5% and 74.5% on average, respectively. The ventilation of the cigarette paper played a major role in regulating the ventilation during puffing. With the increase from 17 mm to 24 mm in circumference, the combustion efficiency of the tobacco decreased as indicated by a range of thermophysical parameters of the burning coal.</p> </abstract>ARTICLEtrue of the Particle Size Distribution and Vapor Phase of Electronic Nicotine Delivery Systems Using Two Impactors<abstract> <title style='display:none'>Summary</title> <p>Electronic Nicotine Delivery Systems (ENDS) contain numerous volatile aerosol constituents (e.g., nicotine, propylene glycol, flavors, etc.). Past work clearly indicates the temporal and chemical dynamics of ENDS aerosol requires consideration of these volatile constituents when measuring the particle size distribution. An MSP-135-8 Mini MOUDI™ and Electrical Low Pressure Impactor (ELPI<sup>®</sup>+) were used to measure the particle size distribution of two JUUL ENDS products. Volatile chemicals were measured from each cascade impactor's exhaust airflow to assess their effect on collection efficiency. Similar mass median aerodynamic diameters were obtained for both ENDS products by both cascade impactors, however the geometric standard deviation from the ELPI<sup>®</sup>+ measurements were larger for both products than measurements using the Mini MOUDI™ impactor. Although the measured mass of volatile chemicals was greater in the exhaust from the Mini MOUDI™ impactor, a greater variety of volatile chemicals were found within the exhaust of the ELPI<sup>®</sup>+. The greater variety of volatile chemicals correlated with more room air sampling by the ELPI<sup>®</sup>+. The reduced amount of volatile chemicals measured in the exhaust of the ELPI<sup>®</sup>+ may be due to their collection by the vacuum oil used in the sintered collection plates of the ELPI<sup>®</sup>+. Accounting for the measured volatile chemicals improved the recovery efficiency of the Mini MOUDI™ impactor by 2.9–7.5% with the average recovery efficiency exceeding 82% for the two JUUL ENDS Products. In comparison, accounting for the measured volatile constituents increased the recovery efficiency of the ELPI<sup>®</sup>+ impactor by 0.4% or less, which did not narrow the recovery efficiency range, that based upon the estimated dilution, consistently exceeded the measured mass loss from both JUUL ENDS products.</p> </abstract>ARTICLEtrue Inter-Laboratory Comparison for the Urinary Acrolein Biomarker 3-Hydroxypropyl-Mercapturic Acid (3-HPMA)<abstract> <title style='display:none'>Summary</title> <p>An inter-laboratory comparison study on the acrolein biomarker of exposure 3-hydroxypropyl-mercapturic acid (3-HPMA) with 12 laboratories from 7 globally distributed countries was performed. The laboratories received coded triplicates of 4 spiked and lyophilized urine samples (LU, 12 samples) as well as 5 authentic urine pool samples (PU, 15 samples) covering the 3-HPMA concentration range from background (non-smoking) to heavy smoking levels for analysis by using their own (in-house) analytical method. All laboratories applied liquid chromatography with tandem mass spectrometry (LC-MS/MS), with most of them (10 of 12) using solid phase extraction (SPE) as sample work-up procedure. The intra-laboratory variation (indicating repeatability) was determined by calculating the standard deviation (s<sub>r</sub>) and the coefficient of variation (CV<sub>r</sub>) of the triplicates, whereas the inter-laboratory variation (indicating reproducibility) was determined by calculating the standard deviation between laboratories (s<sub>R</sub>) and the corresponding coefficient of variation (CV<sub>R</sub>). After removal of outlier samples or laboratories, the mean CV<sub>r</sub> values for LU and PU test samples ranged from 2.1–3.6% (mean: 2.8%) and 2.4–3.7% (mean: 3.3%), respectively, indicating good repeatability for the determination of 3-HPMA in both sample types. CV<sub>R</sub> for LU and PU test samples ranged from 9.1–31.9% (mean: 18.8%) and 13.9–27.0% (mean: 18.5%), respectively, indicating limited reproducibility in 3-HPMA analysis for both sample types. Re-calculation of the PU results by applying an embedded calibration (EC), derived from the reported peak areas for the LU test samples, somewhat improved the CV<sub>R</sub> values (range: 9.6–28.8%, mean: 16.7%).</p> <p>It is concluded that the intra-laboratory variation (repeatability) in the determination of 3-HPMA in urine is in general acceptable in the participating laboratories, while the inter-laboratory variability requires further improvement. The relatively small reduction in the inter-laboratory variability (s<sub>R</sub> and CV<sub>R</sub>) by applying an EC suggests that other methodological factors than the standard reference material for 3-HPMA have to be addressed to achieve further improvement in reproducibility.</p> </abstract>ARTICLEtrue Intent and Product Appeal of Velo Nicotine Pouches Among Current Tobacco Users and Nonusers of Tobacco<abstract> <title style='display:none'>Summary</title> <sec><title style='display:none'>Background and objectives</title> <p>Oral nicotine pouches is a rapidly growing product category that potentially offers less risk than combustible tobacco products. Nicotine pouches may provide harm reduction for smokers because they contain no tobacco and have reduced harmful constituents compared to traditional tobacco product categories. Any potential public health benefit must weigh the likelihood that current tobacco users will switch to the lower-risk product against the likelihood that nonusers will start using tobacco products. To our knowledge, no existing studies provide population-level estimates of purchase intent or product appeal across tobacco user groups or how product characteristics might affect those variables.</p> </sec> <sec><title style='display:none'>Methods</title> <p>This paper presents population-level estimates of purchase intent and product appeal for multiple Velo nicotine pouch products (including different flavors, nicotine strengths, format, and packaging) among five adult tobacco user groups (current established cigarette smokers, current established non-cigarette tobacco users, current tobacco experimenters, former tobacco users, and never ever tobacco users). Over 49,000 respondents were surveyed across twelve analytic samples.</p> </sec> <sec><title style='display:none'>Results</title> <p>Results for the pooled sample as well as for each individual sample were remarkably consistent for every product. Ratings of purchase intent and appeal are higher for current tobacco users (current established cigarette smokers, current established non-cigarette tobacco users, and current tobacco experimenters) than for former and never ever tobacco users.</p> </sec> <sec><title style='display:none'>Conclusions and scientific significance</title> <p>Variation in product characteristics had little or no effect on purchase intent or appeal ratings across tobacco user groups, suggesting that product characteristics do not materially affect public health.</p> </sec> </abstract>ARTICLEtrue and Quantitative Analyses of the Enantiomers of Nicotine and Related Alkaloids Employing Chiral Supercritical Fluid Chromatography in Commercial Nicotine Samples and in E-Cigarette Products<abstract> <title style='display:none'>Summary</title> <p>Several commercial sources of tobacco-derived nicotine (TDN) and synthetic nicotine (SyN) and a variety of e-cigarette liquids employing either TDN or SyN have been evaluated to determine the enantiomer distributions of R- and S-nicotine and R- and S-nornicotine by chiral supercritical fluid chromatography (chiral-SFC) with UV diode array detection (DAD-UV). The data generated are used to test the mismatched <italic>vs</italic>. matched hypothesis of C<sc>heetham</sc> <italic>et al.</italic> as a means to distinguish products containing TDN from products with SyN.</p> <p>Two sets of experiments were conducted in this study. The first experiment was conducted on a series of 11 commercial nicotine samples (three characterized as tobacco-derived and eight characterized as synthetic nicotine). The commercial nicotine samples were either from a tobacco-derived nicotine (TDN) source or were synthetic nicotine (SyN). Some of the commercial nicotine samples were nicotine salts. The second experiment was conducted on e-liquids from a set of 11 e-cigarettes. The nicotine in the e-liquids was either from TDN or SyN. The e-liquid samples were differentiated based on the advertised information on the internet or from printed information on the e-cigarette packaging.</p> <p>None of the three commercial TDN samples in the first experiment could be unequivocally characterized as coming from a tobacco source. Five of the eight commercial SyN samples were correctly characterized as SyN based on the matched <italic>vs</italic>. mismatched nicotine and nornicotine hypothesis of C<sc>heetham</sc> <italic>et al.</italic></p> <p>In the second experiment, none of the e-liquids characterized as being from TDN sources could be unequivocally characterized as coming from a tobacco source. All of the e-liquids characterized as being from SyN sources were either characterized as equivocal or of uncertain origin based on the matched <italic>vs</italic>. mismatched nicotine and nornicotine hypothesis of C<sc>heetham</sc> <italic>et al.</italic></p> <p>These sets of experiments represent an excellent example of the difficulty that the United States Food and Drug Administration is having in trying to determine if TDN or SyN is being used in tobacco products. Even highly advanced chromatographic methods such as chiral-SFC were not able to unequivocally distinguish products with TDN from products with SyN 100% of the time.</p> <p>Other analytical methods such as <sup>14</sup>C quantitation of nicotine samples by accelerator mass spectrometry offer a more reliable determinate of nicotine source (TDN <italic>vs</italic>. SyN) and can be used to identify misbranded products labelled as containing SyN, even though this methodology is more expensive and offered in limited locations.</p> </abstract>ARTICLEtrue’ Note Intent and Appeal of ENDS Products among Current, Former and Never Ever Users of Tobacco Products in the U.S.<abstract> <title style='display:none'>SUMMARY</title> <sec> <title style='display:none'>Background and objectives</title> <p>The last decade has seen extensive research into electronic nicotine delivery systems (ENDS) such as e-cigarettes. Although some studies assess ENDS’ potential benefits, there is a paucity of studies that provide population-level estimates of purchase intent or product appeal among various tobacco user groups, or that have examined the impact of different product characteristics on those variables.</p> </sec> <sec> <title style='display:none'>Methods</title> <p>Purchase intent and product appeal ratings were analyzed from six online studies for multiple sub-brands of Vuse vapor products (including different flavors, nicotine levels, and device styles). The sample in each study was weighted to represent the adult U.S. population of current established, former established, and never established cigarette smokers on five key demographics; providing population-level estimates.</p> </sec> <sec> <title style='display:none'>Results</title> <p>Results for purchase intent and appeal are remarkably consistent. Ratings of purchase intent and appeal are higher for current tobacco users (current established cigarette smokers, current established non-cigarette tobacco users, and current tobacco experimenters) than for former and never ever tobacco users.</p> </sec> <sec> <title style='display:none'>Conclusions and scientific significance</title> <p>These findings show that varying sub-brands of an e-cigarette has little or no impact on population level purchase intent and appeal ratings across tobacco user groups. Additionally, greater variability in ratings among current tobacco experimenters than other tobacco user groups is discussed as well as correlations between measures. This paper provides the first population estimates of both purchase intent and product appeal for various ENDS products among adult tobacco users and nonusers; information that is critical for evaluating the impact on public health. [Contrib. Tob. Nicotine Res. 32 (2023) 34–42]</p> </sec> </abstract>ARTICLEtrue do Risk Perceptions Drive Smokers to Completely Switch to a Smoke-Free Tobacco Product ()? A Four-Country Cohort Study<abstract> <title style='display:none'>SUMMARY</title> <sec> <title style='display:none'>Background</title> <p>The perceived reduced formation of harmful chemicals (RF) or perceived reduced risk of harm (RH) of a smoke-free tobacco product relative to combustible tobacco products may influence its acceptance and use patterns among adult smokers and therefore impact public health. We analyzed whether and how the RF and/or RH of the heated tobacco product (HTP) <italic>IQOS</italic><sup>™</sup> impacted “exclusive” (100%) <italic>IQOS</italic><sup>™</sup> use in Japan, Italy, Germany, and Russia.</p> </sec> <sec> <title style='display:none'>Methods</title> <p>Between 2016 and 2020, adult participants from longitudinal <italic>IQOS</italic><sup>™</sup> user cohorts in Japan (<italic>N</italic> = 6257), Italy (<italic>N</italic> = 8137), Germany (<italic>N</italic> = 8474), and Russia (<italic>N</italic> = 7231) repeatedly indicated the reasons for using <italic>IQOS</italic><sup>™</sup>, including reasons referring to RF and RH, during their first 48 weeks in the cohort. Logistic and Cox regression were used to analyze the relationships between RF and/or RH indications for using <italic>IQOS</italic><sup>™</sup> and exclusive or stable exclusive <italic>IQOS</italic><sup>™</sup> use.</p> </sec> <sec> <title style='display:none'>Results</title> <p>At week 48, exclusive <italic>IQOS</italic><sup>™</sup> use in Japan (odds ratio [OR] = 1.89), Italy (OR = 3.35), Germany (OR = 3.48), and Russia (OR = 3.05) was more likely among participants who more frequently (highest <italic>vs</italic>. lowest category of number of RF and/or RH indications) indicated RF and/or RH as a reason for using <italic>IQOS</italic><sup>™</sup>. In Japan, where other HTPs were also marketed, this was also true for the overall HTP category. Also, in Japan where RF and RH could be indicated separately as reasons for using <italic>IQOS</italic><sup>™</sup>, indicating RH (OR = 2.92) compared to RF (OR = 1.81) resulted in a greater likelihood of exclusive <italic>IQOS</italic><sup>™</sup> use within the highest category of RF or RH indications. In Japan (hazard ratio [HR] = 0.74), Italy (HR = 0.80), Germany (HR = 0.72), and Russia (HR = 0.85), <italic>IQOS</italic><sup>™</sup> users who indicated RF and/or RH as a reason for using <italic>IQOS</italic><sup>™</sup> had a lower risk of becoming a stable nonexclusive than stable exclusive <italic>IQOS</italic><sup>™</sup> user as well as a 10–25% lower number of weeks until reaching stable exclusive <italic>IQOS</italic><sup>™</sup> use.</p> </sec> <sec> <title style='display:none'>Conclusions</title> <p>Perceived reduced formation of harmful chemicals (RF) or perceived reduced risk of harm (RH) of <italic>IQOS</italic><sup>™</sup> have a significant impact on <italic>IQOS</italic><sup>™</sup> users’ switching to exclusive <italic>IQOS</italic><sup>™</sup> use and the acceleration of stable exclusive <italic>IQOS</italic><sup>™</sup> use. This may also be true for the overall HTP category. Moreover, perceived RH of <italic>IQOS</italic><sup>™</sup> seems to be a stronger driver for exclusive <italic>IQOS</italic><sup>™</sup> use than perceived RF. [Contrib. Tob. Nicotine Res. 32 (2023) 50–64]</p> </sec> </abstract>ARTICLEtrue and Quantitation of Nicotine Polacrilex in Nicotine Pouches and Other Oral Nicotine Delivery Products<abstract> <title style='display:none'>SUMMARY</title> <p>Nicotine polacrilex (CAS-No. 96055-45-7) can be used as the source of nicotine in nicotine pouches and other oral nicotine delivery products such as lozenges, tablets, and gums. The compound is the salt of nicotine with Amberlite IRP64, a copolymer of methacrylic acid and divinylbenzene. Present study describes a unique procedure to identify the presence of the compound nicotine polacrilex in oral nicotine delivery products and to evaluate its level. In oral nicotine delivery products, nicotine polacrilex is used in a mixture with other ingredients such as microcrystalline cellulose (MCC), maltitol, sweeteners, flavors, salts (such as Na<sub>2</sub>CO<sub>3</sub>, NaHCO<sub>3</sub>), water, etc. These ingredients make the analysis of the compound nicotine polacrilex by spectroscopic techniques such as IR or Raman difficult. Also, since nicotine polacrilex is insoluble in common solvents, the analysis using solutions is not possible. The study is also attempting to detect if the product contains only nicotine polacrilex or if it has additional nicotine in a different form (e.g., nicotine or nicotine tartrate). The analysis uses pyrolysis-GC/MS (Py-GC/MS) and the detection and quantitation of nicotine polacrilex is based on measuring the pyrolysis products of divinylbenzene (DVB) moiety from the Amberlite IRP64. The detection was proven very reliable by this procedure, while the quantitation showed some variability caused by the typical variability in the pyrolysis process. [Contrib. Tob. Nicotine Res. 32 (2023) 43–49]</p> </abstract>ARTICLEtrue of Tobacco Alkaloids<abstract><title style='display:none'>Abstract</title><p> Chemical transformation: In air oxidation of nicotine at room temperature, N´-methylmyosmine, which is supposed to be an active intermediate of degradation, cotinine, nicotine-N´-oxide, nicotyrine, myosmine, 3-pyridylpropyI ketone, 3-pyridylmethyI ketone, nicotinic acid, methylamine and ammonia were isolated. N´-Methylmyosmine was first characterized by 1H-NMR. When N´-methylmyosmine was heated, N-methylnicotinamide and nicotyrine were obtained in addition to a large amount of polymerized resinous substances. 2´(S)-nicotine-1´-N-oxide was rearranged to acetyl pseudooxynicotine by reaction with acetyl chloride or acetyl anhydride. This rearrangement could be generally useful for the preparation of Δ1-pyrrolines or Δ1-piperideines. When appropriate acetyl groups were used, the products were effective in improving tobacco taste. </p><p>Phytochemical transformation: Transformation of alkaloids in the tobacco plant was investigated by measuring their optical rotatory power, from which it was presumed that nicotine is biosynthesized in the S-form. The nornicotine formed in the leaves is synthesized from S-nicotine, but the one formed in the root is synthesized in the racemic form, indicating a route different from that found in the leaves. Secondary amine alkaloids such as anabasine and anatabine are in the racemic form. From Cherry Red tobacco, a transformation product of nornicotine. 1-(1´-2´(S)-nornicotino)1-β-D-fructofuranoside (m.p. 66-68°C), was isolated for the first time. The structure was confirmed physico-chemically and finally by synthesis. This compound increased markedly during curing, especially at the drying stage, suggesting formation through a non-enzymatic process. </p><p>Microbial transformation: 2´(S)-nicotine-1´-N-oxide, which is the most common natural oxidation product of nicotine, was degraded by bacteria abundant on the tobacco leaf surface and in the tobacco field soil. The isolated micro-organisms belong to genus Arthrobacter. Degradation pathway was: nicotine-N´-oxide → N´-methylmyosmine (60 % - 70 % yield) → 4-oxo-4- (3´-pyridyl)butyric acid, whereas nicotine degraded slowly by a different route: S-nicotine → 6-hydroxy-nicotine → 6-hydroxy-N´-methylmyosmine. No analogous and homologous oxides tested were degraded by the bacteria. 1´(R)-2´(S)nicotine-1´-N-oxide was preferentially degraded, compared to 1 ´(S)2´(S)-nicotine-1´-N- oxide. </p></abstract>ARTICLEtrue Volatile Components of Burley Tobacco<abstract><title style='display:none'>Abstract</title><p> The constituents of the neutral volatiles in air-cured Burley tobacco were studied, and the following 19 substances were newly added to our lists: </p><p>1. 6-Methyl-6,9-oxidonon-4-en-2-ol </p><p>2. 5-Isopropylnon-3-en-2,8-dioI </p><p>3. 5-Isopropylnonan-2,8-diol </p><p>4. 3,3,5-Trimethyl-8-isopropyl-4,9-dioxabicyclo-[3.3.1]nonan-2-oI </p><p>5. 2-(1-Methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]-octan-6-yl)propan-2-ol </p><p>6. 3-Oxoactinidol </p><p>7. 5-Isopropyl-7-(2-methyltetrahydrofur-2-yl)hept-6-en-2-ol </p><p>8. O-Methyl acetophenone </p><p>9. 1,5,5-Trimethyl-9-oxabicyclo[4.3.0]nonan-3-one </p><p>10. 4-(3-Hydroxybutylidene)-3,5,5-trimethylcyclohex-2-en-1-one </p><p>11. (1-Methyl-4-isopropyl-7,8-dioxabicyclo[3.2.1]-octan-6-yl)methyl ketone </p><p>12. 6,10-Dimethyl-2-(1-methylethenyl)spiro[4.5]dec-6-en-8-one (solavetivone) </p><p>13. 5-Isopropyl-7-(2-methyltetrahydrofur-2-yl)hept-6-en-2-one </p><p>14. 4-Ethyl-4-methylbutan-4-olide </p><p>15. Phthalide </p><p>16. Hydroxydihydrobovolide </p><p>17. 1,2-Dimethoxy benzene </p><p>18. o-Anisidine </p><p>19. Methylanthranilate </p><p>A large number of identified compounds may be viewed as degradation products of carotenoids and thunberganoids. These compounds have a characteristic aroma and are thought to be key flavour components in the essential oils of tobacco. The presence of any labdanoid hydrocarbons or their oxygenated products was not recognized in our Burley tobacco extract. Burley tobacco is thought to be deficient in labdanoid compounds. </p></abstract>ARTICLEtrue Spectrophotometric Analysis of the Chemical Composition of Tobacco: Part 2: TotaI AIkaloids<abstract><title style='display:none'>Abstract</title><p> This paper illustrates the potential of a computerized spectrophotometer for measuring total alkaloids in tobacco. Prediction equations were developed for three optical parameters. Of the three parameters investigated d<sup>2</sup> (log (1/R)) /d/<sup>2</sup> gave the best results and d R / R d l gave better results than log (1/R), where reflectance R is the ratio of the detector signal of the sample to the detector signal of the ceramic standard in the reflectance mode. The coefficient of determination r<sup>2</sup> for the prediction equation containing d<sup>2</sup> (log (1/R)) /d/<sup>2</sup> terms at 10 different wavelengths was 0.975. This equation predicted the total alkaloids in an independent set of samples with a standard error of 0.438 %. Instrument noise contributed 43 % of the variation, the remainder was attributed to anomalies of the chemical methods.</p></abstract>ARTICLEtrue