Nicotine Content Research Articles

Sex differences in appeal, reward, and sensory experience of E-cigarette flavors among adults who smoke cigarettes

ObjectiveFlavors enhance nicotine e-cigarette appeal by altering sensory experience. Females may be more sensitive to tobacco-associated cues and uniquely affected by flavor. The current study is an exploratory analysis to examine differences by sex on reward, appeal, and sensory experience of popular e-cigarette flavors. MethodsAdults (N = 121) who use cigarettes (≥1 cigarette/day) were enrolled in a laboratory study in which they vaped four e-cigarette flavors (tobacco, cherry, menthol, vanilla; in separate lab sessions) in one of two freebase nicotine concentrations (6 mg/ml,18 mg/ml). Following exposures, participants rated e-cigarette reward using the Drug Effects Questionnaire (DEQ), flavor and overall e-cigarette appeal using Labeled Hedonic Scales (LHS), and intensity of flavor, irritation, coolness, fruitiness, and sweetness using Generalized Labeled Magnitude Scales (gLMS). Linear mixed models were conducted for outcomes to analyze effects of sex, flavor, and sex x flavor interaction. ResultsFor DEQ ratings, there was a trend (p = .08) toward a sex x flavor interaction, in which menthol flavor produced more reward than other flavors for females, but not males. For LHS ratings, there was a significant sex x flavor interaction (p = .03) for overall e-cigarette experience with females but not males rating menthol higher than other flavors. All gLMS scales but irritation showed that females generally had greater differences between flavors compared to males (ps ≤ 0.03). ConclusionMenthol in e-cigarettes may play an important role in mediating appeal and/or reward among females. This may be due in part to their ability to better detect sensory effects of e-cigarettes.

Harm perceptions across vaping product features: An on-line cross-sectional survey of adults who smoke and/or vape in the United Kingdom.

Vaping products are diverse with a wide variety of features, and popular products change rapidly. This study examined the features and types of vaping products that people who smoke and/or vape perceive contribute to the health harms of vaping. This was a cross-sectional survey co-designed with adults who smoked/vaped and pre-registered. An on-line survey (November 2022) was used of a convenience sample of adults in the United Kingdom who smoked and/or vaped (n = 494). As primary outcomes, respondents were asked to select any of 15 vaping product features they perceived might have any effect on the health harms of vaping (for each: selected, not selected). Independent variables were smoking/vaping status (smoke and vape; vape, formerly smoked; vape, never regularly smoked; smoke, do not currently vape); relative vaping harm perceptions [less harmful than smoking (accurate), equally/more harmful than smoking or do not know/refused (other)]. Binary logistic regressions were used to compare outcomes by current vaping/smoking status and relative harm perceptions, adjusting for age and sex. Most people (54.7%) selected between one and three features. The most frequently selected were nicotine concentration (62.2%) and amount of e-liquid consumed (59.1%), followed by nicotine type (e.g. salt or freebase; 33.0%), source/purchase location (25.3%), flavours (24.7%), temperature to heat e-liquid (21.1%), heat produced by device (20.9%), e-liquid brand (20.9%), amount of emissions (18.6%), device type (e.g. disposable, pod, tank; 17.2%), material of tank (17.0%), power/wattage (13.0%), device brand (8.1%), device size (4.1%) and device weight (2.4%). Higher nicotine concentrations, more e-liquid and salt (versus freebase) nicotine were perceived to confer greater harms. Disposables were perceived as slightly more harmful than reusable devices. There were few differences by current vaping/smoking status and between those with accurate (versus other) harm perceptions of vaping relative to smoking (P > 0.05 for most contrasts, adjusting for age and sex). Certain features and types of vaping products [higher nicotine concentrations, more e-liquid consumed and salt (versus freebase) nicotine]were perceived to confer greater health harms among a sample of UK adults who smoked and/or vaped. Findings are consistent with pervasive misperceptions that nicotine is a major cause of harm, although e-liquid volume is likely to contribute to harms.

Constraining electronic nicotine delivery systems (ENDS) nicotine dose by controlling nicotine flux at a limited puff duration.

Nicotine flux, the rate of electronic nicotine delivery system (ENDS) nicotine emission, is important in determining ENDS abuse liability. However, flux does not account for user behavior, including puff duration. Along with nicotine flux, puff duration limits the dose of nicotine that can be inhaled. Controlling both flux and puff duration allows regulators to constrain nicotine dose effectively. This study examined the effects of differing ENDS nicotine fluxes (by manipulating liquid nicotine concentration and holding device power constant), with user puff duration limited to 2 s. Participants (N = 32) completed four sessions, each session differing by nicotine flux (no flux, low flux, cigarettelike flux, and high flux conditions). Participants completed two ENDS use bouts in each session while puff duration was limited to 2 s. Plasma nicotine concentration, heart rate, and subjective effects were measured. At higher flux, higher plasma nicotine concentration and higher heart rate were observed. Moreover, higher fluxes decreased ratings of craving and urge to use nicotine and increased positive subjective effects, such as calmness. This study demonstrates that by manipulating nicotine flux and limiting puff duration, nicotine dose can be controlled. Subsequent research should demonstrate the effects of manipulating puff duration systematically. Results underscore the importance of targeting both flux and puff duration for ENDS regulation, intended to reduce abuse liability while maintaining the potential to facilitate transitions from cigarettes to ENDS. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Estimating human pharmacokinetic parameters forelectronic nicotine delivery system products from chemical analyses of their aerosols.

The ability of Electronic Nicotine Delivery Systems (ENDS) to deliver nicotine is central to their function to substitute for cigarettes, allowing people who smoke to switch away from smoking, thus reducing their exposure to harmful chemicals in cigarette smoke. The nicotine concentration in ENDS e-liquid has proved to be a poor predictor of nicotine uptake in users. Using meta-analytic methods to analyze 12 pharmacokinetic studies of nicotine-salt closed-system ENDS, this paper examines whether the mass of nicotine/puff of aerosol can predict Cmax in pharmacokinetic studies. Cmax values were available for 38 products, in 58 use conditions (including both controlled [3s] and ad libitum puffing), comprising 1769 participant observations. Nicotine/puff data reflected chemical analyses of aerosol obtained under nonintense (3s) or intense (6s) machine puffing. Meta-regression analyses (weighted by reliability of Cmax estimate) assessed the relationship of nicotine/puff to Cmax. In some models, empirical data were used to impute the variation in Cmax or the nicotine/puff value under intense puffing. In simple linear models, Cmax was significantly associated with nicotine/puff under all combinations of intense/nonintense and controlled/ad-libitum conditions, with R2 values of 0.71-0.77. More complex models based on quadratic effects or log[nicotine/puff] did not generally improve upon more parsimonious linear models. Application of the model illustrates the divergence between nicotine concentration in e-liquids and expected Cmax when other ENDS parameters vary. The meta-analytic model may have utility in settings where clinical pharmacokinetic data are not available, including product development.

Nicotine Dependency Levels Among Adult Electronic Cigarette Smokers in Jeddah, Saudi Arabia: An Analytical Cross-Sectional Study.

Electronic cigarettes (ECs) are a recent method to deliver nicotine with less harmful effects than traditional cigarettes. Studying nicotine dependence in adult EC users is a crucial area, but few measures are available to evaluate nicotine dependence induced by EC. Our study aims to estimate the levels of nicotine dependency among adult EC smokers using a modified Fagerström Test of Nicotine Dependence (e-FTND) in Jeddah, Saudi Arabia, and to identify EC-associated sociodemographic and smoking-related factors affecting nicotine dependency. An analytical cross-sectional study was conducted on adults 18 years of age and older in Jeddah, Saudi Arabia, from December 2023 to March 2024. Data were collected from the participants using a pre-tested structured self-administered questionnaire, and nicotine dependence was assessed using the modified e-FTND. Descriptive statistics such as frequency, mean, and standard deviation were applied. Chi-square was used to assess the association between categorical variables. Ordinal regression was used to predict the nicotine dependency levels with different variables. A total of 344 participants were included in the study. The mean e-FTND score for EC users was 4.14 ± 2.45. Females had a lower likelihood of experiencing higher dependence compared to males (OR = 0.52, 95% CI: 0.32, 0.85). Using ECs for more than three years was associated with higher odds of increased dependence (OR = 3.18, 95% CI: 1.28, 7.98; p < 0.001). The use of Pod system devices lowered the odds of developing high nicotine dependence (OR = 0.32, 95% CI: 0.13, 0.75; p = 0.01) compared to Iqos device users, while mechanical Mod device users exhibited a trend towards higher dependence, although it was not statistically significant. Nicotine concentration in ECs had a significant impact on the degree of nicotine dependence. Higher concentrations were associated with increased odds of higher dependence (12-18 mg: OR = 3.26, 95% CI: 1.55, 6.91; >18 mg: OR = 4.53, 95% CI: 2.37, 8.75; p < 0.001). Most exclusive EC users in the study developed a moderate nicotine dependence level. The EC device type and nicotine concentration were significant drivers of nicotine dependence. Additionally, the personal characteristics of the users, such as male gender and duration of use, were associated with a higher risk of dependence. An in-depth understanding of the magnitude of nicotine dependence among EC users will enhance the opportunity for tailored health-enhancing interventions and policies.

Perceptions of the Addictiveness of Low-Nicotine Cigarettes Versus Typical Cigarettes and Exposure to Tobacco Industry-Sponsored Corrective Campaign

Background In 2017, the U.S. Food and Drug Administration (FDA) announced a regulatory plan to reduce the nicotine content of cigarettes. This study examines the association of exposure to industry-sponsored corrective statements on perceptions of the addictiveness of low-nicotine cigarettes relative to typical cigarettes within the general US population. Methods The study comprised 4975 US adult respondents of the 2019 Health Information National Trends Survey (HINTS 5, Cycle 3). Multinomial logistic regression models were used to examine associations between exposure to tobacco industry corrective messages and perceptions of the addictiveness of low-nicotine cigarettes relative to typical cigarettes. Results In the overall population, 4.1% reported that low-nicotine cigarettes were much more addictive than typical cigarettes, 67.5% said they were equally addictive, while 28.4% reported they were slightly/much less addictive. Adults exposed to industry-sponsored corrective messages had higher odds of perceiving low-nicotine cigarettes as equally addictive as typical cigarettes (aOR 1.57; 95% CI, 1.13–2.19) than those who saw no corrective messages. Those exposed to the corrective messages specifically about the addictiveness of smoking and nicotine had higher odds of perceiving low-nicotine cigarettes as equally addictive as typical cigarettes (aOR, 1.73; 95% CI, 1.07–2.81) compared to those who saw no corrective message. Conclusions Our findings suggest that exposure to court-ordered tobacco industry corrective statements may have reinforced perceptions on the addictive potential of nicotine. However, study findings indicate a need for campaigns specifically tailored to address misperceptions observed in this study.

Evaluating trends in recruitment challenges in vape shop research, e-cigarette product characteristics and use among shop customers from 2019 to 2023: A mixed-methods study.

Brick-and-mortar vape shops specialize in the sale of e-cigarettes and remain a primary source for purchasing emerging e-cigarette products. New regulatory policies have been implemented at local-, state- and federal-level; the retail environment at vape shops and product preferences among vape shop customers shifted accordingly. From 2019 to 2023, we collected anonymous interview data from vape shop customers (n=572) from 83 vape shops in Southern California. We aggregated the data by month and treated each month as the unit of analysis to document changes in recruitment efforts among the vape shops in relation to major policy implementations over 4 years. We also examined the systematic fluctuations and trends in customers' e-cigarette product preferences and nicotine content in these products. The monthly average shop-level consent rate was 52.9% (SD=8.7), with an overall decreasing trend over time. It was necessary for our data collection team to approach a greater number of vape shops to obtain consent with implementation of various state and federal tobacco regulations and following COVID-19. We observed an increase in the purchase of disposable products and nicotine concentrations in the products, while the average use frequency remained the same. Our findings demonstrated that user preferences, product characteristics and challenges in research involving vape shops are closely associated to changes in regulations. We documented a dramatic increase in nicotine concentration in products. Future policies restricting the amount of nicotine in tobacco products at the federal level are necessary to protect consumers from further nicotine addiction. This study provides documentation over time of the drastic increases in nicotine concentration among e-cigarette users as a result of the fluctuations in the product market. Regulating nicotine content in tobacco products could safeguard against further unsafe modifications in e-cigarettes and other types of tobacco products.

Oral tobacco-free nicotine products: Quality and safety during storage

Oral non-tobacco nicotine products have gained enormous popularity in recent years. The countries of the Eurasian Economic Union also produce and sell this type of innovative but poorly studied goods. As a result, the safety profile and quality of such products as nicotine poaches require urgent comprehensive research. This study featured the changes in quality of nicotine poaches during storage, i.e. nicotine content, water activity, and microbiological index. The research featured nicotine poaches of several popular brands. The authors used standard research methods; the experiments were performed in the laboratory for chemistry and quality control, Institute of Tobacco, Makhorka, and Tobacco Products, Krasnodar, and at the Department of Bioorganic Chemistry and Technical Microbiology, Kuban State Technological University, Krasnodar. The water activity was 0.8911–0.9502 Aw at the initial stage and remained stable in most samples even after six months of storage. Velo Freeze was the only brand to show significant variations in water activity. The nicotine content was 10.115–12.950 mg/g at the initial stage. Only four samples maintained the initial values after six months of storage. The fluctuations of nicotine content were also mentioned by the manufacturer. The microbiological profile remained stable during the six months of storage and met the requirements for similar products, i.e., chewing gum and unglazed caramel. The project needs further research because the qualitative characteristics of nicotine poaches provided rather unambiguous results. Our study will help develop state standards for oral nicotine products. The results obtained will be used to formulate proposals to the organizations responsible for the future Technical Regulations of the Eurasian Economic Union for nicotine products.

Characteristics of Adolescents’ and Young Adults’ Exposure to and Engagement with Nicotine and Tobacco Product Content on Social Media

To inform policy and messaging, this study examined characteristics of adolescents’ and young adults’ (AYAs’) exposure to and engagement with nicotine and tobacco product (NTP) social media (SM) content. In this cross-sectional survey study, AYAs aged 13–26 (N=1,163) reported current NTP use, SM use frequency, and exposure to and engagement with SM content promoting and opposing NTP use (i.e. frequency, source[s], format[s], platform[s]). Participants who used NTPs (vs. did not use) were more likely to report having seen NTP content (p-values<.001). Prevalent sources were companies/brands (46.6%) and influencers (44.4%); prevalent formats were video (65.4%) and image (50.7%). Exposure to content promoting NTP use was prevalent on several popular platforms (e.g. TikTok, Instagram, Snapchat); exposure to content opposing NTP use was most prevalent on YouTube (75.8%). Among those reporting content engagement (i.e. liking, commenting on, or sharing NTP content; 34.6%), 57.2% engaged with influencer content. Participants reported engaging with content promoting and opposing NTP use on popular platforms (e.g. TikTok, Instagram, YouTube). Participants with (versus without) current NTP use were significantly more likely to use most SM platforms and to report NTP content exposure and engagement (p-values<.05). Results suggest that NTP education messaging and enforcement of platforms’ content restrictions are needed.

Small pouches, but high nicotine doses-nicotine delivery and acute effects after use of tobacco-free nicotine pouches.

Tobacco-free nicotine pouches are new nicotine products for oral consumption. They can contain very high nicotine amounts that have not been addressed with clinical studies yet. Thus, nicotine delivery, effects on craving, and side effects were assessed using pouches with up to 30mg nicotine. In this single-center, five-arm, crossover study, 15 regular cigarette smokers consumed tobacco-free nicotine pouches from different brands with 6, 20, and 30mg for 20min. Comparators were nicotine-free pouches and tobacco cigarettes. At baseline and predefined time points over a study period of 240min, plasma nicotine concentrations, effects on cigarette craving, and side effects were assessed. Cardiovascular parameters including arterial stiffness were measured using a MobilOGraph. Consumption of 30mg nicotine pouches has led to a higher nicotine uptake compared with the cigarette (Cmax: 29.4 vs 15.2ng/mL; AUC: 45.7 vs 22.1ng/mL × h). Nicotine uptake in the acute phase was rapid during use of the 30mg pouch and cigarette. Extraction rate of nicotine differed between pouches. Use of all products has reduced acute cigarette craving, even the nicotine-free pouch. During consumption of the cigarette and the pouches with 20 and 30mg, heart rate increased about 27, 12, and 25 bpm, respectively. Parameters for arterial stiffness were elevated and all pouches have induced mouth irritations. The pouches with 30mg nicotine had overall the strongest side effects and may induce addiction. As craving was also reduced by products with less nicotine, it is questionable whether such high nicotine contents should be allowed on the market. A limit of nicotine content is warranted. The nicotine release rate varies across products and needs to be known to estimate the nicotine delivery.

How healthcare providers and the right information may play a critical role in quitting success among smokers interested in using e-cigarettes for quitting: Results from a survey of U.S adults.

Promoting smoking cessation is a global public health priority. E-cigarettes are increasingly being used by individuals to try quitting smoking. Identifying sources and types of information available to adults who are trying to quit, and the impact of this information during a quit attempt, is critical to augment the potential public health benefit of e-cigarettes for reducing cigarette smoking. US adults (N = 857) who reported using e-cigarettes in a recent smoking cessation attempt completed an anonymous, cross sectional, online survey. We examined sources of information and type of information received when using e-cigarettes to quit smoking and their associations with the duration of abstinence achieved. The two most commonly reported information sources were friends (43.9%) and the internet (35.2%), while 14.0% received information from a healthcare provider. People received information on type of device (48.5%), flavor (46.3%), and nicotine concentration (43.6%). More people received information about gradually switching from smoking to vaping (46.7%) than abruptly switching (30.2%). Obtaining information from healthcare providers (β (SE) = 0.16 (0.08), p = 0.04), getting information about abruptly switching to e-cigarettes (β (SE) = 0.14 (0.06), p = 0.01) and what nicotine concentrations to use (β (SE) = 0.18 (0.05), p = 0.03) were associated with longer quit durations. Amidst the growing popularity of e-cigarettes use for quitting smoking, our results highlight common sources of information and types of information received by individuals. Few people received information from healthcare providers indicating a gap in cessation support that can be filled. Providing information about immediate switching to e-cigarettes and nicotine concentrations to use may help in increasing quit rates and duration.

Nicotine-mediated therapy for Parkinson's disease in transgenic Caenorhabditis elegans model.

Parkinson's disease resultant in the degeneration of Dopaminergic neurons and accumulation of α-synuclein in the substantia nigra pars compacta. The synthetic therapeutics for Parkinson's disease have moderate symptomatic benefits but cannot prevent or delay disease progression. In this study, nicotine was employed by using transgenic Caenorhabditis elegans Parkinson's disease models to minimize the Parkinson's disease symptoms. The results showed that the nicotine at 100, 150, and 200 μM doses reduced degeneration of Dopaminergic neurons caused by 6-hydroxydopamine (14, 33, and 40%), lowered the aggregative toxicity of α-synuclein by 53, 56, and 78%, respectively. The reduction in food-sensing behavioral disabilities of BZ555 was observed to be 18, 49, and 86%, respectively, with nicotine concentrations of 100 μM, 150 μM, and 200 μM. Additionally, nicotine was found to enhance Daf-16 nuclear translocation by 14, 31, and 49%, and dose-dependently increased SOD-3 expression by 10, 19, and 23%. In summary, the nicotine might a promising therapy option for Parkinson's disease.

E-cigarette use, perceived risks, attitudes, opinions of e-cigarette policies, and associated factors among Thai university students.

Although many countries, including Thailand, currently ban the sale of e-cigarettes, their use continues to rise, especially among young adults. Since the study of e-cigarette use among university students is limited, this study aimed to determine factors associated with e-cigarette use and explore university students' attitudes toward e-cigarettes, perceived risk, and opinion of e-cigarette policies. This cross-sectional study was conducted among undergraduate students using convenience sampling in a university, in central Thailand from November 2022 to February 2023. A self-administered online questionnaire was distributed to 19 faculties representing health sciences, science and technology, social and arts faculties, and the International College. A total of 548 students completed the online questionnaire, and 20.4% reported ever using e-cigarettes, while 40% of e-cigarette users were unsure about the nicotine content. About 28% agreed, and 22% were unsure whether e-cigarettes could help quit smoking. Most students perceived that e-cigarettes are addictive and harmful, while about half of the participants agreed with the policy related to e-cigarettes in Thailand. Students with positive attitudes towards e-cigarettes were more likely to use e-cigarettes (AOR=1.15; 95% CI: 1.08-1.22), and those with lower perceived risk (AOR=0.89; 95% CI: 0.82-0.96) and who disagreed with e-cigarettes policy (AOR=0.93; 95% CI: 0.89-0.97) were more likely to use e-cigarettes. Personal income and having friends who use e-cigarettes were the significant predictors for e-cigarette use, while studying in the faculty of science and technology was a predictor of using e-cigarettes last month. Although the perceived risk was high, about half of the students thought that e-cigarettes could help them quit smoking and were unsure or disagreed with e-cigarette banning policies. Attitude, perceived risk, policy opinions, personal income, and having friends who used e-cigarettes, were associated with e-cigarette use. Thus, correcting misunderstandings and increasing risk perceptions about e-cigarettes must be advocated among university students.

Cigarette smoking and cognitive task performance: Experimental effects of very-low nicotine-content cigarettes.

Reductions in the nicotine content of cigarettes decrease smoking rate and dependence severity, but effects on cognition are less well established. The potential impacts of very-low nicotine-content (VLNC) cigarettes on cognitive task performance must be evaluated, especially in vulnerable populations. The aim of the present study is to experimentally examine the effects of VLNC cigarettes on cognitive performance. Adults who smoked daily (n = 775) from three vulnerable populations (socioeconomically disadvantaged reproductive-age women, individuals with opioid use disorder, affective disorders) were examined. Participants were randomly assigned to normal nicotine content (NNC; 15.8 mg nicotine/g tobacco) or VLNC (2.4 mg/g or 0.4 mg/g) cigarettes for 12 weeks. Response inhibition (stop-signal task), working memory (n-back task; n of 2-n of 0), and cognitive interference (nicotine Stroop task) were assessed at baseline, 2, 6, and 12 weeks. Results were analyzed using mixed-model repeated-measures analyses of variance. Extended exposure to VLNC cigarettes produced no significant changes in any measure of cognitive performance compared to NNC cigarettes. Over weeks, response times on the n-back task decreased across doses. No significant effects were observed on the stop-signal or nicotine Stroop tasks. All three vulnerable populations performed comparably on all three cognitive tasks. Extended exposure to VLNC cigarettes produced no impairments in cognitive performance on any of the assessed tasks compared to NNC cigarettes. These findings are consistent with the larger literature detailing other consequences following exposure to VLNC cigarettes and are encouraging for the adoption of a nicotine-reduction policy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Dual Regulation of Nicotine on NLRP3 Inflammasome in Macrophages with the Involvement of Lysosomal Destabilization, ROS and α7nAChR.

Nicotine, the primary alkaloid in tobacco products, has been shown to have immunoregulatory function in at least 20 diseases. The biological mechanism of action of nicotine immunoregulation is complex, resulting in an improvement of some disease states and exacerbation of others. Given the central role of the NLRP3 inflammasome in macrophages among multiple inflammatory diseases, this study examined how nicotine alters NLRP3 inflammasome activation in macrophages. NLRP3 inflammasome activation was examined mechanistically in the context of different nicotine dosages. We show NLRP3 inflammasome activation, apoptosis-associated speck-like protein (ASC) expression, caspase-1 activity and subsequent IL-1β secretion were positively correlated with nicotine in a dose-dependent relationship, and destabilization of lysosomes and ROS production were also involved. At high concentrations of nicotine surpassing 0.25mM, NLRP3 inflammasome activity declined, along with increased expression of the anti-inflammatory Alpha7 nicotinic acetylcholine receptor (α7nAChR) and the inhibition of TLR4/NF-κB signaling. Consequently, high doses of nicotine also reduced ASC expression, caspase-1 activity and IL-1β secretion in macrophages. Collectively, these results suggest a dual regulatory function of nicotine on NLRP3 inflammasome activation in macrophages, that is involved with the pro-inflammatory effects of lysosomal destabilization and ROS production. We also show nicotine mediates anti-inflammatory effects by activating α7nAChR at high doses.

Evaluating the Role of Nicotine Stereoisomer on Nicotine Pouch Abuse Liability: A Randomized Crossover Trial.

Many oral nicotine pouch (ONP) brands use synthetic nicotine, which typically contains a racemic (50:50) mixture of nicotine's two stereoisomers: S-nicotine and R-nicotine. Because tobacco-derived nicotine contains more than 99% S-nicotine, the effects of R-nicotine in humans are not well known. We compared systemic nicotine exposure and product appeal of ONPs containing more than 99% S-nicotine versus racemic nicotine. N = 18 adult smokers (Mage = 45 years, 66.7% male, 77.8% White) enrolled in a three-visit single-blind, randomized crossover study. During each visit, participants used one wintergreen-flavored, 3mg nicotine ONP for 30min following at least12h nicotine abstinence. Study ONP #1 contained more than 99% S-nicotine and the other two study ONPs contained racemic nicotine (collapsed for analyses). Plasma nicotine assessments and measures of withdrawal relief occurred at t = 0, 5, 15, 30, 60, and 90min; measures of product appeal were assessed following ONP use. Using the ONP with more than 99% S-nicotine resulted in greater plasma nicotine concentration from 15 to 90min (p < .0001) and greater maximum plasma nicotine concentration than the ONPs with racemic nicotine (M = 9.9ng/mL [SD = 2.5] vs. M = 5.7ng/mL [SD = 2.8], respectively; p < .0001). Product liking and withdrawal relief were similar across ONPs, although participants reported more "bad effects" when using the ONP with more than 99% S-nicotine. Participants reported few subjective differences in ONPs according to nicotine stereoisomer, but plasma nicotine concentration was greater for ONPs using more than 99% S-nicotine. ONPs with more than 99% S-nicotine (vs. racemic nicotine) might be better substitutes for cigarettes, but research into other ONP characteristics (eg flavors, freebasenicotine) is needed to inform regulation. Little is known about the effects of racemic (vs. S-) nicotine in humans. In a sample of adults who smoke cigarettes, we identified that oral nicotine pouches containing racemic nicotine exposed participants to less nicotine than oral nicotine pouches containing only S-nicotine, but both types of oral nicotine pouches held similar, moderate appeal. Additional research evaluating the roles that flavorings, total nicotine concentration, and freebase nicotine play in the abuse liability of oral nicotine pouches would inform comprehensive product regulations to support public health.

Direct Extraction and Determination of Free Nicotine in Cigarette Smoke.

The accurate determination of the free nicotine content in cigarette smoke is crucial for assessing cigarette quality, studying harm and addiction, and reducing tar levels. Currently, the determination of free nicotine in tobacco products primarily relies on methods such as pH calculation, nuclear magnetic resonance (NMR) spectroscopy, headspace solid-phase microextraction (HS-SPME), and traditional solvent extraction. However, these methods have limitations that restrict their widespread application. In this study, the free nicotine in cigarette smoke was directly extracted by using cyclohexane according to the traditional solvent extraction method and detected via gas chromatography-mass spectrometry. Compared with the traditional two-phase solvent extraction, our experimental method is easy to execute and eliminates the influence of aqueous solutions on the original distribution of nicotine in cigarette smoke particulate matter. Furthermore, the presence of protonated nicotine in tobacco does not affect the determination. Compared with HS-SPME and NMR spectroscopy, our approach, which involves solvent extraction followed by chromatographic separation and instrumental detection, offers simplicity, improved precision, better detection limits, and reduced interference during the instrumental detection stage. The standard addition recoveries in the conducted experiment ranged from 96.2% to 102.5%. The limit of detection was 2.8 μg/cig, and the correlation coefficient (R2) for the quadratic regression of the standard curve exceeded 0.999. The relative standard deviation for parallel samples was between 1.7% and 3.4% (n = 5), fully meeting the requirements for the determination of free nicotine in cigarette smoke. Analysis of cigarette samples from 38 commercially available brands revealed that the content of free nicotine ranged from 0.376 to 0.716 mg/cig, with an average of 0.540 mg/cig, and free nicotine accounted for 39.1%-88.8% of the total nicotine content.

Immune Cell Profile in Young Adults who Regularly Use E-cigarettes and the Role of Nicotine

Background: Cigarette smoking results in altered immune cell function and associated systemic inflammation, as observed in chronic obstructive pulmonary disease (COPD). Electronic (e-) cigarettes are novel, popular tobacco products frequently advertised as a safer alternative to traditional cigarettes; however, the effects of their regular use on immune cell function are currently unknown. Thus, the purpose of this study was to investigate the impact of e-cigarette usage and the role of nicotine on the immune cell profile of young, regular users. Methods: Twenty-five young, apparently healthy, regular users of e-cigarettes (EU, age: 23±3 y.) and twenty-two non-users (NU, age: 23±4 y.) participated in this study. A fasted venous blood sample was obtained from all participants for a complete blood count and nicotine concentrations. EU were randomized to either nicotine or nicotine-free products for fourteen days and completed a second assessment to investigate changes in the immune cell profile based on either increased (+C; n=11) or decreased (-C; n=9) nicotine usage accessed via cotinine levels. For comparison, the same assessments were completed in a group of 13 patients with a diagnosis of COPD (67±9 y., GOLD Stage II-IV). Results: Regular users of e-cigarettes exhibit significantly higher eosinophils (absolute, p=0.008, percentage, p=0.042) and platelets ( p=0.018) when compared to non-users but similar ( p≥0.431) to patients with COPD. White blood cell, neutrophil, monocyte, and lymphocyte counts were similar between the EU and NU. After fourteen days, despite significant changes in nicotine (Δ+C=+2±4 vs. Δ-C=-3±4 ng/mL, p=0.014) and cotinine (Δ+C=+28±27 vs. Δ-C=-141±120 ng/mL, p=0.001) between +C and -C groups, no differences in the immune cell profiles were observed. To note, no association between immune cells and nicotine levels at baseline or follow-up (nicotine: r≤0.352; p≥0.122; cotinine: r≤0.310; p≥0.126). Conclusions: Results of the study suggests that regular users of e-cigarettes present with altered immune cell profile in eosinophils and platelets when compared to non-users. The elevated immune cell markers were comparable to observed values in patients with COPD and have been associated with adverse effects on pulmonary and cardiovascular health. In addition, the elevated immune cell profile was not related to changes in nicotine, inferring that other e-liquid components may have an effect on innate immunity. Future studies are warranted to investigate the long-term effects of e-cigarette use and their components on immune cell profile. Supported in part by a Rapid Response Project NIDA/FDA (PRM). This is the full abstract presented at the American Physiology Summit 2024 meeting and is only available in HTML format. There are no additional versions or additional content available for this abstract. Physiology was not involved in the peer review process.

Assessing Impact of Manual Topping and Suckericide Application at Different Stages on FCV Tobacco Quality and Yield

Tobacco (Nicotiana tabacum L.) topping is one of the essential practice to obtain good quality and adequate yield. The suckericide (Flumetralin as a best herbicide and plant growth regulator). For the purpose to compare topping as manual and herbicide application the experiment was conducted on flue cured Virginia (FCV) tobacco at Tobacco Research Station, Khan Ghari, Mardan during 2021-2022. The experiment was conducted in RCB design with three replications and five treatments (Control, Manual de-suckering, 1000, 1200, 1500 ml of Flumetralin ha-1). Treatments were applied at three stages (button stage, early flowering stage and late flowering stage). The data revealed that topping timing and maximum dose (1500 ml ha-1) of (Flumetralin) resulted maximum (896 cm-2) leaf area, less number (14) of sucker plant-1, lower (132 g) green weight and dry weight (20.30 g) of sucker plot-1, more cured weight (5.08 kg) of leaves plot-1 and maximum yield (3038) kg ha-1, lower nicotine contents (2.26) and less sugar contents (16.24) at button stage. Moreover, Flumetralin application on at button stage resulted less sucker growth and enhanced leaf yield. I suggest that the tobacco K399 with the application of suckericide and growth regulator (Flumetralin) have the potential to incorporate in further breeding program for low content of nicotine, reduced sugar content and high yield.

Consumption of hookahs, e-cigarettes, and classic cigarettes and the impact on medically assisted reproduction treatment

Smoking of classic cigarettes has been well-established as a health risk factor, including cardiovascular, neurological, and pulmonary diseases. Adverse effects on human reproduction have also been shown. Smokers are assumed to have a significantly lower chance of pregnancy, however, the impact of smoking on medically assisted reproduction (MAR) treatment outcomes is controversial. Moreover, smoking habits have changed during the last decades since e-cigarettes and hookahs, or water pipes, have become very popular, yet little is known regarding vaping or hookah-smoking patients undergoing MAR treatments. This prospective study aimed to examine the presence of benzo[a]pyrene, nicotine, and its main metabolite, cotinine, in human follicular fluid (FF) in non-smoking, smoking, and vaping/hookah-smoking patients and to evaluate the impact on female fertility. Human FF samples were collected from 320 women subjected to intracytoplasmic sperm injection (ICSI) cycles due to male subfertility. Gas chromatography combined with mass spectrometry was used to analyse the presence of benzo[a]pyrene, nicotine, and cotinine. A questionnaire was provided to assess patient consumption behaviour and to identify (1) non-smoking patients, (2) patients who consumed cigarettes, and (3) patients with exclusive consumption of e-cigarettes or hookahs. Data were analysed using linear and logistic regression, Fisher’s exact test, and the Mann–Whitney U Test. Nicotine was present in 22 (6.8%) and cotinine in 65 (20.3%) of the 320 samples. The nicotine and cotinine concentrations per sample ranged from 0 to 26.3 ng/ml and 0–363.0 ng/ml, respectively. Benzo[a]pyrene was not detectable in any of the samples analysed. Nicotine and cotinine were also present in the FF of patients with exclusive consumption of e-cigarettes or hookahs. The clinical pregnancy rate, fertilization and maturation rates, and number of oocytes per oocyte pick-up were not statistically significantly different between non-smoking, smoking, or vaping/hookah-smoking patients. Smoking and the accumulation of smoking toxins in the FF have no impact on the outcome of MAR treatments—neither the clinical pregnancy rate, maturation and fertilization rates, nor the number of retrieved oocytes were affected. For the first time, nicotine and cotinine were quantified in the FF of patients exclusively vaping e-cigarettes or smoking hookahs. Since vaping liquids and hookah tobaccos contain potentially harmful substances, other adverse effects cannot be excluded.Trial registration ClinicalTrials.gov Identifier: NCT03414567.