Differences in Exposure to Nicotine, Tobacco-Specific Nitrosamines, and Volatile Organic Compounds among Electronic Cigarette Users, Tobacco Smokers, and Dual Users from Three Countries.

Country-level differences in nicotine vaping products used and biomarkers of exposure among long-term e-cigarette users and dual users remain understudied. This cross-sectional study was conducted in 2014 in the United States (n = 166), United Kingdom (n = 129), and Poland (n = 161). We compared patterns of tobacco product use and nicotine and toxicant exposure among cigarette-only smokers (n = 127); e-cigarette-only users (n = 124); dual users of tobacco cigarettes and e-cigarettes (n = 95); and non-users (control group, n = 110) across three countries using mixed-effects linear regression. Compared with cigarette smokers, e-cigarette-only users had lower levels of toxicant biomarkers, but higher levels of nicotine biomarkers. Dual users had higher levels of toxicant biomarkers than e-cigarette-only users but similar levels to cigarette-only smokers. E-cigarette users in Poland, who overwhelmingly used refillable tank devices, exhibited greater levels of nicotine, and toxicant biomarkers relative to e-cigarette users in US/UK. Despite smoking fewer cigarettes, dual users from Poland exhibited similar levels of nicotine biomarkers compared with UK dual users, but higher than US dual users. Country-level differences in e-cigarette devices used and smoking behaviors (e.g., intensity) may contribute to differences in biomarker levels among users of the same products residing in different countries.

Exclusive versus dual use of tobacco and electronic cigarettes among adolescents in Poland, 2010-2016.

Globally, electronic cigarette (e-cigarette) use among adolescents has increased, along with concerns about potential health implications from exclusive and concurrent tobacco and e-cigarette use (i.e., "dual use"). This study used data from a cross-sectional survey administered to 5708 students aged 15-19 in secondary and technical schools throughout two regions of Poland. Data from 2010-2011 (n = 1760); 2013-2014 (n = 1970) and 2015-2016 (n = 1978) were analyzed to assess changes in use of cigarettes and e-cigarettes from 2010-2016, and correlates of exclusive and dual use, daily use, and intensity of product use from 2013-2016. In this sample, e-cigarette trial and past 30-day exclusive e-cigarette use significantly increased over time (2010-2011: 2%; 2013-2014: 8%; 2015-2016: 11% (p < .05)). Dual use increased from 2010-2011 (4%) to 2013-2014 only (23%, p < .05); and remained stable from 2013-2014 to 2015-2016 (24%, p = .60). Most dual users reported using cigarettes before trying e-cigarettes (82% in 2013-2014, 76% in 2015-2016). Analyses comparing dual users to exclusive users showed significant differences in frequency and intensity of product use, similar findings were observed within dual users. Following the introduction of e-cigarettes, both total tobacco use and total cigarette use increased. Among youth in Poland, e-cigarettes do not seem to replace conventional cigarettes, but instead contribute to a more diverse array of available products from which youth can experiment.

Youth Access to Electronic Cigarettes in an Unrestricted Market: A Cross-Sectional Study from Poland.

Background: Electronic cigarette (e-cigarette) use among youths in Poland has become very popular. The aim of this study was to identify the potential points of access to these products by students aged 16⁻17 years old before implementation of sales restrictions to minors in Poland in November 2016. Methods: A school-based, cross-sectional survey was administered in 2015⁻2016 in 21 secondary/technical schools across two regions of Poland. Analyses focused on 341 students aged 16⁻17 years old who reported their past 30-day use of e-cigarettes. Pearson Chi-square analyses were utilized to examine the associations between access-related items, e-cigarette use and demographics. Results: Among youth e-cigarette users, the most common access to their first e-cigarette was from a friend (38%), followed by purchasing from vape shops (26%). Similar patterns emerged when the students were asked about their access to the currently used e-cigarette. Most youths reported no difficulty in purchasing cartridges/e-liquid containing nicotine (90%). The majority of users (52%) reported buying such products in vape shops. Conclusions: Prior to implementing age-related sales restrictions, youth access to e-cigarettes and paraphernalia did not pose any significant barriers. Poland's introduction of a new age limit on e-cigarette sales may help to limit the number of youths who purchase e-cigarettes from vape shops.

Nicotine emissions from electronic cigarettes: Individual and interactive effects of propylene glycol to vegetable glycerin composition and device power output.

INTRODUCTION: The power output of e-cigarettes varies considerably, as does the composition of liquids used with these products. Most e-cigarette liquids contain two primary solvents: propylene glycol (PG) and vegetable glycerin (VG). The primary aim of this study was to examine the extent to which PG and VG composition and device power interact with each other to influence e-cigarette nicotine emissions. METHODS: Aerosols were generated using a 2nd generation e-cigarette and an automatic smoking machine. Nicotine was measured in aerosols, via gas chromatography, produced from three solutions containing pure PG, pure VG, or a mixture of both solvents (50:50) across three different power settings (4.3, 6.7, and 9.6 W). RESULTS: At the lowest power setting, nicotine yield increased significantly as more PG was added to the solution. However, as device power was increased, differences in nicotine yield across liquids became less pronounced. At the highest power setting (9.6 W), nicotine yields did not differ across the three liquids examined. CONCLUSIONS: The present study demonstrated that the extent to which e-cigarette liquid PG and VG composition influences nicotine emissions is dependent on device power. Thus, device power may influence e-cigarette nicotine emissions to a greater degree relative to solvent concentrations.

Exposure to Nicotine and Selected Toxicants in Cigarette Smokers Who Switched to Electronic Cigarettes: A Longitudinal Within-Subjects Observational Study.

INTRODUCTION: Electronic cigarettes (e-cigarettes) are purported to deliver nicotine aerosol without any toxic combustion products present in tobacco smoke. In this longitudinal within-subjects observational study, we evaluated the effects of e-cigarettes on nicotine delivery and exposure to selected carcinogens and toxicants. METHODS: We measured seven nicotine metabolites and 17 tobacco smoke exposure biomarkers in the urine samples of 20 smokers collected before and after switching to pen-style M201 e-cigarettes for 2 weeks. Biomarkers were metabolites of 13 major carcinogens and toxicants in cigarette smoke: one tobacco-specific nitrosamine (NNK), eight volatile organic compounds (1,3-butadiene, crotonaldehyde, acrolein, benzene, acrylamide, acrylonitrile, ethylene oxide, and propylene oxide), and four polycyclic aromatic hydrocarbons (naphthalene, fluorene, phenanthrene, and pyrene). Changes in urine biomarkers concentration were tested using repeated measures analysis of variance. RESULTS: In total, 45% of participants reported complete abstinence from cigarette smoking at 2 weeks, while 55% reported continued smoking. Levels of total nicotine and some polycyclic aromatic hydrocarbon metabolites did not change after switching from tobacco to e-cigarettes. All other biomarkers significantly decreased after 1 week of using e-cigarettes (p < .05). After 1 week, the greatest percentage reductions in biomarkers levels were observed for metabolites of 1,3-butadiene, benzene, and acrylonitrile. Total NNAL, a metabolite of NNK, declined by 57% and 64% after 1 and 2 weeks, respectively, while 3-hydroxyfluorene levels declined by 46% at week 1, and 34% at week 2. CONCLUSIONS: After switching from tobacco to e-cigarettes, nicotine exposure remains unchanged, while exposure to selected carcinogens and toxicants is substantially reduced. IMPLICATIONS: To our knowledge, this is the first study that demonstrates that substituting tobacco cigarettes with an e-cigarette may reduce user exposure to numerous toxicants and carcinogens otherwise present in tobacco cigarettes. Data on reduced exposure to harmful constituents that are present in tobacco cigarettes and e-cigarettes can aid in evaluating e-cigarettes as a potential harm reduction device.

Dual use of electronic and tobacco cigarettes among adolescents: a cross-sectional study in Poland.

OBJECTIVES: Electronic cigarettes (e-cigarettes) are gaining in popularity among youth. While these products may be beneficial in adult smokers, the effect on young users of electronic and tobacco cigarettes (dual users) is unknown. The objective of this study was to assess the frequency of dual use among adolescents and to compare tobacco cigarette consumption among dual and exclusive tobacco cigarette users. METHODS: A cross-sectional survey of a sample of 2213 Polish students aged 16-18 conducted between December 2013 and February 2014. RESULTS: Overall, 21.8 % of students were dual users. Dual users were more likely to smoke tobacco cigarettes on a daily basis [adjusted odds ratio, AOR 3.54 (95 % CI 2.34-5.36) and less likely to smoke fewer cigarettes per day (AOR 0.27 (95 % CI 0.12-0.57)] than exclusive tobacco cigarette users. CONCLUSIONS: The frequency of dual use was higher than exclusive use of a single product among Polish adolescents. Young dual users do not smoke a lower number of tobacco cigarettes per day than exclusive tobacco cigarette users.

Influence of electronic cigarettes puffing regimes on amount of vaporized liquid.

E-cigarette (EC) was designed to provide less harmful alternative to conventional cigarettes. Along with growing popularity of ECs around the world, more products have appeared on the market. There are limited safety studies and data relating to potential toxicity of EC use. Therefore, there is strong need to gain thorough information about a composition of generated aerosol from ECs. Due to the fact that ECs settings and puffing regimes influence vapor and toxins generation, we decided to identify parameters that have the greatest impact on the aerosol yield. Material and Methods: We took into account three puffing parameters: puff volume, puff duration and interpuff interval. The study was divided into two stages. In a first stage puffing regimes were achieved in testing volunteers (14 men and 11 women). In a second one found parameters (volume, puffs durations, intervals between puffs) were used to mimic ECs use in laboratory settings to examine influence of different puffing regimes on aerosol yields. Smoking machine was used to generate aerosol (6 times for each set of parameters). Aerosol yield was represented as amount of e-liquid trapped on Cambridge filter. Results: The results of puffing regimes study among ECs users are presented as mean ± SD: puff volume [mL] 65 ± 49, puff duration [s] 2.8 ± 2.7 and intervals between puffs [s] 16 ± 40. Aerosol yields varied depending on the set puffing regimes. Conclusions: Our results indicate that the most important puffing parameters, which determine aerosol yield, are puffs duration and interpuff intervals. Puffs volume (between 41- 76 mL) has no influence on aerosol yield.

Changes in puffing behavior among smokers who switched from tobacco to electronic cigarettes.

INTRODUCTION: Nicotine intake from electronic cigarette (e-cigarettes) increases with user's experience. This suggests that smokers who switched from tobacco to electronic cigarettes compensate for nicotine over time to get as much nicotine as they need. One of the mechanisms by which smokers may compensate for nicotine is by modifying their puffing behavior. The aim of the study was to assess the changes in puffing behavior after switching from conventional to electronic cigarettes among regular smokers. MATERIALS AND METHODS: Twenty smokers (11 female, aged 31±10, CPD 16±8, FTND 4±3, and exhaled CO 16±17 (mean±SD)) who were naïve to e-cigarettes participated in this study. They were asked to substitute their regular tobacco cigarettes with first generation e-cigarettes (labeled 18mg nicotine) for two weeks. Puffing topography (number of puffs, puff volume, intervals between puffs, and average puff flow rate) was measured at the initial use (baseline), as well as after one and two weeks of product use. We tested changes in puffing topography outcomes using repeated measures ANOVA. RESULTS: We found that after one week of using e-cigarettes, participants significantly increased the average time they puffed on e-cigarettes from 2.2±0.1 (mean±SEM) to 3.1±0.3s (p<0.05). The average puff flow rate decreased from 30.6±2.3 to 25.1±1.8ml/s after one week of e-cigarette use (p<0.05). CONCLUSIONS: Our data show that smokers modify their puffing behavior after switching from tobacco to electronic cigarettes by taking longer and slower puffs. The potential reason for changing puffing behavior is to compensate for less efficient nicotine delivery from e-cigarettes.

Rise in electronic cigarette use among adolescents in Poland.

PURPOSE: Despite the potential negative health effects of electronic cigarettes (e-cigarettes), these devices are increasing in popularity worldwide, especially among youth. METHODS: We compared data from two cross-sectional studies conducted in Poland among students aged 15-19 years in 2010-2011 and 2013-2014. We tested differences between samples in the prevalence of e-cigarette use, tobacco cigarette smoking, and simultaneous use of both tobacco and e-cigarettes ("dual use") using a multilevel linear mixed model regression. RESULTS: We found that the current use of e-cigarettes among adolescents in Poland was significantly higher in the 2013-2014 sample than the 2010-2011 sample (29.9% vs. 5.5%, respectively; p < .05). Dual use of tobacco and e-cigarettes was also significantly higher (21.8% vs. 3.6%, respectively; p < .05). Interestingly, the prevalence of smoking tobacco cigarettes also increased (from 23.9% in 2010-2011 to 38.0% in 2013-2014; p < .05). CONCLUSIONS: Observed parallel increase in e-cigarette use and smoking prevalence does not support the idea that e-cigarettes are displacing tobacco cigarettes in this population.

Levels of selected carcinogens and toxicants in vapour from electronic cigarettes.

SIGNIFICANCE: Electronic cigarettes, also known as e-cigarettes, are devices designed to imitate regular cigarettes and deliver nicotine via inhalation without combusting tobacco. They are purported to deliver nicotine without other toxicants and to be a safer alternative to regular cigarettes. However, little toxicity testing has been performed to evaluate the chemical nature of vapour generated from e-cigarettes. The aim of this study was to screen e-cigarette vapours for content of four groups of potentially toxic and carcinogenic compounds: carbonyls, volatile organic compounds, nitrosamines and heavy metals. MATERIALS AND METHODS: Vapours were generated from 12 brands of e-cigarettes and the reference product, the medicinal nicotine inhaler, in controlled conditions using a modified smoking machine. The selected toxic compounds were extracted from vapours into a solid or liquid phase and analysed with chromatographic and spectroscopy methods. RESULTS: We found that the e-cigarette vapours contained some toxic substances. The levels of the toxicants were 9-450 times lower than in cigarette smoke and were, in many cases, comparable with trace amounts found in the reference product. CONCLUSIONS: Our findings are consistent with the idea that substituting tobacco cigarettes with e-cigarettes may substantially reduce exposure to selected tobacco-specific toxicants. E-cigarettes as a harm reduction strategy among smokers unwilling to quit, warrants further study. (To view this abstract in Polish and German, please see the supplementary files online.).

Nicotine levels in electronic cigarettes.

INTRODUCTION: The electronic cigarette (EC) is a plastic device that imitates conventional cigarettes and was developed to deliver nicotine in a toxin-free vapor. Nicotine in a solution is heated and vaporized when a person puffs through the device and is inhaled as a vapor into the mouth. The EC is a new product on the market and little is known about its safety and nicotine delivery efficacy. The aim of the study was to analyze nicotine levels in vapor generated from various EC brands and models. The study was designed to assess efficacy and consistency of various ECs in converting nicotine to vapor and to analyze dynamics of nicotine vaporization. METHODS: Sixteen ECs were selected based on their popularity in the Polish, U.K. and U.S. markets. Vapors were generated using an automatic smoking machine modified to simulate puffing conditions of real EC users. Nicotine was absorbed in a set of washing bottles with methanol and analyzed with gas chromatography. RESULTS: The total level of nicotine in vapor generated by 20 series of 15 puffs varied from 0.5 to 15.4 mg. Most of the analyzed ECs effectively delivered nicotine during the first 150-180 puffs. On an average, 50%-60% of nicotine from a cartridge was vaporized. CONCLUSIONS: ECs generate vapor that contains nicotine, but EC brands and models differ in their efficacy and consistency of nicotine vaporization. In ECs, which vaporize nicotine effectively, the amount inhaled from 15 puffs is lower compared with smoking a conventional cigarette.

Variations in nicotine yields between single cigarettes.

INTRODUCTION AND AIMS: It is beyond any doubt that nicotine yield in cigarettes as determined using standard ISO method bears almost no relation to smokers' actual intake. However, the ISO method is still in use in many countries where the government is responsible for controlling and monitoring cigarette quality. The aim of the study was to measure the nicotine yield in single cigarettes and to evaluate their statistical distribution among the same brand. MATERIALS AND METHODS: Nicotine yields were measured according to the ISO method in single cigarettes of the twenty most popular Polish brands of cigarettes. RESULTS: Relative standard deviation of nicotine yields in single cigarettes of the same brands varied from 16% to 34%. Relative differences between nicotine yields in a single cigarette of a particular brand and the mean value varied from -65% to +76%. DISCUSSION AND CONCLUSIONS: The results indicate high variation in nicotine yields between cigarettes of the same brand. Such variation might affect compensatory smoking. This provides another reason why yields estimated using the standard ISO method are potentially misleading to smokers. Further studies are needed to better understand the implications of within-brand variability in yields for tobacco product regulation.