Electronic cigarettes (e-cigs): views of aficionados and clinical/public health perspectives

Science and electronic cigarettes: current data, future needs

Electronic cigarettes (ECIGs), also referred to as electronic nicotine delivery systems or "e-cigarettes," generally consist of a power source (usually a battery) and heating element (commonly referred to as an atomizer) that vaporizes a solution (e-liquid). The user inhales the resulting vapor. Electronic cigarettes have been increasing in popularity since they were introduced into the US market in 2007. Many questions remain about these products, and limited research has been conducted. This review describes the available research on what ECIGs are, effects of use, survey data on awareness and use, and the utility of ECIGs to help smokers quit using tobacco cigarettes. This review also describes arguments for and against ECIGs and concludes with steps to move research on ECIGs forward.

Achieving appropriate regulations for electronic cigarettes

A growing body of scientific studies show that e-cigarettes may serve as an acceptable substitute for smoking tobacco cigarettes, thereby reducing or eliminating exposure to harmful elements in smoke. The success of e-cigarettes is such that sales of these products are rapidly gaining on traditional cigarettes. The rapidly evolving phenomenon is raising concerns for the health community, pharmaceutical industry, health regulators and state governments. Obviously, these products need to be adequately regulated, primarily to protect users. Depending on the form and intended scope, certain regulatory decisions may have diverse unintended consequences on public health and may face many different challenges. Ideally, before any regulations are enacted, the regulatory body will require sufficient scientific research to verify that a problem does exist, quantify the problem, explore all potential solutions including making no change at all, determine the possible consequences of each, and then select the solution that is best for public health. Here we present an overview on the existing and deeming regulatory decisions for electronic cigarettes. We challenge them, based on the mounting scientific evidence with the ultimate goal of proposing appropriate recommendations while minimizing potential unintended consequences of ill-informed regulation.

Electronic nicotine delivery systems ("e-cigarettes"): review of safety and smoking cessation efficacy

BACKGROUND AND OBJECTIVES

Cigarette smoking is common among cancer patients and is associated with negative outcomes. Electronic nicotine delivery systems ("e-cigarettes") are rapidly growing in popularity and use, but there is limited information on their safety or effectiveness in helping individuals quit smoking.

DATA SOURCES

The authors searched PubMed, Web of Science, and additional sources for published empirical data on safety and use of electronic cigarettes as an aid to quit smoking.

REVIEW METHODS

We conducted a structured search of the current literature up to and including November 2013.

RESULTS

E-cigarettes currently vary widely in their contents and are sometimes inconsistent with labeling. Compared to tobacco cigarettes, available evidence suggests that e-cigarettes are often substantially lower in toxic content, cytotoxicity, associated adverse effects, and secondhand toxicity exposure. Data on the use of e-cigarettes for quitting smoking are suggestive but ultimately inconclusive.

CONCLUSIONS

Clinicians are advised to be aware that the use of e-cigarettes, especially among cigarette smokers, is growing rapidly. These devices are unregulated, of unknown safety, and of uncertain benefit in quitting smoking.

IMPLICATIONS FOR PRACTICE

In the absence of further data or regulation, oncologists are advised to discuss the known and unknown safety and efficacy information on e-cigarettes with interested patients and to encourage patients to first try FDA-approved pharmacotherapies for smoking cessation.

Analysis of comments in a petition defending electronic cigarettes

INTRODUCTION

A 2009 petition opposing a Food and Drug Administration (FDA) ban on electronic cigarettes (e-cigs) garnered international attention from e-cig users (vapers). Petitioners' comments described the perceived benefits of vaping.

METHODS

We conducted a qualitative and quantitative analysis of petitioners' comments. A sample of 200 petitioner names was sought in public records. Reviewers identified 13 major themes in a sample of comments, and themes related to current controversies were added. For each theme, software pattern-matching instructions (regular expressions) were developed and were used to scan comments. Agreement between reviewers and software was calculated; theme prevalence and clustering was ascertained.

RESULTS

A total of 13,414 signatures and 8,285 comments from 50 states and 75 nations were collected in 6 months. Temporal patterns and name matches in public records suggest that most petitioners are authentic. Agreement between reviewers and software was moderate to high (κ = 0.4-0.8). Commonly cited themes were "e-cigs helped me quit" (34%), "a ban would be counterproductive" (15%), and "my health improved with e-cigs" (13%). Two clusters of themes emerged: the first combined comments about smoking cessation, health benefits, and smoking relapse that an e-cig ban would cause; the second combined themes that a "ban would be counterproductive," it would infringe on personal liberties, and it was motivated by government or industrial greed. People who cited mental health issues often mentioned avoiding withdrawal as a benefit of e-cigs.

CONCLUSIONS

Early e-cig adopters were both frustrated and confused by discussion of a ban. They believed that e-cigs safely delivered nicotine and helped them quit smoking.

Electronic cigarette awareness, use history, and expected future use among hospitalized cigarette smokers

INTRODUCTION

E-cigarette use has surged during the past few years while the debate about the product's safety and efficacy for smoking cessation continues. Little is known about the characteristics that distinguish users from nonusers; in this study, we aimed to elucidate these characteristics among hospitalized smokers, a heretofore unstudied population.

METHODS

Cross-sectional data were collected from cigarette smokers via hospital bedside interviews. Participants reported e-cigarette use status, reasons for use (if used), e-cigarette advertising exposure, expected likelihood of future e-cigarette use, desire to quit smoking, and demographic characteristics.

RESULTS

Of the 657 English-speaking hospitalized smokers who provided data, 97% reported awareness of e-cigarettes and 46.4% reported e-cigarette use, with 20% reporting use in the previous 30 days. Previous e-cigarette use was significantly more likely among those who were White (odds ratio [OR] = 4.7; confidence interval [CI] = 3.2-6.7), were married/had a domestic partner (OR = 1.5; CI = 1.0-2.2), had more than a high school education (OR = 1.7; CI = 1.1-2.7), had e-cigarette advertising exposure (OR = 1.6; CI = 1.1-2.4), and were younger (OR = 1.3; CI = 1.1-1.5). Expected likelihood of future e-cigarette use was high and positively correlated with desire to quit smoking (Spearman's ρ = .18, p < .0001).

CONCLUSIONS

Rates of awareness and use of e-cigarettes may be elevated among hospitalized smokers, with more use reported among those who were White, younger, more educated, in a relationship, and exposed to e-cigarette advertising. The association between desire to quit smoking and expected likelihood of future e-cigarette use suggests that cigarette smokers may perceive e-cigarettes as a useful cessation aid.

Levels of saliva cotinine in electronic cigarette users

AIMS

To assess saliva cotinine levels in experienced users of e-cigarettes ('vapers').

DESIGN, SETTING AND PARTICIPANTS

An internet survey in 2011 and 2012, with collection of saliva vials by mail. Participants were 71 users of e-cigarettes enrolled mainly on websites and online forums dedicated to e-cigarettes.

MEASUREMENTS

Use of e-cigarettes, tobacco and nicotine medications. Collection of saliva by mail and analysis of cotinine by liquid chromatography-mass spectrometry.

FINDINGS

Most participants (89%) were former smokers, most (92%) were using e-cigarettes daily, had been using e-cigarettes for 12 months on average and puffed a median of 150 times per day on their e-cigarettes [mean = 220 puffs/day, 95% confidence interval (CI) = 169-271]. The median concentration of nicotine in refill liquids was 16 mg/ml (mean = 16.4, 95% CI = 14.5-18.3). In the 62 e-cigarette users who, in the past 5 days, had not used any tobacco or nicotine medications, the median cotinine level was 353 ng/ml (mean = 374, 95% CI = 318-429), the correlation between cotinine and nicotine concentration in e-liquids was r = 0.33 (P = 0.013), and the correlation between cotinine and the number of cigarettes smoked per day before quitting smoking was r = 0.48 (P < 0.001).

CONCLUSIONS

At least some experienced users of electronic cigarettes appear to be able to gain as much nicotine from those products as do cigarette smokers.

How U.S. adults find out about electronic cigarettes: implications for public health messages

INTRODUCTION

Electronic cigarettes (e-cigarettes) are battery-powered nicotine delivery systems that have become increasingly popular in the United States. We sought to understand how U.S. adults hear about e-cigarettes.

METHODS

A national sample of 17,522 U.S. adults (≥ 18 years old) completed an online survey in March 2013 assessing their awareness of and sources of information about e-cigarettes.

RESULTS

Most respondents (86%) had heard of e-cigarettes. Current and former smokers were more likely to be aware of e-cigarettes than non-smokers. Males, younger adults, non-Hispanic Whites, and those with higher education were also more likely to have heard of e-cigarettes. The most commonly reported sources of information were another person, ads on television, and seeing e-cigarettes being sold, although the relative frequency of these sources differed for current, former, and never-smokers. Former and current smokers were more likely to have heard about e-cigarettes from e-cigarette users than were never-smokers. Adults age 30 years or younger were more likely than adults older than 30 years to have heard about e-cigarettes online.

CONCLUSIONS

Nearly all U.S. adults had heard of e-cigarettes in 2013. By focusing on the most common channels of information, public health campaigns can more efficiently communicate information about e-cigarette safety and consider necessary regulations should companies use these channels for marketing that targets youth, non-tobacco users, and other at-risk groups.

A longitudinal study of electronic cigarette users

OBJECTIVE

To assess behavior change over 12 months in users of e-cigarettes ("vapers").

METHODS

Longitudinal Internet survey, 2011 to 2013. Participants were enrolled on websites dedicated to e-cigarettes and smoking cessation. We assessed use of e-cigarettes and tobacco among the same cohort at baseline, after one month (n=477) and one year (n=367).

RESULTS

Most participants (72%) were former smokers, and 76% were using e-cigarettes daily. At baseline, current users had been using e-cigarettes for 3 months, took 150 puffs/day on their e-cigarette and used refill liquids containing 16 mg/ml of nicotine, on average. Almost all the daily vapers at baseline were still vaping daily after one month (98%) and one year (89%). Of those who had been vaping daily for less than one month at baseline, 93% were still vaping daily after one month, and 81% after one year. In daily vapers, the number of puffs/day on e-cigarettes remained unchanged between baseline and one year. Among former smokers who were vaping daily at baseline, 6% had relapsed to smoking after one month and also 6% after one year. Among dual users (smokers who were vaping daily at baseline), 22% had stopped smoking after one month and 46% after one year. In dual users who were still smoking at follow-up, cigarette consumption decreased by 5.3 cig/day after one month (from 11.3 to 6.0 cig./day, p=0.006), but remained unchanged between baseline and 1-year follow-up.

CONCLUSIONS

E-cigarettes may contribute to relapse prevention in former smokers and smoking cessation in current smokers.

The impact of the 2010 Polish smoke-free legislation on the popularity and sales of electronic cigarettes

Electronic cigarettes, also called e-cigarettes or electronic nicotine delivery systems (ENDS), have become widely available globally, particularly via the Internet. They are considered by many users as a safe alternative to regular cigarettes, and some use them for smoking cessation. We investigated whether the implementation of new tobacco control legislation in Poland affected the popularity and sales of ENDS. This study monitored Google searches and online sales before and after the implementation of new tobacco control legislation in November 2010. The study demonstrated that the implementation of the smoke-free legislation was associated with only a temporary increase in ENDS online popularity in Poland. In longer time frames, there was decrease in ENDS online popularity and sales in Poland after implementation of the smoke-free policy.

Do e-cigarettes have the potential to compete with conventional cigarettes?: a survey of conventional cigarette smokers' experiences with e-cigarettes

BACKGROUND

Electronic cigarettes (ECs) are becoming increasingly popular globally. If they were to replace conventional cigarettes, it could have a substantial impact on public health. To evaluate EC's potential for competing with conventional cigarettes as a consumer product, we report the first data, to our knowledge, on the proportion of smokers who try ECs and become regular users.

METHODS

A total of 2,012 people seen smoking or buying cigarettes in the Czech Republic were approached to answer questions about smoking, with no mention made of ECs to avoid the common bias in surveys of EC users. During the interview, the volunteers' experience with ECs was then discussed.

RESULTS

A total of 1,738 smokers (86%) participated. One-half reported trying ECs at least once. Among those who tried ECs, 18.3% (95% CI, 0.15.7%-20.9%) reported using them regularly, and 14% (95% CI, 11.6%-16.2%) used them daily. On average, regular users used ECs daily for 7.1 months. The most common reason for using ECs was to reduce consumption of conventional cigarettes; 60% of regular EC users reported that ECs helped them to achieve this. Being older and having a more favorable initial experience with ECs explained 19% of the variance in progressing to regular EC use.

CONCLUSIONS

Almost one-fifth of smokers who try ECs once go on to become regular users. ECs may develop into a genuine competitor to conventional cigarettes. Government agencies preparing to regulate ECs need to ensure that such moves do not create a market monopoly for conventional cigarettes.

Acute electronic cigarette use: nicotine delivery and subjective effects in regular users

RATIONALE

Electronic cigarettes are becoming increasingly popular among smokers worldwide. Commonly reported reasons for use include the following: to quit smoking, to avoid relapse, to reduce urge to smoke, or as a perceived lower-risk alternative to smoking. Few studies, however, have explored whether electronic cigarettes (e-cigarettes) deliver measurable levels of nicotine to the blood.

OBJECTIVE

This study aims to explore in experienced users the effect of using an 18-mg/ml nicotine first-generation e-cigarette on blood nicotine, tobacco withdrawal symptoms, and urge to smoke.

METHODS

Fourteen regular e-cigarette users (three females), who are abstinent from smoking and e-cigarette use for 12 h, each completed a 2.5 h testing session. Blood was sampled, and questionnaires were completed (tobacco-related withdrawal symptoms, urge to smoke, positive and negative subjective effects) at four stages: baseline, 10 puffs, 60 min of ad lib use and a 60-min rest period.

RESULTS

Complete sets of blood were obtained from seven participants. Plasma nicotine concentration rose significantly from a mean of 0.74 ng/ml at baseline to 6.77 ng/ml 10 min after 10 puffs, reaching a mean maximum of 13.91 ng/ml by the end of the ad lib puffing period. Tobacco-related withdrawal symptoms and urge to smoke were significantly reduced; direct positive effects were strongly endorsed, and there was very low reporting of adverse effects.

CONCLUSIONS

These findings demonstrate reliable blood nicotine delivery after the acute use of this brand/model of e-cigarette in a sample of regular users. Future studies might usefully quantify nicotine delivery in relation to inhalation technique and the relationship with successful smoking cessation/harm reduction.

Electronic nicotine delivery system (electronic cigarette) awareness, use, reactions and beliefs: a systematic review

OBJECTIVE

We sought to systematically review the literature on electronic nicotine delivery systems (ENDS, also called electronic cigarettes) awareness, use, reactions and beliefs.

DATA SOURCES

We searched five databases for articles published between 2006 and 1 July 2013 that contained variations of the phrases 'electronic cigarette', 'e-cigarette' and 'electronic nicotine delivery'.

STUDY SELECTION

Of the 244 abstracts identified, we excluded articles not published in English, articles unrelated to ENDS, dissertation abstracts and articles without original data on prespecified outcomes.

DATA EXTRACTION

Two reviewers coded each article for ENDS awareness, use, reactions and beliefs.

DATA SYNTHESIS

49 studies met inclusion criteria. ENDS awareness increased from 16% to 58% from 2009 to 2011, and use increased from 1% to 6%. The majority of users were current or former smokers. Many users found ENDS satisfying, and some engaged in dual use of ENDS and other tobacco. No longitudinal studies examined whether ENDS serve as 'gateways' to future tobacco use. Common reasons for using ENDS were quitting smoking and using a product that is healthier than cigarettes. Self-reported survey data and prospective trials suggest that ENDS might help cigarette smokers quit, but no randomised controlled trials with probability samples compared ENDS with other cessation tools. Some individuals used ENDS to avoid smoking restrictions.

CONCLUSIONS

ENDS use is expanding rapidly despite experts' concerns about safety, dual use and possible 'gateway' effects. More research is needed on effective public health messages, perceived health risks, validity of self-reports of smoking cessation and the use of different kinds of ENDS.

Electronic cigarettes and vaping: a new challenge in clinical medicine and public health. A literature review

Electronic cigarette (e-cigarette) use, or vaping, in the United States and worldwide is increasing. Their use is highly controversial from scientific, political, financial, psychological, and sociological ideologies. Given the controversial nature of e-cigarettes and vaping, how should medical care providers advise their patients? To effectively face this new challenge, health care professionals need to become more familiar with the existing literature concerning e-cigarettes and vaping, especially the scientific literature. Thus, the aim of this article is to present a review of the scientific evidence-based primary literature concerning electronic cigarettes and vaping. A search of the most current literature using the pubmed database dating back to 2008, and using electronic cigarette(s) or e-cigarette(s) as key words, yielded a total of 66 highly relevant articles. These articles primarily deal with (1) consumer-based surveys regarding personal views on vaping, (2) chemical analysis of e-cigarette cartridges, solutions, and mist, (3) nicotine content, delivery, and pharmacokinetics, and (4) clinical and physiological studies investigating the effects of acute vaping. When compared to the effects of smoking, the scant available literature suggests that vaping could be a “harm reduction” alternative to smoking and a possible means for smoking cessation, at least to the same degree as other Food and Drug Administration-approved nicotine replacement therapies. However, it is unclear if vaping e-cigarettes will reduce or increase nicotine addiction. It is obvious that more rigorous investigations of the acute and long-term health effects of vaping are required to establish the safety and efficacy of these devices; especially parallel experiments comparing the cardiopulmonary effects of vaping to smoking. Only then will the medical community be able to adequately meet the new challenge e-cigarettes and vaping present to clinical medicine and public health.

The use and perception of electronic cigarettes and snus among the U.S. population

BACKGROUND

E-cigarettes have generated controversy in the tobacco control field similar to that of Swedish snus, which came to the U.S. market six years earlier. Some argue that e-cigarettes have great potential to help smokers quit regular cigarettes while others contend they should be banned for lack of safety and efficacy data. This study examined population data from the U.S.

METHODS

A U.S. population survey with a national probability sample (N=10,041) was conducted (February 24 to March 8, 2012, before any major paid advertisement of e-cigarettes appeared on television). Survey respondents were asked if they had heard about e-cigarettes, where they had heard about them, whether they had used e-cigarettes or snus, how often they used them, and why they used them. Responses were weighted to represent the entire U.S. population.

FINDINGS

A high proportion, 75.4%, reported having heard about e-cigarettes. Television ranked as the number one source of information, followed by "in-person conversation" and "Internet." About 8.1% had tried e-cigarettes, and 1.4% were current users. These rates were twice those of snus (4.3% and 0.8%, respectively). Among current smokers, 32.2% had tried e-cigarettes, and 6.3% were current users. Over 80% of current e-cigarette users were non-daily users. Women were significantly more likely to have tried e-cigarettes than men. Those who had tried e-cigarettes were more likely than those who tried snus to report their products being safer than regular cigarettes (49.9% vs. 10.8%). Almost half (49.5%) of current smokers were susceptible to using e-cigarettes in the future.

CONCLUSIONS

That e-cigarettes have surpassed snus in adoption rate, even before any promotion by major tobacco companies, suggests that the former have tapped into smokers' intuitive preference for potentially harm-reducing products, probably due to the product design. E-cigarette use is likely to increase in the next few years.

A fresh look at tobacco harm reduction: the case for the electronic cigarette

Smokers of any age can reap substantial health benefits by quitting. In fact, no other single public health effort is likely to achieve a benefit comparable to large-scale smoking cessation. Surveys document that most smokers would like to quit, and many have made repeated efforts to do so. However, conventional smoking cessation approaches require nicotine addicted smokers to abstain from tobacco and nicotine entirely. Many smokers are unable – or at least unwilling – to achieve this goal, and so they continue smoking in the face of impending adverse health consequences. In effect, the status quo in smoking cessation presents smokers with just two unpleasant alternatives: quit or suffer the harmful effects of continuing smoking. But, there is a third choice for smokers: tobacco harm reduction. It involves the use of alternative sources of nicotine, including modern smokeless tobacco products like snus and the electronic cigarette (E-cig), or even pharmaceutical nicotine products, as a replacement for smoking. E-cigs might be the most promising product for tobacco harm reduction to date, because, besides delivering nicotine vapour without the combustion products that are responsible for nearly all of smoking’s damaging effect, they also replace some of the rituals associated with smoking behaviour. Thus it is likely that smokers who switch to E-cigs will achieve large health gains. The focus of this article is on the health effects of using an E-cig, with consideration given to the acceptability, safety and effectiveness of this product as a long-term substitute for smoking.

Using twitter to examine smoking behavior and perceptions of emerging tobacco products

BACKGROUND

Social media platforms such as Twitter are rapidly becoming key resources for public health surveillance applications, yet little is known about Twitter users' levels of informedness and sentiment toward tobacco, especially with regard to the emerging tobacco control challenges posed by hookah and electronic cigarettes.

OBJECTIVE

To develop a content and sentiment analysis of tobacco-related Twitter posts and build machine learning classifiers to detect tobacco-relevant posts and sentiment towards tobacco, with a particular focus on new and emerging products like hookah and electronic cigarettes.

METHODS

We collected 7362 tobacco-related Twitter posts at 15-day intervals from December 2011 to July 2012. Each tweet was manually classified using a triaxial scheme, capturing genre, theme, and sentiment. Using the collected data, machine-learning classifiers were trained to detect tobacco-related vs irrelevant tweets as well as positive vs negative sentiment, using Naïve Bayes, k-nearest neighbors, and Support Vector Machine (SVM) algorithms. Finally, phi contingency coefficients were computed between each of the categories to discover emergent patterns.

RESULTS

The most prevalent genres were first- and second-hand experience and opinion, and the most frequent themes were hookah, cessation, and pleasure. Sentiment toward tobacco was overall more positive (1939/4215, 46% of tweets) than negative (1349/4215, 32%) or neutral among tweets mentioning it, even excluding the 9% of tweets categorized as marketing. Three separate metrics converged to support an emergent distinction between, on one hand, hookah and electronic cigarettes corresponding to positive sentiment, and on the other hand, traditional tobacco products and more general references corresponding to negative sentiment. These metrics included correlations between categories in the annotation scheme (phihookah-positive=0.39; phi(e-cigs)-positive=0.19); correlations between search keywords and sentiment (χ²₄=414.50, P<.001, Cramer's V=0.36), and the most discriminating unigram features for positive and negative sentiment ranked by log odds ratio in the machine learning component of the study. In the automated classification tasks, SVMs using a relatively small number of unigram features (500) achieved best performance in discriminating tobacco-related from unrelated tweets (F score=0.85).

CONCLUSIONS

Novel insights available through Twitter for tobacco surveillance are attested through the high prevalence of positive sentiment. This positive sentiment is correlated in complex ways with social image, personal experience, and recently popular products such as hookah and electronic cigarettes. Several apparent perceptual disconnects between these products and their health effects suggest opportunities for tobacco control education. Finally, machine classification of tobacco-related posts shows a promising edge over strictly keyword-based approaches, yielding an improved signal-to-noise ratio in Twitter data and paving the way for automated tobacco surveillance applications.

Electronic cigarette use by college students

BACKGROUND

Electronic cigarettes, or e-cigarettes, are battery operated devices that deliver nicotine via inhaled vapor. There is considerable controversy about the disease risk and toxicity of e-cigarettes and empirical evidence on short- and long-term health effects is minimal. Limited data on e-cigarette use and correlates exist, and to our knowledge, no prevalence rates among U.S. college students have been reported. This study aimed to estimate the prevalence of e-cigarette use and identify correlates of use among a large, multi-institution, random sample of college students.

METHODS

4444 students from 8 colleges in North Carolina completed a Web-based survey in fall 2009.

RESULTS

Ever use of e-cigarettes was reported by 4.9% of students, with 1.5% reporting past month use. Correlates of ever use included male gender, Hispanic or "Other race" (compared to non-Hispanic Whites), Greek affiliation, conventional cigarette smoking and e-cigarette harm perceptions. Although e-cigarette use was more common among conventional cigarette smokers, 12% of ever e-cigarette users had never smoked a conventional cigarette. Among current cigarette smokers, e-cigarette use was negatively associated with lack of knowledge about e-cigarette harm, but was not associated with intentions to quit.

CONCLUSIONS

Although e-cigarette use was more common among conventional cigarette smokers, it was not exclusive to them. E-cigarette use was not associated with intentions to quit smoking among a sub-sample of conventional cigarette smokers. Unlike older, more established cigarette smokers, e-cigarette use by college students does not appear to be motivated by the desire to quit cigarette smoking.

Electronic nicotine delivery systems: international tobacco control four-country survey

BACKGROUND

Electronic nicotine delivery systems (ENDS) initially emerged in 2003 and have since become widely available globally, particularly over the Internet.

PURPOSE

Data on ENDS usage patterns are limited. The current paper examines patterns of ENDS awareness, use, and product-associated beliefs among current and former smokers in four countries.

METHODS

Data come from Wave 8 of the International Tobacco Control Four-Country Survey, collected July 2010 to June 2011 and analyzed through June 2012. Respondents included 5939 current and former smokers in Canada (n=1581); the U.S. (n=1520); the United Kingdom (UK; n=1325); and Australia (n=1513).

RESULTS

Overall, 46.6% were aware of ENDS (U.S.: 73%, UK: 54%, Canada: 40%, Australia: 20%); 7.6% had tried ENDS (16% of those aware of ENDS); and 2.9% were current users (39% of triers). Awareness of ENDS was higher among younger, non-minority smokers with higher incomes who were heavier smokers. Prevalence of trying ENDS was higher among younger, nondaily smokers with a high income and among those who perceived ENDS as less harmful than traditional cigarettes. Current use was higher among both nondaily and heavy (≥20 cigarettes per day) smokers. In all, 79.8% reported using ENDS because they were considered less harmful than traditional cigarettes; 75.4% stated that they used ENDS to help them reduce their smoking; and 85.1% reported using ENDS to help them quit smoking.

CONCLUSIONS

Awareness of ENDS is high, especially in countries where they are legal (i.e., the U.S. and UK). Because trial was associated with nondaily smoking and a desire to quit smoking, ENDS may have the potential to serve as a cessation aid.

Comparison of the effects of e-cigarette vapor and cigarette smoke on indoor air quality

CONTEXT

Electronic cigarettes (e-cigarettes) have earned considerable attention recently as an alternative to smoking tobacco, but uncertainties about their impact on health and indoor air quality have resulted in proposals for bans on indoor e-cigarette use.

OBJECTIVE

To assess potential health impacts relating to the use of e-cigarettes, a series of studies were conducted using e-cigarettes and standard tobacco cigarettes.

METHODS AND MATERIALS

Four different high nicotine e-liquids were vaporized in two sets of experiments by generic 2-piece e-cigarettes to collect emissions and assess indoor air concentrations of common tobacco smoke by products. Tobacco cigarette smoke tests were conducted for comparison.

RESULTS

Comparisons of pollutant concentrations were made between e-cigarette vapor and tobacco smoke samples. Pollutants included VOCs, carbonyls, PAHs, nicotine, TSNAs, and glycols. From these results, risk analyses were conducted based on dilution into a 40 m³ room and standard toxicological data. Non-cancer risk analysis revealed "No Significant Risk" of harm to human health for vapor samples from e-liquids (A-D). In contrast, for tobacco smoke most findings markedly exceeded risk limits indicating a condition of "Significant Risk" of harm to human health. With regard to cancer risk analysis, no vapor sample from e-liquids A-D exceeded the risk limit for either children or adults. The tobacco smoke sample approached the risk limits for adult exposure.

CONCLUSIONS

For all byproducts measured, electronic cigarettes produce very small exposures relative to tobacco cigarettes. The study indicates no apparent risk to human health from e-cigarette emissions based on the compounds analyzed.

Adolescent males' awareness of and willingness to try electronic cigarettes

PURPOSE

Electronic cigarettes (e-cigarettes) are a new type of device that delivers vaporized nicotine without the tobacco combustion of regular cigarettes. We sought to understand awareness of and willingness to try e-cigarettes among adolescent males, a group that is at risk for smoking initiation and may use e-cigarettes as a "gateway" to smoking.

METHODS

A national sample of 11-19-year-old males (n = 228) completed an online survey in November 2011. We recruited participants through their parents, who were members of a panel of U.S. households constructed using random-digit dialing and addressed-based sampling.

RESULTS

Only two participants (< 1%) had previously tried e-cigarettes. Among those who had not tried e-cigarettes, most (67%) had heard of them. Awareness was higher among older and non-Hispanic adolescents. Nearly 1 in 5 (18%) participants were willing to try either a plain or flavored e-cigarette, but willingness to try plain versus flavored varieties did not differ. Smokers were more willing to try any e-cigarette than nonsmokers (74% vs. 13%; OR 10.25, 95% CI 2.88, 36.46). Nonsmokers who had more negative beliefs about the typical smoker were less willing to try e-cigarettes (OR .58, 95% CI .43, .79).

CONCLUSIONS

Most adolescent males were aware of e-cigarettes, and a substantial minority were willing to try them. Given that even experimentation with e-cigarettes could lead to nicotine dependence and subsequent use of other tobacco products, regulatory and behavioral interventions are needed to prevent "gateway" use by adolescent nonsmokers. Campaigns promoting negative images of smokers or FDA bans on sales to youth may help deter use.

Electronic nicotine delivery systems: regulatory and safety challenges: Singapore perspective

OBJECTIVE

Many electronic nicotine delivery systems (ENDS) are marketed as safer tobacco alternative products or effective cessation therapies. ENDS samples were evaluated for design features, including nicotine and glycols content. This could be useful in developing a legal framework to handle ENDS.

METHODS

Identification of the nicotine, glycerol and propylene glycol (PPG) contents was conducted using gas chromatography mass spectrometry with quantification performed using flame ionisation techniques.

RESULTS

Varying nicotine amounts were found in ENDS cartridges which were labelled with the same concentration. Chemicals such as PPG and glycerol were found to be present in the nicotine-containing liquid of the cartridges. ENDS varied in their contents and packaging information. Limited information was available on the contents of nicotine and other chemicals present in a variety of ENDS sampled.

CONCLUSIONS

Based on samples tested in this study, many contain misleading information on product ingredients. The results show poor consistency between actual nicotine content analysed on ENDS cartridges and the amount labelled. These findings raise safety and efficacy concerns for current and would-be recreational users or those trying to quit smoking.

Dependence on tobacco and nicotine products: a case for product-specific assessment

The International Classification of Diseases and the Diagnostic and Statistical Manual for diagnosing tobacco/nicotine dependence emphasize the dependence-producing drug nicotine. These diagnostic tools have been challenged on grounds of poor predictive validity, and they do not differentiate across various forms of nicotine-containing products. In fact, nicotine-containing products (e.g., tobacco cigarettes, smokeless tobacco [ST], waterpipe, electronic cigarettes [ECIGs], and nicotine replacement [NR] products) have very different characteristics both in terms of sensory and behavioral involvement and also in pharmacokinetic and pharmacodynamic effects. For example, a cigarette and a nicotine patch are very different on almost every one of these dimensions. When ability to stop using a nicotine/tobacco product is used as a criterion for dependence, success rates vary considerably across products: Tobacco cigarette cessation is more difficult than ST cessation that in turn is more difficult than NR product cessation. Based on these results, we hypothesize that there is a continuum of dependence as much as there is a continuum of harm, with tobacco cigarettes and NR products on opposite ends of both continua and other products (waterpipe and ECIGs) somewhere in between. In order to capture more precisely the dependence produced by both nicotine and its administration forms, product-specific instruments may be required. The pros and cons of this approach are discussed.

Patterns of electronic cigarette use and user beliefs about their safety and benefits: an internet survey

INTRODUCTION AND AIMS

As the popularity of electronic cigarettes (e-cigarettes) increases, it is becoming important to find out more about the characteristics of e-cigarette users, why and how they use the product and whether e-cigarettes are used exclusively or in combination with conventional cigarettes. The objective of this study was to investigate patterns and effects of e-cigarette use and user beliefs about e-cigarette safety and benefits.

DESIGN AND METHODS

E-cigarette users in Poland were recruited online and asked to participate in a web-based survey. The participants provided information on their smoking history, patterns of e-cigarette use, beliefs and attitudes regarding the product and information on concurrent use of conventional cigarettes.

RESULTS

The survey was completed by 179 e-cigarette users. Almost all participants used e-cigarettes daily. E-cigarettes were primarily used to quit smoking or to reduce the harm associated with smoking (both 41%), and were successful in helping the surveyed users to achieve these goals with 66% not smoking conventional cigarettes at all and 25% smoking under five cigarettes a day. Most participants (82%) did not think that e-cigarettes were completely safe, but thought that they were less dangerous than conventional cigarettes. Sixty percent believed that e-cigarettes were addictive, but less so than conventional cigarettes.

DISCUSSION AND CONCLUSIONS

The participants primarily used e-cigarettes as a stop-smoking aid or as an alternative to conventional cigarettes, and the majority reported that they successfully stopped smoking. More data on e-cigarette safety and its efficacy in harm-reduction and smoking cessation are needed.

Clinical laboratory assessment of the abuse liability of an electronic cigarette

AIMS

  To provide an initial abuse liability assessment of an electronic cigarette (EC) in current tobacco cigarette smokers.

DESIGN

  The first of four within-subject sessions was an EC sampling session that involved six, 10-puff bouts (30 seconds inter-puff interval), each bout separated by 30 minutes. In the remaining three sessions participants made choices between 10 EC puffs and varying amounts of money, 10 EC puffs and a varying number of own brand cigarette (OB) puffs, or 10 OB puffs and varying amounts of money using the multiple-choice procedure (MCP). The MCP was completed six times at 30-minute intervals, and one choice was reinforced randomly at each trial.

SETTING

  Clinical laboratory.

PARTICIPANTS

  Twenty current tobacco cigarette smokers.

MEASUREMENTS

  Sampling session outcome measures included plasma nicotine, cardiovascular response and subjective effects. Choice session outcome was the cross-over value on the MCP.

FINDINGS

  EC use resulted in significant nicotine delivery, tobacco abstinence symptom suppression and increased product acceptability ratings. On the MCP, participants chose to receive 10 EC puffs over an average of $1.06 or three OB puffs and chose 10 OB puffs over an average of $1.50 (P < 0.003).

CONCLUSIONS

  Electronic cigarettes can deliver clinically significant amounts of nicotine and reduce cigarette abstinence symptoms and appear to have lower potential for abuse relative to traditional tobacco cigarettes, at least under certain laboratory conditions.

Electronic cigarettes: do they have a role in smoking cessation?

Electronic cigarettes have gained popularity among patients as a smoking cessation aid despite not being approved or supported for this purpose by the United States Food and Drug Administration due to concerns with poor manufacturing practices and the presence of known carcinogens in the limited products that they tested. A few studies have evaluated the effects of electronic cigarettes on plasma nicotine levels and heart rate but found negligible effects. Safety data are mainly limited to surveys in which patients report only minor side effects, such as mouth and throat irritation, headache, vertigo, and nausea. The efficacy of electronic cigarettes has been evaluated in studies in which patients report great success with being able to cut back or stop tobacco cigarette consumption. However, many of these studies introduce bias due to recruiting on e-cigarette Web sites and having tobacco cigarette use self-reported by the participant rather than objectively tested. A few studies have formally evaluated nicotine craving when using electronic cigarettes with mixed results. Although patients support the use of electronic cigarettes in smoking cessation, more formal studies on safety and efficacy should be completed in order to determine whether these products have a role in smoking cessation.

Electronic cigarettes: effective nicotine delivery after acute administration

INTRODUCTION

Electronic cigarettes (ECs) are marketed as nicotine delivery devices. Two studies with EC-naïve participants suggest that ECs deliver little or no nicotine. In those studies, standard-sized ECs were used, though experienced EC users often use larger devices that house higher voltage and/or longer lasting batteries. Whether user experience and device characteristics influence EC nicotine delivery is uncertain. The purpose of the present study was to examine the effects of ECs in experienced users who were using their preferred devices.

METHODS

Eight EC users (3 women) who had been using ECs for at least 3 months, completed one 5-hr session using devices they provided and the flavor/strength nicotine cartridges they selected. Sessions consisted of 4 phases: baseline, 10 puffs (30-s interpuff interval) from the device, 1-hr ad lib puffing period, and a 2-hr rest period (no puffing). Outcome measures in each phase included plasma nicotine concentration, heart rate, and subjective ratings of nicotine/product effects and abstinence symptoms.

RESULTS

Relative to baseline, plasma nicotine and heart rate increased significantly within 5 min of the first puff and remained elevated throughout the ad lib puffing period. Increases in ratings of direct effects of nicotine and product were observed as well as decreases in abstinence symptoms.

CONCLUSIONS

User experience and/or device characteristics likely influence EC nicotine delivery and other effects. Systematic manipulation of these and other variables could elucidate conditions that produce intended effects.