Search

Electronic nicotine delivery systems (ENDS) continue to rapidly evolve. Current products pose unique challenges and opportunities for researchers and regulators. This commentary aims to highlight research gaps, particularly in toxicity research, and provide guidance on priority research questions for the tobacco regulatory community. Disposable flavoured ENDS have become the most popular device class among youth and may contain higher nicotine levels than JUUL devices. They also exhibit enhanced harmful and potentially harmful constituents production, contain elevated levels of synthetic coolants and pose environmental concerns. Synthetic nicotine and flavour capsules are innovations that have recently enabled the circumvention of Food and Drug Administration oversight. Coil-less ENDS offer the promise of delivering fewer toxicants due to the absence of heating coils, but initial studies show that these products exhibit similar toxicological profiles compared with JUULs. Each of these topic areas requires further research to understand and mitigate their impact on human health, especially their risks to young users.

ObjectiveTo assess the effectiveness of e-cigarettes in smoking cessation in the USA from 2017 to 2019, given the 2017 increase in high nicotine e-cigarette sales.MethodsIn 2017, the PATH Cohort Study included data on 3578 previous year smokers with a recent quit attempt and 1323 recent former smokers. Respondents reported e-cigarettes or other products used to quit cigarettes and many covariates associated with e-cigarette use. Study outcomes were 12+ months of cigarette abstinence and tobacco abstinence in 2019. We report weighted unadjusted estimates and use propensity score matched analyses with 1500 bootstrap samples to estimate adjusted risk differences (aRD).ResultsIn 2017, 12.6% (95% CI 11.3% to 13.9%) of recent quit attempters used e-cigarettes to help with their quit attempt, a decline from previous years. Cigarette abstinence for e-cigarette users (9.9%, 95% CI 6.6% to 13.2%) was lower than for no product use (18.6%, 95% CI 16.0% to 21.2%), and the aRD for e-cigarettes versus pharmaceutical aids was -7.3% (95% CI -14.4 to -0.4) and for e-cigarettes versus any other method was -7.7% (95% CI -12.2 to -3.2). Only 2.2% (95% CI 0.0% to 4.4%) of recent former smokers switched to a high nicotine e-cigarette. Subjects who switched to e-cigarettes appeared to have a higher relapse rate than those who did not switch to e-cigarettes or other tobacco, although the difference was not statistically significant.ConclusionsSales increases in high nicotine e-cigarettes in 2017 did not translate to more smokers using these e-cigarettes to quit smoking. On average, using e-cigarettes for cessation in 2017 did not improve successful quitting or prevent relapse.

BackgroundThe increased popularity of electronic cigarettes (e-cigarettes) has been linked to the abundance of flavoured products that are attractive to adolescents and young adults. In the last decade, e-cigarette designs have evolved through four generations that include modifications in battery power, e-cigarette liquid (e-liquid) reservoirs and atomiser units. E-liquids have likewise evolved in terms of solvent use/ratios, concentration and number of flavour chemicals, use of nicotine salts and acids, the recent increased use of synthetic cooling agents and the introduction of synthetic nicotine. Our current objective was to evaluate and compare the evolving composition of tobacco-flavoured e-liquids over the last 10 years.MethodsOur extensive database of flavour chemicals in e-liquids was used to identify trends and changes in flavour chemical composition and concentrations.ResultsTobacco-flavoured products purchased in 2010 and 2011 generally had very few flavour chemicals, and their concentrations were generally very low. In tobacco-flavoured refill fluids purchased in 2019 and Puff Bar Tobacco e-cigarettes, the total number and concentration of flavour chemicals were higher than expected. Products with total flavour chemicals >10 mg/mL contained one to five dominant flavour chemicals (>1 mg/mL). The most frequently used flavour chemicals in tobacco e-liquids were fruity and caramellic.ConclusionsThere is a need for continuous surveillance of e-liquids, which are evolving in often subtle and harmful ways. Chemical constituents of tobacco flavours should be monitored as they clearly can be doctored by manufacturers to have a taste that would appeal to young users.

With patented nicotine salt technology, JUUL dominates the e-cigarette market. We reviewed studies of JUUL's nicotine pharmacokinetic profile and studies quantifying nicotine in a JUULpod, emitted in the aerosol and absorbed by users. Examined in eight studies, JUUL's peak nicotine levels were half to three-quarters that of a combustible cigarette in industry-conducted studies with JUUL-naïve users, while comparable to or greater than combustible cigarettes in independent studies of experienced e-cigarette users. JUUL Labs reports each 5% (nicotine-by-weight) cartridge contains approximately 40 mg nicotine per pod and is 'approximately equivalent to about 1 pack of cigarettes.' In five independent studies, nicotine in the liquid in a JUULpod ranged from 39.3 to 48.3 mg. Seven studies measured nicotine delivery via vaping-machine generated aerosols, varying in puffing regimes and equipment. One study estimated 68% transfer efficiency to the aerosol, measuring 28.8 mg nicotine per JUULpod. The other studies reported nicotine values ranging from 72 to 164 µg/puff. At 200 puffs, this is 14.4-32.8 mg of nicotine per pod with equivalence to 13-30 cigarettes. A study measuring nicotine levels in JUUL users during a 5-day controlled switch found equivalence to 18 cigarettes. One JUULpod appears capable of delivering the nicotine equivalent to smoking about a pack of cigarettes, with variability. In JUUL-naïve smokers, JUUL's nicotine boost was lower than that of combustible cigarettes; while in experienced users, JUUL was comparable. Minimising harshness and adaptive to user experience, JUUL's design facilitates initiation to a high nicotine, and ultimately, highly addictive vaping product.

BackgroundHeated tobacco products (HTP) generate nicotine-containing aerosol by heating tobacco rather than burning it. The US Food and Drug Administration (FDA) has recently authorised the sale of one HTP brand, iQOS, in the USA. This study examined the awareness, use and risk perceptions of HTP in the USA following FDA authorisation.MethodsA national probability sample of 20 449 US adults completed an online survey between November 2019 and February 2020. In addition to assessing awareness and use of HTP, two ratios were calculated: the ratio of those who experimented with HTP given that they had heard about it (E/H) and the ratio of those who currently used HTP given experimentation (C/E). These ratios for HTP were compared against those for e-cigarettes from a similar national survey in 2012.ResultsOverall, 8.1% of respondents had heard of HTP. Only 0.55% had tried and 0.10% were current users. The rate of experimentation among those who heard about HTP and the rate of current use among experimenters were, however, similar to those for e-cigarettes in 2012: E/H and C/E for HTP were 6.8% and 18.2%, respectively; and 10.7% and 17.8%, respectively for e-cigarettes. The majority of respondents considered HTP either less harmful than (11.6%), or equally harmful as e-cigarettes (42.7%).ConclusionsOnly a small fraction of US population in 2020 have tried any HTP. However, the similarity in early adoption rates following awareness, suggests that future adoption for HTP may be similar to that for e-cigarettes, if HTP are marketed more aggressively.

BackgroundThis study analysed posts to Instagram related to KandyPens, an open-system pod mod e-cigarette company, marketing its products as aromatherapy devices. The objective was to determine themes, corresponding user profiles and references to types of e-liquid solutions used with KandyPens.MethodsData consisted of publicly available posts to Instagram with the hashtag '#kandypens' collected from 8 June to 8 August 2018 (n=1775). Identified themes included: product appearance (eg, highlighting design features including colour of device), user experience (eg, vape tricks), flavours (eg, strawberry) and promotions (eg, $10 off). The type of e-liquid solutions (nicotine, aromatherapy and cannabis) used with KandyPens were also recorded. Instagram profiles were categorised into: vaping enthusiast/advocates, influencers, KandyPens' official Instagram account, vape vendors and average Instagram users.ResultsUser experience (28.90%) and product appearance (21.80%) were predominant themes followed by promotions (10.08%), and flavours (1.01%). About 32.43 % of posts referenced cannabis-related solutions, 2.98 % of the posts mentioned nicotine-related solutions and 0.11 % of the posts mentioned aromatherapy. Average Instagram users (24.89%) posted the majority of posts followed by vape vendors (20.72%), KandyPens' official account (17.96%), vaping enthusiasts/advocates (10.75%) and influencers (0.45%).ConclusionKandyPens markets its products as aromatherapy devices; however, Instagram posts related to these products rarely mentioned their purported purpose. Future research should consider product design, user experience and the co-use of nicotine and cannabis with KandyPens to assess implications related to product appeal and abuse liability.

BackgroundPrevious secondhand smoke (SHS) reduction interventions have provided only delayed feedback on reported smoking behaviour, such as coaching, or presenting results from child cotinine assays or air particle counters.DesignThis SHS reduction trial assigned families at random to brief coaching and continuous real-time feedback (intervention) or measurement-only (control) groups.ParticipantsWe enrolled 298 families with a resident tobacco smoker and a child under age 14.InterventionWe installed air particle monitors in all homes. For the intervention homes, immediate light and sound feedback was contingent on elevated indoor particle levels, and up to four coaching sessions used prompts and praise contingent on smoking outdoors. Mean intervention duration was 64 days.MeasuresThe primary outcome was 'particle events' (PEs) which were patterns of air particle concentrations indicative of the occurrence of particle-generating behaviours such as smoking cigarettes or burning candles. Other measures included indoor air nicotine concentrations and participant reports of particle-generating behaviour.ResultsPEs were significantly correlated with air nicotine levels (r=0.60) and reported indoor cigarette smoking (r=0.51). Interrupted time-series analyses showed an immediate intervention effect, with reduced PEs the day following intervention initiation. The trajectory of daily PEs over the intervention period declined significantly faster in intervention homes than in control homes. Pretest to post-test, air nicotine levels, cigarette smoking and e-cigarette use decreased more in intervention homes than in control homes.ConclusionsResults suggest that real-time particle feedback and coaching contingencies reduced PEs generated by cigarette smoking and other sources.Trial registration numberNCT01634334; Post-results.

BackgroundThe risks of polytobacco use among young adults are unclear because we know relatively little about the consistency of multiproduct patterns over time and how these patterns impact cigarette smoking. The purpose of this study was to examine changes in multiple tobacco product use over time and associations with cigarette smoking quantity.MethodsParticipants (n=335; 55% male) were 18-24 years old non-daily cigarette smokers living in California. Polytobacco use patterns were assessed quarterly for 2 years.ResultsTransition analyses showed that while the number of products that had been used recently was volatile, the most common pattern was stability between timepoints. A longitudinal negative binomial regression model indicated that those who used more non-cigarette products also reported greater cigarette quantity. The strength of this relationship increased over time.ConclusionsFindings suggest that individuals who use more tobacco products are at greater risk for increased cigarette smoking and maintaining a multiple product use pattern.

BackgroundElectronic cigarettes (ECs) are nicotine delivery devices that produce aerosol without combustion of tobacco; therefore, they do not produce sidestream smoke. Nevertheless, many users exhale large clouds of aerosol that can result in passive exposure of non-users. Analogous to thirdhand cigarette smoke, the exhaled aerosol also settles on indoor surfaces where it can produce a residue. We refer to this residue as EC exhaled aerosol residue (ECEAR). Our objective was to determine if exhaled EC aerosol transferred from a vape shop in a multiple-tenant retail building, where it was produced, to a nearby business (field site) where it could deposit as ECEAR.MethodsWe examined the build-up of ECEAR in commonly used materials (cotton towel and paper towels) placed inside the field site across from the vape shop. Materials were subjected to short-term (days) and long-term (months) exposures. Nicotine, other alkaloids and tobacco-specific nitrosamines (TSNAs) were identified and quantified in controls and field site samples using analytical chemical techniques.ResultsNicotine and other alkaloids were detected after 1 day of exposure in the field site, and these chemicals generally increased as exposure times increased. TSNAs, which have been linked to carcinogenesis, were also detected in short-term and long-term exposed samples from the field site.ConclusionsIn a multiple-tenant retail building, chemicals in EC aerosol travelled from a vape shop into an adjacent business where they deposited forming ECEAR. Regulatory agencies and tenants occupying such buildings should be aware of this potential environmental hazard.

BackgroundIn response to a changing regulatory and consumer landscape, tobacco companies developed new strategies to promote cigarettes and smoking. We examined one of these strategies: to fund and conduct scientific research related to potential benefits of nicotine, and to use their findings to promote nicotine.MethodsQualitative analysis of previously secret tobacco industry documents from the Truth (formerly Legacy) Tobacco Documents Library (industrydocuments.library.ucsf.edu/tobacco), triangulated with data from other sources, including the online search engine Google, from the 1970s to December 2017.ResultsAfter publication of the 1988 Surgeon General's report on nicotine addiction, tobacco companies (particularly RJ Reynolds) intensified efforts to promote the benefits of nicotine while downplaying its addictiveness and health risks. Activities included building relationships with academic institutions and funding scientific studies of the benefits of nicotine on cognition and other performance areas through intramural and extramural programmes. Companies then promoted their research findings through public relations campaigns, often minimising nicotine's health risks by comparing it to caffeine or coffee. These comparisons appeared in highly publicised scientific meetings and interviews with the press. Nicotine-positive messages reappeared in the popular press and on some company websites in the 2010s.ConclusionsTobacco companies implemented strategies to promote benefits of nicotine to scientific and general audiences while minimising its health risks. These strategies reappeared at the time novel tobacco products like electronic cigarettes were introduced. A greater awareness of the source of claims related to purported benefits of nicotine could inform discussions about emerging tobacco products.

OBJECTIVE:To evaluate performance of the I quit original smoking (iQOS) heat-not-burn system as a function of cleaning and puffing topography, investigate the validity of manufacturer's claims that this device does not burn tobacco and determine if the polymer-film filter is potentially harmful. METHODS:iQOS performance was evaluated using five running conditions incorporating two different cleaning protocols. Heatsticks were visually and stereomicroscopically inspected preuse and postuse to determine the extent of tobacco plug charring (from pyrolysis) and polymer-film filter melting, and to elucidate the effects of cleaning on charring. Gas chromatography-mass spectrometry headspace analysis was conducted on unused polymer-film filters to determine if potentially toxic chemicals are emitted from the filter during heating. RESULTS:For all testing protocols, pressure drop decreased as puff number increased. Changes in testing protocols did not affect aerosol density. Charring due to pyrolysis (a form of organic matter thermochemical decomposition) was observed in the tobacco plug after use. When the manufacturer's cleaning instructions were followed, both charring of the tobacco plug and melting of the polymer-film filter increased. Headspace analysis of the polymer-film filter revealed the release of formaldehyde cyanohydrin at 90°C, which is well below the maximum temperature reached during normal usage. DISCUSSION:Device usage limitations may contribute to decreases in interpuff intervals, potentially increasing user's intake of nicotine and other harmful chemicals. This study found that the tobacco plug does char and that charring increases when the device is not cleaned between heatsticks. Release of formaldehyde cyanohydrin is a concern as it is highly toxic at very low concentrations.

BackgroundHeated tobacco products (also called 'heat-not-burn' products) heat tobacco at temperatures below that of combustion, causing nicotine and other compounds to aerosolise. One such product, IQOS from Philip Morris International, is being marketed internationally with claims of harm reduction. We sought to determine whether exposure to IQOS aerosol impairs arterial flow-mediated dilation (FMD), a measure of vascular endothelial function that is impaired by tobacco smoke.MethodsWe exposed anaesthetised rats (n=8/group) via nose cone to IQOS aerosol from single HeatSticks, mainstream smoke from single Marlboro Red cigarettes or clean air for a series of consecutive 30 s cycles over 1.5-5 min. Each cycle consisted of 15 or 5 s of exposure followed by removal from the nose cone. We measured pre-exposure and postexposure FMD, and postexposure serum nicotine and cotinine.ResultsFMD was impaired comparably by ten 15 s exposures and ten 5 s exposures to IQOS aerosol and to cigarette smoke, but not by clean air. Serum nicotine levels were similar to plasma levels after humans have smoked one cigarette, confirming that exposure conditions had real-world relevance. Postexposure nicotine levels were ~4.5-fold higher in rats exposed to IQOS than to cigarettes, despite nicotine being measured in the IQOS aerosol at ~63% the amount measured in smoke. When IQOS exposure was briefer, leading to comparable serum nicotine levels to the cigarette group, FMD was still comparably impaired.ConclusionsAcute exposures to IQOS aerosol impairs FMD in rats. IQOS use does not necessarily avoid the adverse cardiovascular effects of smoking cigarettes.

BackgroundSecondhand smoke (SHS) in US casinos is common, but little is known about the residue of tobacco smoke pollutants left behind in dust and on surfaces, commonly referred to as thirdhand smoke (THS). We examined SHS and THS pollution and exposure before and during a casino smoking ban and after smoking resumed.MethodsA casino was visited nine times over a 15-month period to collect dust, surface and air samples in eight locations. Finger wipe and urine samples were collected from non-smoking confederates before and after a 4-hour casino visit. Samples were analysed for markers of SHS and THS pollution and exposure.ResultsExceptionally high levels of THS were found in dust and on surfaces. Although the smoking ban led to immediate improvements in air quality, surface nicotine levels were unchanged and remained very high for the first month of the smoking ban. Surface nicotine decreased by 90% after 1 month (P