Risk versus regulation: an update on the state of e-cigarette control in Australia.

E-cigarettes are increasingly common around the world, particularly among youth. Ingestion of nicotine-containing e-liquid, while relatively rare, is the major toxicological risk associated with their use. Current Australian regulation has nicotine for use in e-cigarettes listed as a dangerous poison in Schedule 7, with its supply or sale illegal in all states and territories, while regulation on the sale of e-cigarettes and accessories varies by state. However, with increasing evidence that e-cigarettes produce far fewer toxic by-products than their combustible counterparts perhaps it is time to review this regulation.

Are electronic cigarettes a healthier alternative to conventional tobacco smoking?

Electronic cigarettes (EC) with and without nicotine are used by more and more consumers within the last decade. The long-term risks of vapor inhalation are unknown. This study should describe the state of the art of knowledge with respect to the following four items: (1) ingredients of the vapor and their potential risks, the influence of EC on smoking of combustible tobacco to (2) adults and (3) the youth, and (4) the side effects of passive vaping. The vapor of EC contains, in comparison to tobacco smoke, less harmful substances, qualitatively and quantitatively. But, due to failing standardization of EC, this comparison is difficult. Adults are often using both, EC and combustible cigarettes dually. In addition, EC were used for supporting smoke-quitting. Unfortunately, consuming EC with and without nicotine due later to a higher risk of conventional tobacco smoking for the user. In general, the effects of passive vaporing are unknown. Although the vapor of EC is less harmful than tobacco smoke, EC are not hazard-free lifestyle products. Technical standardization should be desirable. Adult smoker's benefit using EC is given by completely change to EC only. The rates of success using EC for smoke quitting are not well evaluated. Children and their parents should be informed on the risks of EC use as a precursor of combustible smoking mandatorily. Internet selling EC to any non-adult should be forbidden by law. EC ought not to be allowed to weaken non-smoker's rights, and third persons should be protected by the potential hazards of EC vaporing.

Evaluation of E-Vapor Nicotine and Nicotyrine Concentrations under Various E-Liquid Compositions, Device Settings, and Vaping Topographies.

Nicotine is one of the major components of electronic cigarette (e-cigarette) emissions. Nicotyrine is a product of nicotine dehydrogenation in e-vapor and is a known inhibitor of human cytochrome P450 enzyme, which mediates nicotine metabolism. However, the emission of nicotine and especially nicotyrine from e-cigarettes has not been studied under real-world vaping patterns. This study examined the impact of e-liquid composition, e-cigarette device power output, and vaping topography on nicotine and nicotyrine concentrations under real-world vaping patterns. The amount of nicotine emitted from e-cigarettes vaped at high e-liquid nicotine levels, high device power, and large puff volumes ranged from 0.365 µg/puff to 236 µg/puff and was comparable to the amount of nicotine emitted from regular cigarettes. E-cigarette coil temperatures (200-300 °C) favored the formation of nicotyrine: E-cigarette vaping generated 2- to 63-fold more nicotyrine per unit nicotine emission than conventional cigarette smoking. High nicotyrine emission from e-cigarettes indicates that nicotine metabolism could be potentially interrupted, which could lead to reduced e-cigarette usage, and result in lower exposures to toxic chemicals (e.g., formaldehyde and acetaldehyde). However, higher serum nicotine levels might increase cancer risks by stimulating nicotinic acetylcholine receptors (nAchRs).

Nicotine and Carbonyl Emissions From Popular Electronic Cigarette Products: Correlation to Liquid Composition and Design Characteristics.

Introduction: Available in hundreds of device designs and thousands of flavors, electronic cigarette (ECIG) may have differing toxicant emission characteristics. This study assesses nicotine and carbonyl yields in the most popular brands in the U.S. market. These products included disposable, prefilled cartridge, and tank-based ECIGs. Methods: Twenty-seven ECIG products of 10 brands were procured and their power outputs were measured. The e-liquids were characterized for pH, nicotine concentration, propylene glycol/vegetable glycerin (PG/VG) ratio, and water content. Aerosols were generated using a puffing machine and nicotine and carbonyls were, respectively, quantified using gas chromatograph and high-performance liquid chromatography. A multiregression model was used to interpret the data. Results: Nicotine yields varied from 0.27 to 2.91 mg/15 puffs, a range corresponding to the nicotine yield of less than 1 to more than 3 combustible cigarettes. Nicotine yield was highly correlated with ECIG type and brand, liquid nicotine concentration, and PG/VG ratio, and to a lower significance with electrical power, but not with pH and water content. Carbonyls, including the carcinogen formaldehyde, were detected in all ECIG aerosols, with total carbonyl concentrations ranging from 3.72 to 48.85 µg/15 puffs. Unlike nicotine, carbonyl concentrations were mainly correlated with power. Conclusion: In 15 puffs, some ECIG devices emit nicotine quantities that exceed those of tobacco cigarettes. Nicotine emissions vary widely across products but carbonyl emissions showed little variations. In spite of that ECIG users are exposed to toxicologically significant levels of carbonyl compounds, especially formaldehyde. Regression analysis showed the importance of design and e-liquid characteristics as determinants of nicotine and carbonyl emissions. Implications: Periodic surveying of characteristics of ECIG products available in the marketplace is valuable for understanding population-wide changes in ECIG use patterns over time.

Nicotine Delivery to the Aerosol of a Heat-Not-Burn Tobacco Product: Comparison With a Tobacco Cigarette and E-Cigarettes.

Introduction: The purpose was to measure nicotine levels to the tobacco and levels emitted to the aerosol of a heat-not-burn product (HnB, IQOS) compared to e-cigarettes (ECs) and a tobacco cigarette. Methods: The HnB device and regular and menthol sticks were purchased from Italy. Three types of ECs (ciga-like, eGo-style, and variable wattage) and a commercially-available tobacco cigarette were also tested. A custom-made liquid containing 2% nicotine was used with ECs. Products were tested using Health Canada Intense puffing regime while HnB and ECs were additionally tested using a 4-second puff duration regime while maintaining the same puff volume. Results: Nicotine content in HnB regular and menthol tobacco sticks was 15.2 ± 1.1 mg/g and 15.6 ± 1.7 mg/g tobacco respectively. The levels of nicotine to the aerosol were similar for regular and menthol HnB products (1.40 ± 0.16 and 1.38 ± 0.11 mg/12 puffs respectively) and did not change significantly with prolonged puff duration. The tobacco cigarette delivered the highest level of nicotine (1.99 ± 0.20 mg/cigarette), with levels being higher than HnB and ECs under Health Canada Intense regime but similar to eGo-style and variable wattage ECs at prolonged puff duration regime. Conclusions: The HnB product delivers nicotine to the aerosol at levels higher than ECs but lower than a tobacco cigarette when tested using Health Canada Intense puffing regime. No change in HnB nicotine delivery was observed at prolonged puff duration with the same puff volume, unlike ECs which deliver more nicotine with longer puff duration. Implications: Nicotine delivery to the smoker is expected to play an important role in the ability of any harm-reduction product to successfully substitute smoking. This study evaluated the content and nicotine delivery to the aerosol of a heat-not-burn tobacco product (IQOS) in comparison with e-cigarettes and a tobacco cigarette. The main findings were that the heat-not-burn tobacco sticks contained similar nicotine concentration to tobacco cigarettes, and that the levels of nicotine delivered to the aerosol of the heat-not-burn products were lower than tobacco cigarette, higher than e-cigarettes at low puff duration but lower than high-power e-cigarettes at longer puff duration.

Changes in Puffing Topography and Nicotine Consumption Depending on the Power Setting of Electronic Cigarettes.

Introduction: The study purpose was to evaluate changes in puffing topography of experienced electronic cigarette users (vapers) when changing power settings in electronic cigarette battery devices. Methods: Experienced adult vapers (n = 21) were recruited. Participants used their own liquids and an atomizer and battery provided by the researchers. Two 30-minute sessions were performed, with the device power set at 6 W and 10 W, in a randomized, crossover, participant-blinded design. Puff number and duration (mean [SD]) were recorded in the provided electronic cigarette battery device, whereas the atomizers were weighted before and after use to determine liquid and nicotine consumption. Results: Puff number and puff duration were lower at 10 W (46 [16] puffs and 3.8 [0.8] s) compared with 6 W (57 [20] puffs and 4.6 [1.0] s). Liquid and nicotine consumption was higher at 10 W (373 [176] mg and 4.2 [2.4] mg, respectively) compared with 6 W (308 [165] mg and 3.5 [2.3] mg, respectively). Vapers reported more aerosol volume and ease of use at 10 W compared with 6 W. Conclusions: The study identified an attempt for compensatory puffing patterns and nicotine self-titration, with a change in puffing patterns (puff number and duration) observed when changing the power settings of an e-cigarette device. Implications: Compensatory smoking behavior and nicotine self-titration is a well-established phenomenon. In electronic cigarettes, changing nicotine concentration in the liquid has been shown to trigger a compensatory puffing pattern. Herein, power setting of the electronic cigarette device was found to be a parameter associated with changes in puffing behavior, whereas higher power was preferable for the participants. These findings could contribute to the understanding of patterns of electronic cigarette use and could explain the preference of dedicated vapers to higher power devices. Additionally, laboratory studies evaluating aerosol emissions should consider using different puffing patterns according to the power settings tested.

Compensatory Puffing With Lower Nicotine Concentration E-liquids Increases Carbonyl Exposure in E-cigarette Aerosols.

Introduction: Article 20 of the European Tobacco Products Directive (EU-TPD) specifies that e-liquids should not contain nicotine in excess of 20 mg/mL, thus many vapers may be compelled to switch to lower concentrations and in so doing, may engage in more intensive puffing. This study aimed to establish whether more intensive puffing produces higher levels of carbonyl compounds in e-cigarette aerosols. Methods: Using the HPLC-UV diode array method, four carbonyl compounds (formaldehyde, acetaldehyde, acetone, and acrolein) were measured in liquids and aerosols from nicotine solutions of 24 and 6 mg/mL. Aerosols were generated using a smoking machine configured to replicate puffing topography data previously obtained from 12 experienced e-cigarette users. Results: Carbonyl levels in aerosols from the puffing regimen of 6 mg/mL were significantly higher (p < .05 using independent samples t tests) compared with those of 24 mg/mL nicotine. For the 6 and 24 mg/mL nicotine aerosols respectively, means ± SD for formaldehyde levels were 3.41 ± 0.94, and 1.49 ± 0.30 µg per hour (µg/h) of e-cigarette use. Means ± SD for acetaldehyde levels were 2.17 ± 0.36 and 1.04 ± 0.13 µg/h. Means ± SD for acetone levels were 0.73 ± 0.20 and 0.28 ± 0.14 µg/h. Acrolein was not detected. Conclusions: Higher levels of carbonyls associated with more intensive puffing suggest that vapers switching to lower nicotine concentrations (either due to the EU-TPD implementation or personal choice), may increase their exposure to these compounds. Based on real human puffing topography data, this study suggests that limiting nicotine concentrations to 20 mg/mL may not result in the desired harm minimalization effect. Implications: More intensive puffing regimens associated with the use of low nicotine concentration e-liquids can lead to higher levels of carbonyl generation in the aerosol. Although in need of replication in a larger sample outside a laboratory, this study provides pragmatic empirical data on the potential risks of compensatory puffing behaviors in vapers, and can help to inform future regulatory decisions on nicotine e-liquid concentrations. The cap on nicotine concentration at 20 mg/mL set by the EU-TPD may therefore have the unintended consequence of encouraging use of lower nicotine concentration e-liquid, in turn increasing exposure to carbonyl compounds through compensatory puffing.

The impact of flavour, device type and warning messages on youth preferences for electronic nicotine delivery systems: evidence from an online discrete choice experiment.

OBJECTIVE: To examine the impact of flavour, device type and health warning messages on youth preference for electronic nicotine delivery systems (ENDS), and to provide evidence and data to inform the Food and Drug Administration's potential regulatory actions on ENDS. DESIGN: An online discrete choice experiment was conducted in September 2015. Each participant was given nine choice sets and asked to choose one out of two alternative ENDS products, with varying characteristics in three attributes (flavour, device type and warning message). The impact of the attributes on the probability of choosing ENDS was analysed using conditional and nested logit regressions, controlling for individual sociodemographic characteristics and current smoking status. SETTING AND PARTICIPANTS: A general population sample of 515 participants (50 ever-users and 465 never-users of ENDS) aged 14-17 years were recruited to complete the experiment using an online panel. RESULTS: Fruit/sweets/beverage flavours significantly increase the probability of choosing ENDS among youth (p<0.01 for never-users and <0.1 for ever-users) and flavour has the most pronounced impact among three attributes. Among never-users, menthol flavour also increases (p<0.05) the probability of choosing ENDS compared with tobacco flavour. Vaping devices that are modifiable, compared with cigarette-like e-cigarettes, increase (p<0.05) the probability of choosing ENDS among adolescent never-users. Warning messages reduce (p<0.01) the probability of choosing ENDS among never-users. CONCLUSIONS AND RELEVANCE: Restricting fruit/sweets/beverage flavours in ENDS, regulating modifiable vaping devices and adopting strong health warning messages may reduce the uptake of ENDS among youth.

Short-term respiratory effects of e-cigarettes in healthy individuals and smokers with asthma.

BACKGROUND AND OBJECTIVE: This study investigated the duration of immediate respiratory effects of e-cigarette smoking (ECS) and tested the hypothesis that ECS has more prominent effects in asthmatics compared with healthy smokers (HS). METHODS: Fifty-four smokers, 27 healthy (HS group) and 27 with intermittent asthma (mild asthma (MA) group) underwent a control session (no liquid, no resistor coil inside e-cigarette cartridge) and an experimental session of ECS using standardized puffing settings. Impulse oscillometry impedance (Z), resistance (R), reactance (X) and fractional exhaled nitric oxide (FeNO) were measured before and 0, 15 and 30 min after control and experimental sessions. RESULTS: Control session revealed no significant changes. In the experimental session, immediately post-ECS, both groups exhibited a significant increase in respiratory system total impedance at 5 Hz (Z5) (P < 0.001), respiratory system resistance at 5 Hz (R5) (P < 0.001), respiratory system resistance at 10 Hz (R10) (P < 0.001), respiratory system resistance at 20 Hz (R20) (P < 0.05), resonant frequency (P < 0.001) and reactance area (P < 0.05). MA exhibited higher baseline values and a more prominent effect immediately after ECS compared with HS for Z5 (P = 0.022), R5 (P = 0.010) and R10 (P = 0.013). FeNO decreased significantly in both groups (P < 0.001); HS returned to baseline values in ≤15 min while the MA maintained significantly lower values for an additional 15 min (P < 0.05) and returned to baseline values at 30 min post-ECS. CONCLUSION: A single session of ECS had respiratory mechanical and inflammatory effects, which were more prominent in smokers with asthma.

Accounting for effects of system dynamics to improve accuracy of emissions reported in e-cig vaping machines.

Laboratory emissions testing of electronic cigarettes continues to be a focus in the tobacco research community. In particular, to inform policy regarding appropriate test protocols to regulate the manufacture, marketing and sale of tobacco products. This study aims to enhance current understanding of the way laboratory systems used to generate topography profiles and capture resultant emissions from inhaled tobacco products may interact with the device under test. A programmable emission system (vaping machine) is introduced and characterized. The operating envelope of this system is presented. This study demonstrates that the performance of an emissions system may be influenced by various factors, resulting in discrepancies between command puff parameter inputs and the observed puffs generated. The study findings conclude that any emissions system should be characterized with the desired test device to determine the effective operating range of the system under "Load" conditions. Furthermore, reporting emissions from electronic cigarettes as a function of "command" puff flow rate and cumulative volume result in under-estimation bias and may give rise to incorrect conclusions regarding the impact of product characteristics on emissions. Conversely, reporting emissions in terms of "observed" puff flow rate and cumulative volume reduces bias errors and limits opportunity for intentional misrepresentation of results.

Assessment of tobacco heating product THP1.0. Part 1: Series introduction.

We have recently developed a Tobacco Heating Product (THP) comprising an electrical heating device, commercially known as Glo™, and consumable tobacco rods, commercially known as Kent Neostiks™. We refer to this system as THP1.0; Bright tobacco-flavoured variant THP1.0(T), or THP1.0(M) Menthol-flavoured variant. In this issue, we present a series of seven pre-clinical studies conducted on THP1.0,covering the following aspects of its design, development, safety and toxicological assessment, and a paper on placing THPs on an emissions continuum.

Assessment of tobacco heating product THP1.0. Part 2: Product design, operation and thermophysical characterisation.

A novel tobacco heating product, THP1.0, that heats tobacco below 245 °C is described. It was designed to eliminate tobacco combustion, while heating tobacco to release nicotine, tobacco volatiles and glycerol to form its aerosol. The stewardship assessment approach behind the THP 1.0 design was based on established toxicological principles. Thermophysical studies were conducted to examine the extent of tobacco thermal conversion during operation. Thermogravimetric analysis of the tobacco material revealed the major thermal behaviour in air and nitrogen up to 900 °C. This, combined with the heating temperature profiling of the heater and tobacco rod, verified that the tobacco was not subject to combustion. The levels of tobacco combustion markers (CO, CO2, NO and NOx) in the aerosol of THP1.0 were significantly lower than the levels if there were any significant pyrolysis or combustion. Quantification of other tobacco thermal decomposition and evaporative transfer markers showed that these levels were, on average, reduced by more than 90% in THP1.0 aerosol as compared with cigarette smoke. The physical integrity of the tobacco consumable rod showed no ashing. Taken together, these data establish that the aerosol generated by THP1.0 is produced mainly by evaporation and distillation, and not by combustion or pyrolysis.

Assessment of tobacco heating product THP1.0. Part 4: Characterisation of indoor air quality and odour.

The tobacco heating product THP1.0, which heats but does not burn tobacco, was tested as part of a modified-risk tobacco product assessment framework for its impacts on indoor air quality and residual tobacco smoke odour. THP1.0 heats the tobacco to less than 240 °C ± 5 °C during puffs. An environmentally controlled room was used to simulate ventilation conditions corresponding to residential, office and hospitality environments. An analysis of known tobacco smoke constituents, included CO, CO2, NO, NO2, nicotine, glycerol, 3-ethenyl pyridine, sixteen polycyclic aromatic hydrocarbons, eight volatile organic compounds, four carbonyls, four tobacco-specific nitrosamines and total aerosol particulate matter. Significant emissions reductions in comparison to conventional cigarettes were measured for THP1.0. Levels of nicotine, acetaldehyde, formaldehyde and particulate matter emitted from THP1.0 exceeded ambient air measurements, but were more than 90% reduced relative to cigarette smoke emissions within the laboratory conditions defined Residual tobacco smoke odour was assessed by trained sensory panels after exposure of cloth, hair and skin to both mainstream and environmental emissions from the test products. Residual tobacco smoke odour was significantly lower from THP1.0 than from a conventional cigarette. These data show that using THP1.0 has the potential to result in considerably reduced environmental emissions that affect indoor air quality relative to conventional cigarettes.

Assessment of tobacco heating product THP1.0. Part 8: Study to determine puffing topography, mouth level exposure and consumption among Japanese users.

A four-arm study was undertaken in Japan to determine the puffing topography, mouth level exposure and average daily consumption by consumers of the tobacco heating products (THPs): the non-mentholated THP1.0(T), the mentholated THP1.0(M) and a tobacco heating system (THS). The extent of lip blocking of air inlet holes while using THP1.0(T) was also assessed. Groups 1, 2, and 4 included smokers, and group 3 included regular THP users. Smokers of 7-8 mg ISO nicotine free dry particulate matter (NFDPM) non-mentholated cigarettes took on average larger mean puff volumes from THPs than from conventional cigarettes, but puff numbers and durations were similar. Mouth level exposure to NFDPM and nicotine levels were significantly lower when using THPs than conventional cigarettes. Similar trends were observed among smokers of 7-8 mg ISO NFDPM mentholated cigarettes who used mentholated cigarettes and THP1.0(M). Regular users of commercial THS had similar puffing behaviours irrespective of whether they were using THS or THP1.0(T), except for mean puff volume which was lower with THP1.0(T). No smokers blocked the air inlet holes when using THP1.0(T). The puffing topography results support the machine puffing regime used to generate toxicant emissions data and in vitro toxicology testing.

E-cigarettes, vaping and performativity in the context of tobacco denormalisation.

E-cigarettes are devices through which a nicotine solution is 'vapourised' and inhaled by the user. Unlike cigarettes, the process involves no tobacco combustion. However, the inhalation and exhalation of vapour is reminiscent of smoking and there is debate about the possible harms and benefits of e-cigarette use, including the 'renormalisation' of smoking. Despite these debates, there has been little exploration into the embodied and semiotic similarities between smoking and vaping. This paper views the practices of vaping and smoking through the lens of performativity that is, the accumulation of meaning associated with the habits over time and space. Through in-depth interviews, we explore how young adults from primarily disadvantaged areas in Scotland, understand the similarity in practices between smoking and vaping. Participants talked about financial barriers to using different types of e-cigarettes, and how their use reflected their views on smoking cessation. They also discussed the embodied similarities between smoking and vaping, with divergent opinions on whether this continuance of habit was beneficial or not, revealing still developing and ambiguous norms around performativity. The norms of vaping were also frequently discussed, with participants' experiences and views reflecting the contested position of vaping in an environment where cigarette smoking is denormalised.

Electronic cigarette vapor alters the lateral structure but not tensiometric properties of calf lung surfactant.

BACKGROUND: Despite their growing popularity, the potential respiratory toxicity of electronic cigarettes (e-cigarettes) remains largely unknown. One potential aspect of e-cigarette toxicity is the effect of e-cigarette vapor on lung surfactant function. Lung surfactant is a mixture of lipids and proteins that lines the alveolar region. The surfactant layer reduces the surface tension of the alveolar fluid, thereby playing a crucial role in lung stability. Due to their small size, particulates in e-cigarette vapor can penetrate the deep lungs and come into contact with the lung surfactant. The current study sought to examine the potential adverse effects of e-cigarette vapor and conventional cigarette smoke on lung surfactant interfacial properties. METHODS: Infasurf®, a clinically used and commercially available calf lung surfactant extract, was used as lung surfactant model. Infasurf® films were spread on top of an aqueous subphase in a Langmuir trough with smoke particulates from conventional cigarettes or vapor from different flavors of e-cigarettes dispersed in the subphase. Surfactant interfacial properties were measured in real-time upon surface compression while surfactant lateral structure after exposure to smoke or vapor was examined using atomic force microscopy (AFM). RESULTS: E-cigarette vapor regardless of the dose and flavoring of the e-liquid did not affect surfactant interfacial properties. In contrast, smoke from conventional cigarettes had a drastic, dose-dependent effect on Infasurf® interfacial properties reducing the maximum surface pressure from 65.1 ± 0.2 mN/m to 46.1 ± 1.3 mN/m at the highest dose. Cigarette smoke and e-cigarette vapor both altered surfactant microstructure resulting in an increase in the area of lipid multilayers. Studies with individual smoke components revealed that tar was the smoke component most disruptive to surfactant function. CONCLUSIONS: While both e-cigarette vapor and conventional cigarette smoke affect surfactant lateral structure, only cigarette smoke disrupts surfactant interfacial properties. The surfactant inhibitory compound in conventional cigarettes is tar, which is a product of burning and is thus absent in e-cigarette vapor.

"Juice Monsters": Sub-Ohm Vaping and Toxic Volatile Aldehyde Emissions.

An emerging category of electronic cigarettes (ECIGs) is sub-Ohm devices (SODs) that operate at ten or more times the power of conventional ECIGs. Because carcinogenic volatile aldehyde (VA) emissions increase sharply with power, SODs may expose users to greater VAs. In this study, we compared VA emissions from several SODs and found that across device, VAs and power were uncorrelated unless power was normalized by coil surface area. VA emissions and liquid consumed were correlated highly. Analyzed in light of EU regulations limiting ECIG liquid nicotine concentration, these findings suggest potential regulatory levers and pitfalls for protecting public health.

On the Origins of the Electronic Cigarette: British American Tobacco's Project Ariel (1962-1967).

Electronic cigarettes are advertised as the latest technological gadget-the smoking equivalent of smart phones. I challenge this sense of novelty by tracing their history to the 1960s, when researchers at British American Tobacco first recognized that smokers' brains were dependent on nicotine. This discovery enabled British American Tobacco to develop a novel kind of smoking device under the codename "Ariel" between 1962 and 1967. Whereas filters were meant to eliminate specific harmful constituents of tobacco smoke, Project Ariel tried to reduce smoking to its alkaloid essence: nicotine. By heating instead of burning tobacco, the scientists working on Ariel managed to produce an aerosol smoking device that delivered nicotine with very little tar while retaining the look and feel of a cigarette. However, after receiving two patents for Ariel, British American Tobacco ultimately decided to abandon the project to avoid endangering cigarettes, its main product. Today, as e-cigarettes are surging in popularity, it is worth revisiting Ariel because it is not just an episode in the history of aerosol smoking devices but its starting point.

An Electronic Cigarette Vaping Machine for the Characterization of Aerosol Delivery and Composition.

INTRODUCTION: Characterization of aerosols generated by electronic cigarettes (e-cigarettes) is one method used to evaluate the safety of e-cigarettes. While some researchers have modified smoking machines for e-cigarette aerosol generation, these machines are either not readily available, not automated for e-cigarette testing or have not been adequately described. The objective of this study was to build an e-cigarette vaping machine that can be used to test, under standard conditions, e-liquid aerosolization and nicotine and toxicant delivery. METHODS: The vaping machine was assembled from commercially available parts, including a puff controller, vacuum pump, power supply, switch to control current flow to the atomizer, three-way value to direct air flow to the atomizer, and three gas dispersion tubes for aerosol trapping. To validate and illustrate its use, the variation in aerosol generation was assessed within and between KangerTech Mini ProTank 3 clearomizers, and the effect of voltage on aerosolization and toxic aldehyde generation were assessed. RESULTS: When using one ProTank 3 clearomizer and different e-liquid flavors, the coefficient of variation (CV) of aerosol generated ranged between 11.5% and 19.3%. The variation in aerosol generated between ProTank 3 clearomizers with different e-liquid flavors and voltage settings ranged between 8.3% and 16.3% CV. Aerosol generation increased linearly at 3-6V across e-liquids and clearomizer brands. Acetaldehyde, acrolein, and formaldehyde generation increased markedly at voltages at or above 5V. CONCLUSION: The vaping machine that we describe reproducibly aerosolizes e-liquids from e-cigarette atomizers under controlled conditions and is useful for testing of nicotine and toxicant delivery. IMPLICATIONS: This study describes an electronic cigarette vaping machine that was assembled from commercially available parts. The vaping machine can be replicated by researchers and used under standard conditions to generate e-cigarette aerosols and characterize nicotine and toxicant delivery.

Electronic Cigarette Explosion Resulting in a C1 and C2 Fracture: A Case Report.

BACKGROUND: Electronic cigarettes have seen a drastic increase in use. A lithium-ion battery is often used as the rechargeable battery of the electronic cigarette device and has recently received much attention in terms of safety. There are several recent case reports in the scientific literature of injuries due to electronic cigarette explosions that involved soft-tissue injuries. CASE REPORT: We report a significant spinal fracture from an electronic-cigarette explosion in a 27-year-old male. The electronic cigarette exploded during use, sending the mouthpiece through the pharynx and into the first cervical vertebra and resulting in fractures of the first and second vertebrae. An x-ray study of the neck showed a foreign body in the neck at the level of C1. A computed tomography scan of the neck showed fractures of C1. The foreign body was removed in the operating room. The patient was discharged home without neurologic sequelae. WHY SHOULD AN EMERGENCY PHYSICIAN BE AWARE OF THIS?: Our case report is the first case of a cervical spine injury due to the explosion of an electronic cigarette. This case demonstrates that an electronic cigarette explosion can cause potentially serious penetrating neck injury. Emergency physicians should be aware of the potential danger of electronic cigarettes and have a low threshold to obtain radiographic tests and surgical consultation in the case of electronic cigarette explosion in the oral cavity. As the use of electronic cigarettes continue to increase, it is likely that injuries associated with them will also increase.