A comparison of the electrical characteristics, liquid composition, and toxicant emissions of JUUL USA and JUUL UK e-cigarettes.
Ontology highlight
ABSTRACT:
SUBMITTER: Talih S
PROVIDER: S-EPMC7192936 | biostudies-literature | 2020 Apr
REPOSITORIES: biostudies-literature
Publications
A comparison of the electrical characteristics, liquid composition, and toxicant emissions of JUUL USA and JUUL UK e-cigarettes.
Talih Soha S Salman Rola R El-Hage Rachel R Karam Ebrahim E Salam Sally S Karaoghlanian Nareg N El-Hellani Ahmad A Saliba Najat N Shihadeh Alan A
Scientific reports 20200430 1
In 2018, JUUL entered the UK market, where EU regulations limit liquid nicotine concentration to 20 mg/mL, approximately one-third the level of JUUL products sold in the USA. We hypothesized that JUUL's UK product was engineered to deliver greater electrical power and boost liquid vaporization such that the net nicotine delivery rate was similar to the US version. We compared electrical characteristics, liquid composition, and aerosol emissions of JUUL devices procured in the USA and the UK. Stu ...[more]
Similar Datasets
Project description:IntroductionJUUL is an electronic cigarette (ECIG) with a compact form factor. It is prefilled with a liquid that is advertised to contain a high concentration of nicotine salt. JUUL commands 50% of the US ECIG market share, and its wide popularity with underage users has triggered unprecedented actions by the US FDA. Apart from its nicotine salt-containing liquid and compact form, a salient advertised design feature is a control circuit that limits the heating coil temperature, presumably reducing unwanted toxicants. In this study, several tobacco-flavoured JUUL devices were reverse engineered, and their aerosol emissions were studied.MethodsTotal nicotine and its partitioning (freebase and protonated), propylene glycol/vegetable glycerin (PG/VG) ratio, and carbonyls were quantified by gas chromatography (GC) and high performance liquid chromatography (HPLC). The temperature control functionality of JUUL was investigated using a temperature-controlled bath in which the coil was submerged.ResultsThe liquid nicotine concentration was found to be 69 mg/mL, and the liquid and aerosol PG/VG ratio was found to be 30/70. In 15 puffs, JUUL emitted 2.05 (0.08) mg of nicotine, overwhelmingly in the protonated form. Carbonyl yields were significantly lower than those reported for combustible cigarettes, but similar to other closed-system ECIG devices. The heating coil resistance was 1.6 (0.66) Ohm, while the maximum power delivered by the JUUL device was 8.1 W. The control circuit limited the peak operating temperature to approximately 215C.ConclusionsJUUL emits a high-nicotine concentration aerosol predominantly in the protonated form. JUUL's nicotine-normalised formaldehyde and total aldehyde yields are lower than other previously studied ECIGs and combustible cigarettes.
| S-EPMC7341718 | biostudies-literature
Project description:IntroductionUse of flavoured pod-mod-like disposable electronic cigarettes (e-cigarettes) has grown rapidly, particularly among cost-sensitive youth and young adults. To date, little is known about their design characteristics and toxicant emissions. In this study, we analysed the electrical and chemical characteristics and nicotine and pulmonary toxicant emission profiles of five commonly available flavoured disposable e-cigarettes and compared these data with those of a JUUL, a cartridge-based e-cigarette device that pod-mod-like disposables emulate in size and shape.MethodsDevice construction, electrical power and liquid composition were determined. Machine-generated aerosol emissions including particulate matter, nicotine, carbonyl compounds and heavy metals were also measured. Liquid and aerosol composition were measured by high-performance liquid chromatography, gas chromatography-mass spectrometry/flame ionisation detection, and inductively coupled plasma mass spectrometry.ResultsWe found that unlike JUUL, disposable devices did not incorporate a microcontroller to regulate electrical power to the heating coil. Quality of construction varied widely. Disposable e-cigarette power ranged between 5 and 9 W and liquid nicotine concentration ranged between 53 and 85 mg/mL (~95% in the protonated form). In 15 puffs, total nicotine yield for the disposables ranged between 1.6 and 6.7 mg, total carbonyls ranged between 28 and 138 µg, and total metals ranged between 1084 and 5804 ng. JUUL emissions were near the floors of all of these ranges.ConclusionsDisposable e-cigarettes are designed with high nicotine concentration liquids and are capable of emitting much higher nicotine and carbonyl species relative to rechargeable look-alike e-cigarettes. These differences are likely due to the lower quality in construction, unreliable labelling and lack of temperature control regulation that limits the power during operation. From a public health perspective, regulating these devices is important to limit user exposure to carbonyls and nicotine, particularly because these devices are popular with youth and young adults.
| S-EPMC8586044 | biostudies-literature
Project description:IntroductionJUUL, a small pod-based vaping device that aerosolizes nicotine salts, is popular among adolescents and young adults. Because of JUUL's high nicotine content, JUUL users can become nicotine dependent very quickly and have difficulty quitting. Nicotine-dependent JUUL users might turn to Twitter to seek advice, share their cessation struggles, or report their success rather than confiding in friends or family.MethodThis study analyzed Twitter tweets (N = 3192) posted in 2018-2019 to identify common themes about quitting JUUL. Tweets containing the keywords "JUUL" and "quit" or "quitting" were analyzed qualitatively and grouped into themes.ResultsThe most common themes were Methods to quit (25.4%), Have quit (17.8%), Want to quit (16.1%), Reasons to quit (9.6%), Difficulty quitting (7.9%), Barriers to quitting (2.9%), and Curious about quitting (2.1%). Methods to quit included evidence-based tobacco cessation methods such as nicotine replacement therapy and enrolling in a text-to-quit program, but they also included non-evidence-based strategies such as buying lower-nicotine pods online or switching to other tobacco products including cigarettes. Former JUUL users who had quit successfully generally expressed pride but also acknowledged that quitting was very difficult. Reasons for quitting included adverse health effects such as breathing problems and the financial cost of a JUUL habit. Posters mentioned their extreme difficulty quitting JUUL, numerous failed quit attempts, and numerous barriers to quitting including intense physical and emotional withdrawal symptoms. Some posters joked about switching to cigarettes or other drugs to quit JUUL.ConclusionResults indicate that JUUL cessation is difficult and that some JUUL users want to quit. Health communication messages are needed to direct JUUL users to effective cessation strategies.
| S-EPMC7330876 | biostudies-literature
Project description:IntroductionAvailable 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.MethodsTwenty-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.ResultsNicotine 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.ConclusionIn 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.ImplicationsPeriodic surveying of characteristics of ECIG products available in the marketplace is valuable for understanding population-wide changes in ECIG use patterns over time.
| S-EPMC5896517 | biostudies-literature
Project description:Electronic cigarettes (ECIGs) heat and vaporize a liquid mixture to produce an inhalable aerosol that can deliver nicotine to the user. The liquid mixture is typically composed of propylene glycol (PG) and vegetable glycerin (VG), in which are dissolved trace quantities of flavorants and, usually, nicotine. Due to their different chemical and thermodynamic properties, the proportions of PG and VG in the liquid solution may affect nicotine delivery and user sensory experience. In social media and popular culture, greater PG fraction is associated with greater "throat-hit", a sensation that has been attributed in cigarette smokers to increased presence of vapor-phase nicotine. VG, on the other hand, is associated with thicker and larger exhaled "clouds". In this study, we aim to investigate how PG/VG ratio influences variables that relate to nicotine delivery and plume visibility. Aerosols from varying PG/VG liquids were generated using a digitally controlled vaping instrument and a commercially available ECIG, and analyzed for nicotine content by GC-MS. Particle mass and number distribution were determined using a six-stage cascade impactor and a fast particle spectrometer (TSI EEPS), with tightly controlled dilution and sampling biases. A Mie theory model was used to compute the aerosol scattering coefficients in the visible spectrum. Decreasing the PG/VG ratio resulted in a decrease in total particulate matter (TPM) and nicotine yield (R2 > 0.9, p<.0001). Measured particle count median diameter ranged between 44-97nm, and was significantly smaller for PG liquids. Although the particle mass concentration was lower, aerosols produced using liquids that contained VG had an order of magnitude greater light scattering coefficients. These findings indicate that PG/VG ratio is a strong determinant of both nicotine delivery and user sensory experience.
| S-EPMC7453347 | biostudies-literature
Project description:ImportanceUse of electronic cigarettes (e-cigarettes) is increasing. Measures of exposure to known tobacco-related toxicants among e-cigarette users will inform potential health risks to individual product users.ObjectivesTo estimate concentrations of tobacco-related toxicants among e-cigarette users and compare these biomarker concentrations with those observed in combustible cigarette users, dual users, and never tobacco users.Design, setting, and participantsA population-based, longitudinal cohort study was conducted in the United States in 2013-2014. Cross-sectional analysis was performed between November 4, 2016, and October 5, 2017, of biomarkers of exposure to tobacco-related toxicants collected by the Population Assessment of Tobacco and Health Study. Participants included adults who provided a urine sample and data on tobacco use (N = 5105).ExposuresThe primary exposure was tobacco use, including current exclusive e-cigarette users (n = 247), current exclusive cigarette smokers (n = 2411), and users of both products (dual users) (n = 792) compared with never tobacco users (n = 1655).Main outcomes and measuresGeometric mean concentrations of 50 individual biomarkers from 5 major classes of tobacco product constituents were measured: nicotine, tobacco-specific nitrosamines (TSNAs), metals, polycyclic aromatic hydrocarbons (PAHs), and volatile organic compounds (VOCs).ResultsOf the 5105 participants, most were aged 35 to 54 years (weighted percentage, 38%; 95% CI, 35%-40%), women (60%; 95% CI, 59%-62%), and non-Hispanic white (61%; 95% CI, 58%-64%). Compared with exclusive e-cigarette users, never users had 19% to 81% significantly lower concentrations of biomarkers of exposure to nicotine, TSNAs, some metals (eg, cadmium and lead), and some VOCs (including acrylonitrile). Exclusive e-cigarette users showed 10% to 98% significantly lower concentrations of biomarkers of exposure, including TSNAs, PAHs, most VOCs, and nicotine, compared with exclusive cigarette smokers; concentrations were comparable for metals and 3 VOCs. Exclusive cigarette users showed 10% to 36% lower concentrations of several biomarkers than dual users. Frequency of cigarette use among dual users was positively correlated with nicotine and toxicant exposure.Conclusions and relevanceExclusive use of e-cigarettes appears to result in measurable exposure to known tobacco-related toxicants, generally at lower levels than cigarette smoking. Toxicant exposure is greatest among dual users, and frequency of combustible cigarette use is positively correlated with tobacco toxicant concentration. These findings provide evidence that using combusted tobacco cigarettes alone or in combination with e-cigarettes is associated with higher concentrations of potentially harmful tobacco constituents in comparison with using e-cigarettes alone.
| S-EPMC6324349 | biostudies-literature
Project description:Flavors in electronic cigarette (ECIG) liquids may increase ECIG aerosol toxicity via intact distillation or chemical transformation. For this report, we performed a meta-analysis of the literature to categorize the compounds found in flavored ECIG liquids into a few chemical classes and to predict their possible chemical transformations upon ECIG liquid aerosolization. This analysis allowed us to propose specific correlations between flavoring chemicals and aerosol toxicants. A literature search was conducted in November 2019 using PubMed. Keywords included terms related to ECIGs and flavors. Studies were included if they reported chemical ingredients of flavored liquids and clearly stated the commercial names of these liquids. The obtained data were visualized on a network diagram to show the common chemical compounds identified in flavored ECIG liquids and categorize them into different chemical classes. The systematic literature review included a total of 11 articles. Analysis of the data reported gave a total of 189 flavored liquids and 173 distinct chemical compounds that were categorized into 22 chemical classes according to their functional groups. The subsequent prediction of chemical transformations of these functional groups highlighted the possible correlation of flavor compounds to aerosol toxicants.
| S-EPMC7759004 | biostudies-literature
Project description:Cigarette smoking causes serious diseases through frequent and prolonged exposure to toxicants. Technologies are being developed to reduce smokers' toxicant exposure, including filter adsorbents, tobacco treatments and substitutes. This study examined the effect of modifications to filter ventilation, variations in cigarette circumference and active charcoal filter length and loading, as well as combinations of these features in a reduced-toxicant prototype (RTP) cigarette, on the yields of toxicants in cigarette smoke. An air-dilution mechanism, called split-tipping, was developed in which a band of porous paper in the centre of the filter tipping functions to minimise the loss of effective filter ventilation that occurs at the high flow rates encountered during human-smoking, and to facilitate the diffusional loss of volatile toxicants. As compared with conventional filter ventilation cigarettes, split-tipping reduced tar and volatile smoke constituent emissions under high flow rate machine-smoking conditions, most notably for products with a 1-mg ISO tar yield. Furthermore, mouth level exposure (MLE) to tar and nicotine was reduced among smokers of 1-mg ISO tar cigarettes in comparison to smokers of cigarettes with traditional filter ventilation. For higher ISO tar level cigarettes, however, there were no significant reductions in MLE. Smaller cigarette circumferences reduced sidestream toxicant yields and modified the balance of mainstream smoke chemistry with reduced levels of aromatic amines and benzo[a]pyrene but increased yields of formaldehyde. Smaller circumference cigarettes also had lower mainstream yields of volatile toxicants. Longer cigarette filters containing increased levels of high-activity carbon (HAC) showed reduced machine-smoking yields of volatile toxicants: with up to 97% removal for some volatile toxicants at higher HAC loadings. Split-tipping was combined with optimal filter length and cigarette circumference in an RTP cigarette that gave significantly lower mainstream (up to ~90%) and sidestream (predominately 20%-60%) smoke yields of numerous toxicants as compared with a commercial comparator cigarette under machine-smoking conditions. Significantly lower mainstream and sidestream smoke toxicant yields were observed for an RTP cigarette comprising several toxicant reducing technologies; these observations warrant further evaluation in clinical studies where real-world relevance can be tested using biomarkers of exposure and physiological effect.
| S-EPMC4125608 | biostudies-literature
Project description:PurposeTo estimate the prevalence, patterns, and correlates of self-reported nicotine dependence symptoms among U.S. youth who use JUUL - a widely-sold e-cigarette brand - in 2019 and compare findings to nicotine dependence symptoms in youth who smoke cigarettes.MethodsData were from a nationally-representative subsample of 8th, 10th, and 12th grade students in the Monitoring the Future Study who had used JUUL or cigarettes in the past 30 days. Participants self-reported presence/absence of 9 different nicotine dependence symptoms for JUUL or cigarettes. Weighted percentages for JUUL or cigarette nicotine dependence symptom status (≥1 vs. 0 symptoms) and severity (count, range: 0-9) were calculated. Among JUUL users, we estimated associations of sociodemographic characteristics and other substance use with nicotine dependence and severity.ResultsAmong 1,748 past 30-day JUUL users, 41.3 % screened positive for ≥1 nicotine dependence symptoms; the mean symptom count was 1.6 (SD = 2.6). Non-nicotine substance use and more frequent JUUL use was associated with significantly greater odds of dependence and more severe dependence symptoms in multivariable models. The severity distribution of most (craving) and least (inability to quit) dependence symptom types observed in JUUL dependence paralleled those observed in analysis of combustible cigarette dependence symptoms in past 30-day smokers.ConclusionA substantial proportion of U.S. adolescent JUUL users reported symptoms of nicotine dependence, which is greater for those who vape more frequently and use other substances. Nicotine dependence screening, prevention, and regulatory policies addressing use of JUUL or similar e-cigarette products should be considered to protect U.S. youth.
| S-EPMC8464491 | biostudies-literature
Project description:BackgroundThe short and long-term health effects of JUUL electronic cigarette (e-Cig) are largely unknown and warrant extensive research. We hypothesized that JUUL exposure could cause cerebrovascular toxicities impacting the progression and outcome of ischemic stroke comparable to tobacco smoke (TS) exposure.MethodsWe exposed male C57 mice to TS/JUUL vapor for 14 days. LCMS/MS was used to measure brain and plasma nicotine and cotinine level. Transient middle cerebral artery occlusion (tMCAO) followed by reperfusion was used to mimic ischemic stroke. Plasma levels of IL-6 and thrombomodulin were assessed by enzyme-linked immunosorbent assay. At the same time, western blotting was used to study blood-brain barrier (BBB) tight junction (TJ) proteins expression and key inflammatory and oxidative stress markers.ResultstMCAO upregulated IL-6 and decreased plasma thrombomodulin levels. Post-ischemic brain injury following tMCAO was significantly worsened by JUUL/TS pre-exposure. TJ proteins expression was also downregulated by JUUL/TS pre-exposure after tMCAO. Like TS, exposure to JUUL downregulated the expression of the antioxidant Nrf2. ICAM-1 was upregulated in mice subjected to tMCAO following pre-exposure to TS or JUUL, with a greater effect of TS than JUUL.ConclusionsThese results suggest that JUUL exposure could negatively impact the cerebrovascular system, although to a lesser extent than TS exposure.
| S-EPMC9463848 | biostudies-literature