Low-temperature (< 200 °C) degradation of electronic nicotine delivery system liquids generates toxic aldehydes.
Ontology highlight
ABSTRACT:
SUBMITTER: Jaegers NR
PROVIDER: S-EPMC8032854 | biostudies-literature |
REPOSITORIES: biostudies-literature
Similar Datasets
Project description:Electronic nicotine delivery systems (ENDS) are prefilled, battery-operated products intended to deliver nicotine to the user via an inhaled complex aerosol formed by heating a liquid composed of propylene glycol and glycerol, also referred to as vegetable glycerin and collectively called e-liquid, that contains nicotine and various flavor ingredients. Since their introduction in 2006, the number of ENDS on the market has increased exponentially. Despite their growing ubiquity, the possible health risks associated with ENDS use remain poorly understood. One potential concern is the presence of toxic metals in the e-liquid and aerosol. Herein, we report the evaluation of the metal content in the e-liquids from a series of commercially available cigalike ENDS brands (various flavors) determined using inductively coupled plasma mass spectrometry (ICP-MS) following e-liquid extraction. Each brand of cigalike ENDS was purchased at least three times at retail outlets in the Baltimore, Maryland metropolitan region over a period of six months (September 2017 to February 2018). This allowed for comparison of batch-to-batch variability. Several potentially toxic metals, including lead, chromium, copper, and nickel were detected in the e-liquids. In addition, high variability in metal concentrations within and between brands and flavors was observed . The internal assembled parts of each cartridge were analyzed by X-ray imaging, before dissembling so that the materials used to manufacture each cartridge could be evaluated to determine the metals they contained. Following washing to remove traces of e-liquid, lead, chromium, copper and nickel were all detected in the cigalike ENDS prefilled cartridges, suggesting one potential source for the metals found in the e-liquids. Collectively, these findings can inform further evaluation of product design and manufacturing processes, including quantification of metal concentrations in e-liquids over foreseeable storage times, safeguards against high concentrations of metals in the e-liquid before and after aerosolization (by contact with a metal heating coil), and control over batch-to-batch variability.
| S-EPMC7368082 | biostudies-literature
Project description:OBJECTIVES:For electronic nicotine delivery systems (ENDS), also commonly called e-cigarettes, coil temperature is a factor in the potential production of toxic chemical constituents. However, data are lacking regarding the temperatures that are achieved in the latest generation of these devices. Fourth-generation ENDS are capable of producing heating coil temperatures well above e-liquid boiling points, and allow the user to monitor and set the heating coil temperature during a puff. In this study, we evaluate the accuracy and consistency of the temperature measurement and control settings for different brands of fourth-generation ENDS. METHODS:A study was performed using three commercially available, fourth-generation ENDS. The atomizer coil temperatures were obtained from the device (using the EScribe software) reading and from thermocouples attached to the coils during simulated puffing conditions. In addition, aerosol temperatures were measured inside the atomizer and at the mouthpiece. RESULTS:Measured temperatures varied widely across samples taken from the same brand. For example, thermocouple measurements for one unit were 40 Celsius (°C) below the 300 °C set point, while another unit of the same brand exceeded the set point by more than 100 °C. We observed a significant variation in temperature (approximately 100 °C) along the length of the coil in some cases. CONCLUSIONS:The possibility of wide temperature variation across ENDS samples, as well as variations between maximum coil temperatures and internal temperature readings, may have implications for studies that seek to determine correlations between coil temperature and toxin generation.
| S-EPMC6218080 | biostudies-literature
Project description:Electronic cigarettes (ECIGs) are appealing in part because of the many flavors of the liquids used in them. Concerns have been raised that some ECIG liquid flavors, especially those that are sweet, are attracting otherwise nicotine-naïve youth to ECIGs. Sucralose is an artificial, non-caloric sweetener that is added to some ECIG liquids. In this study, we evaluated the toxicants, namely isomers of chloropropanols that can be produced when sucralose-containing ECIG liquid is aerosolized. An analytical separation method relying on solid-phase extraction (SPE) to isolate chloropropanols from the propylene glycol/glycerol matrix was developed. Chloropropanols were then derivatized by silylation before they were analyzed on GC-MS. The influence of different ECIG operating conditions on the generation of chloropropanols was studied by varying ECIG device design and power output and also the sucralose concentration of the liquid. Heated sucralose-containing ECIG liquids produce two toxic compounds that can be found in the resulting aerosols. The two chloropropanols, 3-monochloro-1,2-propanediol (3-MCPD) and 1,3-dichloropropanol (1,3-DCP) that were detected under all conditions were found to be correlated significantly with liquid sucralose content. Effective regulation of ECIGs will minimize user and bystander exposure to these and other ECIG toxicants.
| S-EPMC9733909 | biostudies-literature
Project description:The electronic cigarette (e-cigarette) has emerged as popular electronic nicotine delivery devices (ENDs). However, the general safety and validity of e-cigarettes for nicotine delivery efficacy are still not well understood. This study developed a new method for efficient measurement of nicotine levels in both the liquids (e-liquids) used in e-cigarettes and the aerosols generated from the e-cigarettes. Protonation of the pyrrolidine nitrogen of nicotine molecules by addition of excess hydrochloric acid affords an aminium salt that is readily quantified by Fourier transform ion cyclotron mass spectrometry (FT-ICR-MS). The kinetics of nicotine protonation was studied using 1H NMR spectroscopy. Quantitative analyses of nicotine in commercial e-liquids and in the corresponding derived e-cigarette aerosols were carried out using direct infusion FT-ICR-MS. The 1H NMR study of nicotine protonation revealed a first order reaction and an activation energy of 30.05 kJ mol-1. The nicotine levels measured in the commercial e-liquids were within a wide and highly variable range of -2.94% to +25.20% around the manufacturer's stated values. The results indicated considerable differences between the measured levels and the advertised levels of nicotine in the e-liquids. The nicotine quantity measured in aerosols increased linearly both with nicotine level in e-liquids (same number of puffs) and with number of puffs (same e-liquids). These data show that quality control of e-liquids and use characteristics are major variables in efficacy of nicotine delivery.
| S-EPMC5703602 | biostudies-literature
Project description:E-liquids usually contain significant nicotine, which will exist primarily in two forms, monoprotonated and free-base, the proportions of which are alterable through the effective pH of the medium. The fraction of nicotine in the free-base form is αfb, with 0 ≤ αfb ≤ 1. When dosed via aerosol, the two nicotine forms have different mechanisms and kinetics of delivery, as well as differing implications for harshness of the inhaled aerosol, so αfb is relevant regarding abuse liability. Previous attempts to determine αfb in electronic cigarette liquids and vapor have been flawed. We employed the exchange-averaged 1H NMR chemical shifts of nicotine to determine αfb in samples of e-liquids. This method is rapid and direct and can also be used with collected aerosol material. The e-liquids tested were found to have 0.03 ≤ αfb ≤ 0.84. The αfb values in collected aerosol liquid samples were highly correlated with those for the parent e-liquids. E-liquids designed to combine high total nicotine level (addictive delivery) with low αfb (for ease of inhalation) are likely to be particularly problematic for public health.
| S-EPMC6008736 | biostudies-literature
Project description:BackgroundThere are concerns that the use of electronic nicotine delivery systems (ENDS) and electronic non-nicotine delivery systems (ENNDS) in children and adolescents could potentially be harmful to health. Understanding the extent of use of these devices is crucial to informing public health policy. We aimed to synthesise the prevalence of ENDS or ENNDS use in children and adolescents younger than 20 years.MethodsIn this systematic review and meta-analysis, we undertook an electronic search in five databases (MEDLINE, Web of Science, Cumulative Index to Nursing and Allied Health Literature, Embase, and Wiley Cochrane Library) from Jan 1, 2016, to Aug 31, 2020, and a grey literature search. Included studies reported on the prevalence of ENDS or ENNDS use in nationally representative samples in populations younger than 20 years and collected data between the years 2016 and 2020. Studies were excluded if they were done in those aged 20 years or older, used data from specialist panels that did not apply appropriate weighting, or did not use methods that ensured recruitment of a nationally representative sample. We included the most recent data for each country. We combined multiple national estimates for a country if they were done in the same year. We undertook risk of bias assessment for all surveys included in the review using the Joanna Briggs Institute Critical Appraisal Checklist (by two reviewers in the author list). A random effects meta-analysis was used to pool overall prevalence estimates for ever, current, occasional, and daily use. This study was prospectively registered with PROSPERO, CRD42020199485.FindingsThe most recent prevalence data from 26 national surveys representing 69 countries and territories, with a median sample size of 3925 (IQR 1=2266, IQR 3=10 593) children and adolescents was included. In children and adolescents aged between 8 years and younger than 20 years, the pooled prevalence for ever (defined as any lifetime use) ENDS or ENNDS use was 17·2% (95% CI 15-20, I2=99·9%), whereas for current use (defined as use in past 30 days) the pooled prevalence estimate was 7·8% (6-9, I2=99·8%). The pooled estimate for occasional use was 0·8% (0·5-1·2, I2=99·4%) for daily use and 7·5% (6·1-9·1, I2=99·4%) for occasional use. Prevalence of ENDS or ENNDS use was highest in high-income geographical regions. In terms of study quality, all surveys scored had a low risk of bias for the sampling frame used, due to the nationally representative nature of the studies. The most poorly conducted methodological feature of the included studies was subjects and setting described in detail. Few surveys reported on the use of flavours or types of ENDS or ENNDS.InterpretationThere is significant variability in the prevalence of ENDS and ENNDS use in children and adolescents globally by country income status. These findings are possibly due to differences in regulatory context, market availability, and differences in surveillance systems.FundingWorld Health Organization and the Bill & Melinda Gates Foundation.
| S-EPMC8390387 | biostudies-literature
Project description:UnlabelledTo determine the accuracy of the labeled quantity of the nicotine content of the e-liquids sold in unlicensed vape stores, whether the packaging of e-liquids sold within the vape stores was child-resistant, whether minors were present within vape stores, and whether sales to minors occurred. This study was conducted across North Dakota prior to implementation of a new e-cigarette state law and provided a baseline assessment before enactment of the new legal requirements.Design and methodsWe tested samples of e-liquids and performed observations in 16 stores that were selling e-cigarettes but were not legally required to be licensed for tobacco retail. The e-liquids were analyzed for nicotine content using a validated high-performance liquid chromatography method for nicotine analysis.ResultsOf the 70 collected e-liquid samples that claimed to contain nicotine, 17% contained more than the labeled quantity and 34% contained less than the labeled quantity by 10% or more, with one sample containing 172% more than the labeled quantity. Of the 94 e-liquid containers sampled, only 35% were determined to be child-resistant. Minors were present in stores, although no sales to minors occurred.ConclusionsMislabeling of nicotine in e-liquids is common and exposes the user to the harmful effects of nicotine. The lack of child-resistant packaging for this potentially toxic substance is a serious public health problem. E-cigarettes should be included in the legal definition of tobacco products, child-resistant packaging and nicotine labeling laws should be enacted and strictly enforced, and vape stores should be licensed by states.
| S-EPMC4914438 | biostudies-literature
Project description:Some jurisdictions have instituted limits on electronic cigarette (ECIG) liquid nicotine concentration, in an effort to control ECIG nicotine yield, and others are considering following suit. Because ECIG nicotine yield is proportional to the product of liquid nicotine concentration (milligram per millilitre) and device power (watts) regulations that limit liquid nicotine concentration may drive users to adopt higher wattage devices to obtain a desired nicotine yield. In this study we investigated, under various hypothetical regulatory limits on ECIG liquid nicotine concentration, a scenario in which a user of a common ECIG device (SMOK TF-N2) seeks to obtain in 15 puffs the nicotine emissions equivalent to one combustible cigarette (ie, 1.8 mg). We measured total aerosol and carbonyl compound (CC) yields in 15 puffs as a function of power (15-80 W) while all else was held constant. The estimated nicotine concentration needed to achieve combustible cigarette-like nicotine yield at each power level was then computed based on the measured liquid consumption. We found that for a constant nicotine yield of 1.8 mg, reducing the liquid nicotine concentration resulted in greater amount of liquid aerosolised (p<0.01) and greater CC emissions (p<0.05). Thus, if users seek a given nicotine yield, regulatory limits on nicotine concentration may have the unintended consequence of increasing exposure to aerosol and respiratory toxicants. This outcome demonstrates that attempting to control ECIG nicotine yield by regulating one factor at a time may have unintended health effects and highlights the need to consider multiple factors and outcomes simultaneously when designing regulations.
| S-EPMC9281877 | biostudies-literature
Project description:AIMS:To estimate the effect of potential regulations of electronic nicotine delivery systems (ENDS) among adult smokers, including increasing taxes, reducing flavor availability and adding warning labels communicating various levels of risk. DESIGN:We performed a discrete choice experiment (DCE) among a national sample of 1200 adult smokers. We examined heterogeneity in policy responses by age, cigarette quitting interest and current ENDS use. Our experiment overlapped January 2015 by design, providing exogenous variation in cigarette quitting interest from New Year resolutions. SETTING:KnowledgePanel, an online panel of recruited respondents. PARTICIPANTS:A total of 1200 adult smokers from the United States. MEASUREMENTS:Hypothetical purchase choice of cigarettes, nicotine replacement therapy and a disposable ENDS. FINDINGS:Increasing ENDS prices from $3 to $6 was associated with a 13.6 percentage point reduction in ENDS selection (P < 0.001). Restricting flavor availability in ENDS to tobacco and menthol was associated with a 2.1 percentage point reduction in ENDS selection (P < 0.001). The proposed Food and Drug Administration (FDA) warning label was associated with a 1.1 percentage point reduction in ENDS selection (P < 0.05) and the MarkTen warning label with a 5.1 percentage point reduction (P < 0.001). We estimated an ENDS price elasticity of -1.8 (P < 0.001) among adult smokers. Statistically significant interaction terms (P < 0.001) imply that price responsiveness was higher among adult smokers 18-24 years of age, smokers who have vaped over the last month and smokers with above the median quitting interest. Young adult smokers were 3.7 percentage points more likely to choose ENDS when multiple flavors were available than older adults (P < 0.001). Young adult smokers and those with above the median cigarette quitting interest were also more likely to reduce cigarette selection and increase ENDS selection in January 2015 (P < 0.001), potentially in response to New Year's resolutions to quit smoking. CONCLUSIONS:Increased taxes, a proposed US Food and Drug Administration warning label for electronic nicotine delivery systems and a more severe warning label may discourage adult smokers from switching to electronic nicotine delivery systems. Reducing the availability of flavors may reduce ENDS use by young adult smokers.
| S-EPMC4801654 | biostudies-literature
Project description:IntroductionCigarette smoking is a known risk factor for postoperative complications. Quitting or cutting down on cigarettes around the time of surgery may reduce these risks. This study aimed to determine the feasibility of using electronic nicotine delivery systems (ENDS) to help patients achieve this goal, regardless of their intent to attempt long-term abstinence.MethodsAn open-label observational study was performed of cigarette smoking adults scheduled for elective surgery at Mayo Clinic Rochester and seen in the pre-operative evaluation clinic between December 2014 and June 2015. Subjects were given a supply of ENDS to use prior to and 2 weeks after surgery. They were encouraged to use them whenever they craved a cigarette. Daily use of ENDS was recorded, and patients were asked about smoking behavior and ENDS use at baseline, 14 days and 30 days.ResultsOf the 105 patients approached, 80 (76%) agreed to participate; five of these were later excluded. Among the 75, 67 (87%) tried ENDS during the study period. At 30-day follow-up, 34 (51%) who had used ENDS planned to continue using them. Average cigarette consumption decreased from 15.6 per person/d to 7.6 over the study period (P < .001). At 30 days, 11/67 (17%) reported abstinence from cigarettes.ConclusionENDS use is feasible in adult smokers scheduled for elective surgery and is associated with a reduction in perioperative cigarette consumption. These results support further exploration of ENDS as a means to help surgical patients reduce or eliminate their cigarette consumption around the time of surgery.ImplicationsSmoking in the perioperative period increases patients' risk for surgical complications and healing difficulties, but new strategies are needed to help patients quit or cut down during this stressful time. These pilot data suggest that ENDS use is feasible and well-accepted in surgical patients, and worthy of exploration as a harm reduction strategy in these patients.
| S-EPMC5942518 | biostudies-literature