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Trajectories of E-Cigarette and Conventional Cigarette Use Among Youth

Trajectories of E-Cigarette and Conventional Cigarette Use Among Youth

Analyses were run by using Mplus (version 7.4). Outcome data were missing for 6.5% of cases across waves and were handled by using maximum likelihood estimation with robust standard errors. Past- month cigarette and e-cigarette use outcomes were modeled as binary variables with a logit link function. School was included as a covariate across all waves to account for potential school cohort effects. Path models were used to simultaneously estimate the following: (1) the autoregressive direct effects within cigarette and e-cigarette use across waves (ie, the association between e-cigarette and cigarette use at each wave and use of the same product at the next wave) and (2) the reciprocal predictive pathways between e-cigarette and cigarette use at each wave to use of the other product at the next wave (eg, e-cigarette use at wave 1 predicting cigarette use at wave 2 and vice versa) (see Fig 1). Baseline variables such as sociodemographic characteristics and use of other tobacco products (ie, cigars, hookah, blunts, smokeless tobacco) were selected a priori as covariates on the basis of previous literature. 19, 20 Results were
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E cigarette access among young people in Cheshire and Merseyside

E cigarette access among young people in Cheshire and Merseyside

Ecigarette  access  was  most  common  among  young people that smoked tobacco cigarettes,  with  two  thirds  of  regular  tobacco  smokers  having  accessed  e‐cigarettes.  This  shows  a  widespread  engagement  of  young  smokers  with  these  nicotine  delivery  devices;  and  that  e‐cigarettes  are  reaching  those  that  may  benefit  from  their use in terms of  reducing or  preventing  tobacco  smoking.  However,  while  some  teenage  smokers  may  have  accessed  e‐ cigarettes  to  help  them  give  up  smoking,  prevalence  of  ecigarette  access  among  ex‐ smokers  was  lower  (40.3%)  than  that  for  regular  smokers,  and  ex‐smokers  only  accounted  for  12.8%  of  all  students  that  had  accessed  e‐cigarettes  (compared  with  42.8%  being regular smokers).  Thus, findings provide  little  support  for  e‐cigarettes  being  used  by  young smokers in Cheshire  & Merseyside as a  tobacco‐smoking cessation  tool.  This  backs up  findings  from  the  qualitative  study, 13   which  suggested that while some older teenagers did  see  e‐cigarettes  as  a  mechanism  of  reducing  tobacco  smoking,  e‐cigarettes  were  largely 
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E-Cigarette and Liquid Nicotine Exposures Among Young Children

E-Cigarette and Liquid Nicotine Exposures Among Young Children

This study has several limitations. Exposure calls to PCCs are voluntary; therefore, the NPDS underestimates the true incidence of exposures to liquid nicotine nationwide. NPDS data may not be representative of the entire spectrum of liquid nicotine exposures because of potential reporting bias. Exposures reported to PCCs do not necessarily represent ingestion, poisonings, or overdoses because exposures are not generally confirmed with definitive laboratory testing. Information provided to PCCs is by self-report, which cannot be completely verified by the PCCs or AAPCC. Differentiation of liquid nicotine exposures due to e-cigarette devices versus e-cigarette liquids
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Ethical considerations of e-cigarette use for tobacco harm reduction

Ethical considerations of e-cigarette use for tobacco harm reduction

The role of tobacco harm reduction in public health Harm reduction policies attempt to diminish the dam- aging effects of a particular behavior without aiming to eliminate the behavior itself. Common applications in- clude the provision of needle exchanges and safe injec- tion kits to injection drug users, and the use of methadone to treat opiate addiction. Despite continued resistance to harm reduction interventions, there is strong evidence demonstrating their successes in public health, most notably in reducing the incidence of HIV and Hepatitis C infection [12–14]. Critics may argue that tobacco harm reduction, as it applies to e-cigarettes, re- mains distinct from harm reduction for other forms of drug addiction. While there is no definitive evidence that either e-cigarettes or needle exchanges promote sub- stance initiation among non-users, critics have expressed concerns about the possibility of a gateway effect of e- cigarettes towards conventional cigarettes [15]. In addition, unlike e-cigarettes, needle exchanges are not backed by powerful political lobbyists or for-profit com- panies [15]. Lastly, injection drug use is comparably in- visible relative to the conspicuousness of using an e- cigarette in public [15]. While these important distinc- tions highlight the need for closer examination, they do not inherently exclude the harm reduction potential of e-cigarettes.
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E-cigarette Use and Subsequent Smoking Frequency Among Adolescents

E-cigarette Use and Subsequent Smoking Frequency Among Adolescents

days), “infrequent users” (use on 1–2 of the past 30 days), or “frequent users” (use on 3–5 or more of the past 30 days). Participants who reported using e-cigarettes, but not cigarettes, in the past 30 days (at baseline or follow-up) were classified as exclusive e-cigarette users; participants who reported using cigarettes, but not e-cigarettes, in the past 30 days were classified as exclusive cigarette users; and participants who reported using both products in the past 30 days were considered dual product users. Sociodemographic Characteristics Questionnaires were also used to assess gender, race/ethnicity (Hispanic, non-Hispanic white, and other), baseline grade in high school (ninth, 10th, 11th, and 12th), and parental education (less than high school, high school graduate, some college, or college graduate; CHS and H&H Study only because this information was not available in the YASS).
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Attitudes toward E Cigarettes, Reasons for Initiating E Cigarette Use, and Changes in Smoking Behavior after Initiation: A Pilot Longitudinal Study of Regular Cigarette Smokers

Attitudes toward E Cigarettes, Reasons for Initiating E Cigarette Use, and Changes in Smoking Behavior after Initiation: A Pilot Longitudinal Study of Regular Cigarette Smokers

This study has some limitations. First, this study was a small pilot study on a small budget that prohibited more elaborate data collection. As such, the small sample size restricts our power. In addition, our weeks 4 and 8 re- tention rates were 83.3% and 72.2%, respectively. Those lost to attrition may have been more likely to have stopped using the e-cigarette or to have continued smoking regular cigarettes. There may also be bias inherent in recruitment through a local e-cigarette vendor, especially given the variety of e-cigarette products on the market. We also did not assess type of e-cigarette purchased; however, our recruitment site—the e-cigarette vendor— indicated that the majority of first-time purchasers of e-cigarettes at this shop purchase the refillable tank style. We also cannot ensure that participants completed the baseline assessments prior to initiating e-cigarette use. However, we recorded the number of days between initial contact to verify eligibility and receipt of the assess- ment; all packets were received in the mail within 8 days. In addition, the sample was drawn from individuals living in one southeastern US state, further limiting its generalizability. Furthermore, future research might ben- efit from a longer follow-up period and additional biomarker assessments (e.g., NNAL). On a related note, ex- posure to secondhand smoke was not assessed and could not be accounted for in the analyses examining predic- tors of salivary cotinine.
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E-cigarettes: a disruptive technology? An analysis of health actors' positions on E-cigarette regulation in Scotland

E-cigarettes: a disruptive technology? An analysis of health actors' positions on E-cigarette regulation in Scotland

In addition to the inconclusive evidence on the harms and benefits of e-cigarettes and the effects that would be expected in case of regulation, views on transnational nicotine and tobacco companies seemed to hinder the development of consensus among health-focused actors. The fact that these companies had become major actors in the e-cigarette market, i.e., in the market of products that some actors perceived as effective quit aids, meant that some actors felt that they needed to re-consider their views about tobacco companies’ engagement in harm reduction, with some concluding that tobacco companies should be treated as legitimate stakeholders. Other actors, however, continued to oppose tobacco industry engagement in health policy and were concerned that e-cigarettes provided the long-sought-after industry opportunity to “address tobacco industry delegitimisation” and “ensure the social acceptability” of tobacco companies [8]. Their underlying views on the need to exclude this industry from e-cigarette debates in order to protect public health took precedence over seeking consensus with other health-focused actors on the appropriate level of e-cigarette regulation. This situation seemed to result in dissent and was in contrast to the previously uniform reluctance of most health-focused organisations to engage with any tobacco industry-affiliated actors [26]. Shifting positions on tobacco industry legitimacy seemed to result in the loss of a sense that tobacco control was united by its common “enemy”, a previously important glue and coalescing force that had held the public health community together in tobacco control debates [7,26,33]. It also meant that dissent evolved within the health community rather than between actors with an interest in health and actors with an economic interest, much as Philip Morris USA had tried to achieve via “Project Sunrise” between 1994 and 2006 [8]. Negative consequences included the disengagement of experts from the debates and the disruption of professional friendships and collaboration, but more importantly, an inability to build advocacy coalitions and jointly lobby on a specific approach to regulation. This helps explain why, although most interviewees positioned themselves as occupying a “middle ground” on e-cigarettes, few felt that the polarised nature of the debates allowed voices from the middle ground to emerge or be heard. Interviewees generally agreed that this was likely to contribute to confusion and uncertainty among public and policy audiences.
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Does Exposure and Receptivity to E-cigarette Advertisements Relate to E-cigarette and Conventional Cigarette Use Behaviors among Youth? Results from Wave 1 of the Population Assessment of Tobacco and Health Study

Does Exposure and Receptivity to E-cigarette Advertisements Relate to E-cigarette and Conventional Cigarette Use Behaviors among Youth? Results from Wave 1 of the Population Assessment of Tobacco and Health Study

used an EC were asked three questions. The first question, “Have you ever been curious about using e-cigarettes?”, had response options on a 4-point scale from “Not at all curious” to “Very curious.” The other two questions, “Do you think that you will try an e-cigarette soon?” and “If one of your best friends were to offer you an e-cigarette, would you use it?”, had response options on a 4-point scale from “Definitely not” to “Definitely yes.” In order to be considered non-susceptible to EC use, participants had to answer “Not at all curious” to the first question and “Definitely not” to the other questions. 27,28 Any other response combination deemed
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The Relation between Frequency of E-Cigarette Use and Frequency and Intensity of Cigarette Smoking among South Korean Adolescents

The Relation between Frequency of E-Cigarette Use and Frequency and Intensity of Cigarette Smoking among South Korean Adolescents

The Korean Youth Risk Behavior Web-Based Survey (KYRBWS) is a nationally representative cross-sectional survey of Korean middle and high school students. The KYRBWS was established in 2005 for assessing health-risk behaviors of adolescents and has provided data for the development and evaluation of school health policies and programs in Korea. The survey was approved by the institutional review board of the Korea Centers for Disease Control and Prevention (2014-06EXP-02-P-A). Written informed consent was received from all participants and their parents or legal guardians. The KYRBWS was described in detail in a previous study [22]. In brief, the KYRBWS data were collected anonymously using a multistage, stratified, cluster-sampling method. The stratification was performed on the basis of 44 provinces and types of schools according to geographic accessibility, the number of schools and population, living environment, smoking rate, and alcohol consumption. The 2015 survey included 70,362 students (ages 13–18 years) in 2400 classrooms (secondary sampling units), which included three classes considering the three year school-term (one class for each year) from each of 400 middle schools and 400 high schools (primary sampling units). Of these, 68,043 adolescents from 797 schools participated in the survey (96.7% response rate). From these participants, we analyzed 6656 adolescents who had an e-cigarette experience. Our study is based on the public use dataset (https://yhs.cdc.go.kr/new/pages/main.asp).
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Passive exposure to e-cigarette emissions: Immediate
respiratory effects

Passive exposure to e-cigarette emissions: Immediate respiratory effects

The current study provides evidence that exposure to SHA from e-cigarettes has immediate effects on respiratory mechanics and exhaled inflammatory biomarkers. These findings add to the growing amount of evidence on the immediate health effects of e-cigarettes. Whereas the clinical implications need further assessment, these findings should be taken into account in global policies regarding the regulation of e-cigarette use in public places and in assessments of the effects of SHA on the health of bystanders.

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Prevalence and predictors of e-cigarette trial among adolescents in Argentina

Prevalence and predictors of e-cigarette trial among adolescents in Argentina

Analyses were conducted using Stata version v13 (Stata Corp, College Station, TX). First, in an attrition analysis, we examined the distribution of the variables to assess differences between students who were and were not followed-up using chi-square and t tests. The dependent variable question described above was used to assess trying e-cigarettes in all students who completed the baseline survey (n=3172) and the follow-up survey (n=2018). To assess the variables that predict new onset of e-cigarette use, we limited the sample for the multivariable analysis to those students who had never tried an e-cigarette at baseline and who had completed both baseline and follow up surveys (i.e., n=1976; 64% follow up). Multilevel logistic regression models with random intercepts for school were used to assess the association between independent variables and new onset of trying e-cigarettes by the follow-up survey. Models were adjusted adding groups of variables that reflected the domains of the conceptual model. To account for potential attrition bias, we estimated weights to apply to each observation in models of e-cigarettes use. Weighting had little effect on most estimates of OR and, as such, we decided to present the non-weighted results.
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Short-term effects of a nicotine-free e-cigarette compared to a traditional cigarette in smokers and non-smokers

Short-term effects of a nicotine-free e-cigarette compared to a traditional cigarette in smokers and non-smokers

The NF e-cigarette used in this study, ELIPS C Series (Ovale Europe S.r.l., Desenzano del Garda, Brescia, Italy), was a brand commercially available in Italy. It was formed of a steel shell with a microprocessor powered by a bat- tery, a filter and a removable cartridge. Among the six dif- ferent types of cartridge available, we chose “Natur Smoke aroma Nocciola Antistress 0 mg/mL nicotina” (Angelica, Bologna, Italy), i.e., a nicotine-free liquid with a hazelnut flavorThe liquid of the cartridge is registered by the Italian Regulatory Agency and had the following composition: glycerin >50 %, isotonic solution 5–10 %, magnesium chloride 1–5 %, natural flavor 0.1–1 %, and vitamin B12 0.1–1 %. The specific kind of NF e-cigarette chosen in the current study followed an unbiased internet search for products available and produced in Italy (e.g.Dea, Flatech, Flavour Roma). Use of the Angelica liquid was finally de- cided mainly due to logistic convenience since it was pro- duced in the same city (Bologna) of investigation.
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Patterns and predictors of e-cigarette, cigarette and dual use uptake in UK adolescents: Evidence from a 24-month prospective study

Patterns and predictors of e-cigarette, cigarette and dual use uptake in UK adolescents: Evidence from a 24-month prospective study

The present research is novel in examining differences between six groups of 15 – 16-year-old adolescents (all of whom neither used cigarettes nor e-cigarettes at 13 – 14 years): never users of cigarettes or e-cigarettes; e- cigarette only users; cigarette only users; dual users — order of fi rst use unclear; dual users — e-cigarettes used fi rst; and dual users — cigarettes used fi rst. Previous reports of the current data focused on examining how e-cigarette use as a 13 – 14-year-old predicted progression to cigarette smoking at age 14 – 15 years [10] or 15 – 16 years [17]. The present research tested differences among these six groups. Our aims were to: (1) estimate the numbers in each of the six groups; (2) test differences in the rates of regular cigarette smoking among the four smoking groups (i.e. cigarette only users; dual users — order of fi rst use un- clear; dual users — e-cigarettes used fi rst; dual users — ciga- rettes used fi rst); (3) test differences in the rates of regular e-cigarette use among the four e-cigarette groups (i.e. e- cigarette only users; dual users — order of fi rst use unclear; dual users — e-cigarettes used fi rst; dual users — cigarettes used fi rst); and (4) identify the predictors of being in one of the fi ve user groups (i.e. e-cigarette only users; cigarette only users; dual users — order of fi rst use unclear; dual users — e-cigarettes used fi rst; dual users — cigarettes used fi rst) compared to the never user group. The research pro- vides insights into the determinants and consequences of different patterns of adolescent use of cigarettes and e- cigarettes. The former might be useful in generating targeted interventions to reduce smoking initiation in dif- ferent groups of adolescents, while the latter might be use- ful in deciding on which groups to target with interventions.
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Epiglottitis Associated With Intermittent E-cigarette Use: The Vagaries of Vaping Toxicity

Epiglottitis Associated With Intermittent E-cigarette Use: The Vagaries of Vaping Toxicity

smokers, after 5 minutes, e-cigarette use increased airway resistance and decreased fractional exhaled nitric oxide. 27 An adolescent study found potentially carcinogenic compounds in the urine of e-cigarette users. 28 It is reasonable to suspect that there is potential for allergenicity as well, although little direct research has been published on that topic. In an adolescent with signs and symptoms of subacute epiglottis, the differential should expand beyond infectious etiologies. E-cigarettes are increasingly being used by our adolescent patients and should be a consideration in the evaluation of ororespiratory complaints.
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Patterns and predictors of e-cigarette, cigarette and dual use uptake in UK adolescents: : Evidence from a 24-month Prospective Study

Patterns and predictors of e-cigarette, cigarette and dual use uptake in UK adolescents: : Evidence from a 24-month Prospective Study

friends to assess their influence on e-cigarette/cigarette use compared to non-users. Fifth, we did not ask about age at which cigarette and/or e-cigarette use began thus precluding any consideration of duration. Sixth, it is possible that the many dual users could not accurately recall whether they use cigarettes or e-cigarettes first, which increases the uncertainty of the findings. It could be that this ‘unsure’ group is distinct and first used cigarettes and e-cigarettes at a similar point in time or that they more accurately belong in one of the dual user – cigarettes used first or dual user – e- cigarettes used first groups. Finally our research had a limited geographical (two English counties) and age (baseline: 13-14 years) distribution and did not control for the clustering of the data by school (schools level randomisation to intervention and control conditions). Nevertheless, there are no strong reasons to suspect that any of these factors would have substantially altered the findings reported. Future studies might address some of these issues and explore effects in different aged adolescents and over varying time periods.
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E cigarette marketing in UK stores : an observational audit and retailers' views

E cigarette marketing in UK stores : an observational audit and retailers' views

Regardless of the future of the e-cigarette, be it as an effective cessation tool or potential contributor to health harm, in the immediate term this study fl ags up several areas worthy of more detailed investigation. E-cigarette marketing in the form of purpose-designed displays and range of brands stocked is proliferating at the same time that in-store cigarette advertising and display has been prohibited in the UK. Given that some e-cigarette adver- tising borrows from the language and imagery previously used in tobacco marketing, and that some products are modelled on conventional cigarettes, 20 this may under- mine the ban on tobacco advertising, at least until 2016, by reintroducing tobacco imagery and cues into a space where they have just been removed through the POS ban. This requires ongoing scrutiny, particularly as the covering up of tobacco products could result in e- cigarettes and their marketing becoming even more visible and prominent.
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Patterns and predictors of e-cigarette, cigarette and dual use uptake in UK adolescents: : Evidence from a 24-month Prospective Study

Patterns and predictors of e-cigarette, cigarette and dual use uptake in UK adolescents: : Evidence from a 24-month Prospective Study

they contain nicotine). Thirdly, our research did not in- clude measures of perceptions of e-cigarettes shown to pre- dict e-cigarette and dual use [12 – 16]. Fourthly, we did not ask about e-cigarette use among family and friends to as- sess their in fl uence on e-cigarette/cigarette use compared to non-users. Fifthly, we did not ask about age at which cig- arette and/or e-cigarette use began thus precluding any consideration of duration. Sixthly, it is possible that the many dual users could not accurately recall whether they used cigarettes or e-cigarettes fi rst, which increases the un- certainty of the fi ndings. It could be that this ‘ unsure ’ group is distinct and fi rst used cigarettes and e-cigarettes at a similar point in time or that they more accurately be- long in one of the dual user — cigarettes used fi rst or dual user — e-cigarettes used fi rst groups. Finally, our research had a limited geographical (two English counties) and age (baseline: 13 – 14 years) distribution and did not control for the clustering of the data by school (schools-level ran- domization to intervention and control conditions). Never- theless, there are no strong reasons to suspect that any of these factors would have substantially altered the fi ndings reported. Future studies might address some of these issues and explore effects in different aged adolescents and over varying time-periods.
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Compensatory Puffing With Lower Nicotine Concentration E liquids Increases Carbonyl Exposure in E cigarette Aerosols

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

The human puffing topography data was taken from Dawkins et al. (2016). In two separate sessions, 12 experienced vapers were asked to use a ‘Joyetech eVic Supreme’ e-cigarette (output voltage fixed at 3.9 V equipped with an “Aspire Nautilus” tank set to the largest airflow housing a BVC atomiser with a resistance of 1.8 Ohm resulting in a power of 8.5W) ad libitum for 60 min. All participants were daily e-cigarette users and had used for more than 3 months, were currently using a tank-style device, familiar with 24 mg/mL nicotine concentration liquid (i.e. used 24 mg/mL at least once in the last 6 months), used a mean of 11 mg e-liquid per day and had a baseline salivary cotinine level > 100 ng/mL. Participants were 12 h nicotine abstinent (as confirmed by blood nicotine levels measured at the start of the session). Using a double-blind counterbalanced design, participants were administered a high (24 mg/mL) and low (6 mg/mL) nicotine concentration on two separate days. Puffing topography (puff number and puff duration) was recorded by the eVic™ and downloaded to ‘My Vapors Joyetech 1.4’ (See Dawkins et al, 2016 for the full protocol).
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E-cigarette use in Canada: prevalence and patterns of use in a regulated market

E-cigarette use in Canada: prevalence and patterns of use in a regulated market

Consistent with previous studies, younger smokers were more likely to use e-cigarettes than older smokers. 9 Males were also more likely to use e-cigarettes compared to females, although no differences were observed across education levels, in contrast to previous data sug- gesting higher rates of use among more educated groups. 20 Dual use of tobacco cigarettes and e-cigarettes was reported in the current study. Approximately 13% of smokers currently used e-cigarettes, which is similar to previous estimates that reported between 12% and 34% of dual use. 11 A majority of participants reported using a tobacco cigarette fi rst; however, there was evidence of participants trying an e-cigarette before ever using a tobacco cigarette. It is important to note that the current data regarding individuals who tried an e-cigarette before a tobacco cigarette does not necessar- ily constitute evidence of a ‘ gateway ’ effect. As discussed elsewhere, this temporal order could be due to common causes with respect to risk-taking predisposition or envir- onmental and social in fl uences, including easier access to e-cigarettes. 21
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Application of dosimetry tools for the assessment of e-cigarette aerosol and cigarette smoke generated on two different in vitro exposure systems

Application of dosimetry tools for the assessment of e-cigarette aerosol and cigarette smoke generated on two different in vitro exposure systems

at very high dilutions. This could be device and/or e-liq- uid specific and needs further investigation. Assessing different product aerosols within different exposure sys- tems highlights the importance of dosimetric characteri- sation. These exposure systems were originally designed for use with combustible products in mind. For e-ciga- rette aerosols, noteworthy differences to cigarette smoke in such systems include visibly wetter aerosols condens- ing in transit tubing (possibly restricting aerosol flow and impeding syringe function) and some concerns with device button activation synchrony (either manually, or automated with a separate robot) with the syringe puff- ing to ensure the entire puff is activated and delivered. It is important to be aware of issues such as consistency of device activation and puffing as it will affect dose. A lot of these observations will also change depending on e-cigarette device type/design, e-liquid composition, device battery power and activation voltage, coil resist- ance, exposure system, transit tubing length and so on. Thus it is crucial to understand each unique set-up and test article prior to in  vitro biological exposure. With applied dosimetry, such differences between systems, test articles, cell types and exposure duration become less relevant when biological responses can be presented and aligned against a common dose metric. The differ- ences we observed in delivery between the two exposure systems are likely due to their engineering and dilution mechanisms (Table 1) as we have shown that generation at source was consistent between systems for the same product. The VC 10 demonstrated greater values for deposited mass (and thus nicotine concentration) (Fig. 7) and also greater ratio differences between products com- pared to the RM20S, however their transit lengths from generation to exposure differ too, with the VC 10 being shorter than the RM20S, at 90 and 290 cm respectively. In addition, not only flow rate, but also droplet diame- ter, diffusion, and gravitational settling play a significant role in the process of aerosol deposition in the Vitrocell ® exposure module [25]. Despite these system differences, there was an apparent dose range overlap where 1:5 and 1:10 on the RM20S were approximate to 0.5 and 1.0 L/ min on the VC 10, respectively (Figs. 5, 6). These obser- vations can assist when comparing varied biological response data from our two systems. This approach will become even more important when comparing reported data from an ever varied source of test articles, biologi- cal endpoints and exposure systems: dosimetry tech- niques will be able to unite data and systems with diverse modes of dilution.
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