Sources of exposure to non-tobacco nicotine electronic nicotine delivery systems and associations with susceptibility to use and use behaviors among young adults in the United States.

INTRODUCTION: The Electronic Nicotine Delivery Systems (ENDS) industry recently introduced non-tobacco nicotine (NTN), which is not tobacco-derived and is often marketed as "tobacco-free nicotine." Given its novelty, it is important to understand where young adults learn about NTN ENDS. This study examined sources of exposure to NTN ENDS and relationships with NTN ENDS use and susceptibility. METHODS: We analyzed online survey data collected in Fall 2021 from 642 young adults (18-25 years) who had heard of NTN ENDS. We assessed 9 sources of NTN ENDS exposure (e.g., retail stores, social media) and examined associations between sources of exposure and NTN current (past-month) use, lifetime (non-current) use, and susceptibility to use, adjusting for demographics and other tobacco product use. RESULTS: Participants reported current NTN ENDS use (37.4%), lifetime use (12.0%), susceptibility (18.5%), or no susceptibility to use (32.1%). The most common sources of NTN ENDS exposure were retail stores (87.7%) and social media (81.0%). Exposure to NTN ENDS via social media was associated with greater odds of current NTN ENDS use (vs. no susceptibility) (aOR = 1.83, 95%CI: 1.02-3.28). Exposure via online streaming platforms was associated with greater odds of current (aOR = 1.75, 95%CI: 1.08-2.82) and lifetime NTN ENDS use (aOR = 2.42, 95%CI: 1.25-4.68). CONCLUSIONS: Young adults were exposed to and learned about NTN ENDS from diverse sources, primarily retail shops and social media. Further, exposure via social media and streaming platforms were associated with NTN ENDS use. Future studies should explore the content of NTN information from various sources to inform prevention efforts.

Cardiovascular Health Effects and Synthetic Cooling Agents in E-cigarettes Labeled as 'clear' Marketed in Massachusetts After the Tobacco Product Flavoring Ban.

Introduction: Massachusetts (MA) enacted statewide regulation on all flavored tobacco products in June 2020. Thereafter, electronic cigarettes (e-cigarettes) labeled 'clear' emerged on the market. We aimed to combine cardiovascular health effects with chemical analysis of 'clear' e-cigarettes. Methods: We measured acute changes in blood pressure and heart rate following a 10-minute structured use of participants' own e-cigarette, comparing 'clear' e-cigarette users with other flavored e-cigarette users and non-users. Chemical characterization and quantification of relevant flavorings and cooling agents (WS-3, WS-23) of 19 'clear'-labeled disposable e-cigarette liquids was carried out by GC/MS. Results: After the ban, participants that used 'clear' labeled e-cigarettes increased from 0% to 21%. Increase in diastolic blood pressure and heart rate was significantly greater in 'clear' e-cigarettes users (n=22) compared to both non-'clear' flavored e-cigarette users (n=114) and non-users (n=72). We saw similar results in heart rate when comparing Juul e-cigarette and 'clear' users; Juul was used as a reference as synthetic coolants WS-3 or WS-23 were not detected in these.All (19/19) 'clear' e-liquids were found to contain synthetic cooling agents WS-23 and/or WS-3, menthol (18/19), as well as other flavorings (12/19). Discussion: The detected presence of menthol alongside other flavorings in tested 'clear' products is a direct violation of the MA flavored tobacco product regulation, warranting stricter monitoring for new products and constituents. 'clear' e-cigarette use led to greater hemodynamic effects compared to other flavored e-cigarettes and Juul, which raises questions about the effect of cooling agents on users.

E-cigarette dependence and cooling flavor use are linked among youth.

BACKGROUND: E-cigarette flavors that produce cooling sensations may reduce nicotine harshness and enhance appeal among youth. While previous research has shown that use of cooling flavors is associated with more frequent vaping among youth, it is unknown whether the same holds true for e-cigarette dependence. This study examines the relationship between cooling flavor use and e-cigarette dependence among youth accounting for vaping frequency. METHODS: In Fall 2022, a survey was conducted among Connecticut high school students to assess past-month nicotine e-cigarette use, ever use of cooling flavors, cooling flavor types (e.g., fruit-cooling), and e-cigarette dependence. Analyses were restricted to those with past-month nicotine and nicotine-free e-cigarette use and complete data (n=204). Multivariable linear regressions were run to examine the association between cooling flavor use and e-cigarette dependence, adjusting for demographics, e-cigarette use characteristics, and other tobacco product use. RESULTS: 78.4% of the sample used cooling e-cigarette flavors, with 55.0% using mint-cooling flavors and 52.5% using fruit-cooling flavors. Regression results observed that cooling flavor use was associated with higher e-cigarette dependence (ꞵ=1.53, SE=0.63, p=0.017), with those who used cooling flavors having higher e-cigarette dependence than those who did not (M=5.78 [SD=5.33] vs. 2.84 [3.19]). CONCLUSIONS: Our results suggest that cooling flavor use is significantly associated with e-cigarette dependence among youth. While regulations often target menthol flavor, tobacco control agencies should consider restricting any flavor that can produce cooling sensations, even if they are not traditional menthol products, as cooling flavors is associated with youth e-cigarette dependence.

Non-tobacco nicotine E-cigarette use and flavored E-cigarette use among young adults in the United States.

BACKGROUND: E-cigarette flavors can create sensations of sweetness and coolness while masking the aversiveness of nicotine. Recently, non-tobacco nicotine (NTN) products were introduced to the market, but little is known about flavors in NTN e-cigarette use. We examined associations between flavors (i.e., sweet, mint/menthol) and susceptibility to and use of NTN e-cigarettes. METHODS: 1239 US young adults (18-25 years) completed an anonymous, online survey in Fall 2021. The analytic sample included 520 participants who had used e-cigarettes and heard of NTN. Multinomial logistic regression models analyzed associations of flavored e-cigarette use (sweet and mint/menthol) with NTN e-cigarette use status (i.e., current [past-month] use, past [ever but not current] use, susceptible to use, and non-susceptible to use [reference]). RESULTS: Overall, 46.2% of participants reported current NTN use, 14.8% reported past use, 16.7% were susceptible to use, and 22.3% reported no susceptibility. Participants reported dual-use of sweet and mint/menthol NTN e-cigarette flavors (56.5%), sweet flavors use (24.8%), and mint/menthol flavor use (1.7%). Ever dual use of sweet and mint/menthol flavors was associated with current (OR = 9.64, 95%CI: 3.21-28.98) and past NTN e-cigarette use (8.30, [2.10-32.80]). Ever sweet flavor use was associated with current NTN use (3.80, 95%CI: 1.44-10.03) and susceptibility to future use (4.25, [1.53-11.81]). Similar findings were observed for mint/menthol flavors (current: 5.03, [1.41-17.99]; susceptible: 5.65, [1.64-19.51]). CONCLUSION: The use of sweet and mint/menthol flavors was significantly associated with NTN e-cigarette use among US young adults, highlighting the need for ongoing surveillance of flavored NTN e-cigarettes and appropriate regulations to discourage use.

Changes in weight among individuals with psychiatric conditions or socioeconomic disadvantage assigned to smoke very low nicotine content cigarettes.

Nicotine abstinence leads to weight gain, which could be an unintended consequence of a nicotine reduction policy. This secondary analysis used weekly assessments of weight and ratings of "increased appetite/hunger/weight gain" collected in three 12-week, randomized controlled trials evaluating the effects of cigarettes differing in nicotine dose (15.8, 2.4, or 0.4 mg/g) among individuals with affective disorders, opioid use disorder (OUD), and socioeconomically disadvantaged women. Linear mixed models tested differences by dose and time. Analyses first collapsed across populations and then separated out individuals with OUD because biomarkers suggested they used substantially more noncombusted nicotine. Across populations, weight increased significantly over time, averaging 1.03 kg (p < .001), but did not vary by dose nor was there any interaction of dose/time. "Increased appetite/hunger/weight gain" ratings increased significantly as a function of dose, with differences between low and high doses (1.95 and 1.73, respectively, p = .01), but not by time nor any interaction. In the combined group of individuals with affective disorders and socioeconomically disadvantaged women, weight and "increased appetite/hunger/weight gain" ratings increased significantly by dose, with differences between low and high doses (1.43 vs. 0.73 kg, p = .003 and 2.00 vs. 1.76, p = .02, respectively). Among individuals with OUD, there were no significant effects of any kind on either outcome. Individuals with affective disorders and socioeconomically disadvantaged women gained weight and reported more subjective appetite/weight gain when given 0.4, but not 2.4 mg/g cigarettes, despite comparable decreases in nicotine exposure. However, neither change was clinically significant, suggesting minimal short-term adverse consequences of a nicotine reduction policy. (PsycInfo Database Record (c) 2024 APA, all rights reserved).

Why young adults use tobacco-free nicotine E-cigarettes: An analysis of qualitative data.

BACKGROUND: Tobacco-free nicotine (TFN) is often marketed as being better tasting and healthier than tobacco-derived nicotine (TDN). Studies have yet to systematically characterize subjective experiences using TFN e-cigarettes. This qualitative study explored young adults' reasons for using TFN e-cigarettes and perceptions of differences between using TFN and TDN e-cigarettes. METHOD: We conducted a national online Qualtrics survey of U.S. young adults aged 18-25 years in October 2021. Respondents who reported lifetime TFN e-cigarette use (n = 317, mean age: 20.8 (SD:2.2), 53.9 % female) provided write-in responses to open-ended questions assessing reasons for using TFN e-cigarettes and perceptions of differences between TFN and TDN e-cigarettes. Responses from participants were thematically analyzed by independent raters. RESULTS: Reasons for using TFN e-cigarettes included product taste/flavor, health reasons (e.g. believing TFN was healthy), and product accessibility. Perceptions of differences between TFN and TDN e-cigarettes included differences in taste/ flavor and acute psychoactive and physical effects (e.g., nicotine buzz, throat hit), with TFN e-cigarettes being described as generally stronger and superior relative to TDN e-cigarettes. CONCLUSION: These qualitative data suggest that taste and perceived health benefits are primary reasons that young adults try TFN e-cigarettes. Compared to TDN, young adults perceive TFN as better tasting with different psychoactive and less aversive effects. Determining if these perceived reasons for use and differences occur in blinded human experimental studies is a necessary next step to understanding TFN e-cigarette use. Additionally, understanding why young adults use TFN e-cigarettes is important in the development of prevention communication about these products.

Psychometric evaluation of the sensory e-cigarette expectancies scale for use with adolescents.

BACKGROUND: The Sensory E-cigarette Expectancies Scale (SEES) has demonstrated solid psychometric properties for use with adults. It assesses expectancies for enjoying the taste and smell of vaping, experiencing pleasurable physical sensations, and enjoying creating vapor clouds. We evaluated psychometric properties of the SEES for use with adolescents. METHODS: In Fall 2022, 4,855 students from eight Connecticut high schools completed an anonymous, cross-sectional, online survey. Our analytic sample (n = 724) endorsed lifetime e-cigarette use and completed the SEES. Psychometric analyses included factor analyses, internal reliability, measurement invariance, between-groups differences, and relationships with vaping outcomes. RESULTS: The three-factor SEES structure was confirmed. Internal reliability of each subscale was excellent (range: 0.88-0.95). The SEES was invariant by sex (male/female), race (Black/White/Other), Hispanic ethnicity (no/yes), nicotine e-cigarette use (no/yes), any past-month vaping (no/yes), daily vaping (no/yes), and vaping status (a variable created based on the distribution of past-month vaping frequency [0; 1-4; 5-20; 21+ days]). Those who reported using nicotine e-cigarettes, past-month vaping, daily vaping, and vaping on 21+ days in the past month reported stronger scores on each subscale compared to their respective counterparts. In adjusted models, expecting Pleasurable Physical Sensations was associated with total flavors used, past-month vaping frequency, and e-cigarette dependence. Enjoyment of Taste and Smell was positively associated with total flavors used and e-cigarette dependence. Enjoyment of Vapor Clouds was positively associated with total flavors used and past-month vaping frequency. CONCLUSIONS: Given its strong psychometric properties, the SEES can be used in future research to assess sensory-related vaping expectancies in youth.

Accurately classifying cannabis blunt use as tobacco-cannabis co-use versus exclusive cannabis use.

BACKGROUND: Historically, blunt use constituted tobacco-cannabis co-use based on the products available for creating blunts (e.g., hollowed-out cigars filled with cannabis). With the introduction of tobacco-free blunt wraps (e.g., hemp wraps), blunt use now may constitute tobacco-cannabis co-use or exclusive cannabis use. We examined adolescents' use of tobacco and tobacco-free blunt products and highlighted how misclassification of tobacco-cannabis co-use versus exclusive cannabis use may occur if products used to make blunts are not assessed. METHODS: 4855 students from eight Connecticut high schools completed an online survey in 2022. Use of tobacco products for making blunts (e.g., cigarillos, tobacco blunt wraps) and tobacco-free blunt wraps were assessed as was the use of other tobacco products (e.g., e-cigarettes, cigarettes, hookah). The analytic sample comprised 475 students who endorsed lifetime blunt use. RESULTS: Tobacco-free blunt wraps (72.6%) were the most popular product for making blunts, followed by cigarillos (56.5%), tobacco blunt wraps (49.2%), and large cigars (13.0%). When classified into mutually exclusive groups, students reported exclusive tobacco-free blunt use (32.3%), exclusive tobacco product blunt use (27.4%), or use of both tobacco product and tobacco-free blunts (40.3%). Among those exclusively using tobacco-free blunts, 13.4% endorsed no tobacco product use. CONCLUSIONS: Tobacco-free blunt wraps were very popular among high school adolescents, highlighting the importance of assessing products used for making blunts. Assuming that blunts contain tobacco without considering tobacco-free blunts can lead to misclassification of blunt use as tobacco-cannabis co-use when it actually reflects exclusive cannabis use, potentially leading to inflated estimates of tobacco use. DATA AVAILABILITY: Data will be made available upon reasonable request to the corresponding author.

Considerations of Sex and Gender in FDA Tobacco Regulation.

This Viewpoint discusses how sex and gender subpopulations may be differentially affected by tobacco products and suggests that the FDA formulate regulations in clinically meaningful ways.

Reactions to using other nicotine and tobacco products instead of menthol cigarettes: A qualitative study of people who smoke menthol cigarettes in the United States.

The US Food and Drug Administration is considering banning menthol cigarettes, which could result in some people who smoke menthol cigarettes switching to other tobacco products (OTPs). This qualitative study explored reactions to using OTPs instead of menthol cigarettes. People who smoke menthol cigarettes (N=40) completed a behavioral economic assessment of the effects of menthol cigarette price increases on OTP purchasing. At the highest price, most participants could not afford menthol cigarettes. Instead, they could purchase non-menthol cigarettes, little cigars/cigarillos (LCCs), e-cigarettes, smokeless tobacco, or medicinal nicotine, or they could abstain from tobacco use. Participants used the OTPs they purchased for three days. During follow-up sessions, participants (n=35) completed semi-structured interviews discussing their purchasing-decisions and experiences using OTPs instead of menthol cigarettes. Interviews were analyzed using reflexive thematic analysis methods. Factors influencing purchasing decisions included flavor, price, prior use of OTPs, interest in trying new OTPs, and perceived ability to satisfy nicotine cravings. Participants described positive experiences using e-cigarettes including the "refreshing" menthol flavor, ability to use in places where cigarettes are prohibited, and convenience of use relative to smoking. Among those using non-menthol cigarettes, many reported they were acceptable but less satisfying products compared to menthol cigarettes while others reported negative reactions to them such as tasting like "cardboard". Reactions to smoking LCCs were mostly unfavorable but participants said it gave them "something to light". Multiple considerations may affect switching to OTPs in light of pending menthol cigarette regulation including the availability of menthol-flavored alternatives and (dis)satisfaction with OTPs.

The first nicotine product tried is associated with current multiple nicotine product use and nicotine dependence among a nationally representative sample of U.S. youths.

This study examines the demographic factors associated with youths' first product tried (i.e., cigarettes, e-cigarettes, cigars, hookah, or smokeless tobacco). This study also evaluates whether the first product tried is associated with future nicotine product use (i.e., no use, single product use, and multiple product use) and nicotine dependence. Participants were 1999 youths (ages 12-17 years) who had ever tried a nicotine product and completed the Population Assessment of Tobacco Health study's Wave 1 (2013-2014) and Wave 4 (2016-2018) assessments. Two separate multinomial logistic regression models examined the association between 1) demographic factors and the first product tried at Wave 1 and 2) the first product tried at Wave 1 and past-30-day product use status at Wave 4. A two-part multivariable model examined the association between the first product tried and nicotine dependence, with part 1 modeling the presence (or absence) of any symptom of dependence and part 2 modeling the degree of dependence among those with any symptom of dependence. The first product tried was associated with sex, race, urbanicity, and parent education. First trying smokeless tobacco (vs. e-cigarettes) was associated with a greater likelihood of multiple product use (vs. no use and vs. single product use). Regarding the degree of nicotine dependence (n = 713), first trying smokeless tobacco (vs. e-cigarettes) was associated with higher nicotine dependence scores among those with any symptom of dependence. Youths who first try smokeless tobacco (vs. e-cigarettes) may be at higher risk for future multiple product use and more symptoms nicotine dependence. Research should explore tailored interventions for smokeless tobacco users.

Awareness, susceptibility, and use of oral nicotine pouches and comparative risk perceptions with smokeless tobacco among young adults in the United States.

BACKGROUND: Oral nicotine pouches (NPs) that contain nicotine but no tobacco leaves are rapidly gaining popularity. However, there is limited research on NPs, including within priority populations. In the current study, we examined awareness of, susceptibility to, and use of NPs in young adults as well as comparative risk perceptions with smokeless tobacco. METHODS: In 2021, 609 young adults (18-25 years) completed an online survey. Participants reported on NP awareness, susceptibility, and use as well as on comparative product perceptions for NPs versus smokeless tobacco. We ran unadjusted between-groups comparisons and an adjusted multinomial logistic regression to identify relationships between product perceptions and NP susceptibility and use. RESULTS: 41.5% of participants had heard of NPs before. Participants were non-susceptible (66.2%), susceptible (23.5%), or had used NPs (10.3%). Comparative product perceptions between NPs and smokeless tobacco suggested that young adults, as a whole, expressed uncertainty about the relative risk/benefit of using NPs versus smokeless tobacco. However, as expected, unadjusted and adjusted findings indicated that favorable perceptions of NPs versus smokeless tobacco were disproportionately observed among susceptible participants and NP users compared to non-susceptible individuals. Demographic differences were also observed (e.g., NP users were more likely than non-susceptible and susceptible individuals to have used smokeless tobacco). CONCLUSIONS: Young adults reported awareness of, susceptibility to, and use of NPs, with findings indicating that favorable perceptions of NPs versus smokeless tobacco may contribute to NP susceptibility and use beyond known correlates like smokeless tobacco use. However, further research is needed to understand the full range of factors that are associated with NP susceptibility and use. It will be important to disentangle factors that are associated with potential positive public health impacts (e.g., switching from smokeless tobacco to exclusive NP use) from those associated with negative public health impacts (e.g., initiation among nicotine naïve individuals).

"Tobacco-free" Nicotine Pouches: Risk Perceptions, Awareness, Susceptibility, and Use Among Young Adults in the United States.

BACKGROUND: Nicotine pouches containing synthetic nicotine or tobacco-derived nicotine (TDN) are available in the United States. Synthetic nicotine pouches are often marketed as "tobacco-free nicotine" (TFN), which may alter risk perceptions and product appeal. This study examined young adults' perceptions of TFN versus TDN pouches and the associations between product perceptions and TFN pouch awareness, susceptibility, and use, respectively. AIMS AND METHODS: In total 630 young adults (18-25 years) completed an online Qualtrics panels survey in 2021. Participants were informed that TFN pouches contain synthetic nicotine as opposed to TDN. Participants reported on comparative risk perceptions for TFN versus TDN pouches and on TFN pouch awareness, susceptibility, and use. Unadjusted between-group comparisons and adjusted binary logistic regressions were run to examine relationships between product perceptions and TFN pouch awareness, susceptibility, and use. RESULTS: Participants were aware of (37.3%), susceptible to (29.2%), or had used TFN pouches (3.8%). In unadjusted comparisons, TFN pouch awareness, susceptibility, and use were associated with disproportionately perceiving TFN pouches as less harmful or otherwise better than TDN pouches. In adjusted models, relationships between favorable perceptions and both TFN pouch awareness and susceptibility remained significant. CONCLUSIONS: The descriptor "tobacco-free" may impact risk perceptions and the appeal of nicotine pouches among young adults. While no direct relationship was observed between TFN perceptions and TFN pouch use in the adjusted model, perceptions remained related to product awareness and susceptibility, which may be linked to future use. Continued surveillance is needed to fully determine how the term "tobacco-free" on product packaging and advertising impacts longitudinal public health outcomes. IMPLICATIONS: Nicotine pouches originally contained TDN. Today, numerous brands of synthetic nicotine pouches, which are often marketed as "tobacco-free," are available on the market. We informed participants that "tobacco-free nicotine" pouches contain synthetic nicotine and examined comparative risk perceptions (i.e. tobacco-free vs. TDN pouches) and TFN pouch awareness, susceptibility, and use. Perceiving tobacco-free nicotine pouches as less harmful than tobacco-derived pouches was associated with product awareness, susceptibility, and use in unadjusted models and with awareness and susceptibility in adjusted models. Restricting the term "tobacco-free" may become necessary if the term inaccurately reduces product risk perceptions or increases product appeal.

Use and Product Characteristics of "Tobacco Free Nicotine" E-Cigarettes Among Young Adults.

INTRODUCTION: E-cigarettes are increasingly being marketed as containing tobacco-free nicotine (TFN). There is no data examining use of TFN e-cigarettes by young adults and how use may differ from non-TFN e-cigarettes. The current study aims to characterize young adult TFN e-cigarette use and examine differences between those who report using TFN and non-TFN e-cigarettes. METHOD: U.S. young adults (18-25) with lifetime e-cigarette use (n = 927) were recruited via online panels in Fall 2021 and answered questions about TFN and non-TFN e-cigarettes. Participants were categorized by lifetime TFN e-cigarette use status (yes vs. no; 34% yes). Bivariate comparisons examined differences in e-cigarette characteristics (device type, flavors, nicotine concentration) between the TFN and non-TFN groups. Binary logistic regression models examined associations between lifetime frequency of vaping (<100 vs. ≥100 times), and other tobacco product, cannabis, and/or alcohol use and lifetime TFN e-cigarette use (yes vs. no). Adjusted models include age, race/ethnicity, vaping onset age, and sex. RESULTS: In multivariable adjusted models, lifetime TFN e-cigarette use was associated with younger age, greater lifetime vaping, and nicotine pouch use. Young adults who used TFN e-cigarettes were more likely to report fruit, mint, menthol, and beverage flavors and know their e-liquid nicotine concentration compared with those who used non-TFN e-cigarettes. CONCLUSION: Among young adults who have used e-cigarettes, more frequent e-cigarette use and use of nicotine pouches, which can also contain TFN, were associated with TFN e-cigarette use. Understanding behaviors and characteristics of those using TFN e-cigarettes is critical to regulation of TFN containing products. IMPLICATIONS: This study characterizes young adults who report experience with tobacco free nicotine (TFN) e-cigarettes and compares them to those who have not used TFN e-cigarettes. Young adults with more frequent e-cigarette use and use of nicotine pouches are more likely to report TFN e-cigarette use.

Relating individual differences in the reinforcing value of smoking and dependence severity to nicotine exposure levels in vulnerable populations.

Cigarette smoking is overrepresented in populations with psychiatric conditions and socioeconomic disadvantage. Greater understanding of the role of reinforcement and nicotine dependence in smoking among vulnerable populations may facilitate development of better targeted interventions to reduce smoking. Prior research demonstrated that individual differences in the reinforcing value of smoking and nicotine-dependence severity predicted total nicotine-exposure in vulnerable populations. The present study uses multivariate regression to address two aims: (1) Quantify the degree to which the reinforcing value of smoking, assessed using the Cigarette Purchase Task (CPT), and dependence severity assessed using the Fagerström Test of Nicotine Dependence and Brief Wisconsin Inventory of Smoking Dependence Motives (B-WISDM) each account for individual differences in cotinine-plus-3'-hydroxycotinine (COT+3HC) levels. (2) Explore whether there is overlap in the variance accounted for by the CTP, FTND, and B-WISDM. Participants were 628 adults with co-morbid psychiatric conditions or socioeconomic disadvantage who smoked daily. The CPT, FTND, and B-WISDM models accounted for 23.76%, 32.45%, and 29.61% of the variance in COT+3HC levels, respectively. Adding CPT to the FTND model failed to increase the variance accounted for and adding it to the B-WISDM model did so by only 1.2% demonstrating considerable overlap in the variance in nicotine exposure levels accounted for by these three instruments. These results provide new knowledge on the relationship between individual differences in the reinforcing value of smoking and nicotine-exposure levels and suggest differences in reinforcing value may underpin a considerable portion of the variance in nicotine exposure accounted for by dependence severity.

Curiosity, use, and perceptions of "tobacco-free nicotine" E-cigarettes among U.S. young adults.

This study determined whether young adults perceptions of how tobacco free nicotine (TFN) compared to tobacco-derived nicotine (TDN) were associated with curiosity to try or use TFN e-cigarettes. U.S. young adults aged 18-25 years (n = 1176) completed an online survey in October 2021. Survey questions assessed TFN awareness, curiosity, use, and perceptions of how flavor, taste, ease of access, cost, and harm compared between TFN and TDN. Participants were categorized into 3 groups: not curious to try TFN (n = 511, 43.5%), curious to try TFN (n = 348, 29.6%), and ever used TFN (n = 317, 27%). Multinomial logistic regression measured associations between perceptions and TFN curiosity and use (vs. not curious to try), with total number tobacco products used and demographics as covariates. Compared to young adults who were not curious to try TFN e-cigarettes, those who were curious perceived TFN as less addictive than TDN (aOR = 2.27; 95% CI =1.34-3.86). Those who had used TFN e-cigarettes perceived TFN as having flavors that tasted better (aOR = 1.80; 95% CI = 1.63-1.99), "smoother" (aOR = 1.88; 95% CI =1.18-2.99), and less like tobacco (aOR 1.94; 95% CI 1.23-3.05). Adjusted models did not show differences in perceptions between those who had tried TFN and those who were curious to try TFN. Young adults who were curious to try or had used TFN had more positive perceptions of TFN. As it is currently unclear whether synthetic nicotine carries the same health risks as TDN, ongoing surveillance of TFN uptake among young adults is warranted.

Association of youth impulsivity and use of e-cigarette devices, flavors, and frequency of use.

INTRODUCTION: Given high youth e-cigarette use, it is important to investigate how traits, like impulsivity, may be associated with youth e-cigarette use behaviors. The study aim is to determine if impulsivity is associated with trying more e-cigarette flavors and device types, and greater frequency of e-cigarette use. METHOD: Cross sectional survey data from CT high schoolers (n = 4875, 6 schools) were collected in 2019. Lifetime (ever) e-cigarette users (n = 2313) completed the Brief Barrett Impulsivity Scale, which contains two subscales; behavioral impulsivity and impaired self-control. Among lifetime users, associations between impulsivity subscales and number of e-cigarette flavors tried, e-cigarette devices tried, and past 30-day frequency of e-cigarette use were examined using regression models. Additionally, associations of impulsivity and use frequency were examined among only current e-cigarette users (≥1 day of use in past 30; n = 1327). School, age, race/ethnicity, vaping initiation age, other tobacco product use, and sex were included as covariates in models. RESULTS: Higher behavioral impulsivity was associated with greater number of e-cigarette flavors tried (AOR: 1.06, 95% CI: 1.02, 1.11, p <.008) and higher frequency of past 30-day use both among ever and current e-cigarette users (AOR: 1.26, 95%CI:1.10,1.44, p <.001; AOR: 1.12, 95%CI:1.02,1.22, p <.02), but not number of e-cigarette devices tried. Impaired self-control was not associated with any outcomes. CONCLUSION: Youth with higher behavioral impulsivity may be more at risk for using more e-cigarette flavors and using e-cigarettes more frequently. Regulations aimed at reducing flavor availability among youth and interventions targeting impulsive behavior may be important for this population.

Does it come from tobacco? Young adults' interpretations of the term "tobacco-free nicotine" in a cross-sectional national survey sample.

BACKGROUND: "Tobacco-free" nicotine (TFN) e-cigarettes and nicotine pouches containing synthetic nicotine are increasingly available. The term TFN may lead to reduced risk perceptions and increased use intentions relative to tobacco-derived nicotine products. Effectively communicating messages about TFN may depend on the public's ability to differentiate TFN from tobacco-derived nicotine. Our goals were to examine knowledge about the source(s) of nicotine in commonly used products and beliefs about what TFN means. METHODS: In 2021 we surveyed 2464 young adults (18-25 years) online. Participants reported whether cigarettes, smokeless tobacco, e-cigarettes, and nicotine pouches contain nicotine that comes from tobacco (always, sometimes, never). Correct responses were "always" for cigarettes/smokeless and "sometimes" for e-cigarettes/pouches. Participants also reported "what [they] think TFN e-cigarettes/vapes contain" (nicotine only; tobacco only; both nicotine and tobacco; neither nicotine nor tobacco). We ran unadjusted and adjusted models examining correct responses for nicotine source and TFN contents by past-month product use status (cigarettes, smokeless, e-cigarettes, pouches). RESULTS: Rates of correctly identifying nicotine source were modest (23.6% pouches-61.9% cigarettes). Except smokeless tobacco, using a given product was associated with identifying its nicotine source correctly in unadjusted models. Participants reported "TFN" means a product contains nicotine only (57.8%), tobacco only (10.8%), both (14.1%), or neither (17.1%). CONCLUSIONS: There is confusion about the source of nicotine in products, and many young adults incorrectly interpreted TFN to mean something other than containing nicotine but no tobacco. Regulatory efforts may be needed to restrict using the term "tobacco-free nicotine" on product labeling and advertising.

Cannabis use among youth who vape nicotine E-cigarettes: A qualitative analysis.

BACKGROUND: Nicotine vaping and cannabis use are common among youth. Among youth who use e-cigarettes, little is known about how and why they use cannabis and patterns of cannabis and nicotine co-use. Given the popularity of both products among youth, the study aim is to utilize qualitative data to better understand cannabis use among youth who use e-cigarettes. METHOD: Six focus groups of high schoolers who reported past-month e-cigarette use (N = 50; 52% male) were conducted to inform e-cigarette cessation programming. We conducted secondary data analysis examining report of cannabis use during focus groups. Transcripts were examined for report of cannabis use, reasons for use, and nicotine and cannabis co-use. RESULTS: In focus groups, cannabis was commonly discussed. Youth reported vaping cannabis, however other forms of cannabis delivery were common (e.g. blunts, joints). Themes related to reasons for simultaneous use of nicotine and cannabis were to experience stronger psychoactive effects than using either product alone and needing to use less nicotine product overall. Reasons for liking cannabis were positive psychoactive effects and stress relief. Reasons for disliking were related to health concerns. Notably, when youth reported disliking cannabis due to health concerns, a common discussion was strategies to acquire and continue cannabis use in ways that they perceived mitigated health concerns. CONCLUSION: Qualitative evidence identified associations between e-cigarette use and cannabis use among youth. Research and interventions targeting youth using e-cigarettes should consider how to address dual use of these products.