Communicative Processes Underlying DIY eJuice Mixing Among Young Adult International ENDS Users.

The use of electronic nicotine delivery systems (ENDS) is increasing around the world, with contemporary trends outpacing scientific understanding of the health implications. Such trends include do-it-yourself eJuice mixing (DIY eJuice), which involves the unregulated homemade mixing of fogging agents, nicotine salts, and flavorants to create personalized liquid for ENDS products. The purpose of this study was to employ a grounded theory approach to gather formative data on the communicative processes surrounding the behavior of DIY eJuice mixing among international, young adult ENDS users. Participants were recruited locally for mini focus group discussions via SONA (n = 4) and internationally for an open-ended survey via Prolific (n = 138). Questions explored experiences with the online DIY eJuice community, motivations for mixing, information seeking strategies, flavor preferences, and perceived benefits of mixing. Thematic analysis and flow sketching revealed the underlying processes of social cognitive theory to explain the communicative processes of DIY eJuice mixing behaviors. Specifically, environmental determinants emerged in the form of online and social influences; personal determinants in the form of curiosity and control; and behavioral determinants following a benefits/barriers analysis, particularly regarding cost. These findings provide theoretical implications for the role of health communication constructs in understanding contemporary trends in ENDS use and practical implications for tobacco prevention messaging and tobacco control regulations.

Using the Theory of Planned Behavior to Anticipate DIY E-juice Mixing among Young Adult International E-cigarette Users.

Background: Trends in young adult use of electronic nicotine delivery systems (ENDS) and experimentation with do-it-yourself (DIY) e-juice mixing are growing around the world. Theoretical frameworks for examining secondary behaviors (i.e., mixing) embedded within a primary behavior (i.e., vaping) are limited, leading to challenges in scholarly understanding of behavioral performance. This study explored the theoretically driven factors surrounding ENDS users' decision to mix DIY e-juice through a multiple behavior test of the theory of planned behavior (TPB). Methods: An international sample of young adult participants aged 18-19 (n=203) was recruited from Prolific for an online crosssectional survey. Path modeling tested four theoretically driven models to explore behavioral performance of mixing. Findings: The data supported TPB expectations and revealed new paths for secondary behavior. Primary perceptions of attitudes, norms, and intention were predictive of the same secondary perceptions. In addition, for both primary and secondary behaviors, perceived norms were a function of perceived attitudes. For the secondary behavior, normative influence was experienced indirectly through perceived attitudes. Conclusion: DIY e-juice mixing is a product of perceived attitudes and behavioral control surrounding mixing as well as perceived attitudes, norms, and intention surrounding general ENDS use. While unregulated DIY experimentation increases among youth, these findings provide a lens for public health efforts seeking to reach and reduce use. Understanding DIY e-juice behaviors is essential to anticipate stockpiling behaviors and negative outcomes from amateur experimentation.