The global toxic, nonbiodegradable environmental waste from tobacco, e-cigarette, and cannabis waste (TECW) products is a pressing public health issue [1-4]. Upstream policy approaches [5] to address this increasingly recognized waste problem [6-11], such as banning sales of filtered cigarettes [12] and naming them as single-use plastics that may be addressed in a proposed international plastic treaty [13], are important for both environmental and human health reasons [14]. Awareness of the environmental impacts of e-cigarette [1,2,15-19] and cannabis vape products is also growing [2,19-22]. According to the Environmental Protection Agency (EPA), vape products cannot be safely discarded in household trash or recycled; they meet the definition of “hazardous waste.” Many consumers are unaware of this designation, but the EPA has provided guidance to separate batteries from other vape product components that are to be disposed of as municipal hazardous waste [23]. Furthermore, single-use or “disposable” vape products are not designed to be safely disassembled [24].

Disposable nicotine vape products are the most commonly sold [25] and used products in the United States [26], creating a growing environmental challenge [24]. In addition to fires caused by improper disposal of the lithium-ion batteries in vape products, the high-carbon impacts of vape product manufacturing are of concern [27]. The majority of young adults who use disposable nicotine vape products report throwing them in the trash when empty [24]. This provides an estimated 150 million disposable vapes (with potentially recoverable lithium) deposited annually in US landfills [27]. Nearly a quarter of young adults who use vape products report saving the empty products, which also presents a safety issue [24]. There have been no studies to our knowledge on disposal methods for cannabis vape products.

Cultivating public and political support for legislative and regulatory interventions for TECW requires increasing knowledge and modifying perceptions of TECW, and increasing public engagement with policies that can reduce use of tobacco and cannabis products [28]. Research is required on how to influence behaviors that support TECW regulatory policies. To date, there have been 2 observational studies on cigarette butt waste, which both showed that education promotes positive attitudes and behaviors regarding TECW regulations [28,29]. There has not yet been specific research conducted on interventions to increase knowledge, perceptions, and policy engagement on e-cigarette or cannabis product waste. A randomized controlled trial will provide important evidence on the efficacy of such interventions to address TECW, especially among young persons who generally are more engaged on environmental issues.

This study tests the administration of tobacco, e-cigarette, and cannabis waste education plus motivational and behavioral support (TECW Ed+) versus tobacco, e-cigarette, and cannabis waste education (TECW Ed) only on TECW among college-attending young adults (aged 18-25 years) to increase their engagement on TECW policy implementation. Brief education is standard of care in university settings, and given our finding that awareness of a technological resource is not sufficient for many people to use it [30], we sought to determine whether the addition of motivational enhancement and behavioral support to education would elicit action.

Outcomes include change in TECW knowledge, harm perceptions, attitudes toward regulation, and smoke- and vape-free regulatory policy engagement. Our overall goal is to identify an evidence-based educational intervention to address TECW, based on environmental concerns [31].

Such interventions are particularly relevant among young people, who are the critical stakeholders in planetary stewardship [32]. Students in California public universities are an important constituency for tobacco-related research given that the 23-institution California State University system and the 10-institution University of California system have 100% smoke- and vape-free campus policies, albeit with persistent policy violations [33]. Compliance issues at California public universities and colleges are emblematic of a broader smoke- and vape-free policy compliance problem at universities [34-36].

The specific study aims are to: first, assess knowledge and perceptions about TECW among participants randomized to the TECW Ed+ group compared to those randomized to the education-only control group (TECW Ed). It is hypothesized that at week 6, the TECW Ed+ group will demonstrate a significant increase in knowledge about TECW, perceived harmfulness of TECW, and the attitude that TEC manufacturers should be accountable for waste mitigation, and that the TECW Ed group will be noninferior to the TECW Ed+ group in these outcomes. Second, assess TECW-related behaviors among college students randomized to the TECW Ed+ group compared to those in the comparison group. It is hypothesized that at week 6, the TECW Ed+ group compared to the TECW Ed group will display greater usage of a campus-based TECW Tracker to report TECW on campus and stronger engagement in supporting smoke- and vape-free regulatory efforts. Third, document changes in campus TECW to understand the environmental impact of a TECW intervention. TECW on campus will be measured each week using 3 sources: Tracker-based participant reports, Tracker-based nonparticipant reports (eg, other members of the campus community), and repetitive objective environmental scans by the site team.

This is a parallel randomized controlled trial at 2 California universities (1 University of California and 1 California State University) in which a digital TECW Tracker was previously deployed for reporting locations of smoking, vaping, and related waste on campus [30,37]. We enrolled 406 young adult students in a 6-week trial and randomly assigned them 1:1, stratified by site and tobacco or cannabis use status, to usual education only about TECW (TECW Ed) or to receiving the same education about TECW plus motivational enhancement and behavioral support for reporting TECW (TECW Ed+). Changes in individual-level and environmental outcomes are evaluated through repeated assessments at baseline, week 2, week 6, and week 26. Check-in text messages only are provided at weeks 1 and 4.

The guiding framework for this study is social cognitive theory [38,39]. in which behavior is conceptualized as the product of individual-level attitudes and perceptions and social structures that facilitate behavior change. In this study, we use motivational enhancement [40-47], goal setting [48-54], and problem-solving applications [55-60] as developed in our previous trial [61]. Our intervention was designed to address both individual-level attitudes and perceptions and social-level factors through the application of motivational enhancement, which is built around 4 main processes, carried out in a spirit of collaboration, respect, and support for the participant’s autonomy [54]. The first process, engaging, reflects fundamental communication principles and highlights the importance of empathy in establishing trust and rapport. The second process, focusing, involves working with participants to identify and agree on a topic for exploration. The third process, evoking motivation, is directed at drawing out and reinforcing participants’ own internal motivations for change. The fourth process, planning, guides participants in developing and implementing concrete steps toward their goals. The intervention protocol, in which motivational enhancement, goal setting, and problem solving were used to evoke changes in individual- and social-level factors per social cognitive theory, was adapted from one target behavior [61] to another (using TECW Tracker).

The study was reviewed and approved by the Institutional Review Board at Site 1 (#1896205-1) on April 12, 2022. The study was reviewed and approved as exempt by the Institutional Review Board at Site 2 (#1952501-1) on September 2, 2022. Enrollment began on March 1, 2023, and concluded on October 15, 2024.

The informed consent form is delivered to participants by an emailed link in Research Electronic Data Capture (REDCap; Vanderbilt University), along with a link to schedule their baseline visit. The consent form asked, “Would you like to proceed with this study?” using a forced-choice question with two options: I do not wish to proceed with this study or I wish to proceed with this study. Written consent is provided through a typed name with acknowledgment of being aged 18 years or older, of having read and understood the study description, and that they may withdraw at any time. REDCap records the date of consent form completion.

At the beginning of the baseline visit, a description of the study, requirements, and compensation is reviewed; there is an opportunity to ask questions, and participants are asked whether they wish to proceed with the study. Any participants who have not completed the consent form prior to the visit are provided as much time as they need to read the form in a breakout room at the beginning of the visit.

Participants receive up to US $110 for participating in the study: US $25 for attending the baseline, week 2, and week 6 visits, and US $35 for the month 6 visit (Figure 1).

The study is conducted in San Diego, California, United States (Site 1), and Davis, California, United States (Site 2). A project coordinator at Site 1 is responsible for participant recruitment and enrollment at both campuses and supervises Site 1–based research assistants. The intervention and assessments are delivered remotely by research assistants at Site 1 to participants at both sites. Participant education and TECW Ed+ group interaction occur over Zoom (Zoom Video Communications, Inc) as a one-to-one session with a research assistant. This method aligns with new norms for synchronous remote participation in university settings. Participants are provided links to surveys and forms in the Zoom chat and are placed in a breakout room to complete them. They are instructed to use the “ask for help” function or rejoin the main Zoom room with questions about the survey. The project coordinator reviews Tracker data and supervises staff at each site who conduct environmental scans and document TECW identified through the Tracker at both campuses.

Knowledge, perceptions, and regulatory attitudes for vape-related waste are tested before and after receiving education at the baseline visit. Knowledge, perceptions, and regulatory attitudes for cigarette waste are tested before and after receiving education at the week 2 visit. Knowledge, perceptions, and regulatory attitudes for vape-related waste and cigarette waste are retested at the week 6 and week 26 visits (Figure 2).

Enrollment is conducted from the second week of each semester or quarter until 6 weeks before final examinations week. Enrollment begins the second week of the semester to assure that past 7-day questions refer to a time of typical campus activity. When there is a campus break of 2 weekdays or longer, study visits are delayed by a week to adjust the past 7-day question time period for typical campus activity. The stop date each semester or quarter assures that the 6-week intervention is delivered while participants are still attending class on campus at least once per week.

An initial sample size of 400 total (100 per group per campus) will detect a 15-16 percentage point difference in proportions with 80% power at the 0.05 level (2-sided), assuming a sample size of 380 at 6 weeks (95% retention) and 340 at 26 weeks (85% retention). This effect size is expected based on previous research on attitudes and behaviors [67]. This sample size also provides more than 95% power to detect noninferiority within a 0.5 SD margin at the 0.025 level (1-sided) or a difference in means of 0.5 SD at the 0.05 level (2-sided); 0.5 SD is considered a minimally important difference in health-related quality of life outcomes [70] and corresponds to 0.5 point difference on a 5-point scale with an SD of 1 point.

Participants are recruited from each site using campus announcements, flyers, tabling, and word of mouth through campus partners.

After completing the baseline survey, participants at each site are randomized 1:1 to the two groups (TECW Ed or TECW Ed+) in blocks stratified by tobacco or cannabis user status (any use in the past 30 days: yes or no) by the project coordinator using REDCap, based on randomization tables created by the study statistician with computer-generated random numbers.

Research assistants are aware of group assignments and deliver the designated intervention. Participants are not told their group assignment. Research assistants are unaware of study hypotheses and do not see participants’ before and after survey responses. Research assistants are aware of the number of Tracker reports and their nature because providing feedback to the TECW Ed+ group is a component of the intervention.

At the baseline and week 2 visits, a presurvey is administered before education and a postsurvey is administered after education (plus motivational enhancement for the intervention group). Assessment windows are ±3 days for the week 1 check-in, ±1 week for the week 2 visit and week 4 check-in, ±4 weeks for the week 6 visit, and ±6 weeks for the week 26 visit.

The study uses a rigorous design to evaluate an educational intervention that can improve knowledge, attitudes, and behavior regarding tobacco and cannabis product waste. This improved knowledge and belief system is expected to support the implementation of tobacco- and vape-related environmental regulatory policies. Such interventions may increase smoke-free policy adherence and support efforts to enforce smoke- and vape-free campus policies. Educational efforts using an environmental lens, paired with a focus on industry accountability, may also support quitting efforts [77], contributing to long-term efforts to reduce the health and economic burdens of tobacco product use [78].

Universities are critical settings in which to prevent initiation of vaping, as a greater number of college students than noncollege students begin using e-cigarettes in young adulthood [79]. There are an estimated 19.9 million college students in the United States, providing an opportunity for a variety of targeted interventions to address the current epidemic of e-cigarette use. This investigation, involving a clinical trial of an intervention aiming to change what young adult college students know about TECW and how they can support policies to reduce this environmental problem, may stimulate similar research and policy implementation in other campus settings.

There are several limitations to note regarding this trial. First, while the study involved a single site in each public university system in California, these 2 sites are not necessarily representative of all public universities. Furthermore, state universities are not representative of other educational settings such as community colleges, private universities, and trade schools. Second, young college-attending adults aged 18-25 years were the target population for this study, assuming their more active interest in environmental protection [32]. However, the results may not generalize outside this age or educational group. Nevertheless, these young adults are more likely to initiate vaping then noncollege-attending young adults [79] and a need for improved smoke-free campus policy compliance in these settings was identified in previous research [34-36]. Finally, given that this is a very closely controlled trial of an educational intervention, it is uncertain if such an intervention will be effective in a real-time setting. The efficacy of the intervention is established in the controlled research setting, then followed by wider implementation and evaluation in the real world [31].

This study expands on previous studies addressing the harms of cigarette butt waste, to include nicotine- and cannabis-vape–related waste. This study also uses a more rigorous design than previous observational studies [28,29]. The common approach used by the previous observational studies and our randomized trial was education to increase knowledge about the environmental harm of tobacco product waste. We extended this approach by using brief videos to deliver additional messages on not only cigarette butt waste but also including vape products for nicotine and cannabis. This study is novel in testing whether motivational enhancement and behavioral support add value in creating behavior change versus using education only.

A follow up, larger implementation study would be a valuable next step to apply the intervention in various settings and conditions. Additional efficacy studies in different settings (eg, community college) and policy conditions (eg, colleges with designated smoking or vaping areas) would be beneficial. Our behavioral measures, such as Tracker usage and change in TECW disposal methods, will be central in planning future studies.

This trial aims to evaluate educational tools to promote effective smoke- and vape-free campus policies. It investigates whether brief educational videos will increase knowledge of the environmental impact of TECW and change harm perceptions and attitudes toward regulatory policies on cigarettes and vape products. We will also learn whether education alone is sufficient to increase engagement in smoke- and vape-free regulatory policy support, or whether the addition of motivational enhancement and behavioral support is necessary to produce change. This study will be the first randomized controlled trial modifying cigarette waste perceptions and behaviors and is novel in its inclusion of nicotine- and cannabis-vape–related waste educational interventions.