Terms tobacco users employ to describe e-cigarette aerosol

Abstract

Background.

The scientific term for the substance people inhale and exhale from a vaping device is “aerosol,” but whether the public uses this term is unclear. To inform tobacco control communication efforts, we sought to understand what tobacco users call e-cigarette aerosols.

Methods.

Participants were a national convenience sample of 1,628 US adults who used e-cigarettes, cigarettes, or both (dual users). In an online survey, conducted in spring 2021, participants described what “people inhale and exhale when they vape,” using an open-ended and then a closed-ended response scale. Participants then evaluated warning statements, randomly assigned to contain the term aerosol or vapor (e.g., “E-cigarette aerosol/vapor contains nicotine, which can lead to seizures”).

Results.

In open-ended responses, tobacco users most commonly provided the terms vapor (31%) and smoke (23%), but rarely aerosol (<1%). In closed-ended responses, the most commonly endorsed terms were again vapor (57%) and smoke (22%), but again infrequently aerosol (2%). In closed-ended responses, use of the term vapor was more common than other terms among people who were older; white; gay, lesbian, or bisexual; college-educated; or vape users only (all p<.05). In the experiment, warnings using the terms aerosol and vapor were equally effective (all p>.05).

Conclusions.

The public rarely uses the term aerosol to describe e-cigarette output, potentially complicating educational efforts that use the term. Future studies should explore public knowledge and understanding of the terms aerosol and the more popular “vapor” to better inform vaping risk communication.

INTRODUCTION

Millions of Americans are currently vaping, with an estimated 2.1 million youth in 2021¹ and 5.7 million adults in 2019.² Experts generally agree that vaping is a safer alternative for adults unwilling or unable to quit conventional cigarettes, but the net effect of vaping’s benefits and harms across the population remains an ongoing debate in the public health community^3–6 that will take years to resolve as research continues to evolve.⁷

Electronic cigarettes (e-cigarettes) include a battery to heat e-liquid typically containing nicotine, flavoring, and a humectant, to generate a fine aerosol inhaled into the lungs.^{5 8 9} E-cigarette aerosol is made up of tiny particles and generally contains fewer toxic chemicals than the deadly mix of 7,000 chemicals in smoke from regular cigarettes.⁸ However, the emitted aerosol is not a “harmless water vapor”. E-cigarette aerosol can contain harmful and potentially harmful constituents including heavy metals,¹⁰ carcinogenic volatile organic compounds,¹¹ lipid-like compounds,¹² or ultrafine particles¹³ that can be inhaled deeply into the lungs and may pose health consequences over time.^{14 15} Manufacturers do not typically disclose information about chemical ingredients and additives in e-cigarette liquids or their aeresol.^{5 14 16}

The word “vape” as a verb was declared by Oxford English Dictionary¹⁷ as its word of year in 2014, filling a gap emerged in the lexicon, as a term was needed to define e-cigarettes use, and distinguish it from smoking. However, it is unclear what terms communication efforts should use when referring to substance people inhale and exhale from a vaping device. Emerging qualitative evidence shows that the term “vapor” is generally well-known among e-cigarette users who are more likely to use it rather than “smoke”.¹⁸ A recent internet-based search query data using Google Trends revealed that the public appeared to prefer using terms related to “vaping” over “e-cigarette”.¹⁹ These studies paved the way to understand the terminology and language that the public uses to describe vaping-related terms. The scientific community^{5 8 9 14 20 21} primarily uses the term “aerosol” to convey the substance generated by vapes, or use this term to characterize exposure to secondhand material (aerosol) emitted from vapes.^{5 22} However, it is unclear whether the public uses the term aerosol. To inform tobacco control communication efforts and national surveys, we sought to understand the terminology US adult tobacco users employ to describe the aerosol inhaled from e-cigarette devices.

METHODS

Participants

We recruited a convenience sample of 1,628 US adults (≥18 years) who were ever or current e-cigarette users, current cigarette smokers, or dual users through the Qualtrics Online Panel platform. This online panel recruits participants from targeted email lists, social media platforms and other websites, and conducts verification checks on all panel participants.²³

Procedures

In March 2021, participants provided informed consent and completed the survey online. The survey first assessed terms that participants used to describe e-cigarette aerosol with an open-ended item followed by a closed-end item. Survey software then randomly assigned them (between-subjects) to read one of six statements about e-cigarette use: “E-cigarette [aerosol/vapor] contains nicotine, which can lead to seizures”, “E-cigarette [aerosol/vapor] contains harmful chemicals”, or “E-cigarette [aerosol/vapor] contains dangerous metals”). The study team developed the messages based on e-cigarette hazards with substantial or conclusive evidence of harm according to the 2018 report of the National Academies of Sciences, Engineering, and Medicine.³ Participants then rated the statement they read (measures described below). Upon completion of the survey, participants received incentives in a reward type (i.e., cash or reward points) and amount set by the survey company. The Institutional Review Board of the University of North Carolina approved the study procedures.

Measures

Tobacco use.

The survey assessed ever use of vape only, current use of vape only (defined as ever vaped and now vaping some days or everyday),^{2 24} current use of cigarettes only (defined as smoked at least 100 cigarettes and now smoking some days or everyday),² current dual use (vaped and smoked concurrently),^{2 24} and other tobacco products use (past 30-day use of traditional cigars, cigarillos, filtered cigars or little cigars, hookah, pipe filled with tobacco, or smokeless tobacco). ²⁴ Survey questions included images of the assessed tobacco products. The survey assessed whether participants believed that vaping was less, equally, or more harmful than smoking combustible tobacco cigarettes.²⁵

Terms used to describe aerosol.

Participants first answered the open-ended question, “People using cigarettes inhale and exhale smoke. What do people inhale and exhale when they vape?” Two authors (MEK and CAW) independently coded open-ended responses, and the third author (NTB) adjudicated any disagreements (see Appendix Table 1 for coding definitions).

Next, participants completed a closed-ended question, “When people vape, they inhale and exhale _______.” They could choose one of nine response options: Aerosol, Vapor, Smoke, Cloud, Plume, Mist, Steam, Something else, and Not sure (i.e., single response). Finally, participants responded to the same question but could choose any of the response options (i.e., multiple response). For these closed-ended items, survey software randomized order of all but the last two response options. Each randomization was independent of the previous one.

Warning statement experiment.

For the experiment, participants rated the perceived message effectiveness (PME) of a warning statement. We selected PME as the outcome for the experiment because it is sensitive to small differences between messages and is predictive of long-term behavior change^26–29. The PME item read, ‘How much does this message discourage you from wanting to vape?’.²⁹ The five-point response scale ranged from Not at all (coded as 1) to A great deal (5). This single-item PME measure performs similarly to a three-item scale.^{28 29}

Demographic characteristics were age, gender (male or female), sexual orientation (straight or lesbian, gay, or bisexual [LGB]), transgender, Hispanic ethnicity, race (White, Black, or other races), education, and annual household income.

Statistical analyses

To characterize use of the terms overall, we calculated the frequency of use for open-ended, single closed-ended, and multiple closed-ended items. To examine correlates of the use of the term vapor, we conducted multivariable logistic regressions to estimate adjusted odds ratios (aORs) and corresponding 95% confidence intervals (95% CIs). The predictors were demographic characteristics and tobacco use. The outcome was use of the term vapor (coded as 1) vs. other terms (coded as 0) in closed-ended single-response item. The adjusted model controlled for tobacco use status and all demographic characteristics.

To examine the association of the use of terms with accuracy of harm perception, we conducted multivariable logistic regressions. In these models, the outcome was comparative harm perception (vaping is equally or more harmful than cigarettes or not sure (coded as 1) vs vaping is less harmful (coded as 0).³⁰ The predictors were the closed-ended single responses, controlling for demographic characteristics and tobacco use.

Finally, to understand the impact of experimentally assigning participants to messages using the term vapor or aerosol, we compared PME using independent samples t-tests, one for each statement and overall (for the average rating of the three warning statements). Analyses used SAS/STATv14.2 and SPSS v.26, with a statistical significance threshold set at α=0.05.

RESULTS

Fifty-five percent of participants were ages 18-44, 56% female, and 3% transgender. Most were White (85%), 31% had a high school degree or less, and 30% had an annual household income of less than $25,000 (Table 1). Four percent of participants reported ever use of vapes only, 11% current use of vape only, 44% current use of cigarettes only, and 41% were current dual users.

Table 1.

Demographic and tobacco use characteristics (n=1,628)

Demographic characteristic	n	%
Age, years
18-24	123	8
25-44	767	47
45-64	479	29
65+	259	16
Gender
Female	903	55
Male	715	44
Non-binary or something else	10	1
Transgender
No	1586	97
Yes	42	3
Sexual orientation
Straight	1415	57
Gay, lesbian, or bisexual	214	13
Hispanic
No	1508	93
Yes	118	7
Race
Black or African American	116	7
White	1376	85
Other races	136	8
Education
High school or less	509	31
Some college	416	26
Undergraduate or Associate’s degree	461	28
Graduate degree	242	15
Household income, annual
$0-24,999	481	30
$25,000-49,999	411	25
$50,000-74,999	228	14
$75,000 or more	508	31
Tobacco use
Ever use of vape only	65	4
Current use of vape only	182	11
Current use of cigarettes only	721	44
Dual use	660	41
Other tobacco product use¥	676	42
Harm perception of vaping compared to cigarettes
Less harmful	501	31
Equally harmful	693	42
More harmful	327	20
Not sure	108	7

^¥Note. Other tobacco products include traditional cigars, cigarillos, filtered cigars or little cigars, hookah, pipe filled with tobacco, and smokeless tobacco (such as snus, moist snuff, dip, spit and chew). Missing values were <1%.

Terms used to describe e-cigarette aerosol

In open-ended responses, 1,441 (89%) of study participants provided codable answers. The most common terms generated in open-ended responses were vapor and smoke (mentioned by 31% and 23% of respondents), followed by chemicals (12%), nicotine (9%), water (5%), metal (5), toxic (3%), liquid (or e-liquid) (3%), or carbon monoxide or other gases (3%) (Table 2). In closed-ended responses (pick only one), the most common terms were again vapor (57%) and smoke (22%), followed by steam (5%), mist (4%), and cloud (2%), but again infrequently aerosol (2%) (Table 2). The pattern stayed the same when participants had a chance to select multiple of the response options; vapor (64%) and smoke (33%) were the most common terms, and aerosol (9%) remained among the least frequent (Table 2). For participants who used the same term in both open- and closed-ended responses, the most common term was vapor (27% of participants), followed by smoke (11%) (Appendix Table 2). The pattern was similar for closed-ended only responses (vapor 31%, smoke 12%), but reversed for open-ended only responses (smoke 10%, vapor 3%).

Table 2.

Terms used to describe e-cigarette output (n=1,628)

	Open-ended response (%)a	Closed-ended responses (%)
		Single response	Multiple responses b
Vapor	31	57	64
Smoke	23	22	33
Steam	3	5	18
Mist	1	4	21
Aerosol	0.2	2	9
Cloud	0	2	10
Plume	0	1	4
Not sure	8	5	5
Something else	-	2	4
Chemicals	12	-	-
Nicotine	9	-	-
Water	5	-	-
Metals	5	-	-
Toxic	4	-	-
C.O. or other gases	3	-	-
Liquid	3	-	-

^aOpen-ended responses came from n=1,441 participants who mentioned codable terms. In open-ended responses, ≤1% of respondents used terms that we coded into these categories: Air, Oils, Flavor, Combustible tobacco, Fumes, Moisture, or Diseases.

^bSum of the percentages may surpass 100 because participants were allowed to opt more than one term.

In terms of correlates of selecting vapor in the closed-ended single responses (Table 3), use of the term vapor was more common among people who were older, LGB, White, college-educated, or current users of vape only (all p<.05). Past 30-day users of other tobacco products were less likely to use the term vapor (p<.05).

Table 3.

Correlates of using the term vapor in closed-ended single responses (n=1,628)

Characteristics	No. who used the term vapor/No. in category	Univariate analysis	Multivariable analysis
	n (%)	OR (95% CI)	OR (95% CI)
Age, years
18-24	58 (47)	Ref	Ref
25-44	389 (51)	1.15 (0.78-1.68)	1.80 (1.15-2.81)
45-64	311 (65)	2.08 (1.39-3.10)	2.44 (1.52-3.93)
65+	177 (68)	2.42 (1.55-3.75)	2.65 (1.55-4.52)
Gender
Male	374 (52)	Ref	Ref
Female	555 (62)	1.45 (1.19-1.77)	1.04 (0.83-1.32)
Non-binary or something else	6 (60)	1.36 (0.38-4.88)	1.14 (0.29-4.54)
Transgender
No	914 (58)	Ref	Ref
Yes	18 (43)	0.54 (0.29-1.01)	0.55 (0.28-1.09)
Sexual orientation
Straight	797 (56)	Ref	Ref
Lesbian, gay, or bisexual	138 (65)	1.42 (1.06-1.92)	1.81 (1.29-2.53)
Hispanic
No	880 (58)	Ref	Ref
Yes	55 (47)	0.62 (0.43-0.90)	0.75 (0.49-1.13)
Race
Black or African American	48 (41)	Ref	Ref
White	811 (59)	2.03 (1.38-2.98)	1.80 (1.19-2.72)
Other races	76 (56)	1.79 (1.08-2.96)	1.66 (0.97–2.83)
Education
High school or less	291 (57)	Ref	Ref
Some college	284 (68)	1.61 (1.22-2.11)	1.58 (1.19-2.10)
Undergraduate or Associate’s degree	251 (54)	0.89 (0.69-1.15)	1.09 (0.81-1.47)
Graduate degree	109 (45)	0.61 (0.45-0.83)	0.94 (0.63-1.40)
Household income, annual
$0-24,999	285 (59)	Ref	Ref
$25,000-49,999	272 (66)	1.34 (1.02-1.76)	1.23 (0.92-1.64)
$50,000-74,999	139 (61)	1.07 (0.77-1.48)	1.04 (0.73-1.47)
$75,000 or more	239 (47)	0.61 0.47-0.78)	0.77 (0.55-1.07)
Tobacco use
Dual user	341 (52)	Ref	Ref
Ever use of vape only	40 (62)	1.49 (0.88-2.52)	1.38 (0.79-2.40)
Current use of vape only	117 (64)	1.68 (1.19-2.36)	1.60 (1.09-2.36)
Current use of cigarettes only	437 (61)	1.43 (1.16-1.78)	0.89 (0.69-1.16)
Other tobacco product use
No	627 (66)	Ref	Ref
Yes	308 (46)	0.43 (0.35-0.53)	0.60 (0.47-0.77)

None of the terms selected in closed-ended responses predicted relative harm perception (all p>.05), in multivariable models controlling for demographic characteristics and tobacco use (Appendix Table 3).

Experiment

Warning statements with the term aerosol or vapor did not elicit different levels of PME overall (p>.05) (Appendix Table 4). The mean (SD) PME for the warning statements with term vapor was 3.43 (1.29) and for aerosol was 3.41 (1.36). Additional analyses for each of the three warning statements alone (and by the terms that respondents used) also found null results.

DISCUSSION

In a large US study, adult tobacco users described substance emitted from vaping devices differently than the scientific community.^{5 8 9 14} Participants most often reported using the terms vapor and smoke in both closed and open-ended responses, but rarely aerosol. In open-ended responses, few participants mentioned using the terms chemicals, nicotine, water, metals, toxic, or liquid to describe the substance of what people inhale and exhale when vaping. We also observed differences in using these terms across demographic groups, with vapor being more common among older individuals, LGB, White, college-educated, or current users of vape only. Additionally, our null findings for relative harm perception showed that use of the terms vapor and aerosol did not appear to be associated with a variable that might motivate or hinder e-cigarette use.

Vapor and smoke (but not aerosol) were the most common terms used by tobacco users to call substances they inhaled from vaping devices. This was in line with a previous qualitative study¹⁸ showing that people often use both smoke and vapor interchangeably to describe e-cigarette emissions. Although we did not measure the participants’ knowledge and understanding of vaping-related terminology, these findings signal that public may not differentiate (and understand) what is in vapor (or aerosol) and how it differs from smoke. Fifty years after the first Surgeon General report³¹ on the health consequences of cigarettes, the public knows little about what is in smoke, with most people only being able to reliably identify carbon monoxide, nicotine, and tar³². It is unclear how these misused terms such as smoke—along with rapid evolution in e-cigarette marketing and authorizing commercial e-cigarettes by FDA—will shape the evolving product terminology. Additionally, it is poorly understood whether using the scientific term aerosol in public-facing materials, national surveys, policy, and risk communications will keep pace with the changing product landscape.

To describe e-cigarette output, smoke is an incorrect term due to the noncombustible characteristic of vaping. Although e-cigarette users may use the term smoke to describe e-cigarette’s emissions,¹⁸ they tend to prefer not to be called smokers, partially due to the associated stigma.³³ Our findings showed smoke as the second most common term to describe e-cigarette emissions, after vapor. It is unclear how these population patterns of using languages—with rapid pace of e-cigarettes marketing evolution—will shape the growing product nomenclature and whether different segments of the user population will adopt diverse terminology.¹⁸ This may also hinder effective risk communication efforts that use the term aerosol to communicate the potential risks of e-cigarette outputs or apply it to an aerosol-free environment.

Our findings revealed heterogeneity among people who uses the term vapor compared to other terms. For example, LGB adults who vape nearly twice that of heterosexual adults³⁴ were more likely to use term vapor than other terms. While vaping is a popular route of nicotine delivery among young adults (18-24 years)³⁵, using the term vapor is less popular in this age than in older age cohorts. Nevertheless, adults who only vaped were more likely to use the term vapor compared to dual users of vapes and cigarettes. These discrepancies in characteristics of using terms vapor may make it challenging to target specific populations in risk communication and regulatory efforts associated with e-cigarettes use. Given these differences, to ensure the success in tobacco prevention and cessation programs, it will be important to understand the public’s knowledge about terms (e.g., vapor vs aerosol), raise awareness about scientific terms (e.g., aerosol)-especially in vulnerable populations- and monitor the languages used by the public along with the rapid evolution in tobacco products marketing and update strategies accordingly.

Use of the most common terms, including vapor, smoke, and steam, was not associated with perceived risk of harm of vaping relative to smoking cigarettes. Warnings statements with the terms aerosol and vapor yielded equivalent PME in our experiment. Tobacco users may not fully appreciate the differences between the term vapor and scientific term aerosol when it comes to communicating vaping risks through warning messages. Given that our warning experiment yielded null results, it is unclear if public-facing materials (e.g., vapor-free laws), warnings messages, or anti-vaping campaigns³⁶ that use the term vapor in lieu of aerosol will lead to effective risk communication results. With rapidly diversifying vaping products category, the heterogeneity in language used by the research community,^{5 37–40} tobacco users^{18 41} or manufacturers^{42 43} to describe vaping terminology (e.g., aerosol, vapor) may hinder developing effective risk communication.

No participants in our study mentioned the term cloud in open-ended responses, with only 2% mentioning it in a closed-ended single response question. However, studies have found the term cloud is a well-known term among vape users.^44–46 “Cloud-chasing” was a popular activity, particularly among young people, of blowing a large or dense cloud of aerosol using older generations of vapes.^44–47 Although vape users are familiar with the term “cloud” or “plume,” they do not call it a substance they inhale into their lungs and exhale as a cloud with potential risks to bystanders.⁴⁸ Future studies are warranted to explore whether youth refer to the cloud as a substance they inhale or exhale from their vapes and understand this term. In the meantime, anti-vaping educational campaigns need to raise awareness about the vaping terminology (e.g., cloud) and potential risks of cloud-chasing—which is largely used as marketing tactics to attract nicotine-naïve customers.⁴⁷

Study limitations include the use of a convenience sample of adults, potentially limiting the generalizability of study findings to other populations or samples. However, convenience samples may yield similar rank orderings of ratings and often yield similar experimental findings compared to probability-based samples.^{49 50} Second, the results may differ in adolescent tobacco users. Given concerns about vaping as a gateway for combustible tobacco products among nicotine-naïve young people,⁵¹ future studies should examine the terms adolescents and young adults who have neither smoked nor vaped employ to describe aerosol. Future studies should also explore public knowledge and understanding of the terms aerosol and vapor to better inform vaping risk communication, a topic our research did not directly address. Third, the initial open-ended question included the term “smoke”, which may have affected later responses. Indeed, the prevalence of use of the term vapor increased substantially in the closed-ended responses, whereas the use of smoke remained largely unchanged. For this reason, our survey may have overestimated use of the term smoke for vape emissions. Finally, aerosol as a term has been heavily covered in the media because of the COVID-19 pandemic by emphasizing how coronavirus spreads in the air. The unpopularity of the term aerosol suggests that public health prevention or communication efforts to promote using the term aerosol for vaping may not be especially successful among the public without substantial additional educational efforts around the term.

What is already known on this topic.

• The scientific community primarily uses the term “aerosol” to convey the substance generated by vapes, or use this term to characterize exposure to secondhand material (aerosol) emitted from vapes.

• it is unclear whether the public uses the term “aerosol”.

What this study adds

• Among a large sample of US adult tobacco users, the most common terms to describe the substance inhaled and exhaled from a vaping device were vapor and smoke, but seldom aerosol.

How this study might affect research, practice or policy

• Anti-vaping campaigns using the term aerosol may not resonate with the public who rarely use the term.

• Future studies should explore public knowledge and understanding of the terms aerosol and vapor to better inform vaping risk communication and regulatory policy.