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Research paper
Geographic density and proximity of vape shops to colleges in the USA
  1. Hongying Dai1,2,3,
  2. Jianqiang Hao4
  1. 1Health Services & Outcomes Research, Children's Mercy Hospital, Kansas City, Missouri, USA
  2. 2Department of Biomedical & Health Informatics, University of Missouri, Kansas City, Missouri, USA
  3. 3Department of Pediatrics, University of Missouri, Kansas City, Missouri, USA
  4. 4Bellevue University, Omaha, Nebraska, USA
  1. Correspondence to Dr Hongying Dai, Health Services & Outcomes Research, Children's Mercy Hospital, Kansas City, MO 64108, USA; hdai{at}cmh.edu

Abstract

Background Vape shops have been spreading rapidly in the USA since 2008, catering to the fast-growing market for electronic cigarettes. Little is known about the geographic density and proximity of vape shops near colleges.

Methods Names and addresses of vape shops were collected from 3 online directories: Yelp.com, Yellowpages.com and Guidetovaping.com. We identified the prevalence of US-based vape shops and their density and proximity to colleges using a geographic information system. General linear model and negative binomial regression were performed to examine the factors associated with proximity and density of vape shops near colleges.

Results We identified 9945 vape shops in the USA as of December 2015, a nearly threefold increase from 2013. Among the 2755 colleges included in this study, 66.5% had at least 1 vape shop within a 3-mile radius. The median proximity of the nearest vape shop to each college/university was 1.8 miles. Proximity increased by student population, private as compared to public institutions, and location (city vs rural). Within a 1-mile radius, colleges with smoke-free campus policies had a lower density of vape shops (RR=0.6, p=0.002) than those without smoke-free campus policies. Private institutions had a higher density of vape shops (RR=7.8, p<0.0001) than did public institutions. Colleges with campus housing had a lower density of vape shops (RR=0.4, p<0.0001) than those without campus housing, and colleges located in cities had a much higher density of vape shops than those located in rural areas (RR=6.6, p<0.0001). Smoke-free and e-cigarette-free campus policies had significant interactions with college type (private vs public) and campus housing in reducing vape shop density.

Conclusions Vape shops are more likely to be located near private institutions and colleges in cities as opposed to rural areas. Smoke-free and e-cigarette-free campus policies have had significant effects in reducing the density of vape shops but have not reduced the proximity of vape shops to colleges. Regulations on the sale and advertisement of e-cigarettes to youth and young adults are critically needed.

  • Electronic nicotine delivery devices
  • Environment
  • Surveillance and monitoring

http://dx.doi.org/10.1136/tobaccocontrol-2016-052957

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    Introduction

    The use of electronic cigarettes (e-cigarettes) among youth and young adults is becoming more popular in the USA. E-cigarette use among middle and high school students in the USA tripled in 1 year, rising from ≈780 000 in 2013 to 2 450 000 students in 2014.1 A survey of 4444 college students in 20092 shows that 4.9% of college students had used e-cigarettes before, with 1.5% reporting use within the past month. Other surveys conducted in 20133 ,4 show that around 30% of college students reported prior use of e-cigarettes, and 14–15% reported use in the past 30 days. Awareness of e-cigarettes has also grown significantly, from ≈4 in 10 adults in 2010 to 8 in 10 adults in 2013. As a result, e-cigarettes sales in convenience stores, drug stores, grocery stores and mass merchandising stores in the USA more than doubled between 2012 and 2013.5

    The number of vape shops has surged since 2008, catering to the fast-growing e-cigarette market. It is estimated that the number of US vape shops has grown to about 85006 in 2015 from 3500 in 2013.7 Vape shops are retail outlets specialising in the sale and use of Electronic Nicotine Delivery Systems (ENDS). Vape shops allow customers to sample a wide range of ENDS flavours, devices and accessories. Some vape shops look like bars, and some have lounges where customers can drink a beverage as they vape and socialise vaping experience with others.8 Vape shop owners and employees often provide support and advice to promote vape products.9 In many states, vape shops can be easily opened with a business license. The lack of regulations and taxes on the manufacture and sale of e-cigarettes has allowed them to be sold with higher markups than other tobacco products.7 Financial analysts estimate that the vaping industry, which manufactures and sells ENDS, including e-cigarettes, vapours, tanks and other accessories, would generate $3.5 billion revenue in 2015,10 and vape shop sales represent 34% of the total e-vapour market.11

    Studies have shown that retail stores selling tobacco products are disproportionally concentrated in ethnic minority and low-income communities.12–16 Tobacco outlet density is associated with tobacco use, high odds of smoking among adults and smoking frequency.17–19 The proximity to tobacco outlets is associated with reduced likelihood of quitting.20 ,21 However, to the best of our knowledge, no study has investigated the association between vape shop locations and vulnerable populations. Given the surge of e-cigarette use among youth, we hypothesise that vape shops are more likely to locate near young adults and college students. A high vape shop density could increase the propensity of youth to purchase and use e-cigarette products, thus potentially enforcing the acceptability and normalisation of vaping behaviour. Furthermore, youth and young adults are at a high risk of vaping and could potentially use e-cigarettes as a gateway to smoking.22–24 As college students are more likely to use e-cigarettes for enjoyment than for smoking cessation,4 they may be receptive to e-cigarette marketing that promotes product visibility, advertises discounts and encourages social experiments.9 ,25 ,26 Thus, a high density of vape shops around colleges could increase the initiation of vaping among young adults.

    It is important to track vape shops systemically so that we can monitor the growth trend and assess retailers' compliance with youth access laws. However, due to the lack of regulatory policies, including licensing requirements, there is no comprehensive list of ENDS vape shops and very limited administrative records on vape shops.24 Many vape shops do not have tobacco licences, and these businesses are not systematically tracked by state and local agencies for auditing and compliance. Little is known about where vape shops are located and whether they are concentrated in vulnerable communities. Many colleges and universities have implemented smoke-free campus polices, and some colleges have also established e-cigarette-free campus policies.27 However, there is limited literature on how these policies impact vape shop locations. This study is the first of its kind to investigate US-based vape shops using online retailer directories. We further overlaid the geocoded vape shops with colleges/universities, and examined the factors associated with the proximity and density of vape shops near college campuses. The impacts of smoke-free and e-cigarette-free campus policies on vape shop density were also assessed.

    Data and method

    This study consisted of three stages: (1) creating a vape shop database from online sources that have extensive and complimentary listings, (2) linking vape shops to accredited colleges/universities through a geographic information system and (3) analysing the proximity and density of vape shops along with their associations with college characteristics.

    Vape shop data

    A database of vape shops was compiled during December 2015 using three online directories: Yelp.com (with the search term ‘vape shops’), Yellowpages.com (with the search terms ‘vape shops and electronic cigarettes’) and Guidetovaping.com. By trying different search terms and reviewing the relevance of search results, we selected the search terms that were most appropriate for our study. These terms yielded a large number of vape shop listings with high relevance. Additional search terms, such as variants of ‘e-cig’ (ie, ‘e-cigarette’, ‘ecig’, ‘e-cig’) or ‘vape’ (ie, ‘vapor’, ‘vaping’, ‘vape’) had been considered in the search. However, we found these search terms often generated additional listings for retailers that were primarily tobacco outlets. Given our focus to identify vape shop listings, we decided to use a limited number of focused search terms to generate more accurate results.

    A recent study28 validated that Yelp and Yellowpages were the two most accurate online directories in identifying listings of vape stores in Florida. An automated web-scraping software, import.io, was used to search and gather information on vape shops. Yellowpages has over 20 million business listings and 70 million visits each month across its website and mobile apps. The business information is provided by phone companies or the business owner.29 Yelp is designed primarily to publish crowd-sourced consumer reviews about local businesses. It contains information on more than 50 million businesses and has 135 million monthly visitors. The site had 90 million reviews in 2015.30 We included the business name, address, phone number, business description and number of reviews in the data collection from Yelp and Yellowpages. Guidetovaping.com is a commercial website that promotes vaping with coupons, vaping deals and listings of vape shops. Guidevaping.com was included since it is a specific commercial website that includes vape shops not covered by Yellowpages or Yelp (367 of 690 vape shops from Guidevaping.com could not be found in the other 2 sources).

    Given the noise in the online search data, we first geocoded street addresses and removed those that did not match to the geographic information system. Vape shops from Yelp.com had the highest match rate with the geographic information system (99.3%, unmatched=23), followed by Guidevaping.com (98.8%, unmatched=8). Those from Yellowpages.com had the lowest match rate (95.5%, unmatched=387). Unmatched listings often did not have complete address information. For instance, unmatched listings from Yellowpages.com were largely from online stores without specific addresses, such as ‘serve the CA area’ or ‘serve the TX area’ (n=309). Since our focus was to identify vape shop listings, we manually reviewed the business description of listings and removed those for businesses such as art galleries, gas stations, gift shops and clothing stores (n=159) that might sell e-cigarettes but are not actually vape shops. Last, we removed the duplicate listings from among these three online sources (n=1831). Figure 1 summarises the selection criteria and sample sizes for vape shops in this study.

    Figure 1
    Figure 1

    Vape shops in the USA as of December 2015.

    College data

    Data on educational institutions were collected from the National Center for Education Statistics in December 2015.31 The database included the names of 7648 accredited colleges, along with college address, type of college (public vs private, 4 vs 2 years, or <2 years), number of students, school location (city, suburb, town or rural), whether the school has campus housing, and other information. Private for-profit colleges and all institutions with <500 students (n=4893) were excluded from the study, because these colleges are more likely to focus on adult students or online students.

    Data on smoke-free campus status were collected from the Americans for Nonsmokers' Rights Foundation. The data included information on colleges and universities with 100% smoke-free policies, or 100% e-cigarette-free policies campus-wide from three lists: American Indian/Alaska Native colleges with smoke-free policies, US laws requiring smoke-free campuses, and US college and university campuses with smoke-free policies.27

    Vape shop density per 10 000 students was calculated by dividing the number of vape shops within a radius of a college by the college student population.

    Geographic information system

    ArcGIS, V.10.3.1, was used to geocode addresses and overlay vape shops and colleges. The point straight-line distance32 was calculated from each college to the nearest vape shop and multiple-ring buffer zones were created to identify the number of vape shops within a 1-mile and 3-mile radius of each college. A 1-mile radius is a reasonable distance for students to walk and ride a bicycle, while a 3-mile radius is a short driving distance.

    Statistical analysis

    Proximity and vape shop density were calculated for each college. Since the distributions of both variables were right-skewed, they were summarised using median and IQR. Univariate analysis using Kruskal–Wallis H test was performed to compare proximity and density by college characteristics. In the multivariate analysis, college characteristics (student population, smoke-free campus, e-cigarette-free campus, private vs public institution, 4 vs 2 years, campus housing, and locations) were included as explanatory variables. We then treated proximity as a continuous variable and analysed the log (proximity) using the general linear model. Regression coefficients from the general linear model were reported. Negative binomial regression was used to analyse the vape shop density in the 1-mile and 1–3 mile radius of each college. Relative Risk (RR) and 95% CI were reported. Statistical analyses were performed using SAS 9.4 (Cary, North Carolina, USA), and p<0.05 was considered statistically significant.

    Results

    A total of 9945 vape shop addresses were geocoded and analysed in this study. Geographic distributions of vape shops and colleges in this study (n=2755) are presented in figure 2, and circles in figure 2B are proportional to the number of vape shops within a 3-mile radius of each college. Among 2755 colleges included in this study, 30.3% had at least one vape shop within a 1-mile radius, and 66.5% of colleges had at least one vape shop within a 3-mile radius (table 1).

    View this table:
    Table 1

    Number of vape shops within a 1-mile and 3-mile radius of a college*

    Figure 2
    Figure 2

    (A) Geographic distribution of vape shops in the USA, 2015 (n=9945). Each red dot represents a vape shop. (B) Geographic distribution of colleges/universities in this study (n=2755) and the number of vape shops in a 3-mile radius. Each dot represents a college/university. The number of vape shops is shown in the legend.

    The median proximity of the nearest vape shop to each college was 1.8 miles (table 2). Proximity was increased in the following univariate analysis: student population (p<0.0001), private institution as compared with public institution (1.6 miles vs 2.0 miles, p<0.0001), 4 years as compared to 2 years (1.7 miles vs 2.2 miles, p<0.0001), and location (city: 1.1 miles, suburb: 1.9 miles, town: 6.3 miles, rural: 7.9 miles, p<0.0001).

    View this table:
    Table 2

    Density and proximity of vape shops (VS) in relation to colleges and universities, 2015*

    The density of vape shops within a 3-mile radius of each college decreased significantly by smoke-free campus policies (yes: 2.2 vs no: 2.7, p=0.007), e-cigarette-free campus policies (yes: 2.0 vs no: 2.6, p=0.02), public vs private institutions (1.5 vs 7.2, p<0.0001), 2 vs 4 years colleges (1.6 vs 3.4, p<0.0001), and college locations (city: 5.6, suburb: 2.7, town and rural: 0, p<0.0001).

    Multivariate analysis

    Proximity was treated as a continuous variable and analysed by the general linear model (table 3). Colleges with a larger student population enrolment (β=−0.18, p<0.0001), private institutions (vs public, β=−0.25, p<0.0001), and colleges located in a city (vs a rural area, β=−1.84, p<0.0001) were more likely to have a vape shop located near the college. Colleges with campus housing had increased distance from the nearest vape shop (β=0.23, p=0.0002).

    View this table:
    Table 3

    General linear regression: proximity of vape shops to colleges/universities*

    Negative binomial regression was performed to predict the vape shop density within a 1-mile radius or a 1–3 mile radius of a college after controlling the student population as an offset variable (table 4). Colleges with smoke-free campus policies had a lower density of vape shops than colleges without smoke-free campus policies (RR=0.6, p=0.002). Private institutions were more likely to have a higher density of vape shops within a 1-mile radius compared with public institutions (RR=7.8, p<0.0001). Colleges with campus housing had a lower density of vape shops (RR=0.4, p<0.0001) than those without campus housing. Colleges located in cities had a much higher density of vape shops than those located in rural areas (RR=6.6, p<0.0001). We further analysed the density of vape shops within a 1–3 mile radius around a college, and the results were consistent.

    View this table:
    Table 4

    Negative binomial regression*: density of vape shops within <1 mile and 1–3 radius of a college

    Interaction analysis

    Smoke-free and e-cigarette-free campus policies had significant interactions with college type (private vs public) and campus housing (figure 3). Within a 1-mile radius of colleges, private institutions had a higher vape shop density compared to public institutions, but it is promising to see that smoke-free policies (figure 3A) and e-cigarette-free policies (figure 3B) significantly reduced the vape shop density around private institutions. Regardless of campus housing, both smoke-free policies (figure 3C) and e-cigarette-free policies (figure 3D) reduced vape shop densities around colleges, but the policy effect was more evident among colleges with no campus housing. The results of multivariate analysis (table 4) confirmed these significant interactions.

    Figure 3
    Figure 3

    Interaction analysis of vape shop density. (A) Interaction between smoke-free policy and college type; (B) interaction between e-cigarette-free policy and college type; (C) interaction between smoke-free policy and campus housing; (D) interaction between e-cigarette-free policy and campus housing.

    Summary and discussion

    There is a rising trend of vaping among college students. Yet the harmful health risks of vaping, especially over the long term, have not been fully evaluated. E-cigarette use could potentially be a gateway to cigarette smoking for youth and young adults,22–24 as the transition from experimentation to regular smoking and addiction often occurs in young adulthood. Using validated online search methods, we identified nearly 10 000 distinct vape shops in the USA as of December 2015, a 285% increase from 2013.7

    Our study shows that vape shops are prevalent near colleges. A recent study based on interviews with vape shop owners has shown that vape shops use marketing practices resembling current and former tobacco industry strategies, and similarly, attempt to target college students and long-term smokers, thus re-establishing a social norm of smoking.25 Youth and young adults are more likely to visit vape shops and experiment with e-cigarettes for the novelty and flavours instead of for smoking cessation. For example, the latest ‘Monitoring the Future’ survey reported that over half of 12th-grade students who use e-cigarettes said they did so to ‘experiment—to see what it is like’, and 20.5% said they used e-cigarettes because they wanted to ‘have a good time with my friends’.33

    Our study found vape shops had a higher density near colleges in cities as compared to rural areas, and vape shops were also closer in proximity to the colleges in cities. The percentage of colleges with smoke-free or e-cigarette-free campus policies varied moderately across school locations. Among the 2755 colleges included in this study, 26.3%/21.6%/27.9%/29.3% of colleges located in cities/suburbs/towns/rural areas, respectively, had smoke-free campus policies (p=0.02). In addition, 13.9%/10.7%/15.5%/15.5% of colleges located in cities/suburbs/towns/rural areas, respectively, had e-cigarette-free campus policies (p=0.06). We did not find significant interaction between locations and smoke-free or e-cigarette-free policy for vape shop density and proximity of vape shops near colleges.

    Private institutions had a higher density of vape shops within a 1-mile radius compared with public institutions (RR=6.8, p<0.0001), which is consistent with a prior finding regarding waterpipe smoking establishments targeting private institutions.32 Students from private institutions might have higher economic status and higher purchase ability for e-cigarettes compared with students from public institutions, and thus, may be more likely to be targeted by vape shops. In addition, smoke-free or e-cigarette-free policies could also affect the vape shop density around private vs public colleges. We found that public institutions had a higher percentage with smoke-free campus policies (31.3% vs 18.2%, p<0.0001) and e-cigarette-free campus policies (19.6% vs 5.1%, p<0.0001) than did private institutions. We further observed a significant interaction between smoke-free or e-cigarette-free policies and institution type in association with vape shop density, as these policies helped to significantly reduce the vape shop density within a 1-mile radius around private institutions.

    Colleges with campus housing had a lower vape shop density than those without campus housing (RR=0.4, p<0.0001) within a 1-mile radius. The lower density is partly due to the significant interactions between campus housing and smoke-free and e-cigarette-free policies. The policy effects were more evident for colleges without campus housing than those with campus housing, as shown by a steeper reduction in vape shop density within a 1-mile radius (figure 3C,D). One possible explanation could be that colleges with campus housing tend to have more young students, and smoke-free or e-cigarette-free policies are less effective in deterring vape shops.

    Both smoke-free and e-cigarette campus policies were associated with a lower density of vape shops, suggesting that smoke-free and e-cigarette-free campus policies might deter vape shop establishments around colleges. However, neither smoke-free policies nor e-cigarette policies significantly affected the proximity of vape shops to the nearest college. State or local authorities should consider placing limits on vape shops to keep them within a certain distance of colleges and universities.

    Our study is not without limitations. The search terms used in this study were able to identify a large number of vape shop listings with high relevance. However, we might have underestimated the number of vape shop listings given the limited number of search terms and website sources. Although our search methods for vape shops have been adopted and validated in prior studies, we might unintentionally have included vape shops that were not active or did not primarily sell e-cigarette products. Future studies could verify the vape shop listings through crowd-sourcing or field checks, and further develop a systematic tracking system where vape shops can be indexed and searched.

    As this is the first study to identify factors that could potentially affect geographic variations in vape shops, many questions remain open in this field. Other venues, such as convenience stores, drug stores, grocery stores and mass merchandising stores also sell e-cigarette products. The availability of e-cigarettes from these vendors could also influence vape shop density or proximity to colleges but might not have been measured by this study. Future studies could integrate vape shop listings and traditional retailers that sell e-cigarette products to provide a comprehensive landscape of e-cigarette point-of-sale marketing.

    We focused on the proximity and density of vape shops to colleges in this study, but targeting college students might be only a part of the location-based marketing strategy used by vape shops. Future studies should take sociodemographic status into consideration to evaluate whether there exist similar or different social disparities of e-cigarette marketing as traditional tobacco outlets had. We also evaluated the impact of smoke-free and e-cigarette-free campus policies on vape shop density, but vape shop density could also be affected by state-level tobacco or e-cigarette control regulations. Future studies could examine the associations between e-cigarette sales and tobacco and e-cigarette control policies. In light of the rising trend of vaping among youth, the proximity of vape shops to middle schools and high schools also needs investigation.

    Vape shops choose locations as a part of their marketing strategy to expand sales and increase profit by targeting vulnerable populations. Our study provides evidence supporting the need for federal and state-level regulations of vape shops, and for implementation of youth access laws. Vape shops not only sell e-cigarettes but also provide a more casual and welcoming environment compared to traditional tobacco retail outlets. Along with traditional marketing, vape shops often encourage their employees to share their personal experience using vaping products.9 ,25 ,26 We add to the existing literature by examining vape shop density and proximity along with their associations with college/university characteristics. An understanding of the landscape of vape shops, as well as their density and proximity to nearby colleges, could inform policymakers, school administrators and health practitioners to formulate vape-free policies and conduct educational campaigns to prevent youth and young adults from vaping.

    What this paper adds

    • This is the first study to evaluate the association between vape shop locations and a particular vulnerable population: college students and young adults.

    • We estimated the prevalence of vape shops in the USA, with a total of 9945 vape shops as of December 2015. The density and proximity of vape shops to colleges and universities indicate that vape shops are disproportionately located near colleges.

    • This evidence should inform initiatives to limit the marketing of vape shops to youth and young adults.

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    Footnotes

    • Contributors HD conceptualised the study for the article, while JH acquired the data and HD performed the analyses. All authors contributed to writing the manuscript. The authors thank the Medical Writing Center at Children's Mercy Hospital for editing this manuscript.

    • Competing interests None declared.

    • Provenance and peer review Not commissioned; externally peer reviewed.

    • Data sharing statement Data are publically available.