Current research indicates that secondhand marijuana smoke contains many of the same chemicals as secondhand tobacco smoke and some in greater concentrations with recent studies demonstrating that secondhand marijuana smoke has negative cardiovascular effects similar to tobacco smoke.Non-smokers exposed to secondhand marijuana smoke had detectable levels of THC and metabolites, with levels increasing when higher potency marijuana was used.Non-smokers exposed to cannabis smoke for 60 min in an unventilated room had detectable levels of THC in blood following the exposure, increased heart rate, mild to moderate self-reported sedative drug effects and performed worse on a cognitive test.As normalisation of marijuana use continues, it is important to monitor the effects of normalisation on tobacco use, perceptions and smoke-free spaces. Smoke-free policies should cover all products, including combustible marijuana and electronic vaporisers for tobacco and marijuana. Signs and information signalling smoke-free policies should be adapted to clearly include marijuana smoke where applicable. Information about harmful effects of secondhand tobacco smoke was found to be a deterrent to smoking initiation and a motivator for cessation for youth.Studies should explore messaging around the negative effects of secondhand marijuana smoke. As a qualitative study,hydroponic rack system our relatively small sample provides insight into how some young adults in Colorado integrate tobacco, marijuana and vaporiser use.
While these experiences may not be representative, this work begins to shed light on how these products are used and made sense of alongside one another. Further in-depth qualitative work is needed to document the complexities of perceptions of tobacco and marijuana in distinct legal contexts , and examine differences between perceptions of medical and retail marijuana in relationship to tobacco. More work is also needed to understand those who primarily vaporise nicotine, those who vaporise marijuana and those who use both. The SCTC research initiative addresses high-priority gaps in tobacco control research through collaboration between academic researchers and local tobacco control agencies and community organisations. Legalisation of marijuana is one area that is highly salient for many state and community tobacco programmes because of its potential to affect use and perceptions of tobacco. Moreover, tobacco control experts within agencies are frequently tasked with recommending marijuana policies or educating citizens about rules of use and potential health effects. Tobacco, marijuana and vaporisers are most effectively studied together and future research should address perceptions of comparative harm of these products; social, political and health effects of their use; and adequate measurement of use patterns, especially when products are combined. Finally, tobacco programmes and policies should take into account emerging research on the complexities of this triangulum, particularly in the context of marijuana legalisation.Following recreational marijuana legalization and commercialization in the US, marijuana dispensaries have served as a major venue for marijuana retail sales in neighborhoods.
Nonetheless, research on the impacts of marijuana dispensaries on public health remains limited . Availability, accessibility, and point-of-sale marketing of retail outlets have been associated with attitudes, perceptions, and health behaviors in tobacco and alcohol literature . Marijuana dispensaries may impact marijuana-related outcomes in a similar manner. They may increase availability and accessibility of marijuana , promote greater awareness and consumption through marketing activities , increase product appeal such as through increased quality and potency , diversify product variation such as vaping devices and edibles , reduce prices through mass production and introduction of competition , and shape social norms favorable of marijuana use . A major challenge in understanding the availability and retail environments of marijuana dispensaries is identifying a complete and accurate list of marijuana dispensaries in neighborhoods. In a state operating a statewide licensing system, one can obtain the official licensing directories from government databases. Nonetheless, most of these directories are updated infrequently. More importantly, they do not reflect the operation status of dispensaries in reality or capture unlicensed dispensaries that are common in areas with weak law enforcement. Business directories provided by commercial providers are commonly used to identify tobacco, alcohol, and food retail outlets when state licensing directories are unavailable or unsatisfactory . Unfortunately, these commercial databases had not systematically gathered information on marijuana dispensaries by the time of this study. One can also conduct a field census with direct search and observation to enumerate a certain type of business in a geographic area. It is considered to be the best practice in outlet identification and often used to validate the business lists obtained from commercial databases . The limitation of field census is obvious: the required efforts and resources increase exponentially as the geographic area of interest expands.
Due to practical and budget concerns, most tobacco, alcohol, and food outlet studies that adopted this method searched retail outlets in smaller regions such as a county . State-level field censuses, especially in a large state like California, are nearly nonexistent. In light of the challenges of using conventional approaches to identify marijuana dispensaries, existing studies have primarily relied upon a single or a few online crowd sourcing platforms, such as Weedmaps, Leafly, and Yelp, to obtain dispensary information voluntarily submitted by dispensary owners and marijuana users . Because these platforms serve as online communities to promote dispensaries, products, and share experiences, they are perceived to be more up-to-date and comprehensive than official licensing directories. Particularly, these platforms provide data on both licensed and unlicensed dispensaries. Despite the increasingly common use of online crowd sourcing platforms in marijuana research, the validity of this approach has not been comprehensively assessed at statewide level. To date, only two studies have conducted validation in a single county , one before recreational marijuana commercialization and one after the commercialization in California. In this study, we examined the validity of using secondary data sources, including the state licensing directory and commonly used online crowd sourcing platforms, in enumerating brick-and-mortar marijuana dispensaries across the entire state of California. California is the most populous state with the longest history of medical marijuana legalization in the US. In November 2016 California legalized recreational marijuana and in January 2018 California initiated retail sale of recreational marijuana in dispensaries. California now has the largest legal marijuana market in the world,rolling tables grow with sales rising from $2.5 billion in 2018 to $3.1 billion in 2019 . Although California allows delivery services, in this study, we concentrated only on brick-and-mortar marijuana dispensaries because delivery-only providers do not have storefronts to showcase and promote products. In addition, the wide geographic coverage of delivery services contributes little variation in marijuana availability at neighborhood level. We offered a protocol for identifying dispensaries that can be replicated in other large geographic regions with marijuana retail sales. We aimed to answer two research questions. The first question was to what extent online crowd sourcing platforms are valid in enumerating licensed brick-and-mortar dispensaries. The motivation was that many dispensaries in California operated without a license. Even for licensed dispensaries, how they operate in practice may not agree with what was approved in the license. Findings from the first question will provide quantifiable evidence on the level of agreement between state licensing directory and online crowd sourcing platforms, add surveillance data point on the operation of unlicensed dispensaries, and inform policymakers regarding the validity of using online crowd sourcing platforms as alternatives when state licensing directory is not publicly accessible or licensing information is inadequate . The second question was to what extent state licensing directory and online crowd sourcing platforms are valid in enumerating the universe of active brick-and-mortar dispensaries. The motivation was that a single data source may not capture all active dispensaries in California and the information in a data source may not agree with how dispensaries operate in practice. Findings from the second question will provide quantifiable evidence on the strengths and weaknesses of each data source, inform surveillance and research regarding how to best strategize data use when resources are limited, and demonstrate the need for combining multiple data sources and verifying information to obtain the universe of dispensaries in a large geographic area. Because recreational-only, medical-only, and recreational & medical dispensaries co-existed in California, we also assessed validity measures by dispensary category.
Dispensaries may tend to promote themselves on online crowd sourcing platforms in larger counties with keen competition, we hence further assessed validity measures by county population size. From May to July 2019, eight trained research associates aged 21 or older called the 2,121 unique businesses to verify their street address, operation status, category of business, and presence of storefronts . Each call took fewer than 5 minutes on average. As commonly done in compliance check inspections of tobacco product retailers, the research associates did not reveal the research purpose of the calls. Instead, they identified themselves as interested customers who were considering a visit in near future. To determine dispensary category, researchers asked if a doctor’s recommendation or a patient registration card was required to enter the dispensary and make purchase. An affirmative response indicated the dispensary category to be medical only. If the response was negative yet customers with a doctor’s recommendation or a patient registration card were eligible for reduced tax rates, the dispensary was categorized as recreational & medical. The remaining dispensaries were considered to be recreational only. Up to five calls were made to each business in different business hours and/or on different business days to determine operation status. If a dispensary could not be reached after five call attempts, researchers checked its recent online activities on Weedmaps, Leafly, Yelp, and Google Map Reviews. If the dispensary had any online activity within the past month , it would be considered active1 . After removing inactive businesses, businesses not selling marijuana, and businesses without storefronts during the verification procedure, the 2,121 unique records were reduced to 826 businesses . These 826 dispensaries constituted the call-verified, combined database of active brick-and-mortar dispensaries in California. Validity statistics, including sensitivity, specificity, positive predictive value , and negative predictive value were computed for each of the four secondary data sources when applicable. Definitions and calculations were described in Technical Note S1. To compute validity statistics, a gold standard must be defined that can identify the “true positive” and the “true negative”. However, it is infeasible in this study due to budget and time constraints for a statewide census. Two gold standards were adopted alternatively to answer the two research questions. To answer the first question regarding the validity of online crowd sourcing platforms in enumerating licensed brick-and-mortar marijuana dispensaries, the first gold standard was whether a record was listed in the BCC state licensing directory . To answer the second question regarding the validity of state licensing directory and online crowd sourcing platforms in enumerating active brick-and-mortar marijuana dispensaries, the second gold standard was whether a record was included in the call-verified, combined database of active dispensaries . We must also define a test that can identify the “positive test” and the “negative test” in validity statistics calculations. Two tests were conducted. The first test was whether a record was present in a given data source after online data cleaning . We used this test to examine the validity of using a single data source with simple online data cleaning for dispensary identification, an approach requiring moderate resources. The second test was whether a record passed call verification; in other words, whether the record was verified to be an active brick-and-mortar dispensary . We used this test to examine the validity of using a single data source with simple online data cleaning plus call verification for dispensary identification, an approach requiring much more resources. To illustrate these validity statistics in the context of this study, we provide an example below . In this example, the data source of interest is Weedmaps, the gold standard is whether a record on Weedmaps was present in the BCC state licensing directory, and the test is whether a record was present on Weedmaps after online data cleaning. Sensitivity measures the probability of a record present on Weedmaps conditional on the record being included in the BCC directory, calculated as the number of records that were present on both Weedmaps and the BCC directory divided by the number of records present on the BCC directory. Specificity measures the probability of a record absent on Weedmaps conditional on the record being excluded from the BCC directory, calculated as the number of records that were neither present on Weedmaps nor present on the BCC directory divided by the number of records excluded from the BCC directory.