Cannabidiol (CBD) is one of more than 113 identified cannabinoids derived from the cannabis plant. CBD is abundant in the hemp plant, a variety of the Cannabis Sativa species that is bred for industrial uses and does not contain the main psychoactive compound in cannabis, ∆⁹-tetrahydrocannabinol (Delta-9-THC). While Delta-9-THC-containing cannabis products remain illegal at the federal level in the United States, the passage of the 2018 Farm Bill provided a legal justification for the manufacturing and sale of “CBD Products” (those containing hemp-derived CBD and ≤0.3% Delta-9-THC) in all 50 US states [1]. Since this time, CBD products have become incredibly popular and so diverse that they can be incorporated into almost every aspect of a consumer’s lifestyle, including bath soaps, candy, cosmetics, drink mixers or tincture, food, medicinal products (e.g., pain pills or sleep aids), pet products, sex lubricants, cigarettes, and vaporizers [2,3].

CBD products have achieved their popularity at least in part because CBD has been widely touted as a cure-all. For example, one cannabis brand MedMen^® has claimed that CBD can treat acne, anxiety, opioid addiction, pain, and menstrual problems [4]. More recently, CBD has even been promoted as a treatment for COVID-19 in popular news articles [5]. However, the only CBD therapy approved by the US Food and Drug Administration (FDA) is Epidiolex^®, a highly purified form of CBD prescribed to treat Lennox-Gastaut syndrome, Dravet syndrome and tuberous sclerosis complex (3 rare forms of childhood epilepsy) [6,7]. While the pharmacological profile of CBD suggests that additional therapeutic applications of CBD could eventually be approved by the FDA, the public may already perceive that CBD is an effective therapeutic for many health conditions that it may never be approved to treat [8]. This is of particular concern when patients are substituting CBD for other proven effective treatments–prolonging illnesses that could otherwise be alleviated [9].

While commonly dismissed as a benign consumer product, CBD is not devoid of health risks. Known side effects include liver damage, male reproductive toxicity, nausea, vomiting, drug interactions, sedation, and somnolence [6,10]. Moreover, while CBD does not produce the same euphoric experience that Delta-9-THC produce, it interacts with the central and peripheral nervous systems in ways that classify it as psychoactive [11]. For example, CBD is already approved in prescription form to treat certain childhood seizures and other applications are being pursued for the potential to treat anxiety and addiction [12,13]. Given these psychoactive properties, it is possible that CBD could impact individuals’ abilities to operate motor vehicles, but this has not been well studied [14]. Many other health risks and drug interactions that may be associated with adverse events or diminished efficacy of approved therapies could also exist, but in reality, very little is known about the risks of short- or long-term use.

The marketplace of CBD products has also created regulatory complexities that specifically overlap with tobacco regulation and have had public health impacts. CBD and nicotine can be used interchangeably in some vaping devices. This interchangeability can muddle efforts to pin-point culprit products during outbreaks related to vaping products, such as occurred during the e-cigarette or vaping-associated lung injuries (EVALI) outbreak, when many cases used a combination of CBD, nicotine, and Delta-9-THC in their vapes [15]. While at the federal level in the United States, e-cigarette manufacturers are now required to submit product applications to the FDA before they can market and distribute in the United States, the FDA framework for CBD does not require such applications [4]. Without such quality assurance standards, CBD products can be mislabeled and include Delta-9-THC [16] and adulterated CBD products (primarily CBD vapes) have led to mass poisonings [17]. The interchangeability of vaping products can also create loopholes in regulation. For example, one CBD vape brand bluum [18] exploits a loophole in nicotine-vaping policy by producing JUUL-compatible mango-, berry-, and mint-flavored CBD pod cartridges, even though these flavors were recently prohibited from pod-based e-cigarettes like JUUL in the US because of their popularity among youths [19]. Globally, some vape shops have also directly responded to shocks on the marketplace for vaping products by adapting to carry CBD products. For instance, when vaping was temporarily banned in South Africa as a part of COVID-19 emergency response efforts, many vape shops circumvented this ban by switching their product offerings to include CBD e-liquid and vapes [20].

In spite of these challenges and health risks, very little is known about how vape shops (i.e., retailers that sell e-cigarettes/vapes and related components) have responded to the growing popularity of CBD. One in-store surveillance study conducted by Kong et al. found that 6% of vape shops and 47% of combined vape and head shops (i.e., shops that sell drug paraphernalia) in New Hampshire sold CBD- and/or Delta-9-THC-containing products, despite neither CBD- nor Delta-9-THC-containing products being legal in the state at the time [21]. Another in-store surveillance of vape shops across six metropolitan statistical areas (MSAs; Atlanta, Boston, Minneapolis, Oklahoma City, San Diego, and Seattle) conducted by Berg et al. in 2018 identified that 43% of vape shops sold CBD e-liquids and 23% sold other CBD-containing products [22]. An additional phone-based survey of vape shop owners/managers across the same MSAs further substantiated this finding, with 44% of owners/managers reporting that their shops sold CBD e-liquids [23]. Notably, all current surveillance has been limited by its focus on brick-and-mortar retailers, which may not mirror the e-commerce marketplace. Of specific concern with e-commerce is preventing youth purchases, as online retailers have a more limited ability to verify the age of consumers who mail-order their products and youth are often able to successfully bypass age verification to purchase tobacco products including e-cigarettes [24,25].

In this manuscript, we provide e-commerce surveillance on the availability and promotion of CBD products among vape shops returned in typical internet searches indicative of shopping for vaping products. We utilized an existing method that has been previously used to study the availability of mail-order marijuana delivery using the Google search engine [26]. Specifically, we executed a series of Google searches and then reviewed the content of those searches to identify vape shops and further study their product offerings and marketing. Our searching strategy was designed to capture general searches indicative of shopping for vaping products. In a previous analysis of the queries we use, we estimated that there were 30.3 million vape shopping Google searches in 2019 and that the trajectory and growth in these queries followed the trajectory and growth in unit sales of e-cigarettes and had periodicities and holiday patterning that follow the purchasing of other consumer goods [27]. We focused our analysis on the first two pages of search results, because over 80% of Google searchers click a link on the first two pages, with as many as 42% selecting the first link [28]. Among websites returned in this search, we conducted a content analysis to determine whether CBD products could be mail-ordered from the returned website. Since CBD products can come in numerous forms and not just vapes (e.g., capsules, edibles, topicals, and tinctures), we documented the forms of CBD that vape shops allowed visitors to mail-order on their websites. Finally, because CBD products have been marketed extensively with unsubstantiated health claims [4,9], we also conducted a content analysis to determine whether the vape shops made any health claims about CBD products.