The utilization and delivery of safer smoking practices and services: a narrative synthesis of the literature
Harm Reduction Journal volume 20, Article number: 160 (2023)
Providing sterile drug smoking materials to people who use drugs can prevent the acquisition of infectious diseases and reduce overdose risk. However, there is a lack of understanding of how these practices are being implemented and received by people who use drugs globally.
A systematic review of safer smoking practices was conducted by searching PubMed, PsycInfo, Embase for relevant peer-reviewed, English-language publications from inception or the availability of online manuscripts through December 2022.
Overall, 32 peer-reviewed papers from six countries were included. 30 studies exclusively included people who use drugs as participants (n = 11 people who use drugs; generally, n = 17 people who smoke drugs, n = 2 people who inject drugs). One study included program staff serving people who use drugs, and one study included staff and people who use drugs. Sharing smoking equipment (e.g., pipes) was reported in 25 studies. People who use drugs in several studies reported that pipe sharing occurred for multiple reasons, including wanting to accumulate crack resin and protect themselves from social harms, such as police harassment. Across studies, smoking drugs, as opposed to injecting drugs, were described as a crucial method to reduce the risk of overdose, disease acquisition, and societal harms such as police violence. Ten studies found that when people who use drugs were provided with safer smoking materials, they engaged in fewer risky drug use behaviors (e.g., pipe sharing, using broken pipes) and showed improved health outcomes. However, participants across 11 studies reported barriers to accessing safer smoking services. Solutions to overcoming safer smoking access barriers were described in 17 studies and included utilizing peer workers and providing safer smoking materials to those who asked.
This global review found that safer smoking practices are essential forms of harm reduction. International policies must be amended to help increase access to these essential tools. Additional research is also needed to evaluate the efficacy of and access to safer smoking services, particularly in the U.S. and other similar countries, where such practices are being implemented but have not been empirically studied in the literature.
Harm reduction is a collection of concepts and strategies that can be used to reduce adverse health consequences associated with drug use . Harm reduction strategies can be conceptualized as a continuum of approaches from safer drug use practices to abstinence, with an underlying core ethos of a desire to meet people where they are at. As an alternative to the “zero tolerance” abstinence-only models of addiction treatment, the harm reduction model recognizes that abstinence may not be a desirable or achievable outcome for all people who use drugs . Thus, practical strategies are necessary to reduce health-related harms associated with drug use (e.g., viral transmission of Human immunodeficiency virus (HIV) and Hepatitis C (HCV) through shared drug use equipment, fatal and nonfatal overdose), rather than exclusively targeting drug consumption itself [3,4,5,6,7].
Historically, harm reduction principles are actualized when individuals and groups take sometimes illegal measures to protect their communities. Once systemic structures recognize the value in these practices, they might become decriminalized and widely supported by public health institutions. As an example, supervised consumption sites have been created; these are spaces where individuals can use drugs in a sterile and monitored space with access to supplies and care. Legalized in certain European nations, Canada, and Australia, supervised consumption sites in the U.S. operated quietly and against the law . With increased evaluations published globally, and within the country on unsanctioned supervised consumption sites , we see increased receptiveness in academic circles. In the U.S., this illicit practice of providing safe spaces to consume drugs recently gained popular ground with Rhode Island becoming the first state to legalize supervised consumption sites , and OnPoint in New York City opening the first SCS in the U.S. . Other recent innovations in public health lifted up by the advocacy of people who use drugs include drug checking and safer smoking initiatives.
Harm reduction has traditionally focused on mitigating the risks of injection drug use (IDU) [7, 12,13,14,15] by providing access to sterile syringes via syringe service programs (SSPs) , and, more recently, supervised injection facilities [14, 17,18,19,20]. SSPs and the concept of risk reduction were adopted as public health strategies by several countries in the 1980s (e.g., Australia, Brazil, Denmark, Netherlands, some states in the U.S., United Kingdom) in the midst of the HIV/AIDS epidemic [7, 21]. In 1986, the World Health Organization was the first major international body to accept and endorse harm reduction , marking an influential shift in historically punitive global drug policies . Other international bodies such as Joint United Nations Programme on HIV/AIDS, United Nations Office on Drugs and Crime, International Drug Policy Consortium, and United Nations Development Programme have joined in their endorsement of harm reduction .
Harm reduction services were originally focused on reducing adverse health outcomes for people injecting heroin . Smoking drugs also carry health risks, including pulmonary distress [13, 25], COVID-19 , overdose (OD) , burns and lacerations on the lips [27, 28], tuberculosis , HIV, and HCV [3,4,5]. In order to mitigate these risks, some countries have led the way in developing safer smoking programs. Indeed, as early as the 1970s, informal drug consumption rooms, primarily inhalation-oriented spaces, were operating in the Netherlands [19, 20]. By 1999, Hamburg, Germany, operated 15 supervised inhalation spaces, and Switzerland introduced inhalation spaces by 2001 . Similarly, in 2000, the Safer Crack Use Coalition of Toronto, Canada, began distributing ‘safer crack use kits’ to advocate for people who smoke drugs , a practice adopted by the Toronto city government in 2005 and recommended by Ontario, Canada in 2006 as ‘best practices’ for harm reduction programs .
Despite the increasing availability of safer smoking services internationally, harm reduction efforts targeting noninjection drug use have received comparatively less attention than those for IDU [15, 24, 27, 31, 32], even as health and social consequences associated with smoking substances are becoming better understood. People who smoke drugs are often characterized as a hard-to-reach population for social service programs  because these programs have traditionally been focused on the provision of supplies (e.g., syringes, naloxone) to people who inject drugs . The distribution of safer smoking supplies (e.g., sterile pipes, stems, filters) by harm reduction organizations creates an opportunity to engage people who smoke drugs who may not otherwise access harm reduction programming [24, 30, 34]. Further, in 2019, the United Nations Office on Drugs and Crime called for the expansion of programs for people who use stimulants, particularly those providing safer smoking education and supplies .
The ongoing removal of drug policies that criminalize the provision of safer smoking materials in countries around the world [13, 24, 35], together with international calls for the expansion of safer smoking services [15, 21, 23, 31], has opened the door for the widespread implementation of these services in many regions. However, the extent to which safer smoking services are being provided globally is not well-understood. Moreover, synthesized data on access to and feasibility, acceptability, and efficacy of safer smoking harm reduction services are lacking in the literature. To close this research gap, we conducted a systematic review to summarize the available literature on (1) whether and how safer smoking interventions have been incorporated into harm reduction initiatives; (2) whether people who use drugs have access to safer smoking materials and services; (3) whether and how people who smoke drugs engage in safer smoking practices; and (4) the extent to which safer smoking practices and the availability of safer smoking services reduce the health-related risk of smoking drugs.
The PRISMA reporting guidelines were used in the development of this protocol-driven report. The protocol was registered in PROSPERO: International Prospective Register of Systematic Reviews (ID: CRD42022345289).
Inclusion and exclusion criteria
To be eligible for inclusion in this review, articles must have contained one or more of the following search terms from set A or B (see "Appendix"). Articles had to be written in English and published in a peer-reviewed journal as an original article. All articles were required to be based on studies involving human subjects. This review excluded other reviews, dissertations, conference abstracts and presentations, and commentaries, as well as studies that reported on harm reduction practices that did not explicitly discuss safer smoking services.
The authors generated a set of terms that aligned with the focus of the review (e.g., safer smoking, harm reduction). The first and second authors then consulted an expert librarian at Boston University, who helped design and conduct the electronic search strategy (See "Appendix"). To identify eligible studies, PubMed, PsycInfo, and Embase were searched from inception or the availability of online manuscripts through December 2022. Exact search terms for these databases were determined with preliminary inquiries and refined as needed. In PubMed, tiab (limiting to search terms to title or abstract) and mesh (medical subject headings) searches were implemented. A hand search of the bibliographies of retrieved articles was also conducted.
The initial search returned 214 articles. The first and second authors (AT and CA) examined abstracts and titles from the initial search to identify studies that appeared to meet the inclusion criteria. The full article was then obtained for all studies appearing to meet inclusion criteria or in instances where there was insufficient information from the title, keywords, and abstract to make a clear decision. In cases where the two reviewers disagreed regarding the eligibility of an article for inclusion, a third reviewer (ZG) was consulted. From the original 214 articles identified via the electronic database search, 23 articles were eligible for inclusion. Nine additional articles were identified by reviewing the bibliographies of the 23 articles. In total, 32 articles were eligible and included in this review (Fig. 1). All included studies relied on self-report. Many of these studies included strong controls for confounders, but due to the early stage of research surrounding safer smoking and harm reduction, all studies fitting inclusion criteria were included regardless of methodological rigor. Due to the early stage of this topic, the authors did not conduct a formal assessment of methodological quality as all included studies were observational and represent low-quality formative evidence. Nonetheless, methodological limitations are reported in the text where relevant.
Data extraction and analysis
The first and second authors (AT and CA) extracted the following study-level data from the 32 eligible studies using a data collection spreadsheet that included the following domains: Authors, Title, Location/Setting, Participant Characteristics (e.g., people who use drugs or harm reduction organization staff, gender, age group), Study Type (qualitative, quantitative, mixed methods), Main Substance of Focus (e.g., crack cocaine, heroin, any illegal substance), and Study Results.
The 32 articles in this review were then organized using a narrative synthesis approach . Thematic analysis was used in the process of narrative synthesis to develop codes and themes based on the selected studies . The first and second authors (AT and CA) developed the initial set of codes. Codes were then discussed with all coauthors and any recommended changes were discussed and revised until full agreement was reached. The first and second authors then applied the codes to all of 32 studies. After completing the thematic analysis, the codes were then collapsed into five overarching themes. The relevant themes from each study were then extracted and added to the data collection spreadsheet. The Authors, Title, Location, Participant Characteristics, Study Design, Main Substance of Focus, Key Findings, and Overarching Themes for each study are presented in Table 1.
Figure 1 depicts the study selection process. In total, 32 articles were eligible and included in this review (Table 1). All 32 articles were observational, of which, 18 employed quantitative methods (14 surveys; 5 serology, 1 secondary data collection), ten employed qualitative methods (six in-depth interviews; two focus groups), and four utilized mixed methods. Overall, 25 of the studies were one-time cross-sectional studies, and seven were longitudinal studies.
The studies were published between 2005 and 2021. All included studies were conducted outside of the U.S., with the majority coming from Canada (n = 27) and 1 each coming from Brazil, England, Germany, Indonesia, and Mexico.
Overall, 30 studies exclusively included people who use drugs as participants (n = 11 people who use drugs; generally, n = 17 people who smoke drugs, n = 2 people who inject drugs). One study included harm reduction program staff serving people who use drugs, and one study included staff and people who use drugs. Several studies examined specific substance use patterns among people who use drugs, including the use of crack cocaine, methamphetamine or multiple substances. The majority of the studies (n = 20) focused on crack use, six on any substance smoked, three on any illegal drug used, two on methamphetamine use, and one each on methamphetamine, opioids, and heroin.
Smoking as a form of harm reduction
One quantitative study with people who use drugs examined both the social and behavioral factors associated with smoking opioids . The researchers found that when adjusting for smoking opioids, participants who used methamphetamine had 6 times higher odds of smoking opioids (adjusted Odds Ratio (aOR) = 6.48; 95% confidence interval (CI) 3.51–11.96, p < 0.01) than those who did not use methamphetamine. Other factors associated with the increased odds of smoking opioids include living in a small urban/rural area (ref = median/large urban area; aOR = 2.41, 95% CI 1.27–4.58, p = 0.01), being a woman (ref = man; aOR 1.84, 95% CI 1.03–3.30, p = 0.04), being under age 30 (ref = 50 and over; aOR = 5.41, 95% CI 2.19–13.40, p < 0.01), between 30 and 39 years of age (ref = 50 and over; aOR = 2.77, 95% CI 1.33–5.78, p = 0.01), using drugs alone yes vs. no; aOR 2.98, 95% CI 1.30–6.83, p = 0.01), and having naloxone (yes vs. no; aOR = 2.01, 95% CI 1.08–3.72, p = 0.03) .
Five qualitative studies [38,39,40,41] and two quantitative studies [42, 43] examined how smoking as opposed to injecting substances is a form of harm reduction. Specifically, in two qualitative studies [40, 44], participants who smoked drugs as opposed to injected drugs reported feeling more in control of their lives and able to take care of themselves and their needs, such as their health and housing. Further, in one of the qualitative study with people who smoke drugs , a participant explicitly noted that she felt more socially and fiscally stable since ceasing injecting drug use. Participants in another qualitative study with women who smoke drugs  expressed a similar preference for smoking as opposed to other modalities. When describing their partiality to smoking over injecting, across studies, many participants reported a fear of needles/syringes and acknowledged that although there was still some risk of overdose when smoking drugs, smoking carried less overdose risk than injecting drugs. In addition to acknowledging the reduced risk for overdose with smoking as opposed to injecting, people who use drugs in one qualitative study  described smoking as a way to reduce HIV and HCV acquisition risk, compared to injecting. Comparably, 58.9% of the 112 people who use drugs who participated in one quantitative study  indicated that they preferred smoking with foils (heating heroin on a piece of aluminum foil and inhaling the vapor through a straw) over injecting as they believed it to be healthier. Additionally, 35.7% of people who use drugs in the same study reported that smoking drugs (instead of injecting) reduced their risk of HIV or HCV, and 33.9% reported that smoking helped to reduce their risk of overdose.
Sharing of smoking materials
Although participants in many studies reported that smoking carried fewer health risks than injecting drugs, many people who use drugs in the included studies reported sharing smoking materials, which can increase individuals’ risk of disease acquisition and transmission. Indeed, 23 studies included data on the prevalence of and rationale for the sharing of smoking materials [35, 40,41,42, 44,45,46,47,48,49,50,51,52,53,54,55,56,57,58,59,60,61,62].
Prevalence of sharing smoking materials was reported in five studies. In one quantitative study with people who use drugs, 88% of the 567 participants reported sharing crack smoking materials . Another quantitative study with 149 people who smoke drugs found that over half (56.38%) of their participants had loaned, borrowed or shared pipes . Similarly, in a quantitative study with people who use drugs, 47.3% of the 503 participants had shared a crack pipe in the last 6 months . Just under half (48.57%) of the 1085 people who use drugs in a quantitative study reported sharing materials . One study found the sharing of materials differed somewhat by gender such that 61% of women and 55% of men in the study reported sharing smoking materials in the 6 months prior to participating in the study .
Several studies with people who use drugs and people who smoke drugs identified a myriad of reasons for why people who use drugs reported shared smoking materials. Participants in one qualitative study with people who use drugs  and two qualitative studies with people who smoke drugs [45, 53] provided economic reasons for sharing materials, such as building a “push” of crack resin (i.e., allowing small amounts of resin from previous crack smoking sessions to accumulate to be smoked again). Participants in another qualitative study with people who smoke drugs reported concerns about the high price of pipes . Further, participants in one qualitative  and one quantitative  with people who smoke drugs spoke of challenges in finding new materials to use in the context of limited resources. Additionally, participants in one qualitative  and one mixed methods  study with people who use drugs, and a qualitative study with people who smoke drugs  also reported that they do not always carry their own pipes.
Sharing for social reasons was also commonly reported. Specifically, across studies using qualitative approaches [39, 41, 44, 51,52,53] people who use drugs and people who smoke drugs reported that crack and methamphetamine smoking are viewed as social activities and beneficial to positive group dynamics such as protection of others within the group among communities of people who use drugs.
Two quantitative, one qualitative and one mixed methods study examined factors associated with pipe sharing [48, 50, 63, 64]. One study  used logistic regression and found that the following sociodemographic factors were significantly and positively associated with pipe sharing: homelessness; (yes vs. no; aOR = 1.87, 95% CI 1.43–2.44, p < 0.001), regular employment; (yes vs. no; aOR = 1.53, 95% CI 1.15–2.04, p = 0.003), daily crack smoking; (yes vs. no; aOR = 1.37, 95% CI 1.01–1.85, p = 0.043), crystal meth use; (yes vs. no; aOR = 2.04, 95% CI 1.11–3.75, p = 0.022), encounters with police; (yes vs. no; aOR = 1.42, 95% CI 1.01–1.99, p = 0.043), having unprotected sex; (yes vs. no; aOR = 1.95, 95% CI 1.47–2.58, p < 0.001). Another study that employed logistic regression (62) found that sharing a crack pipe was significantly associated with the increased odds of smoking crack in public; (yes vs. no; OR = 1.68, 95% CI 1.26–2.25, p < 0.001) reported sharing pipes. Two additional studies [49, 57] examined global differences in the sociodemographic characteristics of those who shared pipes, with one study , finding that a significantly higher proportion of people living in a rural area as opposed to a major urban area shared pipes (p < 0.01). The other study found that compared to those who did not share pipes, a higher proportion of those who reported sharing pipes also reported selling drugs for sex, experienced burn or lesions, had a pipe explode, and used broken pipes . Additionally, in three quantitative studies with people who use drugs [47, 60, 61] challenges accessing pipes was significantly and positively associated with the increased odds of sharing pipes with others (yes vs. no; aOR = 1.58, 95% CI 1.13–2.20; p = 0.007 ; aOR = 2.19, 95% CI 1.42—3.37; p < 0.01 ; aOR = 1.74, 95% CI 1.31–2.32, p < 0.01 ).
Delivery and utilization of safer smoking services
Utilization of smoking services
In exploring the utilization of smoking services, the harm reduction programs featured across ten of the included studies were described as providing a variety of materials to their clients [35, 42, 43, 45, 50, 56, 58, 63,64,65]. Specifically, as shown in Fig. 2, harm reduction organizations provided glass pipes, rubber mouthpieces, brass tobacco screens, wooden push sticks, condoms and descriptive literature.Footnote 1
Eight of the studies included in this review evaluated safer drug smoking initiatives [42, 43, 50, 56, 63, 65]. In a quantitative study with 80 program staff evaluating drug user health programs across Canada, participants reported that the majority of programs provided education on risk reduction for smoking (76%), including education on risks from improvised equipment (75%), and how to use safer smoking equipment (72%) . Several studies also described how safer smoking programs were modified over time to meet the needs of people who use drugs. In one mixed methods study with eight harm reduction staff , upon receiving feedback that most participants shared smoking materials, harm reduction staff modified the materials they distributed to people who use drugs by including a mouthpiece in their safer smoking kits.
Access to and feasibility and acceptability of safer smoking services
Overall, several studies examined the anticipated and actual utilization of safer smoking services by people who use drugs with (n = 443)  and without (n = 437)  experiences accessing these services. Indeed, willingness to use safer smoking materials or safer smoking facilities’s ranged from 27.99%  to 69%  across studies of people who use drugs. Additionally, in both previously mentioned quantitative studies with people who use drugs[35, 48], found that compared to those who did not share materials, those who shared pipes had significantly greater odds of reporting a willingness to use safer smoking facilities (aOR = 1.64, 95% CI 1.02–2.64, p = 0.042 , aOR = 2.5, 95% CI 1.86–3.40, p = 0.006 ). Further, across three studies [35, 48, 66], additional factors associated with willingness to use a safer smoking facility included living in an HIV epicenter (yes vs. no; aOR = 1.85; 95% CI 1.14–2.97, p = 0.011), working in the sex trade (yes vs. no; aOR = 2.24, 95% CI 1.32–3.80, p = 0.003) , daily noninjection crack use (yes vs. no; aOR = 1.63, 95% CI 1.08–2.48, p = 0.021), binging crack (yes vs. no; aOR = 2.16, 95% CI 1.39–3.12, p = 0.014), ever using drugs in a hospital (yes vs. no; aOR = 1.89, 95% CI 1.31–2.73, p < 0.001) , current injection drug use (yes vs. no; aOR = 1.72, 95% CI 1.09–2.70, p = 0.019), having equipment confiscated or broken by the police (yes vs. no; aOR = 1.96; 95% CI 1.24–2.85, p = 0.003), smoking crack in public (yes vs. no; aOR = 2.48, 95% CI 1.65–3.27, p = 0.002), and inhaling Brillo/getting burned due to rushed crack use (yes vs. no; aOR = 4.37, 95% CI 2.71–8.64, p < 0.001) . In one quantitative study with people who use drugs , difficulty finding new crack pipes was negatively associated with willingness to use a safer smoking facility (yes vs. no; aOR = 0.51; 95% CI 0.30–0.86, p = 0.013).
Notably, ten studies [42,43,44, 50, 56, 63,64,65, 67, 68] found that people who use drugs were already utilizing safer smoking materials and programs, some at very high levels of utilization. Specifically, one quantitative study with people who smoke drugs found that 80% of participants accessed the safer smoking program being evaluated within 1 month of the program opening . Similarly, in a quantitative study with people who smoke drugs, 98% of participants reported using the glass stems and pipes in the safer smoking kits that were distributed at a harm reduction organization in Canada .
In 11 of the included studies [40, 41, 44, 45, 51, 54, 55, 59, 61, 63, 64], participants who used drugs reported multiple barriers to accessing safer smoking materials. Across studies, lack of resources was cited as a common barrier to people who use drugs’s ability to access safer smoking harm reduction materials. These resources included lack of funding for programs to give out safer smoking equipment , as well as not having enough sterile materials in circulation that participants were able to access [41, 51, 55, 59], fears of harassment by the police and/or violence due to police interaction was another common barrier to accessing safer smoking materials [55, 61, 63, 64]. For example, in one mixed methods study with people who smoke drugs, participants commonly reported having their pipes confiscated by police or taken and immediately broken .
In some cases, even when safer smoking materials were being offered in a specific community, people who use drugs could not consistently or easily access them. For example, one qualitative and one mixed methods studies with people who smoke drugs [51, 64] and one quantitative study with people who use drugs  found that the limited hours of operations of harm reduction programs were a barrier to accessing safer smoking materials when needed. Other barriers experienced by research participants included a lack of safe spaces in which to smoke [40, 44], poor experiences with smoking materials (e.g., not liking using screens) , high staff turnover , and a lack of demand from participants for safer smoking materials .
Notably, three qualitative and one mixed methods studies found that having peer staff working in harm reduction agencies connect with, and distribute materials to, people who use drugs was crucial to client engagement with services [45, 54, 58, 63]. Further, in one of these studies in which both staff and clients participated, people who use drugs reported that they felt safer using harm reduction services when they were distributed by peers with a history of drug use .
Preliminary efficacy of safer smoking services
Overall, there were six studies that assessed the impact of safer smoking services on health behaviors and wellbeing. Five program evaluation studies found that participants’ use of smoking equipment, sometimes over injecting, increased as materials were provided. A quarter of participants in one quantitative study with people who use drugs reported that they were smoking more since there was sterile equipment made available to them . In another quantitative study with people who smoke drugs , the proportion of participants who reported always or almost always using a Pyrex pipe (a preferred material due to the higher durability material compared to regular glass pipes  increased significantly from 7.0 to 27.3% (p = 0.002). Additionally, in a quantitative study with people who use drugs , all participants felt that the single use foils they received were beneficial to have at their harm reduction program. Participants in a quantitative study with people who use drugs provided context as to why participants preferred smoking with single use foils; 58.9% of participants said that they preferred smoking with the foils over injecting because it was healthier, 35.7% because of the reduced risk of HIV/HCV, and 33.9% to avoid overdose .
Four studies evaluated interventions to reduce the sharing of smoking materials [50, 56, 58, 59]. In two quantitative studies with people who smoke drugs, the researchers found that providing new pipes to people who use drugs resulted in decreased sharing of smoking equipment over the study period [50, 56]. Additionally, in a quantitative study with people who use drugs, participants who received safer smoking materials not only reported reducing their injection drug use behaviors but also reported bringing back safer smoking materials to their friends and other people in their drug use network .
Only one study directly assessed the impact of safer smoking programs on health outcomes. Specifically, one quantitative study with 1718 people who smoke drugs who had received safer crack smoking materials found that participants’ health issues (e.g., burns, sores, coughing blood) related to smoking crack declined by 18.5% over the study period (December 2005–November 2014) .
This is the first review, to our knowledge, to synthesize the available literature on safer smoking practices, and safer smoking service delivery and utilization. Findings show that smoking drugs is a popular route of administration among people who use drugs and evidence from this review suggests that expanding access to safer smoking within harm reduction services is crucial to risk mitigation. Within the studies included in this review, most study participants, including people who smoke drugs, peers, and service providers, believed safer smoking services to be a necessary harm reduction intervention, especially when considered in relation to existing safer injection services [39, 40, 42,43,44, 51, 54, 56, 63, 64, 67, 68]. Further, across studies, people who use drugs reported a high willingness to utilize these services, and in places where services were offered, many studies reported high utilization of safer smoking services. Additionally, although efficacy data were limited, across studies, people who use drugs reported decreasing their injection drug use in favor of smoking, reducing the sharing of smoking equipment, and in some cases improved health outcomes (e.g., decreased burns and cuts). Despite the clear benefits of safer smoking practices, some people who use drugs and service providers reported ongoing barriers to accessing and delivering these services, respectively. Findings underscore the need for ongoing research and structural interventions to increase access to safer smoking programs and reduce drug use related morbidity and mortality.
This is a burgeoning area of research, which we expect to grow and evolve as policies shift, more funding becomes available for the inclusion of safer smoking kits into harm reduction service offerings, and the benefits of these practices become more well known. In fact, since the time that this search was conducted, a new study was published in May 2023 that showed high interest in using safer smoking materials, with participants believing it would reduce their injection use of drugs. As additional studies are published, including those that are based on higher quality evidence, we anticipate a need to update this review in future years .
Despite evidence that smoking has benefits over injecting [39, 40, 42,43,44, 51, 54, 56, 63, 64, 67, 68], across studies, people who use drugs report programs providing safer smoking materials are a minority among harm reduction organizations globally. Ongoing work is needed to incorporate safer smoking materials into the services provided by existing harm reduction organizations. The studies reviewed here provide evidence of the presence of peer workers who are part of these communities as people with lived experience and found peers to be integral in engaging people who use drugs and assisting them with changing their practices. Further outreach to educate people who use drugs about smoking as a harm reduction practice is necessary, including the nuanced benefits and risks associated with it.
In addition to program adaptations, there is also a need for additional research related to safer smoking services. Specifically, the vast majority of studies included in this review focused on crack smoking, demonstrating the need to better understand how people smoke drugs other than crack. Such data are essential to learning how to adapt safer smoking equipment in order to reduce smoking related harms and improve the acceptability of the safer smoking materials provided to people who smoke drugs.
Notably, none of the studies included in this review were based in the U.S. or other countries where smoking is banned. In the U.S. for example, Alaska is the only state that has amended its constitution to remove safer smoking materials from their definitions of ‘paraphernalia’ or protect individuals from criminal charges for possession of safer smoking materials if they were obtained from an authorized harm reduction organization, despite evidence that these types of possession laws can further harm people using substances . These policy shifts have enabled harm reduction organizations in several states to begin disseminating safer smoking materials; however, these programs have yet to be formally evaluated and documented in the literature. As safer smoking services become more widely available in the U.S. and worldwide, it is essential that efforts be made to support community programs in building the infrastructure to rigorously evaluate the impact and efficacy of safer smoking service delivery. High-quality data on the feasibility, acceptability, and efficacy of these programs in U.S. and similar country’s drug use contexts and beyond is necessary to secure sufficient allocation of supportive resources for safer smoking materials delivery in harm reduction, community, and medical settings as well as identify intervention targets aimed at improving access to and utilization of safer smoking services.
Canadian research was the main source for studies included in this review. Canada has been distributing safer smoking materials since the early 2000’s and as such, researchers have had a plethora of material to study. Smoking is the most common route of administration in some provinces of Canada , and in response to the increased overdose deaths attributed to smoking opioids, the government took steps to reduce barriers to safer smoking resources by authorizing some safe consumption sites to offer inhalation spaces. Thus, the research coming out of Canada was most relevant to this review.
Finally, although some U.S. states or districts have decriminalized the provision of drug use paraphernalia , ongoing policy shifts are necessary to ensure continued access to these essential tools for people who use drugs. Specifically, under current policy, U.S. harm reduction agencies receiving financial assistance from federally funded grants are not able to purchase pipes or stems with those funds . This leaves harm reduction agencies reliant on individual donations or small state or private grants to procure safer smoking material, if they are purchased at all. It is necessary for lawmakers, funders, and the broader community to recognize safer smoking practices and supplies as equally valuable and essential as safer injection practices and supplies given the small but growing evidence of the need for and health-related benefits of these services. Findings from this review underscore the necessity of ensuring that harm reduction services for people who smoke drugs, and the agencies that serve them, be given the same attention and financial support as services designed for people who inject drugs.
Limitations and strengths
This review has several limitations. All included studies were observational or retrospective and were thus subject to recall bias. Due to the social stigma surrounding substance use, study participants may have underreported some behaviors. Since the included studies had small sample sizes their findings may not be applicable to larger samples or different contexts, such as geographic regions, ethnicities, or genders.
Despite these limitations, this review also has strengths. All 32 studies included in this review are from peer-reviewed academic journals. To the authors’ knowledge, this is the first systematic review examining safer smoking in the harm reduction context and thus, provides synthesized information not previously available in the literature.
Overall, findings from this systematic review underscore the great need for harm reduction service providers to adapt their services to meet the needs of people who smoke drugs. Service adaptation will require changes in policy and practice to improve the availability and dissemination of safer smoking materials to people who smoke drugs. Consumption sites inclusive of safer smoking are valuable resources that need to be available to support harm reduction activities for people who smoke drugs. Additionally, ongoing high-quality research is needed to better understand how people smoke drugs and the feasibility, acceptability, and efficacy of safer smoking services in the U.S. and globally.
Availability of data and materials
Glass stem/pipe- glass tubes used most often to smoke crack or methamphetamine, Brass screens- a filter used to hold a crack rock in place in a stem/pipe, Rubber mouthpiece- barrier used at the end of pipe to protect against cuts, burns, and disease transmission and can be switched out when sharing stems/pipes, Chopstick/push stick- used to pack the filter into place and push filter around to collect residue, Lip balm-to protect against chapped lips due to smoking, Foil-small squares of aluminum foil used most often to smoke opiates, Plastic straws-Used for safer sniffing of drugs.
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The authors would like to give tremendous gratitude to Smokeworks, especially Jim Duffy, for enabling this research to be conducted. Additional thanks to Kate Silfen at Boston University for her assistance in refining the search strategy.
AT, CA, ZGL and NM’s contributions to this review were supported by Smokeworks Injection Alternatives.
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Author’s AT, CA, ZGL, and NN were paid researchers on behalf of Smokeworks Injection Alternatives. Smokeworks had no control over design and interpretation of results.
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Appendix: Search strategy
Appendix: Search strategy
Safer smoking practices
People who smoke drugs
A. Set 1–5 were merged with “AND”
B. Set 6–8 were merged with “NOT”
C. Set 1–8 were combined
D. De duplicated
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Tapper, A., Ahern, C., Graveline-Long, Z. et al. The utilization and delivery of safer smoking practices and services: a narrative synthesis of the literature. Harm Reduct J 20, 160 (2023). https://doi.org/10.1186/s12954-023-00875-x