Cannabis use is associated with sexually dimorphic changes in executive control of visuospatial decision-making

Cannabis use has increased in parallel with college-aged individuals as recreational cannabis legalization increases. Temporal discounting studies with licit and illicit substances have shown that substance use frequency is positively associated with steeper discount rates. However, temporal discounting studies targeting cannabis use have shown either a small or no positive association between substance use frequency and discount rates. A previous social discounting study reported that current cannabis use participants showed significantly steeper discount rates relative to participants who self-reported no cannabis use. The present study extends those findings by focusing on current cannabis use participants to determine whether cannabis use frequency is correlated with decreased cannabis sharing. In addition, given the purported social nature of cannabis use, the present study examined associations between cannabis use frequency and self-report social use patterns. Eighty-nine college students self-reported current cannabis use rates via a cannabis engagement questionnaire and completed a social discounting task for cannabis. Results showed that cannabis use participants above the median (>4 cannabis use days in the past 30 days) shared significantly less hypothetical cannabis, relative to participants below the median (≤4 use days in the past 30 days). In addition, participants above the median were significantly less likely to self-report using cannabis "always or almost always with other people." These results extend previous findings that social discount rates are significantly associated with increased cannabis use within a social context. Implications for quantitative models assessing cannabis value and potential clinical diagnosis are discussed. (PsycInfo Database Record (c) 2026 APA, all rights reserved).

Efficacy and safety of a fatty acid amide hydrolase inhibitor (PF-04457845) in the treatment of cannabis withdrawal and dependence in men: a double-blind, placebo-controlled, parallel group, phase 2a single-site randomised controlled trial

BackgroundCannabis is the most commonly used illicit drug. In the general population, its use has been linked to a heightened propensity for suicidal behavior (SB). We hypothesize that this association varies in patients with psychiatric disorders. SB is known to vary by sex and therefore an investigation of cannabis’ association with SB must consider sex differences. The purpose of this study is to investigate the association between cannabis use and suicide attempts in men and women with psychiatric disorders.MethodsWe merged data collected for two studies based in Ontario, Canada (n = 985). We employed a multivariable logistic regression to assess the association between cannabis use and suicide attempts in men and women with psychiatric disorders.ResultsWe analyzed data from 465 men and 444 women. Amongst these, 112 men and 158 women had attempted suicide. The average age of our participants was 40 years (standard deviation (SD) 12.4). We found no significant association between suicide attempts and cannabis use in men (odds ratio (OR) = 1.34, 95% confidence interval (CI) 0.81, 2.22, p = 0.260) or women (OR = 0.97, 95% CI 0.61, 1.54, p = 0.884). In a sensitivity analysis using a sample of patients with substance use disorder only, the heaviness of cannabis use was associated with small but significant association with SB in men (OR = 1.03, 95% CI 1.01, 1.05, p = 0.007).ConclusionOur findings indicate that there is no association between cannabis use and suicidal behavior in men or women with psychiatric disorders unlike what was reported for the general population, though the heaviness of cannabis use may have an effect in men. The impact of cannabis use in psychiatric disorders needs ongoing examination in light of its common use, impending legalization with expected increased access and the uncertainty about cannabis’ effects on prognosis of psychiatric disorders. In addition, research should continue to investigate modifiable risk factors of SB in this population of which cannabis is not a significant factor based on this study.

BackgroundWe examined prospective associations between atypical working hours, substance use and sugar and fat consumption.MethodsIn the French population-based CONSTANCES cohort, 47,288 men and 53,324 women currently employed included between 2012 and 2017 were annually followed for tobacco and cannabis use; among them, 35,647 men and 39,767 women included between 2012 and 2016 were also followed for alcohol and sugar and fat consumption. Three indicators of atypical working hours were self-reported at baseline: working at night, weekend work and non-fixed working hours. Generalized linear models computed odds of substance use and sugar and fat consumption at follow-up according to atypical working hours at baseline while adjusting for sociodemographic factors, depression and baseline substance use if appropriate.ResultsWorking at night was associated with increased tobacco use in women [odds ratios ranging from 1.45 to 1.48], with increased cannabis use in men [from 1.40 to 1.54] and with increased alcohol use in both men and women [from 1.12 to 1.14]. Weekend work and non-fixed working hours were associated with increased tobacco and alcohol use in both men and women [from 1.15 to 1.54 and 1.12 to 1.14, respectively]. Dose-dependent relationships were found regarding the association between working at night and tobacco use in women as well as regarding non-fixed working hours and tobacco use in both men and women (P for trends <0.001).ConclusionsThe potential role of atypical working hours on substance use should be considered by public health policy makers and clinicians in information and prevention strategies.Key messages• Night shifts were associated with increased smoking in women with dose-dependent relationships, cannabis use in men and alcohol use in both.• Weekend work and non-fixed working hours were associated with increased alcohol and tobacco use with dose-dependent relationships in men and women.

As the overall prevalence of prenatal cannabis use rises, it is vital to also monitor trends in the frequency of cannabis use in the period leading up to and during pregnancy because more frequent use may confer greater health risks for mothers and their children. To examine trends in the frequency of self-reported cannabis use among pregnant women in the year before and during pregnancy. Cross-sectional study using data from 367 403 pregnancies among 276 991 women 11 years or older who completed a self-administered questionnaire on cannabis use during standard prenatal care in Kaiser Permanente Northern California from January 1, 2009, to December 31, 2017. The annual prevalence of self-reported daily, weekly, and monthly cannabis use among women before and during pregnancy was estimated using Poisson regression with a log link function, adjusting for sociodemographics. Data analyses were conducted from February to May 2019. Calendar year. Self-reported frequency of cannabis use in the year before pregnancy and during pregnancy assessed as part of standard prenatal care (at approximately 8 weeks' gestation). Among the overall sample of 367 403 pregnancies among 276 991 women, 35.9% of the women self-reported white race/ethnicity; 28.0%, Hispanic; 16.6%, Asian; 6.0%, African American; and 13.5%, other. In the sample, 1.2% of the women were aged 11 to 17 years; 15.3%, 18 to 24 years; 61.4%, 25 to 34 years; and 22.0%, older than 34 years. Median (interquartile range) neighborhood household income was $70 472 ($51 583-$92 643). From 2009 to 2017, the adjusted prevalence of cannabis use in the year before pregnancy increased from 6.80% (95% CI, 6.42%-7.18%) to 12.50% (95% CI, 12.01%-12.99%), and the adjusted prevalence of cannabis use during pregnancy increased from 1.95% (95% CI, 1.78%-2.13%) to 3.38% (95% CI, 3.15%-3.60%). Annual relative rates of change in self-reported daily cannabis use (1.115; 95% CI, 1.103-1.128), weekly cannabis use (1.083; 95% CI, 1.071-1.095), and monthly or less cannabis use (1.050; 95% CI, 1.043-1.057) in the year before pregnancy increased significantly, with daily use increasing most rapidly (from 1.17% to 3.05%). Similarly, annual relative rates of change in self-reported daily cannabis use (1.110; 95% CI, 1.089-1.132), weekly cannabis use (1.075; 95% CI, 1.059-1.092) and monthly or less cannabis use (1.044; 95% CI, 1.032-1.057) during pregnancy increased significantly from 2009 to 2017, with daily use increasing most rapidly (from 0.28% to 0.69%). Results of this study demonstrate that frequency of cannabis use in the year before pregnancy and during pregnancy has increased in recent years among pregnant women in Northern California, potentially associated with increasing acceptance of cannabis use and decreasing perceptions of cannabis-associated harms.

BackgroundThis study examined prospective associations between atypical working hours with subsequent tobacco, cannabis and alcohol use as well as sugar and fat consumption.MethodsIn the French population-based CONSTANCES cohort, 47,288 men and 53,324 women currently employed included between 2012 and 2017 were annually followed for tobacco and cannabis use. Among them, 35,647 men and 39,767 women included between 2012 and 2016 were also followed for alcohol and sugar and fat consumption. Three indicators of atypical working hours were self-reported at baseline: working at night, weekend work and non-fixed working hours. Generalized linear models computed odds of substance use and sugar and fat consumption at follow-up according to atypical working hours at baseline while adjusting for sociodemographic factors, depression and baseline substance use when appropriate.ResultsWorking at night was associated with decreased smoking cessation and increased relapse in women [odds ratios (ORs) of 0.81 and 1.25], increased cannabis use in men [ORs from 1.46 to 1.54] and increased alcohol use [ORs from 1.12 to 1.14] in both men and women. Weekend work was associated with decreased smoking cessation in women [ORs from 0.89 to 0.90] and increased alcohol use in both men and women [ORs from 1.09 to 1.14]. Non-fixed hours were associated with decreased smoking cessation in women and increased relapse in men [ORs of 0.89 and 1.13] and increased alcohol use in both men and women [ORs from 1.12 to 1.19]. Overall, atypical working hours were associated with decreased sugar and fat consumption.ConclusionsThe potential role of atypical working hours on substance use should be considered by public health policy makers and clinicians in information and prevention strategies.

Most clinical and epidemiologic estimates of prenatal cannabis use are based on self-report, and the validity of self-reported cannabis use has not been examined in a large, representative population of pregnant women. We determined the validity of self-reported prenatal cannabis use and predictors of nondisclosure using data from Kaiser Permanente Northern California's (KPNC) healthcare system with universal prenatal cannabis screening during prenatal care. Validation study using data from 281,025 pregnancies in KPNC among females aged ≥11 years who completed a self-administered questionnaire on prenatal cannabis use and a cannabis urine toxicology test from 2009 to 2017. We calculated sensitivity, specificity, positive predictive value, and negative predictive value of self-reported prenatal cannabis use using urine toxicology testing as the criterion standard, and sensitivity of urine toxicology testing using self-reported use as the criterion standard. We compared sociodemographics of those who disclosed versus did not disclose prenatal cannabis use. Urine toxicology testing identified more instances of prenatal cannabis use than self-report (4.9% vs 2.5%). Sensitivity of self-reported use was low (33.9%). Sensitivity of the toxicology test was higher (65.8%), with greater detection of self-reported daily (83.9%) and weekly (77.4%) than monthly or less use (54.1%). Older women, those of Hispanic race/ethnicity, and those with lower median neighborhood incomes were most likely to be misclassified as not using cannabis by self-reported screening. Given that many women choose not to disclose prenatal cannabis use, clinicians should educate all prenatal patients about the potential risks and advise them to quit cannabis use during pregnancy.

Background: Cannabis is the most frequently used recreational drug among pregnant women in the United States, with usage rates increasing due to legalization and decriminalization. Self-reported cannabis use during pregnancy varies from 2-28%, particularly among young, urban, socioeconomically disadvantaged women. These self-reported rates are suspected to be underestimated due to fear of retaliation and discrimination. Pregnant patients often perceive marijuana use as relatively safe, leading to its continued use throughout pregnancy and postpartum. Alternatives to cannabis commonly include tobacco smoking and vaping. While the use of traditional tobacco products during pregnancy has declined overall, the use of alternative tobacco products, such as vaping, has risen. The perinatal effects of cannabis alone and in combination with tobacco products have not been well-studied. Animal studies have shown that tetrahydrocannabinol (THC) crosses the placenta, potentially affecting the fetus. Evidence suggests that cannabis use may disrupt neurodevelopment, with some human studies indicating increased risks of stillbirth, low birth weight, and preterm birth. This study aims to assess whether cannabis use is associated with increased risks of preterm birth, cesarean delivery, low birth weight, and hypertensive disorders of pregnancy, and to compare these outcomes with those in patients using both cannabis and tobacco products, as well as those using cannabis with other recreational products. Methods: A retrospective cohort study was conducted on subjects (n=416) with documented cannabis and tobacco use during pregnancy, who delivered between July 2020 and August 2023 at a large university-based medical center in Louisiana. Whereas 416 charts were reviewed, 325 patients met the inclusion criteria, which included positive urine drug screens, English-speaking patients, intrauterine pregnancy, and delivery during the same admission as when collecting the drug screen, where urine drug screen results were available. Chart reviews included confirmation of self-reported cannabis, tobacco, and other recreational drug use with urine drug screen findings. Statistical analyses were performed using Chi-Square and Fisher’s Exact tests. The study was approved by the Institutional Review Board (IRB: STUDY00002464). Results: The average patient age was 21.58 years (SD 11.44), with an average Gestational Age of 29w+6d (SD 15 d). There group analyzed included 188 (58%) White, 131 (40%) Black, 6 (2%) of other races with 5 (2%) being of Hispanic ethnicity. Upon presentation for delivery, 128 (39%) were nulliparous, whereas 197 (61%) were multigravida, with 242 (74%) being singleton pregnancies and 83 (26%) being multifetal. Fetal Growth restriction was noted in 44 (13.5%) of patients, Hypertensive disorders in 80 (45%) patients, and diabetes in 18 (6%) of patients. The analysis revealed no statistically significant differences in the rates of preterm birth among the three groups (p = 0.603; Chi-Square Test). Additionally, the mode of delivery showed no significant differences between cannabis-only patients and those who used other recreational drugs (p = 0.60; Chi-Square Test). The rate of small for gestational age neonates did not differ between the cannabis-only group and the other recreational drug use group (p = 0.387; Fisher’s Exact Test). Placental size comparisons also showed no significant differences (p = 0.138; Chi-Square Test). Lastly, the development of hypertensive disorders of pregnancy was not significantly different between the groups (p = 0.283; Chi-Square Test). Limitations of the study include the small sample size, single recruitment site, and potential confounding factors such as advanced maternal age, pre-existing health conditions, and obesity. Conclusions: Prenatal cannabis exposure was not associated with increased rates of preterm birth, small for gestational age neonates, primary cesarean delivery, or hypertensive disorders of pregnancy. Furthermore, there were no significant differences in these perinatal outcomes between patients who used only cannabis, those who used cannabis and tobacco, and those who used cannabis with other recreational drugs. These findings contribute to the understanding of perinatal outcomes associated with prenatal cannabis exposure, highlighting the need for larger studies to confirm these results and explore the long-term effects on child development. Health professionals should continue to monitor and counsel pregnant patients on the potential risks associated with cannabis use.

Brief report: Are changes in cannabis use frequency associated with changes in alcohol use and smoking among people with HIV (PWH) - A substitution question.

This study aimed to examine trends in cannabis-positive urine drug screens (UDSs) among emergency department (ED) patients from 2008 to 2019 using data from the Veterans Health Administration (VHA) health care system, and whether these trends differed by age group (18-34, 35-64, and 65-75 years), sex, and race, and ethnicity. VHA electronic health records from 2008 to 2019 were used to identify the percentage of unique VHA patients seen each year at an ED, received a UDS, and screened positive for cannabis. Trends in cannabis-positive UDS were examined by age, race and ethnicity, and sex within age groups. Of the VHA ED patients with a UDS, the annual prevalence positive for cannabis increased from 16.42% in 2008 to 27.2% in 2019. The largest increases in cannabis-positive UDS were observed in the younger age groups. Male and female ED patients tested positive for cannabis at similar levels. Although the prevalence of cannabis-positive UDS was consistently highest among non-Hispanic Black patients, cannabis-positive UDS increased in all race and ethnicity groups. The increasing prevalence of cannabis-positive UDS supports the validity of previously observed population-level increases in cannabis use and cannabis use disorder from survey and administrative records. Time trends via UDS results provide additional support that previously documented increases in self-reported cannabis use and disorder from surveys and claims data are not spuriously due to changes in patient willingness to report use as it becomes more legalized, or due to greater clinical attention over time.

It is unknown how patterns of cannabis and other drug use changed among young adult cannabis users as they became, exited or stayed medical cannabis patients (MCPs) after California legalized cannabis for adult use in 2016. A cohort of 18–26 year-old cannabis users was recruited in Los Angeles in 2014–15 (64.8% male; 44.1% Hispanic/Latinx). Based on wave 1 (pre-legalization) and wave 4 (post-legalization) MCP status, four transition groups emerged: MCP, Into MCP, Out of MCP and NPU (non-patient user). Relationships between self-reported medical cannabis use, transition group membership, and cannabis/other drug use outcomes were examined. Changes in cannabis practices were consistent with changes in MCP status. Cannabis days, concentrate use, self-reported medical cannabis use and driving under influence of cannabis were highest among MCP, increased for Into MCP, and decreased for Out of MCP in wave 4. A majority of drug use outcomes decreased significantly by wave 4. Self-reported medical cannabis use was associated with more frequent cannabis use but less problematic cannabis and other drug use. Future studies should continue to monitor the impact of policies that legalize cannabis for medical or recreational use, and medical motivations for cannabis use on young adults’ cannabis and other drug use.

ABSTRACTBackground: Due to significant comorbidity and impairment associated with cannabis use and cannabis use disorder, understanding time trends in cannabis use and cannabis use disorder is an important public health priority.Objectives: To identify trends in cannabis use and cannabis use disorder overall, and by sociodemographic subgroup.Methods: Narrative review of published findings on trends in cannabis use and cannabis use disorders in data from repeated cross-sectional US general population surveys. In addition, in National Epidemiologic Survey on Alcohol and Related Conditions (NESARC; 2002–2002) and NESARC-III (2012–2013) data, logistic regression was used to examine whether trends differed between subgroups of adults.Results: The review showed that in adults, cannabis use increased over the past decade overall and within sociodemographic subgroups (gender, age, race/ethnicity, income, education, marital status, urbanicity, region, pregnancy status, disability status), with greater increases in men and disabled adults. Most sources also indicated significant increases in cannabis use disorders. New analysis showed significantly greater increases in adult cannabis use and cannabis use disorder in men (p ≤ .0001); young adults (p < .05); Blacks (vs. Whites, p < .01); low income groups (p < .001); never-married p ≤ .0001), and urban residents (p < .05). In adolescents, cannabis use generally decreased, although recent increases were observed in older and non-White adolescents.Conclusion: Cannabis use and cannabis use disorder are increasing in adults, with specific sociodemographic groups at higher risk, and may be increasing in some adolescent subgroups. Studies should determine mechanisms for differential trends to provide information to policymakers and enable informed decisions on cannabis legalization and service planning.

Currently, there is no data-driven cannabis reduction metric using biochemical verification, which represents a significant gap in cannabis harm reduction research, treatment and policy. Using aggregated data from 7 cannabis use disorder treatment trials, the aims of this analysis were to 1) determine if decreases in self-reported cannabis use correlate with a decrease in urinary cannabinoids and 2) determine the cut-off in reduction of creatinine-normalized cannabinoids (CN:THC) associated with self-reported cannabis use reduction. Exploratory aggregated analysis of 7 cannabis use disorder treatment trials. Individual studies were conducted in academic medical centers and community substance use treatment settings in the United States and led by investigators at the Medical University of South Carolina. Participants were included who had cannabis use data available through week 6 of study treatment and did not meet criteria for continuous cannabis abstinence (n = 471/920; 51%; analytic sample was 31% female; 67% White; 11% Hispanic; mean age of 25). Weekly self-reported cannabis use (days of use, sessions or grams of use per day, collected via daily diaries or timeline follow-back) and urinary cannabinoids [tetrahydrocannabinol (THC) metabolites; ng/ml]. The sample was categorized as 1) reduced self-reported cannabis use (50% reduction in frequency and/or 75% in amount; n = 220) or 2) no self-reported cannabis reduction (n = 251). Longitudinal models included indicators for reduction group, parent study, study week, baseline urinary cannabinoids and covariates (age, race, years of cannabis use) statistically significantly associated with study outcomes. Participants self-reporting cannabis use reduction had statistically significantly lower urinary cannabinoids compared with those who did not reduce [Δ between groups = 391 ng/ml; 95% confidence interval (CI) = 231-551; P < 0.001]. Average urinary cannabinoids decreased by up to 50% from baseline levels for the cannabis reduction group. The classification model for decrease in urinary CN:THC did not produce a cut-point statistically significantly different from zero (-39.9; 95% CI = -70.3 to 2.9). Average urinary cannabinoids, measuring THC, during cannabis use disorder treatment trials appear to differ between participants with and without self-reported cannabis use reduction. Urinary cannabinoids appear to decrease concurrently with self-reported use reduction, with a 50% average decrease being observed among those self-reporting reductions. Overall classification models did not yield a urinary creatinine-normalized cannabinoids cut-off that could be used for individuals to detect meaningful cannabis reduction. Individual-based biochemical verification of cannabis reduction will require further work to establish, though average reductions of at least 50% in urinary cannabinoids may be a useful metric for the majority of those with cannabis use disorder in clinical and research settings.

We appreciate the opportunity to respond to the comments from Mundt, Contreras & Ibanez [1] regarding our paper on cannabis legalization among school students in Uruguay [2]. In their letter, they raise several concerns regarding the use of Chilean secondary school students’ data as a comparison group. We believe that their concerns are, in fact, the main argument in favor of using Chile as comparator. First, the authors mention that Chile had the highest past-year prevalence of cannabis use in secondary school students in the Americas, which is true [3]. Uruguay is the country with the second highest prevalence of cannabis use among secondary students in South America [3]. In addition, the difference between both countries in the years prior to legalization was negligible (see Figure 1). Source: Rivera-Aguirre A et al. [2] Secondly, the authors mention that the large increase in past-year cannabis use from 2009 to 2015 in Chile could affect the comparison and, ultimately, the validity of our results [4]. Uruguay, however, also experienced an increase in past-year cannabis use in this same period, which peaked in 2016 [5]. Further, the key threat to the validity of a difference-in-difference analysis such as ours would be non-parallel pre-legalization trends in the two countries. Instead, past-year and past-month cannabis use followed similar pre-legalization trends in the two countries [2]. Thirdly, Mundt et al. also argue that Chile's 2005 cannabis decriminalization is another reason why Chile is not a good comparison group for Uruguay. We argue that this, in fact, makes Chile a better comparison group, because in Uruguay, cannabis use was already decriminalized [6]. In other words, decriminalization in Chile would resemble more closely what would have happened in Uruguay in the absence of legalization. Finally, in our effort to produce reliable estimates of the legalization policy in Uruguay, we recognize that we worked with imperfect counterfactuals and with limited opportunities to isolate the mechanisms that may or may not affect population levels of cannabis use. We agree with Mundt, Contreras & Ibanez [1] that increases in use (in Chile and in Uruguay) may be the result of changes in perceptions and social norms towards cannabis, probably influenced by decades of debate and more recent changes in policy in the Americas and beyond. In fact, we noted this in the Discussion section of our paper, as one of our findings was a transitory increase in cannabis use in Uruguay in 2014, prior to plausible changes in cannabis availability through legal sources. In conclusion, the information currently available supports our conclusions that allowing and implementing legal access to cannabis in a highly regulated market, as is the case of Uruguay [7], did not produce short-term changes in use among adolescents. This work was supported by the National Institute on Drug Abuse, R01DA040924-01 (Cerdá). ARA, AC and RQ received funding from ANID-Millennium Science Initiative Program, NCS2021003. None. Ariadne Rivera-Aguirre: Conceptualization; investigation. Alvaro Castillo-Carniglia: Conceptualization; investigation. Hannah S. Laqueur: Conceptualization; investigation. Kara E. Rudolph: Conceptualization; investigation. Silvia S. Martins: Conceptualization; investigation. Jessica Ramírez: Conceptualization; investigation. Rosario Queirolo: Conceptualization; investigation. Magdalena Cerdá: Conceptualization; funding acquisition; investigation.

Cannabis and tobacco couse is common and could expose users to higher levels of toxicants. No studies have examined biomarkers of toxicant exposure in cousers of cannabis and cigarettes, compared with cigarette smokers (CS). Adult daily CS were recruited from 10 US sites for a study of reduced nicotine cigarettes. In this analysis of baseline data, participants were categorized as either cousers of cannabis and tobacco (cousers; N = 167; urine positive for 11-nor-9-carboxy-Δ 9-tetrahydrocannnabinol and self-reported cannabis use ≥1×/week), or CS (N = 911; negative urine and no self-reported cannabis use). Participants who did not meet either definition (N = 172) were excluded. Self-reported tobacco and cannabis use and tobacco and/or combustion-related biomarkers of exposure were compared between groups. Compared to CS, cousers were younger (couser Mage = 38.96, SD = 13.01; CS Mage = 47.22, SD = 12.72; p < .001) and more likely to be male (cousers = 67.7%, CS = 51.9%, p < .001). There were no group differences in self-reported cigarettes/day, total nicotine equivalents, or breath carbon monoxide, but cousers had greater use of non-cigarette tobacco products. Compared to CS, cousers had higher concentrations of 3-hydroxypropylmercapturic acid, 2-cyanoethylmercapturic acid, S-phenylmercapturic acid, 3-hydroxy-1-methylpropylmercapturic acid (ps < .05), and phenanthrene tetraol (p < .001). No biomarkers were affected by number of cannabis use days/week or days since last cannabis use during baseline (ps > .05). Cousers had higher concentrations of biomarkers of exposure than CS, but similar number of cigarettes per day and nicotine exposure. Additional studies are needed to determine whether cannabis and/or alternative tobacco products are driving the increased toxicant exposure. Cousers of cannabis and tobacco appear to be exposed to greater levels of harmful chemicals (ie, volatile organic compounds and polycyclic aromatic hydrocarbons), but similar levels of nicotine as CS. It is unclear if the higher levels of toxicant exposure in cousers are due to cannabis use or the increased use of alternative tobacco products compared with CS. It is important for studies examining biomarkers of exposure among CS to account for cannabis use as it may have a significant impact on outcomes. Additionally, further research is needed examining exposure to harmful chemicals among cannabis users.