Second Hand Cannabis Smoke

Fine Particulate Matter Exposure From Secondhand Cannabis Bong Smoking
Jama Network 2022, March 30

This cohort study suggests that, contrary to popular beliefs, bong smoking is not safe. Decades ago, many people thought SHTS presented no health risk to nonsmokers. Scientific research since then changed this perception and led to smoke-free environments.3 Incorrect beliefs about SHCS safety promote indoor cannabis smoking.1,2 Nonsmokers are exposed to even higher concentrations of SHCS materials during “hot-boxing,” the popular practice in which cannabis smokers produce high volumes of smoke in an enclosed environment. This study’s findings suggest SHCS in the home is not safe and that public perceptions of SHCS safety must be addressed…

Measuring indoor fine particle concentrations, emission rates, and decay rates from cannabis use in a residence
Science Direct 2021, April

This study shows that smoking a marijuana joint indoors can produce extremely high indoor PM2.5 concentrations. Based on the results of 24 experiments, smoking cannabis joints for 3.0 min in a 43 m3 room produced maximum PM2.5 concentrations averaging 540 μg/m3 that ranged from 143 to 809 μg/m3. By comparison, the Marlboro tobacco cigarettes smoked in the same manner in the same room produced maximum PM2.5 concentrations averaging 154 μg/m3 that ranged from 22 to 209 μg/m3


An emerging allergen: Cannabis sativa allergy in a climate of recent legalization
BMC 2020, June 26

The legalization and accessibility of Cannabis sativa in Canada has created a renewed interest in the health implications of its use, including allergic and immunologic consequences. This brief review has highlighted the diversity of sensitization routes and reactions to the plant, emphasizing the heterogenous presentation of Cannabis allergy. In addition, this article has underscored the fledgling nature of available testing and treatment options for C. sativa allergy. There have been recent, exciting advancements in isolation of culprit allergens and clinical testing, although these are not yet applicable to general office use. At the moment, there are existing practical suggestions for diagnosing and treating C. sativa allergy, which will hopefully evolve in the coming years as Can s 3 preparations and immunotherapy schedules mature and become commercially available. However, currently, a detailed allergy history with adjunct hemp sIgE testing are the cornerstones of diagnosis, and avoidance (in combination with standard symptomatic treatment) is the mainstay of treatment…

Cannabis allergy: what the clinician needs to know in 2019
Taylor & Francis 2019, February 1

Cannabis allergy is an allergy entity which can significantly impact the quality of life. For optimal diagnosis, we advise to start with a validated and standardized crude-extract based test such as sIgE hemp complemented by component-based diagnostics such as sIgE Can s 3 quantifications where available. Future research should lift the veil on the true prevalence of cannabis allergy and the importance of other cannabis allergens to further guide our practice…


Surface Detection of THC Attributable to Vaporizer Use in the Indoor Environment Scientific Reports 2019, December 09

We showed that in a room in which cannabis was administered by vaporization surfaces tested positive for THC at quantifiable levels. This study represents a first step in understanding how side-stream cannabis vapor deposits in the environment and may result in tertiary exposure to users and bystanders…

Marijuana and Tobacco Coexposure in Hospitalized Children
American Academy of Pediatrics 2018, December 1

Approximately half of the children who qualified for our study had biological evidence of exposure to marijuana. Researchers in studies such as this provide valuable data on secondhand exposure to children from parents using tobacco and marijuana and can inform public health policies to reduce harm…


Health effects of exposure to second- and third-hand marijuana smoke: a systematic review
National Center for Biotechnology Information 2017 November 24

Tetrahydrocannabinol metabolites are retained in the body upward of 4 hours, and people report the experience of psychoactive effects after exposure to second-hand smoke. On a molecular level, marijuana smoke has chemical components similar to those of tobacco smoke, although they are present in different amounts. Although this provides support for the biological plausibility of the relation between exposure to second-hand marijuana smoke and negative health outcomes, there is a gap in the literature in this area. If exposure to second-hand marijuana smoke has similar health risks as direct marijuana use, it may be associated with conditions such as respiratory and cardiac disease as well as mental illness. However, high-quality research on the long- and short-term health effects of exposure to second-hand marijuana smoke are required to confirm these possible risks. Given the current state of knowledge, coherent policy approaches to exposure to smoke of any kind may result in the most effective harm-reduction policy…

Detecting biomarkers of secondhand marijuana smoke in young children
Nature Publishing Group 2017, April

Conclusion: Metabolites of marijuana smoke can be detected in children; in this cohort, 16% were exposed.

Detectable COOH-THC is more common in children with tobacco smoke exposure. More research is needed to assess the health impacts of marijuana smoke exposure on children and inform public health policy…

One Minute of Marijuana Secondhand Smoke Exposure Substantially Impairs Vascular Endothelial Function
National Center for Biotechnology Information 2016, July 27

 One minute of exposure to marijuana SHS substantially impairs endothelial function in rats for at least 90 minutes, considerably longer than comparable impairment by tobacco SHS. Impairment of FMD does not require cannabinoids, nicotine, or rolling paper smoke. Our findings in rats suggest that SHS can exert similar adverse cardiovascular effects regardless of whether it is from tobacco or marijuana…