Effects of Marijuana On The Lungs and Respiratory System


Chest CT Findings in Marijuana Smokers

RSNA 2022, Nov 15

Airway inflammation and emphysema were more common in marijuana smokers than in nonsmokers and tobacco-only smokers, although variable interobserver agreement and concomitant cigarette smoking among the marijuana-smoking cohort limits our ability to draw strong conclusions.

E-cigarette or vaping product use-associated lung injury (EVALI)
Authors: Helen Hollingsworth, MD Hasmeena Kathuria, MD 2022, June 24

EVALI was initially recognized in the summer of 2019 [3,7-10]. More than 2800 hospitalized cases of EVALI were reported to the Centers for Disease Control and Prevention (CDC) as of February 18, 2020, and, among those, there have been 68 deaths [5]. The CDC stopped collecting these data in February 2020; epidemiologic statistics can be found at the CDC website. Approximately 66 percent of reported cases were male, and nearly 80 percent were younger than 35 years old (range 13 to 85 years) [6]. Approximately 22 percent of patients had underlying asthma [3].

Data obtained from emergency department visits associated with possible EVALI, Google searches, and case reports to the CDC confirmed similar trends in all three databases for potential cases of EVALI [11]. Peaks were seen between June and September of 2019, with a subsequent reduction in trends since then…

Cannabinoid exposure as a major driver of pediatric acute lymphoid Leukaemia rates across the USA
BMC Cancer 2021, July 7

Acute lymphoid leukaemia (ALL) is the commonest childhood cancer whose incidence is rising in many nations. In the USA, between 1975 and 2016, ALL rates (ALLRs) rose 93.51% from 1.91 to 3.70/100,000 <  20 years. ALL is more common in Caucasian-Americans than amongst minorities. The cause of both the rise and the ethnic differential is unclear, however, prenatal cannabis exposure was previously linked with elevated childhood leukaemia rates. We investigated epidemiologically if cannabis use impacted nationally on ALLRs, its ethnic effects, and if the relationship was causal…


Epidemiological overview of multidimensional chromosomal and genome toxicity of cannabis exposure in congenital anomalies and cancer development 
Scientific Reports 2021, July 6

Cancer data was downloaded for the fifty US states from 2001 to 2017 from the SEER registry. Congenital birth anomaly data was taken from NBDPN CDC annual reports. It was adjusted to include estimates of early termination of pregnancy for anomaly (ETOPFA) taken from the published literature. These datasets were matched with drug use data from NSDUH at SAMHSA for the period 2003–2017 so that the fifteen years 2003–2017 became the period of analysis. There were therefore 750 datapoints for analysis. This data was supplemented by income and ethnicity data from US census bureau and cannabinoid concentration data from DEA.

Cannabis use quintiles were calculated for each year. The mean percentage rates of cannabis use are shown in Supplementary Table…

Quadruple convergence – rising cannabis prevalence, intensity, concentration and use disorder treatment
The Lancet 2021, October 25

In collating and synthesizing several data sources on cannabis exposure, Manthey and colleagues have elegantly compiled a foundational resource for subsequent epidemiological studies on cannabis use. The study includes an impressive body of evidence on cannabis use prevalence (in the month and year prior to interview), high risk cannabis use (daily or near daily), tetrahydrocannabinol (THC—the principal psychoactive constituent of cannabis) concentration in European cannabis herb and processed resin (cannabis concentrates), and treatment demand for Cannabis Use Disorder (CUD). All four domains studied show a modest to dramatic increases across 2010-2019…



Cannabis Vaping: Existing and Emerging Modalities, Chemistry, and Pulmonary Toxicology ACS Publications 2021, October 8

The outbreak of e-cigarette or vaping product use-associated lung injury (EVALI) has been cause for concern to the medical community, particularly given that this novel illness has coincided with the COVID-19 pandemic, another cause of severe pulmonary illness. Though cannabis e-cigarettes tainted with vitamin E acetate were primarily associated with EVALI, acute lung injuries stemming from cannabis inhalation were reported in the literature prior to 2019, and it has been suggested that cannabis components or additives other than vitamin E acetate may be responsible. Despite these concerning issues, novel cannabis vaporizer ingredients continue to arise, such as Δ8-tetrahydrocannabinol, Δ10-tetrahydrocannabinol, hexahydrocannabinol, and cannabichromene. In order to address cannabis e-cigarette safety and vaping in an effective manner, we provide a comprehensive knowledge of the latest products, delivery modes, and ingredients. This perspective highlights the types of cannabis vaping modalities common to the United States cannabis market, with special attention to cartridge-type cannabis e-cigarette toxicology and their involvement in the EVALI outbreak, in particular, acute lung injurious responses…

Inhaled Marijuana and the Lungs
American Thoracic Society 2021, October 5

How can smoking marijuana damage
your lungs?

What symptoms may indicate that marijuana
is affecting your lungs?

What are the risks of vaping marijuana?

Is there a way to inhale marijuana safely?

Can smoking marijuana increase your risk for
lung infections?

Does smoking marijuana increase your risk of
getting lung cancer?

Hasn’t marijuana been used to treat people with
health problems?

Can smoking marijuana help you sleep?

What about people who are exposed to the
smoke from marijuana?


Lung Health and Marijuana Smoke
American Lung Association 2020, December 17

Smoking marijuana clearly damages the human lung. Research shows that smoking marijuana causes chronic bronchitis and marijuana smoke has been shown to injure the cell linings of the large airways, which could explain why smoking marijuana leads to symptoms such as chronic cough, phlegm production, wheeze and acute bronchitis.

Smoking marijuana has also been linked to cases of air pockets in between both lungs and between the lungs and the chest wall, as well as large air bubbles in the lungs among young to middle-aged adults, mostly heavy smokers of marijuana.

Smoking marijuana can harm more than just the lungs and respiratory system—it can also affect the immune system and the body’s ability to fight disease, especially for those whose immune systems are already weakened from immunosuppressive drugs or diseases, such as HIV infection…

Comprehensive characterization of mainstream marijuana and tobacco smoke
scientific reports 2020, April 28 

Recent increases in marijuana use and legalization without adequate knowledge of the risks necessitate the characterization of the billions of nanoparticles contained in each puff of smoke. Tobacco smoke offers a benchmark given that it has been extensively studied. Tobacco and marijuana smoke particles are quantitatively similar in volatility, shape, density and number concentration, albeit with differences in size, total mass and chemical composition. Particles from marijuana smoke are on average 29% larger in mobility diameter than particles from tobacco smoke and contain 3.4× more total mass. New measurements of semi-volatile fractions determine over 97% of the mass and volume of the particles from either smoke source are comprised of semi-volatile compounds. For tobacco and marijuana smoke, respectively, 4350 and 2575 different compounds are detected, of which, 670 and 536 (231 in common) are tentatively identified, and of these, 173 and 110 different compounds (69 in common) are known to cause negative health effects through carcinogenic, mutagenic, teratogenic, or other toxic mechanisms. This study demonstrates striking similarities between marijuana and tobacco smoke in terms of their physical and chemical properties…


Cannabis use and risk of lung cancer
European Respiratory Journal 2007, August 21

The aim of the present study was to determine the risk of lung cancer associated with cannabis smoking.

A case–control study of lung cancer in adults ≤55 yrs of age was conducted in eight district health boards in New Zealand. Cases were identified from the New Zealand Cancer Registry and hospital databases. Controls were randomly selected from the electoral roll, with frequency matching to cases in 5-yr age groups and district health boards. Interviewer-administered questionnaires were used to assess possible risk factors, including cannabis use. The relative risk of lung cancer associated with cannabis smoking was estimated by logistic regression.

In total, 79 cases of lung cancer and 324 controls were included in the study. The risk of lung cancer increased 8% (95% confidence interval (CI) 2–15) for each joint-yr of cannabis smoking, after adjustment for confounding variables including cigarette smoking, and 7% (95% CI 5–9) for each pack-yr of cigarette smoking, after adjustment for confounding variables including cannabis smoking. The highest tertile of cannabis use was associated with an increased risk of lung cancer (relative risk 5.7 (95% CI 1.5–21.6)), after adjustment for confounding variables including cigarette smoking.

In conclusion, the results of the present study indicate that long-term cannabis use increases the risk of lung cancer in young adults…