Secondhand Cannabis Smoke Exposure for Healthy Subjects

(CAN03 Trial)

Overseen By Abel Huang, BS

Age: 18 - 65

Sex: Any

Trial Phase: Academic

Sponsor: University of California, San Francisco

Must not be taking: Cannabis, CBD, THC, others

Disqualifiers: Asthma, Heart disease, Hypertension, Diabetes, others

No Placebo Group All trial participants will receive the active study treatment (no placebo)

Compensation: Varies

Number of Visits: 2

What You Need to Know Before You Apply

What is the purpose of this trial?

This trial examines how secondhand cannabis smoke affects healthy nonsmokers. Participants will visit public places where cannabis is used and remain there for up to four hours to observe any changes. It suits healthy adults who do not smoke and are not frequently exposed to smoke. The trial covers transportation costs and ensures staff accompany participants throughout. As an unphased study, this trial provides a unique opportunity to contribute to understanding the effects of cannabis smoke exposure in real-world settings.

Do I have to stop taking my current medications for the trial?

The trial does not specify if you need to stop taking your current medications, but it excludes those using cannabis products or more than two psychiatric medications.

What prior data suggests that this exposure to secondhand cannabis smoke is safe for healthy nonsmokers?

Research has shown that secondhand cannabis smoke can be risky. This smoke contains many of the same harmful chemicals as tobacco smoke, and sometimes even more. These chemicals can include toxins and potential carcinogens. Additionally, people who inhale secondhand cannabis smoke might absorb substances that can make them feel high, even without using cannabis themselves.

Some individuals exposed to this smoke have reported breathing problems. Interestingly, non-users exposed to the smoke sometimes experience fewer symptoms than regular cannabis users who aren't exposed. Awareness of these possible effects is important, even if they don't affect everyone. ^{1 2 3 4 5}

Why are researchers excited about this trial?

Researchers are excited about this trial because it aims to understand the effects of secondhand cannabis smoke exposure, a topic that has not been thoroughly studied yet. Unlike other studies that focus on direct cannabis use, this trial examines how being in public places where cannabis is consumed might impact people nearby. The study explores real-world scenarios by taking participants to locations where cannabis is smoked, vaporized, or dabbed, providing insights into potential health effects from secondhand exposure. This approach could lead to better public health guidelines and awareness, given the increasing legalization and use of cannabis products.

What evidence suggests that secondhand cannabis smoke exposure is effective for studying its impact on healthy nonsmokers?

Research has shown that exposure to cannabis smoke can introduce traces of cannabis chemicals into the body. People might also experience effects such as feeling high from this smoke. Secondhand cannabis smoke contains many of the same harmful chemicals as tobacco smoke, with some present in higher amounts. Cannabis smoke is released into the air more than tobacco smoke. This trial will expose participants to secondhand cannabis smoke in public places to study its effects. These findings suggest that inhaling secondhand cannabis smoke might pose health risks similar to those of tobacco smoke. ^{1 2 3 5 6}

Who Is on the Research Team?

Suzaynn F Schick

Principal Investigator

University of California, San Francisco

Are You a Good Fit for This Trial?

This trial is for healthy adult nonsmokers aged 21-50 with normal blood pressure and BMI, who don't use cannabis or tobacco products, aren't exposed to smoke in their jobs, and have no major health issues like heart disease or diabetes. Pregnant women and those with a history of drug abuse or certain psychiatric conditions cannot participate.

Inclusion Criteria

I am a nonsmoker, aged 21-50, with a BMI between 18.1 and 34.9.

I am a nonsmoker, aged 21-50, with a blood pressure below 150.

I am a healthy adult aged 21-50 and I do not smoke.

Exclusion Criteria

Regular exposure to secondhand tobacco or cannabis smoke

Current illicit drug use (by history or urine test)

Occupational exposure to smoke, dusts OR fumes

Timeline for a Trial Participant

Screening

Participants are screened for eligibility to participate in the trial

1-2 weeks

Exposure

Participants are exposed to secondhand cannabis smoke in public places for 0.5-4 hours

1 day

1 visit (in-person)

Post-exposure Monitoring

Participants' urinary cannabinoid metabolites are measured the morning after exposure

Up to 22 hours

1 visit (in-person)

Follow-up

Participants are monitored for any delayed effects or additional data collection

1-2 weeks

What Are the Treatments Tested in This Trial?

Interventions

• Secondhand cannabis emissions/smoke exposure

Trial Overview

The study investigates the effects of secondhand cannabis smoke on healthy individuals. Participants will be exposed to this environment without any blinding as part of a pilot study to measure pollutants and exposures from the smoke.

How Is the Trial Designed?

Group I: Exposure to secondhand cannabis smoke in public places Experimental Treatment 1 Intervention

The research staff and participants will travel together to a public location by either ride share vehicles, taxis or public transit. The study will arrange and pay for the transit. Staff and participants will be exposed to ambient air in public places where cannabis products are being consumed by smoking, vaporizing or dabbing. Participants will remain in the company of the laboratory staff throughout the exposure. The exposures will last 0.5-4 hours, depending on the nature and duration of the event. Staff and participants will travel together back to the laboratory for the post-exposure study measures.

Who Is Running the Clinical Trial?

University of California, San Francisco

Lead Sponsor

Trials

2,636

Recruited

19,080,000+

Citations

1.

pmc.ncbi.nlm.nih.gov

pmc.ncbi.nlm.nih.gov/articles/PMC5741419/

and third-hand marijuana smoke: a systematic review

Exposure to second-hand marijuana smoke leads to cannabinoid metabolites in bodily fluids, and people experience psychoactive effects after such exposure.

2.

no-smoke.org

no-smoke.org/secondhand-marijuana-smoke-fact-sheet/

Secondhand Marijuana Smoke Fact Sheet

Peer-reviewed and published studies indicate that exposure to secondhand marijuana smoke may have health and safety risks for the public, ...

3.

jamanetwork.com

jamanetwork.com/journals/jamanetworkopen/fullarticle/2829482

Exposure to Secondhand Cannabis Smoke Among Children

In this cross-sectional study, in-home cannabis smoking was associated with significantly increased odds of child exposure to cannabis smoke, as assessed by ...

4.

cdc.gov

cdc.gov/cannabis/health-effects/secondhand-smoke.html

Cannabis and Secondhand Smoke

Secondhand cannabis smoke contains many of the same toxic and cancer-causing chemicals found in tobacco smoke and some in higher amounts.

5.

sciencedirect.com

sciencedirect.com/science/article/abs/pii/S1352231020304635

Calibration factor, emission rate, and particle removal rate

Emission rates of secondhand cannabis smoke were 2–6 times of tobacco smoke. •. Fresh secondhand cannabis showed a bimodal size distribution. •.

6.

sciencedirect.com

sciencedirect.com/science/article/pii/S221133552400250X

Secondhand cannabis smoke exposure and respiratory ...

Lastly, past 30-day cannabis users who were not exposed reported more severe respiratory symptoms compared to non-users who were exposed (p < 0.001). In main ...