Most Cannabis Users Worldwide Smoke at Home, Exposing Others to Secondhand Smoke | Research

The takeaway

Among 64,000 cannabis users from the Global Drug Survey, about 64% reported smoking cannabis at home, with roughly one-quarter doing so daily, exposing household members to secondhand and thirdhand smoke.

Public health officials, housing authorities, and families of cannabis users

~64% of cannabis users smoke at home

What the researchers found

Among international cannabis users, any in-home smoking was reported by 63.9% of men, 61.9% of women, and 68.6% of nonbinary people. Daily in-home smoking was highest among nonbinary respondents (28.7%) and those 35+ years old (28.0%). US-specific weighted estimates showed any in-home smoking at 49.8% for males and 61.2% for females, with daily rates of 23.2% and 37.1% respectively.

Why it matters

In-home cannabis smoking exposes household members to secondhand and thirdhand smoke. With the number of cannabis users increasing due to legalization, and criminal stigma driving use indoors, residential exposure is a growing public health concern.

The numbers in context

International: 63,797 respondents. 63.9% of male, 61.9% of female, 68.6% of nonbinary users smoked at home. Daily in-home: 28.7% nonbinary, 28.0% age 35+. US weighted: any in-home 49.8% male/61.2% female. Daily: 23.2% male/37.1% female.

How the study worked

Cross-sectional analysis of 63,797 international cannabis users from the 2020 Global Drug Survey (Nov 2019-Jan 2020). US respondents (n=6,580) were weighted to the nationally representative NSDUH cannabis-using population using inverse odds probability weighting.

What this study cannot tell us

Global Drug Survey is a convenience sample that overrepresents engaged drug users. Self-reported in-home smoking may underestimate actual behavior. Weighting corrects for some selection bias in US data but cannot fully address it.

How to read the evidence

Large international sample with US-specific weighting, though convenience sampling limits representativeness.

When this study was published

2024 study using 2019-2020 data

The bigger picture

The paradox of legalization is that while it reduces the stigma of cannabis use, it may increase residential exposure because users feel more comfortable smoking at home. Criminal stigma has historically driven users indoors; legal stigma may be replaced by social norming of home use.

Questions still open

What are the actual health effects of residential secondhand cannabis smoke exposure? Would clean air laws that include cannabis change home smoking patterns? How does thirdhand cannabis smoke compare to tobacco in terms of persistence?

Common questions

How many cannabis users smoke at home?

About 64% of cannabis users internationally reported smoking at home, with about a quarter doing so daily. In the US, the rate was slightly lower among males (50%) but higher among females (61%).

Who is most likely to smoke cannabis at home daily?

In this international sample, nonbinary respondents (28.7%) and those over 35 (28.0%) had the highest daily in-home smoking rates. In the US, women had higher daily home smoking rates than men (37% vs 23%).

Read the original research

In-Home Cannabis Smoking Among a Cannabis-Using Convenience Sample from the Global Drug Survey: With Weighted Estimates for U.S. Respondents.

Cannabis and cannabinoid research, 9(1), 353-362

View on PubMed ↗Publisher’s paper ↗

Citation

Tripathi, Osika; Posis, Alexander Ivan B; Thompson, Caroline A; Ferris, Jason; Anuskiewicz, Blake; Nguyen, Benjamin; Liles, Sandy; Berardi, Vincent; Zhu, Shu-Hong; Winstock, Adam; Bellettiere, John. (2024). In-Home Cannabis Smoking Among a Cannabis-Using Convenience Sample from the Global Drug Survey: With Weighted Estimates for U.S. Respondents.. Cannabis and cannabinoid research, 9(1), 353-362. https://doi.org/10.1089/can.2022.0139