With two additional states (New Mexico and New York) decriminalizing and legalizing recreational marijuana/cannabis use and sales, it is even more important to advocate for worker and public health so that we do not see secondhand marijuana smoke make its way into indoor spaces. Smoke is smoke. We applaud decriminalizing marijuana, but it is worth repeating that marijuana smoke, just like other forms of smoking (like cigars and hookah) or vaping tobacco or marijuana, is not safe compared to breathing clean air.

New Research

A new study on particulate levels from marijuana smoke show a high rate of emissions – even higher than tobacco smoke. Researchers conducted 60 experiments comparing indoor particulate matter 2.5 (PM2.5) levels from secondhand marijuana smoke and secondhand tobacco smoke. PM2.5 is fine particulate matter that can be breathed deeply into lung tissue and is hazardous to health regardless of the source. Exposure to PM2.5 can cause lung irritation, asthma attacks, and makes respiratory infections more likely. Exposure to fine particulate matter can exacerbate health problems, especially for people with respiratory conditions like asthma, bronchitis, or COPD.

The study concluded that “the average PM2.5 emission rate of the pre-rolled marijuana joints was found to be 3.5 times the average emission rate of Marlboro tobacco cigarettes, the most popular US cigarette brand.” All cannabis sources included in the study had PM2.5 emission rates that were higher than the tobacco sources. This study illustrates that smoking a marijuana joint indoors can produce extremely high indoor PM2.5 concentrations, thereby exposing the public and workers to dangerous secondhand marijuana smoke emissions.

More research is needed, but this new research adds to the current body of science that shows that both tobacco and marijuana smoke have similar chemical composition and suggests that both types of secondhand smoke may have harmful cardiovascular health effects, such as atherosclerosis (partially blocked arteries), heart attack, and stroke.

Exposure to Secondhand Marijuana Is a Social Justice Issue

No one wants to see a new class of workers (those in marijuana retailers and hospitality spaces) who have to give up their health for a paycheck. Even if a person uses marijuana, it will be detrimental to their health to be exposed to these high levels of particulate matter for 8 hours at a time on a daily basis. Everyone deserves to breathe smokefree air indoors at work; as advocates for nonsmokers’ rights it’s our duty to ensure those rights aren’t infringed upon.

Big Tobacco Is also Big Marijuana

The tobacco industry has always cast doubt on the science of secondhand smoke. With money as motive, tobacco giant Altria (parent company of Philip Morris) is investing in the emergent marijuana industry and is stepping up its state and federal marijuana lobbying efforts to become the cannabis product market leader. Part of this role will be to seek indoor marijuana smoking. Recall that Altria is the same company that targeted the hospitality industry for years with economic and ventilation misinformation via the Philip Morris Accommodation and Options programs designed to prevent bars, casinos, and other hospitality businesses from implementing smokefree policies.

Read more: current marijuana facts

Read more about ventilation misinformation

Read more about Philip Morris attempts to sway public opinion and see documents about the Accommodation/Options program