Smoke is smoke. When you burn something, it releases dangerous chemicals and marijuana is no different.  Secondhand marijuana smoke contains many of the same cancer-causing substances and toxic chemicals as secondhand tobacco smoke.  Some of the known carcinogens or toxins present in marijuana smoke include: acetaldehyde, ammonia, arsenic, benzene, cadmium, chromium, formaldehyde, hydrogen cyanide, lead, mercury, and nickel (1).

Marijuana can be consumed in a solid, liquid or semi-solid (wax) forms.  When burned, marijuana smoke can be emitted from many different types of devices and make-shift apparatuses such as bongs, pipes, rolled paper, cans, and e-cigarettes/”vapes”(2).

Knowing the dangers of marijuana smoke is an important first step to helping protect yourself and your children from the harmful effects.  As with any other secondhand smoke, the toxic substances and carcinogens can easily be inhaled by children even when they aren’t smoking.

Take ONE Step to Protect Loved Ones from Secondhand Marijuana Smoke Exposure

Knowing and understanding the dangers will help you create safe breathing environments as well as inform other parents of the risks, myths, and preventive measures regarding secondhand smoke and aerosols (3).

  • Smoke outside, away from windows, doors, and children
  • Don’t allow smoking at any time or place children will be present (home, car, etc.)
  • Teach children how to stay away from secondhand smoke
  • Model a tobacco and smokefree lifestyle
  • Implement a smokefree house/property policy
  • Be honest with young people about how difficult it is to quite smoking and encourage them not to start

If you’re ready to change your tobacco use, check out these support resources.

Secondhand Marijuana Smoke Facts

As with any other type of secondhand smoke, the toxic substances and carcinogens in marijuana secondhand smoke can easily be inhaled by children who are present or frequent the areas where smoking takes place.

  • It has many of the same chemicals as tobacco smoke, including those linked to lung cancer.
  • It impairs blood vessel function.  Furthermore, the exposure to secondhand marijuana smoke created longer-lasting effects on blood vessel function than exposure to secondhand tobacco smoke.
  • People who are exposed to secondhand marijuana smoke can have detectable levels of THC in their systems.
    • Recent studies have found strong associations between those who said there was someone in the home or a caretaker who used marijuana and the child having detectable levels of THC (the psychoactive ingredient in marijuana) (4).
  • Current scientific knowledge suggests that marijuana and tobacco secondhand smoke have similar makeup, and can have similar negative impacts on cardiovascular (heart and blood vessels) health, leading to partially blocked arteries, stroke, heart attack, and even death.
  1. American Nonsmokers’ Rights Foundation “Secondhand Marijuana Smoke.”  Retrieved from:
  2. American Lung Association “Marijuana and Lung Health.”  Retrieved from:
  3. Centers for Disease Control and Prevention “2006 Surgeon General’s Report Highlights – How to Protect Yourself and Your Loved Ones from Secondhand Smoke.”  Retrieved from:
  4. Centers for Disease Control and Prevention “Marijuana Health Effects.”  Retrieved from:

Page last updated: November 21, 2022

Freedom From Smoking Clinic
, | May 29, 2024
Freedom From Smoking Clinic
Detroit, MI | May 29, 2024