Thirdhand smoke is the chemical residue left behind by secondhand smoke that can linger for years in dust and on household surfaces. It can also become embedded in carpets, furniture, fabrics, and building materials, turning them into reservoirs of pollutants. Also known as “tobacco smoke residue” or “stale tobacco smoke”, the mixture of pollutants in thirdhand smoke is toxic to humans, especially children.
Scientists have just started to study the smoke from cannabis. The studies show that cannabis smoke has some of the same cancer-causing chemicals as tobacco smoke. Cannabis smoke leaves behind thirdhand smoke residue that is like the residue from tobacco smoke.
Just like vaping nicotine creates thirdhand smoke, vaping cannabis creates thirdhand smoke too. The active ingredient in cannabis that produces the “high” accumulates on surfaces in rooms where cannabis has been vaped. Although exposure to cannabis-related thirdhand smoke residue will not get someone “high”, the cannabis residue can accumulate on surfaces, collect in dust, and soak into materials.
Do you have more questions about the toxic legacy of tobacco smoke, how it affects human health, and what we can do about it? Learn more here.
Updated: March 2023
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