Industry News

THC Can Accumulate on Surfaces After Vaporizer Use

Written by Caleb Summeril

Vaporizing cannabis has become a common method of consumption that has been growing steadily with an ever-increasing number of people adopting the technique. While the rise in popularity and use of vaporizers is evident, the research behind the effects of this type of use is yet to be fully explored. Many have heard of the potential ill effects of second/third-hand smoke in regards to tobacco. New studies are taking a look at the effects vaporized cannabis may have.

A recent study published in 2019 set out to examine the surface detection of delta-9-tetrahydrocannabinol (THC) from vaporizer use in a controlled indoor environment. The potential results from this study are intriguing for the implications they represent towards possible potential of third-hand cannabis exposure. When vaporized indoors, cannabis can potentially be deposited on surfaces and objects thereby leading to this third-hand exposure. [1]

The study was conducted in a sealed control room filled with common objects similar to a normal house or apartment including a table, reclining chair, and pegboard. A pharmacist prepared whole plant cannabis material of approximately 4.5-5.4% THC in a 400 mg sample to be vaporized in the 27.26 m3 control room and vaporized the material at 200° C. [1] Test subjects then used common inhale and exhale techniques with an 8 liter balloon off of a Volcano Vaporizer to fill the room with cannabis vapor.

After the room was filled with cannabis vapor, fresh air was circulated into the room and test samples were collected off of the objects in the room using isopropanol imbued non-woven wipes. Each of the surfaces were swabbed three times with different patterns. The samples were then analyzed using liquid chromatography-tandem mass spectrometry and online extraction.

Results showed a positive result for the presence of THC on 6 out of 15 samples in measurable levels from 348-4882 ng/m2. [1] These findings indicate that the presence of cannabis vapor in a room can indeed build up and deposit on surfaces and, therefore, may lead to possible third-hand exposure. While this study shows that THC can affect indoor environments where vapor is present, more research needs to be conducted to display how this deposited material may affect and/or interact with individuals exposed to the “contaminated” objects.


  1. Sempio, Cristina, et al. “Surface Detection of THC Attributable to Vaporizer Use in the Indoor Environment.” Scientific Reports, vol.9, no.1, 2019, pp.185-87. Journal Impact Factor = 4.122

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About the author

Caleb Summeril

Caleb Summeril writes creative copy, stories and songs from the mountains of Colorado. When not working on words, he can be found on global gallivants which fuel future endeavors. Learn more about his writing services at