How toxic is a vape pen and how do lab tests find out

Vape injuries occurred in 2019 because of THC adulterated with tocopherols (a vitamin derivative.) To prevent some issues before market, a lab can test cannabis oil for certain contaminants to determine how toxic a vape pen is. But how does a lab quantify a stream of aerosolized vapor or smoke?

how toxic is a vape pen?

Vapor containment in the lab

As a Health Canada-approved research laboratory nestled into the UBC campus grounds, Delic Labs is licensed to study cannabis and also psilocybin. They offer unique tests such as a smoke and vapor analysis, which, as Delic Labs described in a previous report, is capable of guiding the design and the experience of vaping.

The end-product must be tested for a proper result, and according to Dr. Markus Roggen, the President and CSO of Delic Labs, the end-product for a vape pen is the vapor. To do this, lab tests can ensure that a vape pen will deliver a good dose and a consistent flavor as well as determine if it is toxic.

A machine simply puffs on a vape pen or a lit joint, and the data is quantified — right?

If you Ask An Expert, many challenges hide behind the scenes that have led to many advances for this new type of lab test. Currently, there are three main courses of testing available for smoke and vapor with more on the way.

Test how toxic is a vape pen by measuring cannabinoids and terpenes

The simplest vapor test can measure cannabinoids and terpenes according to Sajni Shah, the laboratory manager at Delic Labs. Resins are trapped as vapor is mechanically puffed through a special filter, known as the filter pad. This can tell you how much THC is inhaled per puff. And the terpene levels, too.

Extracting those filter pads allows us to do relatively good qualitative [and quantitative] work on cannabinoids and terpenes.

Sajni Shah, Laboratory Manager, Delic Labs.

Things are still straightforward for this more simple test — a tool used for maintaining consistency and tuning the dose of every puff, for example. Vape pen safety is more complex than cannabinoid doses, though. Cannabis oils, especially terpenes, produce a potential slurry of toxins when exposed to excessive heat — a key catalyst to molecular change.

So we want to test for those toxicants and that’s where it gets more complicated. 

An impinger at Delic Labs is used to collect toxins from vape pen emissions.
Delic Labs uses an impinger (pictured) to collect toxins from vape pen emissions during their lab tests. Photo by Delic Labs.

Determine amount of Volatile Organic Compounds in Vape Pens

To trap lighter compounds, Delic Labs uses an impinger. Imagine a small, laboratory-style bong that vapor or smoke can be pulled through. Except that Delic Labs percolates their smoke and vapor through methanol — a poisonous solvent — to collect volatile organic compounds (VOCs) for later analysis. VOCs include isoprene, benzene, toluene, and other light toxins, for example.

We run a lot of smoke through really cold methanol, so we use dry ice to help catch the VOCs. 


A special test known as Gas Chromatography-Mass Spectrometry (GC-MS) is then employed to quantify the residual toxins once those volatile compounds are trapped in the highly polar and freezing solvent.

Formaldehyde and other carbonyls

A range of toxins is produced when a substance gets too hot. Smoke and vapor tests are therefore designed to analyze more than terpenes, cannabinoids, and VOCs according to Delic Labs.

Additionally, the other [use] of the impinger is to test for carbonyl compounds.


Carbonyls include aldehydes, like formaldehyde, which can be produced by various components of poorly designed vape pens and oils. Alternatively, aldehydes are naturally found in cannabis and contribute to the aroma and flavor. To test vape pens for this group of compounds, however, Delic Labs uses a different carcinogenic solvent known as DNPH.

The DNPH is used to derivatize the carbonyls that pass through the system. The derivatization allows the carbonyls to stay in the system instead of escaping.


Rather than a Gas Chromatography Mass Spectrometer, Delic uses a different method (HPLC) to detect any residual carbonyls collected after smoke or vapor bubbles through the DNPH solution.

Photo by Delic Labs.

A problem with lab tests

Bongs have evolved from O-ring to glass-on-glass for better airflow and function; similarly, vape pens still struggle with design flaws like faulty connections, for example. Pressure issues are further accentuated with the smoking and vaping machine used in Delic Labs, especially when it’s forced to percolate vapor through toxic solvents according to Sajni.

We found that connecting the impinger to our smoke machine does presently cause a lot of pressure issues. So, we have some problems where the solution doesn’t stay in the impinger and it gets sucked into the machine, instead. 


And not only that but, DNPH is an explosive compound, which Shah referred to as a limitation. For this reason, carbonyl testing was delayed to improve how the machine is set up to overcome those pressure issues and avoid damage and safety concerns within the lab.

Of course, this leaves out other toxins of concern. For Vitamin E acetate, Health Canada allows a limited quantity of vitamins to be added to vape pens as long as it mimics the formulation of a natural flavor. Heavy metals, however, are a problem only slightly less related to regulations. Thankfully, great improvements have been made to analyze heavy metals so expect a discussion on background noise and an exploration into recent advancements with lab tests.

Let us know what you think about vapor and smoke tests in the comments. Are you worried about toxins? But first, check out this story to learn more about the benefits that smoke and vapor tests offer consumers.