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

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

Steam containment in the laboratory

As a Health Canada approved research laboratory on the UBC campus, Delic Labs is licensed to test cannabis as well as psilocybin. They offer unique tests like a smoke and vapor analysis which, as Delic Labs described in a previous report, is capable of guiding the design and experience of vaping.

The final product must be tested for a correct result, and according to Dr. Markus Roggen, President and CSO of Delic Labs, the end product for a vape pen is vapor. To do this, laboratory tests can make sure a vape pen is delivering a good dose and taste, as well as determining if it is toxic.

A machine just puffs on a vape pen or a burning joint and the data is quantified – right?

If you ask an expert, there are many challenges behind the scenes that have led to much advances in this new type of laboratory test. There are currently three main test courses for smoke and steam available, with more in preparation.

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

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

Extracting these filter mats allows us to get relatively good quality [and quantitative] work on cannabinoids and terpenes.

Sajni Shah, Laboratory Manager, Delic Labs.

With this simpler test, things are still straightforward – a tool used, for example, to maintain consistency and tune the dose of each puff. However, the safety of vape pens is more complex than cannabinoid cans. Cannabis oils, especially terpenes, produce a potential slurry of toxins when exposed to excessive heat – an important catalyst for molecular change.

So we want to test for these toxins, and that’s where it gets more complicated.

Sajni

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

Determine the amount of Volatile Organic Compounds in vape pens

To capture lighter connections, Delic Labs uses an impinger. Imagine a small laboratory-style bong that steam or smoke can be drawn through. Aside from the fact that Delic Labs percolates their smoke and steam through methanol – a toxic solvent – to collect volatile organic compounds (VOCs) for later analysis. VOCs include, for example, isoprene, benzene, toluene and other light toxins.

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

Sajni

A special test known as gas chromatography-mass spectrometry (GC-MS) is then used to quantify the residual toxins once these volatile compounds are trapped in the highly polar and freezing solvent.

Formaldehyde and other carbonyls

When a substance gets too hot it creates a number of toxins. According to Delic Labs, smoke and steam tests should therefore analyze more than terpenes, cannabinoids and VOCs.

Besides, the others [use] of the impinger is to be tested for carbonyl compounds.

Sajni

Carbonyls include aldehydes such as formaldehyde, which can be produced by various components of poorly designed vape pens and oils. Alternatively, aldehydes occur naturally in cannabis and add to its aroma and taste. However, to test vape pens for this group of compounds, Delic Labs uses another cancer-causing 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.

Sajni

Instead of a gas chromatography mass spectrometer, Delic uses a different method (HPLC) to detect any carbonyl residues collected after smoke or vapor bubbles through the DNPH solution.

Photo by Delic Labs.

A problem with laboratory tests

Bongs have evolved from O-ring to glass-on-glass for better airflow and function; Likewise, vape pens still struggle with design flaws such as bad connections. Pressure issues are further accentuated with the smoke and steam engine used at Delic Labs, especially when it is forced to seep steam through toxic solvents, according to Sajni.

We have found that connecting the impinger to our fog machine is currently causing a lot of printing problems. So we have some problems where the solution doesn’t stay in the impinger and instead is sucked into the machine.

Sajni

Not only that, DNPH is an explosive compound that Shah referred to as a limitation. Because of this, the carbonyl tests have been postponed to improve the machine’s setup to overcome these printing issues and avoid damage and safety concerns in the laboratory.

This, of course, leaves out other worrying toxins. For Vitamin E Acetate, Health Canada allows a limited amount of vitamins to be added to vape pens as long as it mimics the formulation of a natural taste. Heavy metals, on the other hand, are only a slightly less regulatory problem. Fortunately, great improvements have been made in the analysis of heavy metals. So expect a discussion of background noise and an examination of recent advances in laboratory testing.

Let us know what you think of vapor and smoke tests in the comments. Are you worried about toxins? But look at this first story to learn more about the benefits smoke and vapor testing can bring to consumers.