How Can Colorado Cannabis Labs Prepare for Vapor Testing?

Come January 1, 2022, cannabis labs in Colorado will be required to perform to test the actual vapor emissions from cannabis e-cigarette and vape devices, not just the oils stored within.

However, this vapor test is not expected to be a straightforward addition to the state’s current testing regimen. While vapor testing methodologies and machines already exist for tobacco e-cigarettes, this is uncharted territory for the cannabis sector. So, with less than six months to go until this new requirement is rolled out, how can Colorado’s testing facilities prepare?

Vapor testing and Colorado’s new requirements

This new testing rule was officially added to the state’s cannabis regulations in October 2020, giving laboratories just over a year to adapt.

The rule states that, “Each Harvest Batch and Production Batch of Regulated Marijuana Concentrate in a Vaporized Delivery Device must be tested for metals contamination via emissions testing by a Regulated Marijuana Testing Facility.”

“The metals contamination test must include, but need not be limited to, testing to determine the presence and amounts of arsenic, cadmium, lead, and mercury,” it continues.

This rule was proposed by the testing subcommittee of the Colorado’s Marijuana Enforcement Division (CMED), who argued that checking the emissions of these vape devices is far more relevant to consumer and public health than simply testing the vape liquids contained within. Since it is not yet fully understood how heavy metal contaminants in cannabis vape oil might behave under the operating conditions of these devices, directly testing the vapor emitted should give a more complete picture of the risks that a consumer could be exposed to.

“Ultimately, when you’re vaping it changes the chemistry of what is in your vape cartridge,” Kyle Boyar, vice chair of the American Chemical Society’s Cannabis Chemistry Subdivision [CANN], told Analytical Cannabis.

“There's a lot of byproducts and things that we don't really fully understand. I know Dr Roggen [of DELIC Labs] has done a lot of work on this, looking at some of those harmful and potentially harmful constituents that do come off of the vapor. I think it is really important to do [vapor testing] because, yes, you can test the product and see what it is like pre-vaping, but without knowing what it looks like in that vapor stream you really don’t know what you’re getting.”

The difficulty with vapor testing in cannabis

These four metals – arsenic, cadmium, lead, and mercury – will be the main focus of this new testing regimen. But should they be? Just as it is unclear exactly how heavy metal contaminants might behave within cannabis vapes, more research is needed to determine exactly what the main risks in cannabis vapor might be.

“The cartridge devices themselves generally don’t have those four metals in them. There is sometimes a small amount of lead, but the other three metals generally aren’t found in these vape cartridges,” Dr Amber Wise, scientific director at Medicine Creek Analytics and CANN member, told Analytical Cannabis.

The heating elements of these devices are normally made from nichrome or nickel, Wise explained. Similarly, the metal cartridges themselves are often made from brass, which is an alloy of copper and zinc. These cartridges might also contain nickel or stainless steel, which can be doped with a variety of other different metals.

“So it’s arguable that we should be looking at anything but the big four,” Wise said. “In this situation, if we're trying to figure out the contribution of the cartridges themselves to our metals exposure, we should look at what the cartridges are made out of and look for those metals.”

Of course, if additional risks due to the presence of these metals are proven, there is no reason to say the regulators would not move to include them as soon as possible. The exact wording of the legislation does stress that the test “must include, but need not be limited to” those four metals.

Perhaps a more important consideration is methodology. In the tobacco industry, there already exists multiple different apparatus that are capable of producing and screening vapor streams from e-cigarette products. But cannabis is an extremely complex matrix with different properties to tobacco, and so there is no guarantee that these methods will directly translate over to cannabis vapor testing.

“The standard way to collect gaseous molecules is to bubble [the gas] through impingers. These impingers are little glass tubes with frayed glass at the end, to make very small bubbles,” said Wise.

“The idea there is that whatever is in the gaseous phase, you want those bubbles to be small so that there’s a high surface-area-to-liquid ratio. Those molecules that you’re trying to capture are dissolving in that liquid that is bubbling through.”

“[But for cannabis vapors] these impingers would just get clogged up with cannabis oil as it condenses back down to these oily droplets. It just would clog up the system and then we wouldn’t be able to pull air through very well,” Wise explained. “There’s just a bunch of logistical things that aren’t the case for e-cigarettes.”

Will Colorado’s laboratories be ready in time?

Back when the new rule was announced in early October 2020, labs were given just under 15 months to prepare for the new changes. So, with less than six months left, how are they doing?

“We plan to start working on cannabis vapor emissions testing in the summer,” Alena Rodriguez, the managing director of Boulder-based Rm3 Labs, told Analytical Cannabis earlier this year.

“The Science and Policy Work Group Testing Subcommittee has an expert on the team that has been working on vapor emissions testing and will be providing information to the Colorado labs to help us choose instrumentation and methods,” she added.

While some in the industry are confident that Colorado’s cannabis labs will be well-prepared come January 1, others are more reserved.

“Cannabis oil is a completely different matrix, you have to do a lot of different testing to figure out what works and what is optimal,” Boyar said. “Truth be told, in Colorado – and I have not discussed with the state what they’re planning on doing exactly – I have not seen any of these methods put [out] publicly as far as what they plan on doing. And what’s really concerning is, if you don’t have a standardized method for how you’re going to do this across all these different labs, well then, what are you really asking the testing labs to do?

“It’s a great idea and I think it’s very important that we do this,” Boyar added. “I mean, people are using this as medicine – they’re already immunocompromised, many of them – so we really should be doing this. But, again, if you have no protocol established and you don’t have validated methods, then you’re really asking them to do something that’s really not going to give you repeatable results. And that’s what we’re hoping to get towards, this consistency from lab to lab.”

This article originally appeared in Analytical Cannabis' Advances in Cannabis Testing eBook in September 2021.