Cannabis testing in the US has made progress on multiple fronts but still has a long way to go, resulting in new opportunities for lab product and instrumentation companies. Testing demand is growing as more states legalize recreational use, and institute testing and lab requirements. But the fragmented market and unique business environment creates challenges for the fast-growing cannabis-testing market.

Legal sales of recreational cannabis began in the US states of Colorado and Washington in 2014. Recreational sales are scheduled to begin later this year in Oregon and in Alaska in 2016. In addition, 23 states and the District of Columbia (DC) permit the sale of cannabis for medical use. Initiatives for recreational use are expected to be on several state ballots in 2016, including California.

To ensure consumer safety and to meet labeling requirements, states are instituting or adding to testing requirements for medical and recreational cannabis. For example, Colorado requires that retail manufacturers of recreational-use cannabis edibles test for potency and homogeneity of active THC. Microbial- and residual solvent–contaminant testing is scheduled to begin this year. Washington requires potency and microbiological testing of recreational cannabis flowers, infused extracts for inhalation, edibles, liquids and topicals. Both states require labs to be certified for cannabis testing, with the first such labs certified in each state last year.

Cannabis consists of over 480 compounds, including 66 cannabinoids and 140 terpenes. To measure potency, samples are tested for selected cannabinoids, such as THC and CBD, and, in some cases, terpenes. GC, LC, SFC and TLC are used to quantify cannabinoids.

Cannabis is also tested for a wide range of contaminants. “Aflatoxins, mycotoxins, microorganisms, pesticides, heavy metals and residual solvents are the most commonly tested cannabis contaminants,” said Scott Kuzdzal, PhD, Life Science Business manager at Shimadzu Scientific Instruments (SSI). “The extent of contaminants depends on the greenhouse and storage, as well as the soil, fertilizers and methods growers used to control insects.”

Pesticide testing employs GC/MS and LC/MS, while mycotoxins can be measured using immunoassays or LC/MS. Testing for microorganisms utilizes qPCR or culture, while testing for heavy metals uses atomic spectroscopy techniques.

Because of limited regulation, other factors often determine for which contaminants testing is done. “Mold and microbiological contamination of plant material will most likely have the largest immediate impact on consumer safety, and these tests are relatively easy and inexpensive. Most laboratories offer this type of testing,” explained Amanda Rigdon, associate Product Marketing manager, GC Columns, at Restek. “Other contaminants testing is largely driven by state regulations, so the type of contaminant testing most in demand will differ by geographic region. The other two most common contaminant tests I see being investigated are residual solvents [from extraction] and pesticides.” GC is used to test for residual solvents.

For potency testing, HPLC is replacing GC. “HPLC is the most flexible technique and is capable of accurately measuring cannabinoid concentrations,” explained Dr. Kuzdzal. “GC analysis can only report ‘THC total,’ whereas HPLC can report both carboxylated and decarboxylated cannabinoids.” As Ms. Rigdon told IBO, “HPLC allows for straightforward, quantitative analysis of both the acidic and neutral cannabinoids at minimal cost. As the market matures, potency testing will still be required, and HPLC will continue to be the workhorse of the cannabis analytical lab.”

Emerald Scientific, a lab product distributor serving cannabis testing labs, has conducted two interlab-comparison proficiency tests. According to Ken Snoke, president of Emerald, “I guess it’s safe to say right now there is a trend away from GC toward LC for potency testing. Our recent proficiency test did show that HPLC performed better than GC in potency testing,” he explained. “However, GC is still needed for residual solvent testing and terpene testing. So I think it still has its place in the lab. It might just be used less and less for potency.”

MS is also expected to experience increased growth in this market due to greater pesticide testing. “As the cannabis testing market matures, it is likely that detection levels will decrease, requiring increased analytical sensitivity. Therefore, techniques that utilize MS (including LC/MS and GC/MS) will become more prevalent,” explained Dr. Kuzdzal. “These techniques are the most capable at determining the trace pesticides that could potentially contaminate the product.” As Ms. Rigdon commented, “Once regulations mature and become more clear regarding pesticides, I can see a growth opportunity for triple-quadruple instruments, including both LC- and GC-MS/MS, as these will be required to quantify low levels of pesticides in a complex matrix.”

A particular challenge for cannabis testing is sample preparation due to the types of samples that must be tested and the complexity of the plant itself. “The number one testing challenge is sample prep. This includes everything from extraction protocols and how to achieve good recoveries, to the use of disparate equipment such as various forms of blenders, homogenizers, etc.,” said Dr. Kuzdzal. “Labs are struggling with sample prep and need assistance with better protocols and automation.”

Shimadzu positions itself as a one-stop supplier, offering chromatography, atomic absorption spectrometry and MS solutions for cannabis testing. “Shimadzu delivers a complete solution to cannabis testing, including not only the instrumentation, but everything needed to start a cannabis testing laboratory, even financing,” said Dr. Kuzdzal.

Restek’s approach to the market is also comprehensive and attuned to the needs of new labs. The firm provides GC and LC columns as well as standards and sample preparation products. “Right now, Restek is supporting the cannabis industry and helping to improve testing quality by drawing on our expertise and experience in other markets—particularly food safety and pharmaceutical—to offer application support for most of the common chromatographic cannabis analyses, including potency, residual solvent and pesticide testing,” said Ms. Rigdon “We also offer free educational opportunities geared toward advancing chromatographic techniques for the cannabis testing market.”

The cannabis testing market’s development both stimulates the need for testing products and expertise, as well as creates business and testing challenges. Complicating the market’s development are the unique circumstances under which labs operate, including business constraints, such as federal banking laws, and a patchwork of state and local legal requirements.

Most of the labs are newer and specialize in cannabis testing. “The relatively high-legal-risk nature of cannabis testing has resulted in a huge percentage of the market being made up of start-up labs run by passionate and driven individuals who (for the most part) established their labs to ensure cannabis consumer safety,” explained Ms. Rigdon. “This means that this new market is entirely new—it’s not made up of laboratories established in other industries branching out into medical cannabis. Because of this, the industry is on its way up a steep analytical learning curve, and is making very good progress toward robust analytical methods to ensure consistent and safe cannabis products.” Dr. Kuzdzal told IBO, “Regulations, certification processes and licensing fees currently vary across the 23 states (plus DC) that have legalized medicinal marijuana. There still remains great discrepancies in state versus federal laws that adds great confusion, uncertainty and malaise to the cannabis testing market.”

State-by-state and even local variation in requirements impact testing quality. The lack of standardized testing methods or lab-certification process, as well as vague or nonexistent testing guidelines and regulations, has compromised testing quality. Although states are gradually implementing testing regulations, there is still much disparity.

In many cases, the initiative of individual labs has filled the gap. Asked to characterize the cannabis testing industry, Mr. Snoke told IBO, “I’m impressed. . . . It’s not regulated from any regulatory agency or body. But considering that it’s a new industry that is growing up without the benefit of any support from FDA, USDA or any other agency, I think everybody is doing a pretty good job.”

Advancements include the commercial availability of cannabis standards. He noted that many of the testing discrepancies found in his company’s initial proficiency testing have improved due to the availability of standards. Emerald also provides custom mixes for calibration standards. As with SSI and Restek, Emerald’s role involves a comprehensive approach, including sponsoring an annual conference about cannabis testing.

The market is also progressing as labs seek accreditation. “I think it is really clear that . . . things like ISO 17025 accreditation will be required. We’re starting to see that in some of the legal states,” explained Mr. Snoke. “So a lot of the analytical labs are heading in that direction basically because they know it is coming.” ISO certification is also recommended by the Association of Commercial Cannabis Laboratories (ACCL), an organization of 22 medical marijuana–testing labs from different states. “One of the things the ACCL is trying to do is help set the easy standards for quality assurance. Quality assurance measurements should be easily understood by anyone looking at it,” said Robert Martin, PhD, executive director of the ACCL. Members are also required to participate in a ring test to establish competence.

Other constraints on cannabis testing labs include cost, both for lab operators and customers. “People in the industry realize we need this kind of quality assurance mechanism. . . . So, I preach to our labs at the same time that we have to find a way to make it more affordable for our clientele rather than more expensive,” said Dr. Martin. As Mr. Snoke put it, “For sure you need GC/MS/MS or LC/MS/MS for pesticide testing. Folks aren’t that well funded. These are mostly, not all, a lot of mom-and-pop style labs. People that just start up. So affording the appropriate equipment has been a challenge. That’s really not a scientific challenge, but it creates one because they are trying to do things with suboptimal instrumentation.”