Cannabis Lab Testing: How it Works and Why it Matters

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Is the cannabis that you’re consuming lab tested? If not, it definitely should be.

Read more to find out why.

Why Does Cannabis Need to be Lab Tested?

Professional lab testing ensures the potency and safety of cannabis products whether they be flowers, edibles, or concentrates like cannabis oil vape cartridges and dabbing extracts.

If you’re buying recreational or medical marijuana, the only real way to know the quality of what you’re consuming is through analytical testing.

Kurvana ASCND vape cartridges
Cannabis packing should clearly show lab tested results.

Lab Testing for Cannabis Potency

As part of professional lab testing, the potency of a cannabis product is evaluated by measuring:

  • The amount of THC in the product
  • The amount of CBD in the product
  • The ratio of THC to CBD in the product

While many compounds make up a particular cannabis strain’s terpene and cannabinoid profile, these are the primary cannabinoids required to appear on a certificate of analysis (COA) according to California regulations

Users that want a pure CBD product that is free of any THC will definitely want to turn to something like industrial hemp-derived CBD products and CBD isolates. The purity of CBD in these products should be tested to show less than 0.3% THC, backed by a reputable lab’s certificate of analysis.

Testing of potency is important because consumers seek different effects from cannabis products.

Some cannabis users desire a high from their product. Products containing a large amount of THC are probably best for these particular users.

On the other hand, some medical cannabis users want to avoid the high effect. They desire alternative medicinal benefits from their cannabis products. These users are typically better off with a product that has a high CBD to THC content. Others may want pure a CBD product.

Users that want a pure CBD product that is free of any THC will definitely want to turn to something like industrial hemp-derived CBD products and CBD isolates. The purity of CBD in these products should be tested to show less than 0.3% THC, backed by a reputable lab’s certificate of analysis.

If you’re not getting the expected effects from your CBD and cannabis products, check the label or lab report. You may discover your cannabis product doesn’t contain the right dosage of cannabinoids or terpenes you were expecting.

By accurately testing potency, labs help to ensure consumers get the desired effects from their choice of cannabis products. When you understand how much THC is in your products, you can properly dose to avoid getting too high.

Cannabis Lab Testing for Safety

In addition to evaluating the potency of cannabis products, professional labs also run pesticide screening and test the safety of the product.

Using different technologies, labs will test for, among other possible contaminants:

  • Pesticides, such as glyphosate, boric acid, and DDT
  • Solvents, such as butane and propane
  • Mold, such as Cladosporium and Botrytis
  • Bacteria, such as E. coli and Penicillium
  • Heavy metals, such as lead and mercury

Further, professional labs will identify whether or not a cannabis product contains the controversial additives propylene glycol (PG) and polyethylene glycol (PEG).

Dr. Dabber cbd lab tests
Certificate of Analysis for Dr. Dabber CBD oils.

How Cannabis Lab Testing Works 

Professional labs use a handful of complex, high-tech instruments and pieces of equipment in order to run a comprehensive battery of tests on cannabis products. 

The two primary methods of testing are gas chromatography (GC) and high-performance liquid chromatography (HPLC).

Gas chromatography (GC)

Performed with a device called a gas chromatometer, gas chromatography (GC) is used to analyze terpene profiles of cannabis products and detect the presence of pesticides and residual solvents.

GC works for volatile substances, which are substances that are capable of being vaporized. But, not all substances are capable of being vaporized.

GC is also used to determine the potency of cannabis products, by measuring the levels of THC and CBD in the product.

The lab report must specify the percentage of the following cannabinoids for each tested sample:

  • THC
  • THCA
  • CBD
  • CBDA

Further, the lab report needs to indicate the percentage of total THC and total CBD.

High-performance liquid chromatography (HPLC)

High-performance liquid chromatography, or HPLC, is a complementary test to GC, discussed above.

HPLC works for substances that cannot be vaporized, but are soluble, that is, capable of being dissolved.

Like GC, HPLC is used to determine terpene profiles and detect pesticides and residual solvents in cannabis products.

SC Labs PhytoFacts Charts
Source: SC Labs

SC Labs has a great guide on their website that explains how to interpret lab results and understand the COA.

Lab Testing Regulations for Licensed Brands in California

Regulation of the legal sale of cannabis products is left up to each individual State. At the Federal level, cannabis is still illegal and, therefore, is not regulated by the United States Government.

In California, one of the biggest States to legalize the sale of cannabis, the legal sale of cannabis products is regulated by the Bureau of Cannabis Control (BCC)

As of January 2021, the BCC requires all cannabis products to be tested for the following:

  • Cannabinoids
  • Pesticides
  • Microbes
  • Terpenoids
  • Mycotoxins
  • Heavy metals

The BCC has established thresholds that determine whether a sample test passes or fails.

For example, with respect to the heavy metal “mercury”: the sample of an inhalable (smokeable) good passes if the mercury content of the sample is 0.2 micrograms or less per gram.

For other, non-inhalable cannabis products, the test passes if there is 3.0 micrograms or less per gram.

If a sample from a product batch fails, the batch cannot be sold.

Depending on the product, additional testing might be required. For example, edible cannabis products are required to be tested for homogeneity, that is, that the contents of the product are uniform throughout the product.

In Colorado, another large State that has legalized the sale of cannabis, the legal sale of cannabis is regulated by the State Licensing Authority of the Colorado Department of Revenue, Marijuana Enforcement Division.

The testing requirements in Colorado, compared to the testing requirements in California, are much more stringent. 

In addition to the substances required to be tested for in California, listed above, Colorado also requires cannabis products to be tested for:

  • Vitamin E acetate
  • Polyethylene glycol (PEG)
  • Medium-chain triglycerides (MCT)
  • And other substances…

Requirements to Start a Cannabis Testing Lab

Yet, like any other business, there is no guarantee that the cannabis testing lab will bring in money. Unfortunately, the pursuit of a profit leads some labs to produce fraudulent test results.

Starting a cannabis testing lab is far from being a simple process.

First, as is the case when starting any business, many comprehensive plans need to be developed and put in writing. Some examples of these plans include:

  • Overall business plan
  • Operational plan
  • Marketing plan

Second, financing will need to be obtained in order to get the business off the ground.

Will the cannabis testing laboratory be financed by investors? By borrowing money?

Many banks and other financial institutions will not loan money to businesses in the cannabis space.

Investors in a cannabis testing lab, or in any legally-operating cannabis business, can expect to be thoroughly background checked. When government officials are conducting these background checks, they will be looking for criminal convictions, lawsuits, and other evidence that suggests the investor lacks good moral character.

Third, after writing up business plans and obtaining financing, the “cannabis part” of opening up the testing lab can begin.

The requirements for starting a cannabis testing lab are very complex and vary from state to state.

In California, the Bureau of Cannabis Control (BCC) will require and need to approve, among many other things:

  • facility design plans
  • lab operations plans
  • lab quality assurance plans
  • standard operating procedures (SOPs)

Only after the BCC has given its stamp of approval can the cannabis testing lab start accepting new customers.

Yet, like any other business, there is no guarantee that the cannabis testing lab will bring in money. Unfortunately, the pursuit of a profit leads some labs to produce fraudulent test results.

Reputable Testing Labs

Almost all cannabis testing labs are reputable and provide accurate test results. The reality is, however, there are some labs that do not provide reliable test results. This might happen innocently. But, it might also happen maliciously.

The cost to build a cannabis testing lab with the most precise, state-of-the-art equipment, can easily cost $500,000 or more. In order to avoid that substantial cost, some labs will instead purchase older-generation, less sensitive equipment.

Because older equipment is less sensitive than newer equipment, the test results, while produced with the best intentions, are not always reliable.

Some labs are willing to fudge or fake test results because it is hard for legitimate cannabis testing labs to be profitable. It is not uncommon for cannabis testing labs to be $500,000 or more for equipment, but only be testing 3 or 4 samples per day, at a cost of $100 or less per sample. Since it is impossible for the lab to be profitable operating this way, the lab will accept payments (in essence, bribes) to provide passing tests.

Steep Hill Labs and SC Labs are two of the leading cannabis testing labs in the U.S. Other cannabis labs that produce trustworthy, valid test results are ISO/IEC 17043 accredited. Labs that meet ISO/IEC 17043 have demonstrated that their equipment is properly calibrated to internationally-recognized standards. 

Further, labs that meet ISO/IEC 17043 have demonstrated that they competently perform sampling, testing, and regular calibration of lab equipment.

As the cannabis industry continues to mature, more states will legalize cannabis and impose stricter testing regulations. This is ultimately a great step forward as it leads to increased transparency and consumer safety.

Are your favorite vape brands lab tested? When in doubt, ask for the lab results. Be an educated cannabis user and know what you’re consuming.

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Cody B
Cody B

I am a professional writer located in Los Angeles, California. I cover topics related to the cannabis industry, technology, business, and politics. You can see some of my other work on my personal website.

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