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Standards from Chaos - Clarifying Diagnostic Testing within the Cannabis Industry

A (Very) Brief Overview

Diagnostic laboratory testing is a well-refined science. Validated and reliable testing processes exist for determining everything from the structures of the smallest components of matter to the purity of water you drink. The results of those processes can inform consumer decisions to eat certain foods, take medication, or drink bottled water; testing results for purity, and potency can cause a consumer to choose one product over another, and a manufacturer to favor using a certain laboratory for product potency testing, if that laboratory produces favorable results.

The following five-part series (including insight from expert, multi-industry diagnostic laboratory professionals), defines the purpose, ideal processes, and outcomes of diagnostic testing within the cannabis industry, providing invaluable insight to all – whether a buyer, or seller of products or services. This introduction serves to set the groundwork so anyone might better understand the processes by which consumer products are tested (especially those without a background in the sciences).

Start with Structure

Standard Operating Procedures (SOPs) by which samples are collected and analyzed in the medical and consumer foods markets are widely and generally accepted by each respective analytical diagnostic community. Established SOPs contain steps which, if followed in sequence, allow for highly specific, interpretable data, and result in consumer (or patient) safety, and can be repeated in any diagnostic laboratory of the same caliber. To further ensure those processes are sound, established industries also generally require diagnostic laboratories to carry accreditation in the form of Good Manufacturing Practices (GMPs), ISO 15189 (medical), or ISO 17025 (multiple industries, including cannabis) certifications. SOPs and certifications in place, diagnostic laboratories should produce results which are both valid and reliable (which is the standard for any scientific experiment).

Two Gold Standards of Science: Validity and Reliability

Validity means an experiment measures what it should. For example, if conducting a test to determine if a softball is hard, but the result of your experiment only proves that it is white, the test is not valid. If, however, your experiment proves the softball is soft as a ball of Jell-O, your experiment is valid – it proved the softball is not hard.

Reliability is complementary to validity, and means a test can be repeated in almost exactly the same manner, to produce a desired result; in the laboratory, if an experiment can be repeated to show the same result with known inputs, then it is deemed reliable; reliability means repeatability of process.

To ensure results from laboratories are both valid and reliable, standards are used. A standard is a material which has already been tested by a reference laboratory to prove a certain chemical composition. Relative to the cannabis industry, a standard material containing a certain percentage of THC already known would be sent by a reference lab to a commercial lab for testing. The commercial lab, free to use any internal SOP and equipment they like (historically true for states in which THC lab shopping proliferated), MUST report the expected result (THC concentration) by the same valid, and reliable processes it uses to test customer samples. If the reported results are inaccurate, imprecise, out of range (consistently too high or low), or outside a known reference range, corrective action must be taken. Correction may involve updating SOPs, recalibrating equipment, or training, but must be completed for accurate reporting of standard results PRIOR to commercial testing.

The Cannabis Industry Problem with Validity

This concept is a complicated one, in that while valid test results are ones which measured what they should, if the sample tested does not represent the target (a population or batch), it is likewise not valid – though a test for mold may reliably measure potential contaminants, if the sample was collected before it was contaminated, a negative result does not mean the batch will be mold-free after additional handling. Cannabis industry testing standards often produce such results, as they do not test the product which matters – the end-product. To fully appreciate the problem, we need to define the difference between an intermediary product (which is most commonly tested), and the end product ingested by the consumer.

Intermediary products are those used to create other products. If you are baking a cake (which will be your end-product), you combine eggs, butter, flour, and sugar to form batter first. All those products (first, the eggs, butter, flour, and sugar, and then the batter, after they are combined) are intermediary products – they are used to create another, final product – the cake. Alternatively, the end-product in this analogy, is the cake; it is the final form product which is consumed – nothing more is added or taken away from the end-product, and it exists in a completely post-processed state.

As you can likely infer, the testing problem within the cannabis industry is one which stems from a misunderstanding of what constitutes an “end-product.” Formerly, multiple states’ regulatory requirements stated only batch-level flower product must be tested for potential contaminants, including yeast and mold. This requirement completely ignored the conversion of that tested product (an intermediary) into a final product (a post-trim, handled, and packaged product). The problem was not necessarily that testing for contaminants was (or is) inaccurate, but that the test was (or is) being applied at the wrong stage of the process. If the goal is to ensure safety of the consumer, the end-product (post-packaging) is the only one which should be tested (and this is already the standard for other consumables, such as oils). Additionally, if a post-handled product is re-tested and proved to contain mold, the liability cannot be transferred to the testing laboratory, as it did not test the final, shelf product.

The Cannabis Industry Problem with Reliability

When a lab tests for THC content using a method standardized by a governing body or regulatory agency, then decides to utilize a new method (perhaps because it is less costly, or more efficient), that new method must produce valid and reliable results. That updated method (or SOP) would be generally considered valid (as it would measure what was intended to be analyzed – THC content) with little contention, but would be considered unreliable if the standard method produced a result of 20% THC content, whereas the updated method showed a 50% THC content for the same sample. Unfortunately, within an industry which prizes high THC content labeling, growers are financially incentivized to utilize the services of laboratories which inflate THC content results (potentially via unapproved methods). Unless those laboratories are audited and caught reporting inflated results, however, the cycle wreaks havoc on the economic landscape of the entire industry by devaluing quality product at the expense of high-velocity, chemically inferior product, while driving business to laboratories engaging scientifically unsound processes.

What Comes Next?

Before discussing how corrective action can be applied to the cannabis industry from a multi-industry comparative standpoint to ensure safety and economic viability, it is critical to understand the three phases of the testing process to fully appreciate how we arrived here.

Generally referred to as the Total Testing Process (TTP) within the medical field, the three phases of diagnostic laboratory testing, and their three most important subcomponents, include:

  1. Pre-Analytical

    1. Sample Collection

    2. Sample Receiving

    3. Sample Preparation

  2. Analytical

    1. Testing Methodologies

    2. Proficiency Testing

    3. Instrument Performance

  3. Post-Analytical

    1. Interpretation

    2. Reporting/Resulting

    3. QA/QC

The unifying element of the three key phases of the Total Testing Process is the Standard Operating Procedure (SOP), which standardizes the actions required for a laboratory configured in any manner to produce valid and reliable results.

Part II of this series, Standards from Chaos: Clarifying Diagnostic Testing within the Cannabis Industry, will define elements of the Pre-Analytical phase during which most process errors are likely to occur, include comparison of multi-state regulatory requirements, and define the process elements least considered by growers, and most likely to result in ethical, accurate reporting.

Reviewed by Debra Sneed – MT (AMT/ASCP), MLS (ASCP), a Clinical Laboratory Scientist and laboratory generalist of 40-years-experience operating laboratories in Michigan, Indiana, Texas, Alaska, Virginia, South Dakota, and Kansas.

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