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From: Shawn Coleri
Sent: Tuesday, December 16, 2014
To: Rob Meagher
Subject: Re: CBE Week Issue 3

I have a question in regards to testing…..There are multiple different methods for testing marijuana and I imagine most of them are accepted. .my question lies with high pressure liquid chromatography (hplc) and gas chromatography with mass spectrometry (gcms)…The reason I bring this up is that most of the marijuana testing facilities seem to be using hplc. My guess it costs less to set the lab up. With it comes less repeatable results…less accuracy…here’s an excerpt I pulled that describes some differences…notice the last part of the comparison where it talks about manipulating the flow rate of the sample to change the end result.

What is the difference between HPLC and GC?

The major difference between GC and HPLC lies in the phases used. While in GC, compounds of a mixture are separated using a liquid (stationary) phase and a gas (mobile) phase, in case of HPLC the stationary phase is a solid while liquids make up mobile phase. Another difference lies in temperature control during the process. In GC, there is an oven to contain the column consisting of gas phase and it can control the temperatures when the gases are passing through the column. On the other hand, there is no such provision of temperature control in HPLC. The last difference pertains to the concentration of the compounds. In GC, it is the vapor pressure of the gases that decide the concentration of compounds whereas it is possible to increase or decrease the concentration of the compounds in HPLC.

The reason I bring this up is that I believe that some testing facilities are artificially manipulating the end cannabinoid numbers in an attempt to gain market share….higher numbers means more sales to retail stores which means you will use the lab that gives you the highest numbers. One of the dominant established labs in the Washington region have gone so far as to suggest to producers how to “clean” their product before they have it tested to guarantee a pass on the microbial screening. The problem is this is not how the product will go to market and they recommend submitting another sample for cannabinoid profiles which is highly unscrupulous.

I look forward to hear your thoughts.


Shawn Scoleri



CBE Response

Greetings, Shawn.

There are several points you touch on that are very relevant in understanding the current landscape of cannabis-centric laboratory testing facilities. Through all of the different legal cannabis markets, there are varying degrees of regulation and oversight on the different sectors of the cannabis industry. This includes laboratory testing facilities. As different states develop new regulations for legal cannabis it is important for state legislators and regulators to consider and define:

  1. Best practice and quality management system standards to follow
  2. Quality and technical accreditation process and who the accreditation body will be
  3. Which State agency will oversee and enforce laboratory licensure process
  4. Establishing specification limits for different product types (e.g. pesticide target list and residue limits)

The above considerations are the high level points, with significant underlying details. Some of those details include the standardization of testing methods that are used, which includes a validation process for the method in each laboratory facility. An appropriately executed validation process includes evaluation and documentation of a method’s repeatability, accuracy, linearity, and other relevant attributes. There are well established standards that define requirements for a validation process, of particular relevance to cannabis testing would be the USP <1225>, Validation of Compendial Procedures and ISO/IEC 17025:2005(E) Section 5.4.5. Validation of Methods. With appropriate validation of a testing method, it is acceptable for use. With this in mind, either GC or HPLC test methods can be validated and used accurately for, say, potency assay of cannabis flowers for cannabinoid content.

Method validation is just one of many underlying details that support a robust and reliable testing environment. I would encourage that all persons who intend to procure testing services do a bit of homework. A handful of good questions to ask would be:

  1. How long have you been operating?
  2. What quality standard do you follow?
  3. Are you accredited or in the process of being accredited to that standard?
  4. Where did you get your test methods from?
  5. Are they validated in your lab? (yes)
  6. How many chemists do you have working there? (equal to or greater than two)
  7. Is data peer reviewed? (yes)
  8. What type of equipment do you use?
  9. How many years has each operator used that type of equipment?
  10. Have you completed a proficiency test or round-robin with other labs? (yes, and they should have passed acceptance criteria)

It is unfortunate to think about your belief that some testing facilities are artificially manipulating the end cannabinoid numbers in an attempt to gain market share. Fortunately, by developing sound science and data-based regulation on cannabis-centric testing facilities that utilizes well established systems, models, and standards from similar industries, we can be assured that this practice will not persist if in fact it is occurring.

Along with regulation on a state level for testing facilities, it is critical that all industry participants and consumers of cannabis products in legal markets develop internal conversations about laboratory best practices and testing standardization. The development of industry groups that can bring various stakeholders to the table is critical. Of even greater criticality is that cannabis-centric testing facilities have direct conversations and begin to support local legislation and regulation with input of a harmonized, scientifically justified, voice.

Ultimately, the regulation of cannabis-centric testing facilities provides greater protection to the consumer of legal cannabis products and is a necessity for the successful progression of the industry.


Jeremy L. Sackett

Co-Founder and CEO, Cascadia Labs

4th of January, 2015

Cascadia Labs provides industry leading contract research and independent quality control testing services to the cannabis industry.   Our mission combines technical know-how with strong outreach efforts that provide science based information to local communities and policy makers. With two facilities currently operating, and the construction of a new flagship facility underway, Cascadia Labs is pleased to support the success of our colleagues during the ongoing expansion of regulated cannabis markets, both in Oregon and beyond.

Inquires can be made by calling 541.213.2315 or emailing [email protected]



Rob MeagherRob Meagher

Rob Meagher

Rob Meagher, CBE’s Founder, President and Editor-in-Chief is a 30 year veteran of the media world. His career has spanned from stints representing the Washington Post, USA Weekend, Reader’s Digest, Financial World & Corporate Finance to the technology world where he worked at International Data Group and Ziff Davis where he was part of the launch team for The Web Magazine, Yahoo Internet Life, Smart Business and Expedia Travels before starting his own marketing and Publisher’s Representative Firm. He also ran all print and online media sales and marketing for the Society for Human Resource Management before partnering with Forbes and then Fortune to create Special Sections covering a variety of topics. Rob, who started CBE Press in 2014, can be contacted at [email protected]

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