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Dr. Ed Askew
From The Lab

Quality Plans for Lab Services: Managing Risks as a Grower, Processor or Dispensary, Part 3

By Dr. Edward F. Askew
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Dr. Ed Askew

Editor’s Note: The views expressed in this article are the author’s opinions based on his experience working in the laboratory industry. This is an opinion piece in a series of articles designed to highlight the potential problems that clients may run into with labs. 


In the last two articles, I discussed the laboratory’s first line of defense (e.g. certification or accreditation) paperwork wall used if a grower, processor or dispensary (user/client) questioned a laboratory result and the conflicts of interest that exist in laboratory culture. Now I will discuss the second line of defense that a laboratory will present to the user in the paperwork wall: Quality Control (QC) results.

Do not be discouraged by the analytical jargon of the next few articles. I suggest that you go immediately to the conclusions to get the meat of this article and then read the rest of it to set you on the path to see the forest for the trees.

QC in a laboratory consists of a series of samples run by the laboratory to determine the accuracy and precision of a specific batch of samples. So, to start off, let’s look at the definitions of accuracy and precision.QC Charts can provide a detailed overview of laboratory performance in a well-run laboratory.

According to the Standard Methods for the Examination of Water and Wastewater:

Accuracy: estimate of how close a measured value is to the true value; includes expressions for bias and precision.

Precision: a measure of the degree of agreement among replicate analyses of a sample.

A reputable laboratory will measure the Accuracy and Precision of QC samples in a batch of user samples and record these values in both the analytical test report issued to the user and in control charts kept by the laboratory. These control charts can be reviewed by the user if they are requested by the user. These control charts record:

Accuracy (means) chart: The accuracy chart for QC samples (e.g., LRB, CCV, LFBs, LFMs, and surrogates) is constructed from the average and standard deviation of a specified number of measurements of the analyte of interest.

Precision (range) chart: The precision chart also is constructed from the average and standard deviation of a specified number of measurements (e.g., %RSD or RPD) for replicate of duplicate analyses of the analyte of interest.

Now, let’s look at what should be run in a sample batch for cannabis analyses. The typical cannabis sample would have analyses for cannabinoids, terpenes, microbiological, organic compounds, pesticides and heavy metals.

Each compound listed above would require a specific validated analytical method for the type of matrix being analyzed. Examples of specific matrixes are:

  • Cannabis buds, leaves, oil
  • Edibles, such as Chocolates, Baked Goods, Gummies, Candies and Lozenges, etc.
  • Vaping liquids
  • Tinctures
  • Topicals, such as lotions, creams, etc.

Running QC analyses does not guarantee that the user’s specific sample in the batch was analyzed correctly.

Also, both ISO 17025-2005 and ISO 17025-2017 require the use of a validated method.

ISO 17025-2005: When it is necessary to use methods not covered by standard methods, these shall be subject to agreement with the customer and shall include a clear specification of the customer’s requirements and the purpose of the test and/or calibration. The method developed shall have been validated appropriately before use.

ISO 17025-2017: The laboratory shall validate non-standard methods, laboratory-developed methods and standard methods used outside their intended scope or otherwise modified. The validation shall be as extensive as is necessary to meet the needs of the given application or field of application.

Validation procedures can be found in a diverse number of analytical chemistry associations (such as AOACand ASTM) but the State of California has directed users and laboratories to the FDA manual “Guidelines for the Validation of Chemical Methods for the FDA FVM Program, 2nd Edition, 2015

The laboratory must have on file for user review the following minimum results in an analytical statistical report validating their method:

  • accuracy,
  • limit of quantitation,
  • ruggedness,
  • precision,The user must look beyond the QC data provided in their analytical report or laboratory control charts.
  • linearity (or other calibration model),
  • confirmation of identity
  • selectivity,
  • range,
  • spike recovery.
  • limit of detection,
  • measurement uncertainty,

The interpretation of an analytical statistical report will be discussed in detail in the next article. Once the validated method has been selected for the specific matrix, then a sample batch is prepared for analysis.

Sample Batch: A sample batch is defined as a minimum of one (1) to a maximum of twenty (20) analytical samples run during a normal analyst’s daily shift. A LRB, LFB, LFM, LFMD, and CCV will be run with each sample batch. Failure of any QC sample in sample batch will require a corrective action and may require the sample batch to be reanalyzed. The definitions of the specific QC samples are described later.

The typical sample batch would be set as:

  • Instrument Start Up
  • Calibration zero
  • Calibration Standards, Quadratic
  • LRB
  • LFB
  • Sample used for LFM/LFMD
  • LFM
  • LFMD
  • Samples (First half of batch)
  • CCV
  • Samples (Second half of batch)
  • CCV

The QC samples are defined as:

Calibration Blank: A volume of reagent water acidified with the same acid matrix as in the calibration standards. The calibration blank is a zero standard and is used to calibrate the ammonia analyzer

Continuing Calibration Verification (CCV): A calibration standard, which is analyzed periodically to verify the accuracy of the existing calibration for those analytes.

Calibration Standard: A solution prepared from the dilution of stock standard solutions. These solutions are used to calibrate the instrument response with respect to analyte concentration

Laboratory Fortified Blank (LFB): An aliquot of reagent water or other blank matrix to which known quantities of the method analytes and all the preservation compounds are added. The LFB is processed and analyzed exactly like a sample, and its purpose is to determine whether the methodology is in control, and whether the laboratory is capable of making accurate and precise measurements.

Laboratory Fortified Sample Matrix/Duplicate (LFM/LFMD) also called Matrix Spike/Matrix Spike Duplicate (MS/MSD): An aliquot of an environmental sample to which known quantities of ammonia is added in the laboratory. The LFM is analyzed exactly like a sample, and its purpose is to determine whether the sample matrix contributes bias to the analytical results. The background concentrations of the analytes in the sample matrix must be determined in a separate aliquot and the measured values in the LFM corrected for background concentrations (Section 9.1.3).Laboratories must validate their methods.

Laboratory Reagent Blank (LRB): A volume of reagent water or other blank matrix that is processed exactly as a sample including exposure to all glassware, equipment, solvents and reagents, sample preservatives, surrogates and internal standards that are used in the extraction and analysis batches. The LRB is used to determine if the method analytes or other interferences are present in the laboratory environment, the reagents, or the apparatus.

Once a sample batch is completed, then some of the QC results are provided in the user’s analytical report and all of the QC results should be recorded in the control charts identified in the accuracy and precision section above.

But having created a batch and performing QC sample analyses, the validity of the user’s analytical results is still not guaranteed. Key conclusion points to consider are:

  1. Laboratories must validate their methods.
  2. Running QC analyses does not guarantee that the user’s specific sample in the batch was analyzed correctly.
  3. QC Charts can provide a detailed overview of laboratory performance in a well-run laboratory.

The user must look beyond the QC data provided in their analytical report or laboratory control charts. Areas to look at will be covered in the next few articles in this series.

Top 10 Common Findings Detected During Cannabis Laboratory Assessments: A Guide to Assist with Accreditation

By Tracy Szerszen, Tracy Szerszen
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With the cannabis industry growing rapidly, laboratories are adapting to the new market demand for medical cannabis testing in accordance to ISO/IEC 17025. Third-party accreditation bodies, such as Perry Johnson Laboratory Accreditation, Inc. (PJLA), conduct these assessments to determine that laboratories are following relevant medical cannabis testing standard protocols in order to detect potency and contaminant levels in cannabis. Additionally, laboratories are required to implement and maintain a quality management system throughout their facility. Obtaining accreditation is a challenge for laboratories initially going through the process. There are many requirements outlined in the standard that laboratories must adhere to in order to obtain a final certificate of accreditation. Laboratories should evaluate the ISO 17025 standard thoroughly, receive adequate training, implement the standard within their facility and conduct an internal audit in order to prepare for a third-party assessment. Being prepared will ultimately reduce the number of findings detected during the on-site assessment. Listed below is research and evidence gathered by PJLA to determine the top ten findings by clause specifically in relation to cannabis testing laboratories.

PJLA chart
The top 10 findings by clause

4.2: Management System

  • Defined roles and responsibilities of management system and its quality policies, including a structured outline of supporting procedures, requirements of the policy statement and establishment of objectives.
  • Providing evidence of establishing the development, implementation and maintenance of the management system appropriate to the scope of activities and the continuous improvement of its effectiveness.
  • Ensuring the integrity of the management system during planned and implemented changes.
  • Communication from management of the importance of meeting customer, statutory and regulatory requirements

4.3: Document Control

  • Establishing and maintaining procedures to control all documents that form the management system.
  • The review of document approvals, issuance and changes.

4.6: Purchasing Services and Supplies

  • Policies and procedures for the selection and purchasing of services and supplies, inspection and verification of services and supplies
  • Review and approval of purchasing documents containing data describing the services and supplies ordered
  • Maintaining records for the evaluation of suppliers of critical consumables, supplies and services, which affect the quality of laboratory outputs.

4.13: Control of Records

  • Establishing and maintaining procedures for identification, collection, indexing, access, filing, storage and disposal of quality and technical records.
  • Providing procedures to protect and back-up records stored electronically and to prevent unauthorized access.

4.14: Internal Audits

  • Having a predetermined schedule and procedure for conducting internal audits of its activities and that addresses all elements that verify its compliance of its established management system and ISO/IEC 17025
  • Completing and recording corrective actions arising from internal audits in a timely manner, follow-up activities of implementation and verification of effectiveness of corrective actions taken.

5.2: Personnel

  • Laboratory management not ensuring the competence and qualifications of all personnel who operate specific equipment, perform tests, evaluate test results and sign test reports. Lack of personnel undergoing training and providing appropriate supervision
  • Providing a training program policies and procedures for an effective training program that is appropriate; identification and review of training needs and the program’s effectiveness to demonstrate competence.
  • Lack of maintaining records of training actions taken, current job descriptions for managerial, technical and key support personnel involved in testing

5.4: Test and Calibration Methods and Method Validation

  • Utilization of appropriate laboratory methods and procedures for all testing within the labs scope; including sampling, handling, transport, storage and preparation of items being tested, and where appropriate, a procedure for an estimation of the measurement of uncertainty and statistical techniques for analysis
  • Up-to-date instructions on the use and operation of all relevant equipment, and on the handling and preparation of items for testing
  • Introduction laboratory-developed and non-standard methods and developing procedures prior to implementation.
  • Validating non-standard methods in accordance with the standard
  • Not completing appropriate checks in a systematic manner for calculations and data transfers

5.6: Measurement Traceability

  • Ensuring that equipment used has the associated measurement uncertainty needed for traceability of measurements to SI units or certified reference materials and completing intermediate checks needed according to a defined procedure and schedules.
  • Not having procedures for safe handling, transport, storage and use of reference standards and materials that prevent contamination or deterioration of its integrity.

5.10: Reporting the Results

  • Test reports not meeting the standard requirements, statements of compliance with accounting for uncertainty, not providing evidence for measurement traceability, inaccurately amending reports.

SOP-3: Use of the Logo

  • Inappropriate use of PJLA’s logo on the laboratories test reports and/or website.
  • Using the incorrect logo for the testing laboratory or using the logo without prior approval from PJLA.
currencies around the world

The Global Price of Cannabis

By Marguerite Arnold, Marguerite Arnold
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currencies around the world

Cannabis pricing, globally, is a topic that is going to remain heated if not highly fluid for some time to come. Why? Government regulation (or lack thereof), compliance and even transport along with different models for commerce and consumption are creating an odd and absolutely uneven map of commodity pricing. We live in a world where accurate information is hard to come by. Even from ostensibly “official” sources that track operational markets. Black or legit.

It may sound complex today but it used to be a lot harder. As of just 2014, the UN’s Office of Drug Control listed the price of a gram of (black market) cannabis in Lichtenstein at $1,020 (as reported by a bemused Business Insider). While this could have been a simple matter of misunderstanding that Europeans frequently use commas rather than periods as decimal points in numbers, the fact that this was later corrected to $10.13 suggests human error in transcription rather than reporting. And the world has certainly changed since then.

Yet with no international legal marketplace or even platform yet in existence to track the global price of legal cannabis in different jurisdictions, this is the kind of issue that faces not only those in the industry but those trying to analyze it.

That said, there are beginning to be data points for those who are interested and those who must have this information for professional reasons. Here is a break-down of regional (legal) prices, per gram from a selection of sources generally considered fairly accurate. This is also made a bit more difficult by the difference in measurement systems and currency fluctuations. For ease of reference, these figures are in grams and U.S. dollars. An ounce is about 28 grams.currencies around the world

Medical grade cannabis also means different things in different markets. Outside the U.S., in Canada and the EU in particular, medical grade cannabis must meet a certification process that adds to the cost of production considerably. Certainly in comparison with outdoor grows. It is still, for the most part, imported, from either Canada or Holland, although look for that to start changing this year as domestic cultivation in multiple countries finally gets seriously underway.

The U.S.

Pricing really depends on where you are. It is also dropping fairly dramatically in established markets. The most recent example of this is Oregon – which has seen its higher-than-normal state retail market begin to normalize with California, Washington and Colorado. This is the price of establishing regulatory schemes on a non-federal level. That said, the competition is so extreme at the moment that Oregon, in particular, is a buyer’s market, with recently reported prices as low as $1 and change for a gram.

Retail pricing, in particular, will remain all over the place on a national level, especially given the amount of local competition between dispensaries underway. On average, however, medical grade-ish cannabis runs between $6-30 a gram, retail.

According to the website Cannabis Benchmarks, which tracks U.S. wholesale prices, the domestic spot index of wholesale cannabis was at $1,292 per pound at the end of January. Or about $5 per gram.The theory that the legit market has to price the black market out of existence is unpopular with those who want to collect more taxes from rec sales.

Nationally, at the moment, uncertainty over how the new post-Cole Memo world will play out, plus oversupply in certain markets, is creating strange pricing. Note to consumers, particularly in recreational markets: There are deals to be had.

Canada

This market is interesting for several reasons. The first is that several of the regional governments are considering establishing a Canadian $10 per gram price for the recreational market. Medical grade runs about $8 at the moment in local currency. That means, with a 20% differential in current f/x rates, a recreational gram will be set at USD $8 and a medical gram at about $6. That said, the theory that the legit market has to price the black market out of existence is unpopular with those who want to collect more taxes from rec sales.

Theories abound about the future of recreational pricing, but for the moment, a great deal of supply and new producers will keep prices low at least through 2019. After that? It is impossible to even guess. At that point, Canadian producers will still be supplying at least German medical patients with some of their imported bud. Regardless, the country will continue to play an important role in global pricing – even if it is to set a recreational and medical standard that plays out in markets already from the EU to Australia.

Israel

Like Canada’s market, although for different reasons, the Israeli official price on legal cannabis is absolutely constant. It is set by government policy. Those who have the drug legally, in other words with a doctor’s prescription, pay about $100 for a month’s supply. That amount on average is about 28 grams. That means that a medical gram in Israel will set you back about $3.50 per. U.S. not Canadian.

Europe

Price deltas here are the most impacted by changing national laws, standards and medical legalization. There are only two semi-legitimate recreational markets at the moment that include THC. Those are Holland and Spain. In Holland, via the coffee shops, the low-end of passable bud starts at between $12-15 per gram and goes up to about $30 for the really exotic breeds. This being Holland, they exist and are obtainable. In Spain, add the cost of joining a social club (about $50), but in general, the cost of a gram is about $10.Price deltas here are the most impacted by changing national laws, standards and medical legalization.

Medical markets in places like Germany are still skewed by integration of the drug into the country’s healthcare system and the fact that it is still all imported. The horror stories are real here. Patients must pay out-of-pocket right now for cannabis flower that is also being pre-ground by local apothekes for an additional price per gram that is eye-wincingly high. However, once the price and supply normalize, look for a medical standard here of about $10 for a month’s supply. That will be about 28 grams too.

Germany, in other words, will eventually be one of the cheapest markets for patients after reimbursement by insurance. That shapes up to be about $0.50 per gram at point of sale. It could be far less for those who are able to obtain authorization for higher amounts up to five ounces per month. The flat fee stays the same. Do the math. That works out to some pretty cheap (high grade) medical relief.

Black market cannabis and hash, which is also far more common in Europe than the U.S. at least, is fairly widely available for between $12 and $20 a gram.

The rise of cannabis production in Eastern Europe and the Baltics (which is also still largely pending and based on ongoing government talks and emerging distribution and cultivation agreements) will also dramatically drive down the cost of legal cannabis in the EU within the next several years. Production in this part of the world, along with Greece, may well also source rec markets all over the continent once that happens.

Africa & Central and South America

While the African cannabis trade has yet to break out – even in the media much of yet, there is definitely something green growing in several African countries including South Africa and Ethiopia. That trade unlike most of what is going on in South America with the possible exception of Uruguay is already looking for export opportunities globally. With African cannabis going for less than a buck a gram in most places (as in about a fifth of even that), look for certified African medical cannabis in select Western markets where price is going to be a major issue. Think medical standards. On the South American front, prices are equally low. However, remember that these are not regulated markets yet. And domestic government standards, starting with GMP and both indoor and outdoor grow requirements are basically non-existent. Growers who want to export to higher regulated markets are planning accordingly.

Assorted Outliers

It goes without saying that in places where cannabis is both illegal and carries the death penalty or other harsh penal retaliation, that the price is not only much higher, but the source is black market. In the UAE for example, a gram will set you back well over $100.