Tag Archives: Testing

Cannabis-Specific Certified Reference Materials

By Aaron G. Biros, Don Shelly
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A certified reference material (CRM) is generally recognized as providing the highest level of traceability and accuracy to a measurement. A CRM designed specifically for cannabis testing and tailored to state-specific testing regulations could help laboratories better ensure the safety of their products.

The fact that a certificate accompanies a reference material does not qualify it as a CRM. The reference material must be produced in accordance with ISO Guide 34 specifications by an accredited manufacturer. Adam Ross, key account manager and organic specialist at LGC Standards, says accreditation is a big part of bringing legitimacy to cannabis testing. “For a laboratory to receive an ISO 17025 accreditation, they must purchase their RMs from an ISO 17025 manufacturer. The best option is to purchase an ISO Guide 34 manufactured CRM,” says Ross. “It is particularly important for testing requirements, such as potency, pesticides, etc., where quantitation is expected, to use properly certified quantitative reference materials.” LGC Standards, a 175-year-old company, is one of those manufacturers that invested the time and money to achieve ISO Guide 34 accreditation and offers a spectrum of CRMs for cannabis testing.

Adam Ross, LGC Standards
Adam Ross, LGC Standards

The major advantage to using a proper CRM is an increased level of credibility. Auditors recognize the value of using a CRM which can add to the integrity of the results produced. The regular use of certified reference standards along with proper training, methodology and instrumentation, will facilitate a result that has the least amount of uncertainty and is more defendable. “The regular use of certified reference standards will help ensure products that go to market are safe to consume,” says Ross.

With regard to potency analyses, Ross has some key insights to help a laboratory better utilize CRMs. “My advice? Don’t mix the cannabinoids; labs analyzing by GC/FID have discovered that some of the cannabinoids will co-elute. Also, they have a short shelf life when mixed together,” says Ross. “Cannabinoid analysts should use GC/MS or LC/MS for their analysis or analyze the cannabinoids individually,” says Ross.

rsz_cannabis_product_photo_lgc-1So what happens if a cannabis lab uses non-certified reference materials? Labs might save money in the short term. CRMs are slightly more expensive than a non-certified reference material, but will increase the defensibility of a lab’s data. Using a reference material created in-house or from a non-accredited vendor can lead to less-than-accurate results. A non-certified reference material has a greater chance of being made incorrectly. The publication of incorrect data damages the credibility of the testing lab and could lead to legal action against the lab from damaged parties.

One of the major challenges for the cannabis testing industry is the variation in state-to-state regulations. Ross says that Oregon’s regulations are pretty comprehensive and that other states should look to the Oregon Environmental Laboratory Accreditation Program (ORELAP) for guidance. According to Ross, ORELAP would like to see higher quality standards with legitimate traceability. Utilizing CRMs the correct way will help laboratories achieve greater accuracy.

Here are some tips for using CRMs appropriately:

  • Always bring your standards to room temperature before making a dilution.
  • Matrix matched calibration standards provide more accurate quantitation. Prepare standards in the solvent from extracted blank matrices.
  • Always bracket your analytical runs with continuing calibration verification standards. Proving that your instrument remained calibrated during the run gives your data more credibility.

Analytical chemists purchase CRMs for three primary uses in the testing lab:

  • To calibrate the instrument that will be used to perform the testing
  • To confirm the instruments continuing calibration throughout the analytical process
  • For analytical quality control or “spikes”

Typically, labs will spike known concentrations of the analytes of interest into a control sample and regular samples with the intent of testing analytical efficiency. Recoveries of analytes from the spiked control sample tell the chemist how well the analytical method is working. The spiked samples (matrix spikes) demonstrate to what extent the sample matrix (the consumable being tested) is influencing the results of the analytical procedure.

CRMs could be described as the nexus between cannabis testing results, the human element and the instrumentation used in an analysis. By using a cannabis-specific CRM, the cannabis testing community can demonstrate tangible improvements in accuracy and legitimacy.

From The Lab

QuEChERS 101

By Danielle Mackowsky
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Sample preparation experts and analytical chemists are quick to suggest QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) to cannabis laboratories that are analyzing both flower and edible material for pesticides, mycotoxins and cannabinoid content. Besides having a quirky name, just what makes QuEChERS a good extraction technique for the complicated matrices of cannabis products? By understanding the chemistry behind the extraction and the methodology’s history, cannabis laboratories can better implement the technology and educate their workforce.

QuEChERS salt blends can be packed into mylar pouches for use with any type of centrifuge tubes
QuEChERS salt blends can be packed into mylar pouches for use with any type of centrifuge tubes

In 2003, a time when only eight states had legalized the use of medical cannabis, a group of four researchers published an article in the Journal of AOAC International that made quite the impact in the residue monitoring industry. Titled Fast and Easy Multiresidue Method Employing Acetonitrile Extraction/Partitioning and “Dispersive Solid-Phase Extraction” for the Determination of Pesticide Residues in Produce, Drs. Michael Anastassiades, Steven Lehotay, Darinka Štajnbaher and Frank Schenck demonstrate how hundreds of pesticides could be extracted from a variety of produce samples through the use of two sequential steps: an initial phase partitioning followed by an additional matrix clean up. In the paper’s conclusion, the term QuEChERS was officially coined. In the fourteen years that have followed, this article has been cited over 2800 times. Subsequent research publications have demonstrated its use in matrices beyond food products such as biological fluids, soil and dietary supplements for a plethora of analytes including phthalates, pharmaceutical compounds and most recently cannabis.

QuEChERS salts can come prepacked into centrifuge tubes
QuEChERS salts can come prepacked into centrifuge tubes

The original QuEChERS extraction method utilized a salt blend of 4 g of magnesium sulfate and 1 g of sodium chloride. A starting sample volume of 10 g and 10 mL of acetonitrile (ACN) were combined with the above-mentioned salt blend in a centrifuge tube. The second step, dispersive solid phase extraction (dSPE) cleanup, included 150 mg of magnesium sulfate and 25 mg of primary secondary amine (PSA). Subsequent extraction techniques, now known as AOAC and European QuEChERS, suggested the use of buffered salts in order to protect any base sensitive analytes that may be critical to one’s analysis. Though the pH of the extraction solvent may differ, all three methods agree that ACN should be used as the starting organic phase. ACN is capable of extracting the broadest range of analytes and is compatible with both LC-MS/MS and GC-MS systems. While ethyl acetate has also been suggested as a starting solvent, it is incompatible with LC-MS/MS and extracts a larger amount of undesirable matrix components in the final aliquot.

All laboratories, including cannabis and food safety settings, are constantly looking for ways to decrease their overhead costs, batch out the most samples possible per day, and keep their employees trained and safe. It is not a stretch to say that QuEChERS revolutionized the analytical industry and made the above goals tangible achievements. In the original publication, Anastassiades et al. established that recoveries of over 85% for pesticides residues were possible at a cost as low as $1 per ten grams of sample. Within forty minutes, up to twelve samples were fully extracted and ready to be analyzed by GC-MS, without the purchase of any specialized equipment. Most importantly, no halogenated solvents were necessary, making this an environmentally conscious concept. Due to the nature of the cannabis industry, laboratories in this field are able to decrease overall solvent usage by a greater amount than what was demonstrated in 2003. The recommended starting sample for cannabis laboratories is only one gram of flower, or a tenth of the starting volume that is commonly utilized in the food safety industry. This reduction in sample volume then leads to a reduction in acetonitrile usage and thus QuEChERS is a very green extraction methodology.

The complexity of the cannabis matrix can cause great extraction difficulties if proper techniques are not used
The complexity of the cannabis matrix can cause great extraction difficulties if proper techniques are not used

As with any analytical method, QuEChERS is not perfect or ideal for every laboratory setting. Challenges remain in the cannabis industry where the polarity of individual pesticides monitored in some states precludes them from being amenable to the QuEChERS approach. For cannabis laboratories looking to improve their pesticide recoveries, decrease their solvent usage and not invest their resources into additional bench top equipment, QuEChERS is an excellent technique to adopt. The commercialization of salt blends specific for cannabis flowers and edibles takes the guesswork out of which products to use. The growth of cannabis technical groups within established analytical organizations has allowed for better communication among scientists when it comes to best practices for this complicated matrix. Overall, it is definitely worth implementing the QuEChERS technique in one’s cannabis laboratory in order to streamline productivity without sacrificing your results.

The Practical Chemist

Pesticide Analysis in Cannabis and Related Products: Part 3

By Julie Kowalski
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As mentioned in Part 1, pesticides residue analysis is very challenging especially considering the complexity of cannabis and the variety of flower, concentrates and infused products. In addition, pesticides are tested at low levels typically at parts-per-billion (ppb). For example, the food safety industry often uses 10 ppb as a benchmark limit of quantification. To put that in perspective, current pesticides limits in cannabis range from 10 ppb default (Massachusetts Regulatory Limit) to a more typical range of 100 ppb to 2 ppm in other states. Current testing is also complicated by evolving regulations.

Despite these challenges, adaptation of methods used by the food safety industry have proved successful for testing pesticides in cannabis. These methods typically rely on mass spectrometric detection paired with sample preparation methods to render the sample clean enough to yield quality data.

Pesticide Analysis Methods: Sample preparation and Analytical Technique Strategy

Generally, methods can be divided into two parts; sample preparation and analytical testing where both are critical to the success of pesticide residue testing and are inextricably linked. Reliance on mass spectrometric techniques like tandem mass spectrometry and high resolution accurate mass (HRAM) mass spectrometry is attributed to the substantial sensitivity and selectivity provided. The sensitivity and selectivity achievable by the detector largely dictates the sample preparation that will be required. The more sensitive and selective the detector, the less rigorous and resource intensive sample preparation can be.

Analytical technique: Gas and Liquid Chromatography Tandem Mass Spectrometry 

The workhorse approach for pesticide residue analysis involves using gas chromatography and liquid chromatography tandem mass spectrometry (MS/MS) in the ion transition mode. This ion transition mode, often referred to as multiple reaction monitoring (MRM) or selected reaction monitoring (SRM), adds the selectivity and sensitivity needed for trace level analysis. Essentially, a pesticide precursor ion is fragmented into product ions. The detector monitors the signal for a specified product ion known to have originated from the pesticide precursor ion. This allows the signal to be corrected, associated with the analyte and not with other matrix components in the sample. In addition, because only ions meeting the precursor/product ion requirements are passed to the detector with little noise, there is a benefit to the observed signal to noise ratio allowing better sensitivity than in other modes. Even though ion transitions are specific, there is the possibility a matrix interference that also demonstrates that same ion transition could result in a false positive. Multiple ion transitions for each analyte are monitored to determine an ion ratio. The ion ratio should remain consistent for a specific analyte and is used to add confidence to analyte identification.

The best choice for pesticide analysis between gas chromatography (GC) and liquid chromatography (LC) is often questioned. To perform comprehensive pesticide screening similar to the way the food safety market approaches this challenge requires both techniques. It is not uncommon for screening methods to test for several hundred pesticides that vary in physiochemical properties. It may be possible that with a smaller list of analytes, only one technique will be needed but often in order to reach the low limits for pesticide residues both GC and LC are required.

Modified QuEChERS extraction using 1.5 grams of cannabis flower. Courtesy of Julie Kowalski (Restek Corporation), Jeff Dahl (Shimadzu Scientific Instruments) and Derek Laine (Trace Analytics).
Modified QuEChERS extraction using 1.5 grams of cannabis flower. Courtesy of Julie Kowalski (Restek Corporation), Jeff Dahl (Shimadzu Scientific Instruments) and Derek Laine (Trace Analytics).

Analytical technique: Sample Preparation

Less extensive sample preparation is possible when combined with sensitive and selective detectors like MS/MS. One popular method is the QuEChERS approach. QuEChERS stands for Quick, Easy, Cheap, Effective, Rugged and Safe. It consists of a solvent extraction/salting out step followed by a cleanup using dispersive solid phase extraction. Originally designed for fruit and vegetable pesticide testing, QuEChERS has been modified and used for many other commodity types including cannabis. Although QuEChERS is a viable method, sometimes more cleanup is needed and this can be done with cartridge solid phase extraction. This cleanup functions differently and is more labor intensive, but results in a cleaner extract. A cleaner extract helps to secure quality data and is sometimes needed for difficult analyses.

Colorado Cannabis Lab Methods Updated for Microbial Testing

By Aaron G. Biros
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The Colorado Department of Public Health and Environment’s (CDPHE) Marijuana Laboratory Inspection Program issued a bulletin on January 30th regarding updates required for licensed cannabis testing labs. The updated method for microbial contaminant testing includes a longer incubation period in yeast and mold testing.BannerForEnf

“After careful consideration of emerging data regarding the use and effectiveness of 3M Total Yeast and Mold Rapid Petrifilms in marijuana, CDPHE has concluded that 48 hours is not a sufficient incubation period to obtain accurate results,” the letter states. “Based upon the review of this information, marijuana/marijuana products require 60-72 hours of incubation as per the manufacturer’s product instructions for human food products, animal feed and environmental products.” The letter says they determined it was necessary to increase the incubation period based on data submitted from several labs, along with a paper found in the Journal of Food Protection.

An incubator (Right) at TEQ Analytical Labs
An incubator (Right) at TEQ Analytical Labs

According to Alexandra Tudor, manager of the microbiology department at TEQ Analytical Labs (a cannabis testing lab in Aurora, CO), the update is absolutely necessary. “The incubation time extension requirement from CDPHE offers more reliable and robust data to clients by ruling out the possibility of a false yeast and mold result during analysis,” says Tudor.

Alexandra Tudor, microbiology department manager at TEQ Analytical Labs
Alexandra Tudor, microbiology department manager at TEQ Analytical Labs

“3M, the maker of Petrifilm, recommends an incubation time of 48-72 hours, but during TEQ’s method validation procedure, we learned that 48-hour incubation was not sufficient time to ensure accurate results. Although some laboratories in industry had been incubating for the minimum amount of time recommended by the manufacturer, the 48-hour incubation time does not provide a long enough window to ensure accurate detection of microbiological contaminants present in the sample.” Tudor says the update will help labs provide more confident results to clients, promoting public health sand safety.IMG_6386-2

As a result of the update in testing methodology, cultivators and infused product manufacturers in Colorado need to submit a batch test for yeast and mold. The point of requiring this batch test is to determine if the producer’s process validation is still effective, given the new yeast and mold testing method.

Green Man Cannabis Recalls Due to Pesticide Residue Detection

By Aaron G. Biros
2 Comments

Denver-based Green Man Cannabis last week voluntarily recalled batches of cannabis sold to both medical patients and recreational consumers. The recall comes after the discovery of off-label pesticides during inspections in both dry-flower cannabis and infused products.

Photo: Sheila Sund, Flickr
Photo: Sheila Sund, Flickr

According to the Denver Department of Environmental Health (DEH), the products have labels that list an OPC License number of 403-00738, 403-00361, or 403R-00201. The cannabis in question is not a specific batch, rather, “All plant material and derived products originating from these cultivation facilities are subject to the recall.” The DEH’s statement includes contact information for the company (email: recall@greenmancannabis.com) and the DEH Public Health Inspections Division (email: phicomments@denvergov.org or 720-913-1311).

The DEH statement does not mention which pesticides were detected or the levels at which they were detected. Christian Hagaseth, founder of Green Man Cannabis, says the chemical detected was Myclobutanil. “We had used Eagle 20 in the past, [the pesticide that contains Myclobutanil] but we stopped using it as soon as it was banned,” says Hagaseth. “The DEH found the residues in the growing environment so we immediately performed a voluntary recall.” Green Man has three cultivation facilities, one of which they suspect is contaminated from pesticides sprayed a few years ago.

Christian Hageseth, founder of Green Man Cannabis
Christian Hageseth, founder of Green Man Cannabis

As far as corrective actions being taken, Hagaseth says they are doing a thorough cleaning and sanitation in two of their grows and a complete remediation plan in the suspected contaminated grow. “This was a good learning experience- the key takeaway for us is we need to clean these environments more consistently,” says Hagaseth. “I am grateful that the system is working; public health and environmental safety are being looked after here.” Hagaseth says the facility in question was operating almost without interruption since 2009, but they adjusted and learned to implement preventative actions following the recall.

The DEH says there have been zero reports of illness related to the recall. “The possible health impact of consuming marijuana products with unapproved pesticide residues is unknown,” the statement reads. “Short and long-term health impacts may exist depending on the specific product, duration, frequency, level of exposure and route of exposure.” The DEH advises consumers that may be concerned to reach out to their physician.

The DEH performs routine inspections of cannabis infused product manufacturers and retail locations in Denver, as well as investigating complaints. “I am sorry that it happened to us, but I am happy the system is working and we are more than happy to comply,” says Hagaseth.

The Practical Chemist

Potency Analysis of Cannabis and Derivative Products: Part 2

By Rebecca Stevens
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As mentioned in Part 1, the physiological effects of cannabis are mediated by a group of structurally related organic compounds known as cannabinoids. The cannabinoids are biosynthetically produced by a growing cannabis plant and Figure 1 details the biosynthetic pathways leading to some of the most important cannabinoids in plant material.

Potency figure 1
Figure 1: The biosynthetic pathway of phytocannabinoid production in cannabis has been deeply studied through isotopic labeling experiments

The analytical measurement of cannabinoids is important to ensure the safety and quality of cannabis as well as its extracts and edible formulations. Total cannabinoid levels can vary significantly between different cultivars and batches, from about 5% up to 20% or more by dry weight. Information on cannabinoid profiles can be used to tailor cultivars for specific effects and allows end users to select an appropriate dose.

Routine Analysis vs. Cannabinomics 

Several structurally analogous groups of cannabinoids exist. In total, structures have been assigned for more than 70 unique phytocannabinoids as of 2005 and the burgeoning field of cannabinomics seeks to comprehensively measure these compounds.¹

Considering practical potency analysis, the vast majority of cannabinoid content is accounted for by 10-12 compounds. These include Δ9-tetrahydrocannabinol (THC), cannabidiol (CBD), cannabigerol (CBG), Δ9-tetrahydrocannabivarian (THCV), cannabidivarin (CBDV) and their respective carboxylic acid forms. The cannabinoids occur primarily as carboxylic acids in plant material. Decarboxylation occurs when heat is applied through smoking, vaporization or cooking thereby producing neutral cannabinoids which are more physiologically active.

Potency Analysis by HPLC and GC

Currently, HPLC and GC are the two most commonly used techniques for potency analysis. In the case of GC, the heat used to vaporize the injected sample causes decarboxylation of the native cannabinoid acids. Derivatization of the acids may help reduce decarboxylation but overall this adds another layer of complexity to the analysis² ³. HPLC is the method of choice for direct analysis of cannabinoid profiles and this technique will be discussed further.

A sample preparation method consisting of grinding/homogenization and alcohol extraction is commonly used for cannabis flower and extracts. It has been shown to provide good recovery and precision² ³. An aliquot of the resulting extract can then be diluted with an HPLC compatible solvent such as 25% water / 75% acetonitrile with 0.1% formic acid. The cannabinoids are not particularly water soluble and can precipitate if the aqueous percentage is too high.

To avoid peak distortion and shifting retention times the diluent and initial mobile phase composition should be reasonably well matched. Another approach is to make a smaller injection (1-2 µL) of a more dissimilar solvent. The addition of formic acid or ammonium formate buffer acidifies the mobile phase and keeps the cannabinoid acids protonated.

The protonated acids are neutral and thus well retained on a C18 type column, even at higher (~50% or greater) concentrations of organic solvent² ³.

Detection is most often done using UV absorbance. Two main types of UV detectors are available for HPLC, single wavelength and diode array. A diode array detector (DAD) measures absorbance across a range of wavelengths producing a spectrum at each point in a chromatogram while single wavelength detectors only monitor absorbance at a single user selected wavelength. The DAD is more expensive, but very useful for detecting coelutions and interferences.

References

  1. Chemical Constituents of Marijuana: The Complex Mixture of Natural Cannabinoids. Life Sciences, 78, (2005), pp. 539
  2. Development and Validation of a Reliable and Robust Method for the Analysis of Cannabinoids and Terpenes in Cannabis. Journal of AOAC International, 98, (2015), pp. 1503
  3. Innovative Development and Validation of an HPLC/DAD Method for the Qualitative and Quantitative Determination of Major Cannabinoids in Cannabis Plant Material. Journal of Chromatography B, 877, (2009), pp. 4115

Rebecca is an Applications Scientist at Restek Corporation and is eager to field any questions or comments on cannabis analysis, she can be reached by e-mail, rebecca.stevens@restek.com or by phone at 814-353-1300 (ext. 2154)

amandarigdon
The Nerd Perspective

Pesticide Detection in Cannabis: Lab Challenges and Why Less Isn’t Always More

By Amanda Rigdon
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amandarigdon

Almost as soon as cannabis became recreationally legal, the public started to ask questions about the safety of products being offered by dispensaries – especially in terms of pesticide contamination. As we can see from the multiple recalls of product there is a big problem with pesticides in cannabis that could pose a danger to consumers. While The Nerd Perspective is grounded firmly in science and fact, the purpose of this column is to share my insights into the cannabis industry based on my years of experience with multiple regulated industries with the goal of helping the cannabis industry mature using lessons learned from other established markets. In this article, we’ll take a look at some unique challenges facing cannabis testing labs, what they’re doing to respond to the challenges, and how that can affect the cannabis industry as a whole.

Photo: Michelle Tribe, Flickr
Photo: Michelle Tribe, Flickr

The Big Challenge

Over the past several years, laboratories have quickly ‘grown up’ in terms of technology and expertise, improving their methods for pesticide detection to improve data quality and lower detection limits, which ultimately ensures a safer product by improving identification of contaminated product. But even though cannabis laboratories are maturing, they’re maturing in an environment far different than labs from regulated industry, like food laboratories. Food safety testing laboratories have been governmentally regulated and funded from almost the very beginning, allowing them some financial breathing room to set up their operation, and ensuring they won’t be penalized for failing samples. In contrast, testing fees for cannabis labs are paid for by growers and producers – many of whom are just starting their own business and short of cash. This creates fierce competition between cannabis laboratories in terms of testing cost and turnaround time. One similarity that the cannabis industry shares with the food industry is consumer and regulatory demand for safe product. This demand requires laboratories to invest in instrumentation and personnel to ensure generation of quality data. In short, the two major demands placed on cannabis laboratories are low cost and scientific excellence. As a chemist with years of experience, scientific excellence isn’t cheap, thus cannabis laboratories are stuck between a rock and a hard place and are feeling the squeeze.

Responding to the Challenge

One way for high-quality laboratories to win business is to tout their investment in technology and the sophistication of their methods; they’re selling their science, a practice I stand behind completely. However, due to the fierce competition between labs, some laboratories have oversold their science by using terms like ‘lethal’ or ‘toxic’ juxtaposed with vague statements regarding the discovery of pesticides in cannabis using the highly technical methods that they offer. This juxtaposition can then be reinforced by overstating the importance of ultra-low detection levels outside of any regulatory context. For example, a claim stating that detecting pesticides at the parts per trillion level (ppt) will better ensure consumer safety than methods run by other labs that only detect pesticides at concentrations at parts per billion (ppb) concentrations is a potentially dangerous claim in that it could cause future problems for the cannabis industry as a whole. In short, while accurately identifying contaminated samples versus clean samples is indeed a good thing, sometimes less isn’t more, bringing us to the second half of the title of this article.

Less isn’t always more…

Spiral Galaxy Milky Way
The Milky Way

In my last article, I illustrated the concept of the trace concentrations laboratories detect, finishing up with putting the concept of ppb into perspective. I wasn’t even going to try to illustrate parts per trillion. Parts per trillion is one thousand times less concentrated than parts per billion. To put ppt into perspective, we can’t work with water like I did in my previous article; we have to channel Neil deGrasse Tyson.

The Milky Way galaxy contains about 100 billion stars, and our sun is one of them. Our lonely sun, in the vastness of our galaxy, where light itself takes 100,000 years to traverse, represents a concentration of 10 ppt. On the surface, detecting galactically-low levels of contaminants sounds wonderful. Pesticides are indeed lethal chemicals, and their byproducts are often lethal or carcinogenic as well. From the consumer perspective, we want everything we put in our bodies free of harmful chemicals. Looking at consumer products from The Nerd Perspective, however, the previous sentence changes quite a bit. To be clear, nobody – nerds included – wants food or medicine that will poison them. But let’s explore the gap between ‘poison’ and ‘reality’, and why that gap matters.

FDAIn reality, according to a study conducted by the FDA in 2011, roughly 37.5% of the food we consume every day – including meat, fish, and grains – is contaminated with pesticides. Is that a good thing? No, of course it isn’t. It’s not ideal to put anything into our bodies that has been contaminated with the byproducts of human habitation. However, the FDA, EPA, and other governmental agencies have worked for decades on toxicological, ecological, and environmental studies devoted to determining what levels of these toxic chemicals actually have the potential to cause harm to humans. Rather than discuss whether or not any level is acceptable, let’s take it on principle that we won’t drop over dead from a lethal dose of pesticides after eating a salad and instead take a look at the levels the FDA deem ‘acceptable’ for food products. In their 2011 study, the FDA states that “Tolerance levels generally range from 0.1 to 50 parts per million (ppm). Residues present at 0.01 ppm and above are usually measurable; however, for individual pesticides, this limit may range from 0.005 to 1 ppm.” Putting those terms into parts per trillion means that most tolerable levels range from 100,000 to 50,000,000 ppt and the lower limit of ‘usually measurable’ is 10,000 ppt. For the food we eat and feed to our children, levels in parts per trillion are not even discussed because they’re not relevant.

green apple with slice isolated on the white background.

A specific example of this is arsenic. Everyone knows arsenic is very toxic. However, trace levels of arsenic naturally occur in the environment, and until 2004, arsenic was widely used to protect pressure-treated wood from termite damage. Because of the use of arsenic on wood and other arsenic containing pesticides, much of our soil and water now contains some arsenic, which ends up in apples and other produce. These apples get turned into juice, which is freely given to toddlers everywhere. Why, then, has there not an infant mortality catastrophe? Because even though the arsenic was there (and still is), it wasn’t present at levels that were harmful. In 2013, the FDA published draft guidance stating that the permissible level of arsenic in apple juice was 10 parts per billion (ppb) – 10,000 parts per trillion. None of us would think twice about offering apple juice to our child, and we don’t have to…because the dose makes the poison.

How Does This Relate to the Cannabis Industry?

The concept of permissible exposure levels (a.k.a. maximum residue limits) is an important concept that’s understood by laboratories, but is not always considered by the public and the regulators tasked with ensuring cannabis consumer safety. As scientists, it is our job not to misrepresent the impact of our methods or the danger of cannabis contaminants. We cannot understate the danger of these toxins, nor should we overstate their danger. In overstating the danger of these toxins, we indirectly pressure regulators to establish ridiculously low limits for contaminants. Lower limits always require the use of newer testing technologies, higher levels of technical expertise, and more complicated methods. All of this translates to increased testing costs – costs that are then passed on to growers, producers, and consumers. I don’t envy the regulators in the cannabis industry. Like the labs in the cannabis industry, they’re also stuck between a rock and a hard place: stuck between consumers demanding a safe product and producers demanding low-cost testing. As scientists, let’s help them out by focusing our discussion on the real consumer safety issues that are present in this market.

*average of domestic food (39.5% contaminated) and imported food (35.5% contaminated)

OHA Addresses Oregon Growing Pains, Changes Testing Rules

By Aaron G. Biros
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Last week, the Oregon Health Authority (OHA) published a bulletin, outlining new temporary testing requirements effective immediately until May 30th of next year. The changes to the rules come in the wake of product shortages, higher prices and even some claims of cultivators reverting back to the black market to stay afloat.img_6245

According to the bulletin, these temporary regulations are meant to still protect public health and safety, but are “aimed at lowering the testing burden for producers and processors based on concerns and input from the marijuana industry.” The temporary rules, applying to both medical and retail products, are a Band-Aid fix while the OHA works on a permanent solution to the testing backlog.

Here are some key takeaways from the rule changes:

Labeling

  • THC and CBD amounts on the label must be the value calculated by a laboratory, plus or minus 5%.

Batch testing

  • A harvest lot can include more than one strain.
  • Cannabis harvested within a 48-hour period, using the same growing and curing processes can be included in one harvest lot.
  • Edibles processors can include up to 1000 units of product in a batch for testing.
  • The size of a process lot submitted for testing for concentrates, extracts or other non-edible products will be the maximum size for future sampling and testing.

    Oregon Marijuana Universal Symbol for Printing
    Oregon Marijuana Universal Symbol for Printing

Sampling

  • Different batches of the same strain can be combined for testing potency.
  • Samples can be combined from a number of batches in a harvest lot for pesticide testing if the weight of all the batches doesn’t exceed ten pounds. This also means that if that combined sample fails a pesticide test, all of the batches fail the test and need to be disposed.

Solvent testing

  • Butanol, Propanol and Ethanol are no longer on the solvent list.

Potency testing

  • The maximum concentration limit for THC and CBD testing can have up to a 5% variance.

Control Study

  • Process validation is replaced by one control study.
  • After OHA has certified a control study, it is valid for a year unless there is an SOP or ingredient change.
  • During the control study, sample increments are tested separately for homogeneity across batches, but when the control study is certified, sample increments can be combined.

Failing a test

  • Test reports must clearly show if a test fails or passes.
  • Producers can request a reanalysis after a failed test no later than a week after receiving failed test results and that reanalysis must happen within 30 days.
Gov. Kate Brown Photo: Oregon Dept. of Transportation
Gov. Kate Brown
Photo: Oregon Dept. of Transportation

The office of Gov. Kate Brown along with the OHA, Oregon Department of Agriculture (ODA) and Oregon Liquor Control Commission (OLCC) issued a letter in late November, serving as a reminder of the regulations regarding pesticide use and testing. It says in bold that it is illegal to use any pesticide not on the ODA’s cannabis and pesticide guide list. The letter states that failed pesticide tests are referred to ODA for investigation, which means producers that fail those tests could face punitive measures such as fines.

Photo: Michelle Tribe, Flickr
Photo: Michelle Tribe, Flickr

The letter also clarifies a major part of the pesticide rules involving the action level, or the measured amount of pesticides in a product that the OHA deems potentially dangerous. “Despite cannabis producers receiving test results below OHA pesticide action levels for cannabis (set in OHA rule), producers may still be in violation of the Oregon Pesticide Control Act if any levels of illegal pesticides are detected.” This is crucial information for producers who might have phased out use of pesticides in the past or might have began operations in a facility where pesticides were used previously. A laboratory detecting even a trace amount in the parts-per-billion range of banned pesticides, like Myclobutanil, would mean the producer is in violation of the Pesticide Control Act and could face thousands of dollars in fines. The approved pesticides on the list are generally intended for food products, exempt from a tolerance and are considered low risk.

As regulators work to accredit more laboratories and flesh out issues with the industry, Oregon’s cannabis market enters a period of marked uncertainty.

First Nevada Cannabis Lab Receives ISO 17025 Accreditation.

By Aaron G. Biros
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On December 7th, 374 Labs received ISO 17025 accreditation, becoming the first in Nevada to do so. The laboratory, based in Sparks, Nevada, is state-certified and now the only ISO 17025 accredited lab in the state, according to a press release. The laboratory is a member in both the Association of Commercial Cannabis Laboratories (ACCL) and the Nevada Cannabis Laboratory Association (NVCLA).

Managing Partner Alec Garcia at the LCMS/MS
Managing Partner Alec Garcia at the LCMS/MS

“As Nevada transitions into an adult-use cannabis market, it’s very important that the state’s cannabis testing laboratories are held to the highest standards – and ISO 17025 is a requirement of top testing laboratories in all industries from biotech to forensics in most major countries,” says Dr. Jeff Angermann, assistant professor in the University of Nevada, Reno’s School of Community Health Sciences.

Laboratory Technician Bevan Meade working on sample preparation.
Laboratory Technician Bevan Meade working on sample preparation.

According to the release, 374 Labs was a driving force behind Nevada’s round robin cannabis lab testing program. That program, administered by the Nevada Division of Public and Behavioral Health (DPBH) and the Nevada Department of Agriculture (NDA), sends cannabis samples to each state-certified cannabis lab for a full analysis, measuring the consistency in test results across labs. “In other states proficiency involves testing pre-prepared, purified samples and neglects the challenges of coaxing out delicate analytes from the complex array of compounds found in actual marijuana,” says Laboratory Director Jason Strull. “I commend the DPBH and NDA for facilitating such an advanced quality program.”

Also notable is the announcing of their partnership with Clean Green Certified, a third-party certification (based on USDA organic certification) for sustainable, organically based cannabis cultivation. “Nevada allows certain levels of pesticides like Myclobutanil on its certified marijuana, so we wanted a way for patients and consumers to able to distinguish marijuana that is grown using organic methods,” said Laboratory Director Jason Strull. According to Michael Seibert, managing member of 374 Labs, they have already started performing inspections for the third-party certification and the first facility inspected was Silver State Trading in Sparks, Nevada (certified for both production and cultivation).

Steep Hill, ACCL Find Pesticides in Over 50% of Cannabis Samples

By Aaron G. Biros
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On Election Day, voters in California passed Proposition 64, establishing a recreational cannabis market and regulatory environment. While the state won’t issue the first licenses under the new regulatory scheme until 2018, the medical cannabis industry is already well established.

Steep Hill Labs, Inc., based in Berkeley, California, found in October that 84.3% of samples submitted tested positive for pesticide residue, according to a press release. The announcement came before Election Day, but is particularly eye opening given the massive new market created overnight by Prop 64.rsz_steephill_lab_images_25_of_415_copy

Particularly concerning is their detection of Myclobutanil, which was found in more than 65% of samples submitted to the lab. According to the press release, when Myclobutanil is heated (i.e. smoked or vaporized), it is converted to Hydrogen Cyanide, which is extraordinarily toxic to humans and can be fatal in higher doses.

Reggie Gaudino, Ph.D., vice president of scientific operations and director of genetics at Steep Hill Laboratories. (photo credit: Preston Gannaway)
Reggie Gaudino, Ph.D. (photo credit: Preston Gannaway)

According to Reggie Gaudino, Ph.D., vice president of science, genetics and intellectual property at Steep Hill, their more recent study shows they detected pesticides in roughly 70% of the samples they received and 50% of those contained Myclobutanil. Gaudino says that up to a third of those samples would have failed under Oregon’s regulatory standards.

If a lab test were failed, it would contain pesticides at or higher than the required action level. Oregon’s action level, or the measured amount of pesticides in a product that the OHA deems potentially dangerous, for Myclobutanil is 0.2 parts-per-million (PPM). Steep Hill’s instrumentation has a method detection limit down to the parts-per-trillion (PPT) level, which is a more precise and smaller amount than Oregon’s action level.

“Those in the cannabis community who feel that all cannabis is safe are not correct given this data – smoking a joint of pesticide-contaminated cannabis could potentially expose the body to lethal chemicals,” says Jmichaele Keller, president and chief executive officer of Steep Hill. “As a community, we need to address this issue immediately and not wait until 2018.”

Potentially harmful pesticides, and specifically Myclobutanil, have been detected in Colorado and Washington’s recreational markets on a number of occasions, proving this is a widespread issue. Steep Hill’s release suggests that California regulators take a look at Oregon’s pesticide regulations for guidance when developing the regulatory framework.

What’s even more troubling is that not all laboratories have or had the capability of detecting pesticides at sufficiently low levels and because of this, other labs had significantly lower rates of pesticide detection, suggesting possible inconsistencies in testing methods, instrumentation, sample preparation or other variations. During a 30-day period in late September and early October, Steep Hill found, using publicly available data, or data from contracted testing, that other labs were only reporting between 3% and 21% pesticide detection.

Examination of cannabis prior to testing- credit Steep Hill Labs, Inc.
Examination of cannabis prior to testing- credit Steep Hill Labs, Inc.

It is important to note that those samples were not identical and there could be a great degree in variation on the quality of samples sent to different laboratories, so it is not an entirely accurate comparison. Steep Hill does however detect pesticides down to the parts-per-trillion level, whereas many common methods for detecting pesticides look at the parts-per-billion level.

Reggie Gaudino says the Association of Commercial Cannabis Laboratories (ACCL) is using this data to work with Steep Hill and a number of other labs to address these issues. “As a member of the ACCL, and after discussion with ACCL, we have agreed that all future discussion of this issue should not include laboratory names, as this is about educating the industry in general, and making sure all members of the ACCL are developing the best possible methods for detecting pesticides,” says Gaudino. “The ACCL has responded to this data, by inquiring on a larger, industry-wide basis, which represents a better picture of the issue, rather than only in California’s still-technically unregulated market.” The important message is this is a major issue that needs addressing urgently. “As such, the troubling issue remains, across the larger ACCL membership, there is still detection of pesticides in at least 50% of the cannabis being tested.”

ACCL logoAccording to Jeffrey Raber, Ph.D., president of the ACCL, the industry is experiencing a pesticide problem, but it is very difficult to quantify. “It is fair to say that around 50% of the cannabis being tested contains pesticides, but we really don’t know that exact number until a much more comprehensive statistical analysis is performed,” says Raber. “We agree this is a big problem and that it needs to be addressed, but we are not sure just how big of a problem it really is.” With so much variation in labs in a state where not everyone is required to test products, it is very difficult to pin down how consistent lab results are and how contaminated the cannabis really is. “If all of the labs had the same methodology, samples and shared statistical analyses for a real study then we can look at it closely but it seems we are a ways off from that. I can say confidently however that this is a pretty significant problem that needs addressing.”

Still, Steep Hill detecting pesticides in a majority of their samples and some labs finding as little as 3% should raise some eyebrows. “Unfortunately, our recent study discovered that 84.3% of the samples assessed by our triple quadrupole mass spectrometer contained pesticides,” says Keller. “As of today, this tainted product could be sold in most dispensaries throughout the state of California without any way of informing the patients about the risks of pesticide exposure.”

These findings could mean potentially enormous health risks for medical and recreational cannabis consumers alike, unless regulators, labs and growers take quick action to address the problem.