Tag Archives: laboratory

Soapbox

Hemp in the United States: An Opinion

By Dr. Anthony Macherone
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The Agriculture Improvement Act, also known as the Farm Bill, was signed into law in December 2018. A major provision in the law legalizes hemp as an industrial crop. In August of 2016, USDA, DEA, and FDA published a Statement of Principles in the Federal Register (FR 53365) that defined industrial hemp as any part or derivative (including seeds) of the plant Cannabis sativa L. with a dry weight concentration of tetrahydrocannabinols not greater than 0.3% (wt/wt).

USDA LogoGlobally, the hemp market was estimated at $3.9 billion in 2017 and the hemp seed segment is predicted to grow “at a CAGR of 17.1%” through 2025. Some of the markets affected by hemp production include nutraceuticals, food, textiles, construction materials, and personal care products. It is also anticipated that cannabidiol (a non-psychoactive cannabinoid extracted from hemp) production will grow to support the burgeoning recreational and medicinal cannabis markets in the U.S., Canada and other countries around the world.

In U.S. states and Canada where recreational or medicinal marijuana programs have been legalized, regulations have been defined to assure the safety and quality of the products sold to consumers. These regulations include analytical chemistry and biological assays to identify and quantify pesticides, mycotoxins, heavy metals, residual manufacturing solvents, terpenes, and microbial contaminates. With regards to hemp, the USDA recently released guidelines for testing of hemp. To date, the only required test from the Federal perspective is total ∆9-tetrahydrocannabinol (THC) content < 0.3% by weight. Total THC is essentially the sum of tetrahydrocannabinolic acid (THCA) and THC (Total THC = 0.877(THCA) + THC) but this may be eventually expanded to include all salts and isomers of cannabinols as noted above. Another complication: what constitutes “dry”? The CFR does not answer this.

Agilent Technologies has invested in the development and implementation of the analytical protocol, the services needed to support these assays, the required consumables, reagents, and supplies, and the training of sales and support personnel to comprehensively ensure compliance of hemp with USDA regulations.

Nevada Lab License Suspended Amid Potency Results Investigation

By Aaron G. Biros
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Back in September, Nevada officials announced a state-wide investigation into how products with high levels of yeast and mold were sold in dispensaries and alleged that labs could possibly be manipulating potency numbers on certificates of analysis. Then in late November, regulators suspended the license for Certified Ag Labs, a cannabis testing laboratory based in Sparks, Nevada.

Nevada regulators issued a press release alleging that products tested at Certified Ag Labs “may be labeled incorrectly and could contain a different level of THC than what is listed on product packaging.” Randy Gardner, a managing member at Certified Ag Labs told the Las Vegas Review-Journal that investigators showed up to his lab in October twice to collect samples for follow up tests.

On November 18, a state notice posted on the door of the lab read, “Registration and License Suspended,” according to the Las Vegas Review-Journal.

After that, Gardner fired back. In a statement sent out shortly after, Gardner said they were accused of lying about THC test results to the Department of Taxation (the agency that regulates cannabis in Nevada).

“The state’s decision to suspend and potentially revoke our license came without warning,” says Gardner’s statement. “This accusation is as baseless as it is appalling, as we have been completely transparent with the state at all times. We take this matter very seriously, and based on my over 30 years of laboratory experience we believe these allegations unconscionable at best.”

“The state came in for their audit then came back and suspended our license without us having a chance to further clarify or refute their findings,” the statement reads. “We hope the state appreciates that a business and its employees’ livelihoods and reputations are at stake. We are pursuing our options and all legal and equitable redress will be on the table.”

The Department of Taxation, which isn’t releasing any more information currently, says they found “inaccurate and misleading” potency test results, once they tested the samples collected from Certified Ag Labs.

This isn’t the first time Nevada regulators have suspended lab testing licenses. When Nevada legalized adult use sales and the market became operational back in 2017, the state suspended a lab’s license in September of that year. Then in late 2017, Certified Ag Labs and another lab had their licenses suspended for “not following proper lab procedures and good laboratory practices,” according to Stephanie Klapstein, spokeswoman for the Department of Taxation. Those licenses were reinstated in January of 2018.

How to Protect Your Business from the Emerging Vaping Crisis

By Tom BeLusko, Kelly McCann
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The year 2020 may become a pivotal year for cannabis operators and service providers, including increased access to financial services, and increased exposure to product liability lawsuits. On a positive note, if enacted, the Secure and Fair Enforcement Banking Act of 2019 (SAFE Banking Act) promises to enable cannabis businesses to gain access to financial services previously unavailable to them, including banking and insurance services. The House of Representatives passed the SAFE Banking Act of 2019 on September 25th, 2019. Skopos Labs, an automated predictive intelligence service, predicts there is a 52% chance of the SAFE Banking Act of 2019 becoming law. A recent discovery that vitamin E acetate is likely the culprit in the vaping-related illness epidemic may increase the exposure to costly litigation that cannabis businesses face.

An uptick in litigation like that currently affecting the vaping industry may soon affect cannabis businesses. More litigation affecting the vaping industry is due in large part to the growing number of lung injuries and deaths linked to vaping. As of November 13th, 2019, the CDC reported 2,172 cases of lung injury, and 42 deaths linked to vaping. The cases of lung injury and death have predictably resulted in an increase in litigation facing the vaping industry. Most of the plaintiffs in these cases allege they became addicted to vaping but at least two lawsuits go further. In one, a Connecticut man alleges that he suffered a massive, debilitating stroke as a result of vaping, while in another the parents of a teenage girl allege in a proposed class action suit that their daughter has suffered seizures linked to vaping. On November 14th, 2019, the CDC identified vitamin E acetate as a chemical of concern among people with vaping use associated lung injury. Vitamin E acetate is an additive commonly used as a cutting agent in vape cartridges. About 86% of individuals who have either vaping-related lung injuries, or died due to vaping had used a product containing THC.

The increase in perceived exposure cannabis businesses face has increased their interest in obtaining insurance, but unfortunately insurers are not always interested in insuring them. There are at least two reasons that getting insurance can be difficult for cannabis businesses: (1) insurance industry appetite for cannabis risk is very low due to its status under federal law and (2) express coverage exclusions or limitations of cannabis exposures from standard-form coverage are becoming more common. However, even if cannabis businesses are able to obtain insurance, their insurance may cover them for far less than they believe.

The product liability coverage (which is increasingly crucial for both growers and manufacturers given the mounting litigation facing the vaping industry) may cover far less than it at first appears. The interplay of exclusions and limited coverages in many cannabis-specific policies may leave a cannabis business uninsured.

It is vital now more than ever to ensure you are properly protected against loss.Crucial for cannabis businesses to appreciate is the distinction between “occurrence” and “claims-made” coverage triggers as it relates to both the premises on which cannabis businesses operate their business, and the products they sell.

Many cannabis businesses have an occurrence-based general liability insurance that might actually exclude: (1) product-liability risks; (2) any tobacco-related risks; and (3) any risk associated with governmental investigation or enforcement. These exclusions oftentimes concern cannabis businesses because there is a high likelihood one of these risks could manifest itself as an uninsured loss. Still, the costs of eliminating these exclusions in an occurrence-based general liability insurance policy is often large, assuming an insurer is willing to eliminate the exclusions on an occurrence basis at all. Therefore, cannabis businesses often pair their general liability insurance policy with a “claims-made” coverage trigger for products liability. Navigating the waters of managing the differences between “occurrence” and “claims-made” forms are best left to a qualified and experienced insurance professional.

Consult a local insurance professional that understands how to help your business become properly protected in what would be considered a tumultuous market for this burgeoning industry.

It is vital now more than ever to ensure you are properly protected against loss. As a first step, you must determine what your current insurance policy does and does not cover. After a loss, it is too late to change policies. Rely upon someone that knows the market of insuring this industry and has deep experience in managing both occurrence and claims-made policies.

Mark Your Calendars: The Cannabis Labs Virtual Conference Returns

By Cannabis Industry Journal Staff
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On January 15th, 2020, Cannabis Industry Journal is hosting the 3rd Annual Cannabis Labs Virtual Conference. From 11–4 pm ET, you’ll get access to five veterans of the cannabis industry discussing a wide range of cannabis testing issues. Hear from subject matter experts who will share their perspectives on regulations for cannabis and hemp testing, THC and CBD testing, laboratory management, moisture content and water activity and microbiological testing.

Speakers include:

  • Charles Deibel, President & CEO of Deibel Labs, Inc.
  • Dr. Brady Carter, Sr. Applications Scientist with Neutec
  • Aaron Hilyard, Microbiologist at DigiPath Labs
  • Heather Wade, President of Heather Wade Group, LLC
  • Heather Ebling, Senior Applications & Support Manager at Medicinal Genomics

Attendees will have the opportunity to ask speakers questions during the live Q&A session that follows each presentation. Five experts, five presentations, all on the same day and free to attend. Register now for this complimentary series of webinars. 

Cannabis Labs Virtual Conference

CannabisIndustryJournal.com is proud to present the 3rd Annual Cannabis Labs Virtual Conference. This complimentary collection of webinar presentations will help attendees better understand some of the more technical aspects of starting and operating a laboratory. We will take a deep dive into cannabis and hemp testing, THC and CBD testing, laboratory management, moisture content and water activity as well as an overview of regulations throughout the United States. Take a look at the presentations and speakers below for more information.

Attendees registering for this complimentary series of webinars will get access to five veterans of the cannabis lab testing industry, who are all available for Q&A after each presentation. In addition to getting the opportunity to chat with these subject matter experts on January 15th, a recording of the presentations will be made available to all who register.

Practical and educational information from experts in the cannabis lab testing industry, all on the same day and all from the comfort of your lab, home or office. Want real inside knowledge on the cannabis testing industry? Sign up today!

Steven Burton

Standardization: A Guide Through the Minefield

By Steven Burton
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Steven Burton

Now that cannabis edibles have been legalized nationally in Canada, many existing and aspiring license holders have been surprised to discover that they must comply with food safety regulations. This became crystal clear when Health Canada published their Good Production Practices Guide For Cannabis in August 2019.

With this development, it should be obvious to everyone that Good Manufacturing Practices (GMP) certifications are simply not enough.

Hazard Analysis and Critical Control Point (HACCP) based preventative control programs are now the absolute minimum and higher levels of certification (GFSI) should be on everyone’s wish list.

HACCP is a methodology that is all about identifying biological, chemical and physical hazards and determining how they will be controlled to mitigate the risk of injury to humans. Recently, bio-terrorism and food fraud hazards have been added to the list and it is a good idea to address quality hazards as well.

The process of developing a HACCP program involves identifying these hazards with respect to ingredients, materials, packaging, processes and cross-contamination points (explicitly required in Canada only). However, it is a specific ingredient hazard that I’d like to talk about here.

HACCPAs this market has emerged, I’ve met with many cannabis companies as the onerous levels of knowledge and effort required to build and maintain an effective HACCP program manually has dawned upon the industry. Many are looking for technological solutions to quickly solve this problem. During these discussions, a curious fact has emerged that set off the food safety alarm klaxons around here.

Most people alive today are too young to remember this but, with few exceptions, the standardization of ingredients is a relatively modern phenomenon. It used to be that the fat content of your milk varied from season to season and cow to cow. Over time, the food industry standardized so that, amazingly, you can now choose between milks with either 1% or 2% fat, a level of precision that would border on miraculous to someone born in the early 20th century.

The standardization of ingredients is important in terms of both quality and safety. Take alcohol for example. We know that a shot of spirits generally contains 40% alcohol. Different products may vary from this standard but, if I pour a shot of my favourite Bowmore No.1 single malt in Canada or Tasmania, this year or 10 years from now, I can expect a consistent effect from the 40% alcohol content of the quantity I’ve imbibed.

Imagine a world in which this was not the case, where one shot would be 40% but the next might be 80%. Things could get out of control quite easily at the 80% level so, to avoid this, distillers monitor and blend their product to ensure they achieve the 40% target, which is called the “standardization marker”.

With respect to cannabis, the obvious standardization marker is THC. During the manufacturing process, edibles manufacturers do not normally add cannabis flower directly into their products but instead add a THC concentrate produced during previous production steps. However, we’ve found that the wisdom of standardizing these concentrates has not yet dawned upon many in the industry, which is alarming at best and dangerous at worst.

The reason for this is that, since cannabis is inherently a heterogeneous plant, one cannot precisely achieve a particular marker value so the outcome of the concentration process is variable. The food industry long ago overcame this problem by blending or diluting to achieve a consistent marker concentration, but the cannabis industry has not yet adopted this advance.

The cannabis edibles industry is still immature and it will take time to bring all the necessary risk mitigation processes into place but one excellent place to start is to seriously consider standardizing concentrates to a THC marker.Instead, manufacturers simply keep track of the strength of each batch of concentrate and then adjust the quantity added to their recipes to achieve the desired THC content. This seems logical on the surface but presents a serious risk from the HACCP perspective, namely a chemical hazard, “Excessive psychoactive compound concentrations due to human error at levels that may be injurious to human health”.

The reality is that workers make mistakes, which is why it is imperative to mitigate the risk of human error insomuch as possible. One of the best ways to do this is to standardize to avoid the scenario where a worker, faced with a row of identical containers that are differentiated only by a tiny bit of text, accidentally grabs the wrong bottle. The error isn’t caught until the product has been shipped, consumed, and reports of hospital visits start coming in after the authorities trace the problem back to you. You must bear the costs of the recall, your reputation has been decimated and your company is floundering on the financial rocks.

US-based Drip More, LP recently found this out the hard way after consumers complained that their product tasted bad, bitter and/or harsh. An investigation determined that excessive nicotine content was the source of the problem and a voluntary recall was initiated. Affected product that had already been sold in 26 states. The costs of this recall have not been tallied but they will be staggering.

The cannabis edibles industry is still immature and it will take time to bring all the necessary risk mitigation processes into place but one excellent place to start is to seriously consider standardizing concentrates to a THC marker. This strategy is cheap, easy and you’ll never be sorry.

Soapbox

3 Food Safety Precautions for Edibles

By Cindy Rice
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You’ve survived seasons of cannabis cultivations, bringing in quality plants in spite of mold, mites, drought and other challenges that had to be conquered. Extraction methods are sometimes challenging, but you are proud to have a cannabinoid extract that can be added into your own products for sale. Edibles are just waiting to be infused with the cannabinoids, for consumers demanding brownies, gummies, tinctures and almost any food and beverage imaginable. You’ve been through the fire, and now the rest is easy peasy, right?

Food processing and sanitation
Avoiding cross contamination should be a priority for edibles manufacturing

Actually, producing edibles may not be so seamless as you think. Just as in the rest of the food industry, food safety practices have to be considered when you’re producing edibles for public consumption, regardless of the THC, CBD, terpene or cannabinoid profile. Once you’ve acquired the extract (a “food grade ingredient”) containing the active compounds, there are three types of hazards that could still contribute to foodborne illness from your final product if you’re not careful- Biological, Chemical and Physical.

Biological hazards include pathogenic bacteria, viruses, mold, mildew (and the toxins that they can produce) that can come in ingredients naturally or contaminate foods from an outside source. Chemical hazards are often present in the kitchen environment, including detergents, floor cleaners, disinfectants and caustic chemicals, which can be harmful if ingested- they are not destroyed through cooking. Physical objects abound in food production facilities, including plastic bits, metal fragments from equipment, staples or twist ties from ingredient packages, and personal objects (e.g., buttons, jewelry, hair, nails.)

There are three main safety precautions that can help control these hazards during all the stages of food production, from receiving ingredients to packaging your final products:

1. Avoid Cross Contamination

  • Prevent biological, chemical or physical hazards from coming into contact with foods
  • Keep equipment, utensils and work surfaces clean and sanitized.
  • Prevent raw foods (as they usually carry bacteria) from coming into contact with “Ready-to-eat” foods (foods that will not be cooked further before consuming).
  • Keep chemicals away from food areas.

2. Personal Hygiene

  • Don’t work around foods if you’re sick with fever, vomiting or diarrhea. These could be signs of contagious illness and can contaminate foods or other staff, and contribute to an outbreak.
  • Do not handle ready-to-eat foods with bare hands, but use a barrier such as utensils, tissues or gloves when handling final products such as pastries or candies.
  • Wash hands and change gloves when soiled or contaminated.
  • Wear hair restraints and clean uniforms, and remove jewelry from hands and arms.

3. Time & Temperature control

  • Prevent bacterial growth in perishable foods such as eggs, dairy, meats, chicken (TCS “Time and Temperature Control for Safety” foods according to the FDA Model Food Code) by keeping cold foods cold and hot foods hot.
  • Refrigerate TCS foods at 41˚ F or below, and cook TCS foods to proper internal temperatures to kill bacteria to safe levels, per state regulations for retail food establishments.
  • If TCS foods have been exposed to room temperature for longer than four hours (Temperature Danger Zone 41˚ F – 135˚ F,) these foods should be discarded, as bacteria could have grown to dangerous levels during this time.

As cannabis companies strive for acceptance and legalization on a federal level, adopting these food safety practices and staff training is a major step in the right direction, on par with standards maintained by the rest of the retail food industry. The only difference is your one specially extracted cannabinoid ingredient that separates you from the rest of the crowd… with safe and healthy edibles for all.

North Carolina Gets First Accredited Cannabis Lab

By Cannabis Industry Journal Staff
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In a press release published on Monday, the American Association for Laboratory Accreditation (A2LA), announced the renewal of accreditation for Global Laboratory Services, Inc. for ISO 17025:2017 in cannabis testing. The laboratory, based in Wilson, North Carolina, becomes first cannabis testing laboratory accredited in that state by adding the industrial hemp testing to their chemical scope of accreditation.

According to Kim Hesse, business development manager at Global Laboratory Services, they plan to expand their services in the hemp market with additional types of hemp testing. “At Global Laboratory Services, we always strive to keep pace with industry needs,” says Hesse. “We saw the need for an accredited laboratory in the hemp industry and therefore added CBD and THC testing to our scope. Our next step is to expand our service offerings to include agrochemical analysis of industrial hemp.”

Adam Gouker, general manager at A2LA, says accreditation plays a vital role in the cannabis industry and its regulatory requirements. “We congratulate Global Laboratory Services on becoming the first cannabis testing laboratory accredited in the state of North Carolina, specifically for industrial hemp,” says Gouker. “A2LA realizes the vital role that accreditation plays in the cannabis industry to support compliance with regulatory requirements, and we are thrilled to see that our service has been adopted in a new state. We look forward to our continued relationship with Global Laboratory Services in the provision of their accreditation needs.”

Doctors & Researchers Push Medical Efficacy Forward at 10th IACM

By Marguerite Arnold
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It is easy to forget as one steps inside this world-class medical conference (held this year in Berlin), that cannabis is disputed as medicine anywhere in the world.

Inside a packed conference hall in an upscale hotel in East Berlin, international researchers presented evidence that when taken as a drug, this simple plant can make a world of difference to patients suffering from a range of illnesses.

There were also doctors who talked about prescribing this as medicine (even to children), with dramatic and affirming results (if not heart-warming pictures).

In sum, as always, the IACM is the best place to find facts if not evidence galore to convince even the most hard-boiled egghead that this drug works – and across a broad range of so far “other” drug-resistant medical conditions.

As a participant in the IACM said after the opening remarks on the very first morning, it is so easy to ask the question – “Why are doctors still so afraid of if not resistant to this drug?”

Medical efficacy is no longer an unanswered question…

For those seeking affirmation and evidence, this year’s IACM did not disappoint. There were presentations on the drug’s impact on neurological, oncological and inflammatory conditions that while not all new, are increasingly impactful in an aging planet.

A full house of attendees for the patients panel

But that is not all that was discussed. The broader implications of adding cannabis into skincare, diets and medicine chests were also presented – from cannabis’ impact on lowering obesity and positively affecting acne to impacting the opioid epidemic.

Also intriguing this year was a far-reaching study on how polluted the CBD supply chain is in Europe, even for non-medical and nutraceutical products. Not to mention a socio-political plea for legalization of personal use in South Africa.

And that was just the presentations from the stage and in the poster hall.

The conversations swirling around were just as interesting. Because of course, nobody at this three-day gathering, for all the normalization on display, did forget that this gathering of doctors, scientists, cannabis companies and patients is still an anomaly.

The fact is that there are still too few doctors prescribing. And too few trials. And too many fights over efficacy still in the room.

As Alice O’Leary Randall (wife and former partner in activism with her late husband, Professor Randall who initiated the medical efficacy fight in the U.S. in 1975 over glaucoma) said to Cannabis Industry Journal, “It is hard to believe that we are still fighting the same fights all over again.”

Another “AIDS” Crisis?

There is a more dramatic sense of urgency at the IACM than other conferences that focus just on the “business.” In part, this is because the conference is made up of not only doctors and researchers who fight to prescribe the drug or get trials funded, but also patients on the front lines in a country where the drug is supposed to be covered by health insurance.

Dr. Franjo Grotenhermen (seen on the table) and others during a panel discussion

The patient panel, as a result, was an international face of accusation: To national authorities who still refuse to mandate cannabinoid care – across Europe and beyond. To medical establishments who are not demanding cannabinoid treatment be made mandatory in hospitals and emergency rooms in every country in the EU and beyond. To individual doctors who refuse to come to such conferences, where, if they wanted to, could learn how to begin prescribing the “next penicillin.” To payers and insurers who are still too slow to pick up the message if not the tab.

Indeed, one of the best panels of the conference was a gaggle of doctors, led by Grotenhermen, who discussed the particulars of approaching a new drug – for the very first patient and first time.

Act Up, Speak Out, Silence Equals Death

As the conference wrapped up with its awards dinner, there was of course, a sense of needing to go home with not wanting this to end. For those in the thick of this multi-generational fight, there of course were words of encouragement to colleagues from the industry, internationally. But there was also a new sense of needing to up the pace, if not create faster change.

The battles are far from over – in fact, they are just beginning in many places. As one questioner said of a panel about halfway through the conference – “We need to pick up the fight the same way the AIDS community did on this drug.”

That remark perhaps means less today than it did 20 to 30 years ago when an embattled LGBTQ subculture was the organized point of the spear that fought the early state legalization battles as pioneers for a cause that sought equality as much as it sought a cure.

The plea did not fall on deaf ears.

In the midst of studies, statistics and scientific evidence, in other words, there was a new sense of a need for a renewed fight – and from the medical and scientific community as well as patients.

Multi-Element Analysis Using ICP-MS: A Look at Heavy Metals Testing

By Cannabis Industry Journal Staff
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Across the country and across the world, governments that legalize cannabis implement increasingly rigorous requirements for laboratory testing. Helping to protect patients and consumers from contaminants, these requirements involve a slew of lab tests, including quantifying the levels of microbial contaminants, pathogens, mold and heavy metals.

Cannabis and hemp have a unique ability to accumulate elements found in soil, which is why these plants can be used as effective tools for bioremediation. Because cannabis plants have the ability to absorb potentially toxic and dangerous elements found in the soil they grow in, lab testing regulations often include the requirement for heavy metals testing, such as Cadmium, Lead, Mercury, Arsenic and others.

In addition to legal cannabis markets across the country, the USDA announced the establishment of the U.S. Domestic Hemp Production Program, following the enactment of the 2018 Farm Bill, essentially legalizing hemp. This announcement comes with information for hemp testing labs, including testing and sampling guidelines. While the information available on the USDA’s website only touches on testing for THC, required to be no greater than 0.3% dry weight concentration, more testing guidelines in the future are sure to include a discussion of heavy metals testing.

Table 1. ICP-MS operating conditions (shaded parameters were automatically optimized during start up for the HMI conditions).

In an application note produced by Agilent Technologies, Inc., the Agilent 7800 ICP-MS was used to analyze 25 elements in a variety of cannabis and hemp-derived products. The study was conducted using that Agilent 7800 ICP-MS, which includes Agilent’s proprietary High Matrix Introduction (HMI) system. The analysis was automated  by using the Agilent SPS 4 autosampler.

Instrumentation

The instrument operating conditions can be found in Table 1. In this study, the HMI dilution factor was 4x and the analytes were all acquired in the Helium collision mode. Using this methodology, the Helium collision mode consistently reduces or completely eliminates all common polyatomic interferences using kinetic energy discrimination (KED).

Table 2. Parameters for microwave digestion.

As a comparison, Arsenic and Selenium were also acquired via the MassHunter Software using half-mass correction, which corrects for overlaps due to doubly charged rare earth elements. This software also collects semiquantitative or screening data across the entire mass region, called Quick Scan, showing data for elements that may not be present in the original calibration standards.

SRMs and Samples

Standard reference materials (SRMs) analyzed from the National Institute of Standards and Technology (NIST) were used to verify the sample prep digestion process. Those included NIST 1547 Peach Leaves, NIST 1573a Tomato Leaves and NIST 1575 Pine Needles. NIST 1640a Natural Water was also used to verify the calibration.

Figure 1. Calibration curves for As, Cd, Pb, and Hg.

Samples used in the study include cannabis flower, cannabis tablets, a cannabidiol (CBD) tincture, chewable candies and hemp-derived cream.

Sample Preparation

Calibration standards were prepared using a mix of 1% HNO3 and 0.5% HCl. Sodium, Magnesium, Potassium, Calcium and Iron were calibrated from 0.5 to 10 ppm. Mercury was calibrated from 0.05 to 2 ppb. All the other elements were calibrated from 0.5 to 100 ppb.

Table 3. Calibration summary data acquired in He mode. Data for As and Se in shaded cells was obtained using half mass correction tuning.

After weighing the samples (roughly 0.15 g of cannabis plant and between 0.3 to 0.5 g of cannabis product) into quartz vessels, 4 mL HNO3 and 1 mL HCl were added and the samples were microwave digested using the program found in Table 2.

HCI was included to ensure the stability of Mercury and Silver in solution. They diluted the digested samples in the same acid mix as the standards. SRMs were prepared using the same method to verify sample digestion and to confirm the recovery of analytes.

Four samples were prepared in triplicate and fortified with the Agilent Environmental Mix Spike solution prior to the analysis. All samples, spikes and SRMs were diluted 5x before testing to reduce the acid concentration.

Calibration

Table 4. ICV and CCV recovery tests. Data for As and Se in shaded cells was obtained using half mass correction tuning.

The calibration curves for Arsenic, Cadmium, Lead and Mercury can be found in Figure 1 and a summary of the calibration data is in Table 3. For quality control, the SRM NIST 1645a Natural Water was used for the initial calibration verification standard.  Recoveries found in Table 4 are for all the certified elements present in SRM NIST 1640a. The mean recoveries and concentration range can also be found in Table 4. All the continuing calibration solution recoveries were within 10% of the expected value.

Internal Standard Stability

Figure 2 highlights the ISTD signal stability for the sequence of 58 samples analyzed over roughly four hours. The recoveries for all samples were well within 20 % of the value in the initial calibration standard.

Figure 2. Internal standard signal stability for the sequence of 58 samples analyzed over ~four hours.

Results

In Table 5, you’ll find that three SRMs were tested to verify the digestion process. The mean results for most elements agreed with the certified concentrations, however the results for Arsenic in NIST 1547 and Selenium in both NIST 1547 and 1573a did not show good agreement due to interreferences formed from the presence of doubly-charged ions

Table 5. Mean concentrations (ppm) of three repeat measurements of three SRMs, including certified element concentrations, where appropriate, and % recovery.

Some plant materials can contain high levels of rare earth elements, which have low second ionization potentials, so they tend to form doubly-charged ions. As the quadrupole Mass Spec separates ions based on their mass-to-charge ratio, the doubly-charged ions appear at half of their true mass. Because of that, a handful of those doubly-charged ions caused overlaps leading to bias in the results for Arsenic and Selenium in samples that have high levels of rare earth elements. Using half mass correction, the ICP-MS corrects for these interferences, which can be automatically set up in the MassHunter software. The shaded cells in Table 5 highlight the half mass corrected results for Arsenic and Selenium, demonstrating recoveries in agreement with the certified concentrations.

In Table 6, you’ll find the quantitative results for cannabis tablets and the CBD tincture. Although the concentrations of Arsenic, Cadmium, Lead and Cobalt are well below current regulations’ maximum levels, they do show up relatively high in the cannabis tablets sample. Both Lead and Cadmium also had notably higher levels in the CBD tincture as well.

Table 6. Quantitative data for two cannabis-related products and two cannabis samples plus mean spike recovery results. All units ppb apart from major elements, which are reported as ppm.

A spike recovery test was utilized to check the accuracy of the method for sample analysis. The spike results are in Table 6.

Using the 7800 ICP-MS instrument and the High Matrix Introduction system, labs can routinely analyze samples that contain high and very variable matrix levels. Using the automated HMI system, labs can reduce the need to manually handle samples, which can reduce the potential for contamination during sample prep. The MassHunter Quick Scan function shows a complete analysis of the heavy metals in the sample, including data reported for elements not included in the calibration standards.

The half mass correction for Arsenic and Selenium allows a lab to accurately determine the correct concentrations. The study showed the validity of the microwave sample prep method with good recovery results for the SRMs. Using the Agilent 7800 ICP-MS in a cannabis or hemp testing lab can be an effective and efficient way to test cannabis products for heavy metals. This test can be used in various stages of the supply chain as a tool for quality controls in the cannabis and hemp markets.


Disclaimer: Agilent products and solutions are intended to be used for cannabis quality control and safety testing in laboratories where such use is permitted under state/country law.