Tag Archives: contaminated

Heavy Metals Testing: Methods, Strategies & Sampling

By Charles Deibel
No Comments

Editor’s Note: The following is based on research and studies performed in their Santa Cruz Lab, with contributions from Mikhail Gadomski, Lab Manager, Ryan Maus Technical Services Analyst, Laurie Post, Director of Food Safety & Compliance, and Charles Deibel, President Deibel Cannabis Labs.


Heavy metals are common environmental contaminants resulting from human industrial activities such as mining operations, industrial waste, automotive emissions, coal fired power plants and farm/house hold water run-off. They affect the water and soil, and become concentrated in plants, animals, pesticides and the sediments used to make fertilizers. They can also be present in low quality glass or plastic packaging materials that can leach into the final cannabis product upon contact. The inputs used by cultivators that can be contaminated with heavy metals include fertilizers, growing media, air, water and even the clone/plant itself.

The four heavy metals tested in the cannabis industry are lead, arsenic, mercury and cadmium. The California Bureau of Cannabis Control (BCC) mandates heavy metals testing for all three categories of cannabis products (inhalable cannabis, inhalable cannabis products and other cannabis and cannabis products) starting December 31, 2018. On an ongoing basis, we recommend cultivators test for the regulated heavy metals in R&D samples any time there are changes in a growing process including changes to growing media, cannabis strains, a water system or source, packaging materials and fertilizers or pesticides. Cultivators should test the soil, nutrient medium, water and any new clones or plants for heavy metals. Pre-qualifying a new packaging material supplier or a water source prior to use is a proactive approach that could bypass issues with finished product.

Testing Strategies

The best approach to heavy metal detection is the use of an instrument called an Inductively Coupled Plasma Mass Spectrometry (ICP-MS). There are many other instruments that can test for heavy metals, but in order to achieve the very low detection limits imposed by most states including California, the detector must be the ICP-MS. Prior to detection using ICP-MS, cannabis and cannabis related products go through a sample preparation stage consisting of some form of digestion to completely break down the complex matrix and extract the heavy metals for analysis. This two-step process is relatively fast and can be done in a single day, however, the instruments used to perform the digestion are usually the limiting step as the digesters run in a batch of 8-16 samples over a 2-hour period.

Only trace amounts of heavy metals are allowed by California’s BCC in cannabis and cannabis products. A highly sensitive detection system finds these trace amounts and also allows troubleshooting when a product is found to be out of specification.

For example, during the course of testing, we have seen lead levels exceed the BCC’s allowable limit of 0.5 ppm in resin from plastic vape cartridges. An investigation determined that the plastic used to make the vape cartridge was the source of the excessive lead levels. Even if a concentrate passes the limits at the time of sampling, the concern is that over time, the lead leached from the plastic into the resin, increasing the concentration of heavy metals to unsafe levels.

Getting a Representative Sample

The ability to detect trace levels of heavy metals is based on the sample size and how well the sample represents the entire batch. The current California recommended amount of sample is 1 gram of product per batch.  Batch sizes can vary but cannot be larger than 50 pounds of flower. There is no upper limit to the batch sizes for other inhalable cannabis products (Category II).

It is entirely likely that two different 1 gram samples of flower can have two different results for heavy metals because of how small a sample is collected compared to an entire batch. In addition, has the entire plant evenly collected and concentrated the heavy metals into every square inch of it’s leaves? No, probably not. In fact, preliminary research in leafy greens shows that heavy metals are not evenly distributed in a plant. Results from soil testing can also be inconsistent due to clumping or granularity. Heavy metals are not equally distributed within a lot of soil and the one small sample that is taken may not represent the entire batch. That is why it is imperative to take a “random” sample by collecting several smaller samples from different areas of the entire batch, combining them, and taking a 1 g sample from this composite for analysis.


References

California Cannabis CPA. 12/18/2018.  “What to Know About California’s Cannabis Testing Requirements”. https://www.californiacannabiscpa.com/blog/what-to-know-about-californias-cannabis-testing-requirements. Accessed January 10, 2019.

Citterio, S., A. Santagostino, P. Fumagalli, N. Prato, P. Ranalli and S. Sgorbati. 2003.  Heavy metal tolerance and accumulation of Cd, Cr and Ni by Cannabis sativa L.. Plant and Soil 256: 243–252.

Handwerk, B. 2015.  “Modern Marijuana Is Often Laced With Heavy Metals and Fungus.” Smithsonian.com. https://www.smithsonianmag.com/science-nature/modern-marijuana-more-potent-often-laced-heavy-metals-and-fungus-180954696/

Linger, P.  J. Mussig, H. Fischer, J. Kobert. 2002.  Industrial hemp (Cannabis sativa L.) growing on heavy metal contaminated soil: fibre quality and phytoremediation potential. Ind. Crops Prod. 11, 73–84.

McPartland, J. and K. J McKernan. 2017.  “Contaminants of Concern in Cannabis: Microbes, Heavy Metals and Pesticides”.  In: S. Chandra et al. (Eds.) Cannabis sativa L. – Botany and Biotechnology.  Springer International Publishing AG. P. 466-467.  https://www.researchgate.net/publication/318020615_Contaminants_of_Concern_in_Cannabis_Microbes_Heavy_Metals_and_Pesticides.  Accessed January 10, 2019.

Sidhu, G.P.S.  2016.  Heavy metal toxicity in soils: sources, remediation technologies and challenges.   Adv Plants AgricRes. 5(1):445‒446.

Colorado Issues Recall, Pesticides Found In Cannabis

By Aaron G. Biros
No Comments

Last week, the Colorado Department of Revenue (DOR), the Colorado Department of Agriculture (CDA) and the Colorado Department of Public Health and Environment (CDPHE) announced a health and safety advisory for a large number of cannabis products grown and produced by Tree of Wellness Inc., doing business as Tree of Wellness. The health and safety advisory, synonymous with a product recall, was issued due to the detection of off-label pesticides in cannabis grown by Tree of Wellness.

Tests found Myclobutanil present in batches going all the way back to May, 2017, with some contaminated batches as recent as late October.

According to the press release, the CDA confirmed the presence of Myclobutanil, a near-ubiquitous fungicide used in a wide range of agricultural practices. The chemical has been a thorn in the side of the cannabis industry for being used off-label, or inappropriately, on cultivating cannabis.

Here are the batch numbers included in the recall

Myclobutanil is the active ingredient in Eagle 20, a pesticide used frequently in other agricultural fields like grapes, apples and spinach. According to UC Davis professor and Steep Hill scientist Dr. Don Land, Myclobutanil becomes significantly more dangerous when heated, or smoked. That chemical reaction produces hydrogen cyanide, an extraordinarily toxic chemical. Because of this, and the lack of research on what happens when these chemicals are burned or heated, there is a growing public concern that cannabis laced with a chemical like Myclobutanil can cause adverse health reactions.

The public health and safety advisory says they detected Myclobutanil in cannabis flower, trim, concentrates, and infused-products from Tree of Wellness. The CDPHE and DOR recommend consumers that have the affected products return them to where they were purchased for proper disposal.

Consumers in Colorado should check their labels to see if their products fall under the recall. Look for the Medical Optional Premises Cultivation License 403-00664 and/or Medical Marijuana Center License 402-00443. The recall includes batches of 23 different strains grown by Tree of Wellness.

Canadian Company Recalls Contaminated Cannabis

By Aaron G. Biros
No Comments

Broken Coast Cannabis Ltd., a cannabis business located on Vancouver Island, issued a voluntary recall of three cannabis lots due to the detection of pesticides. According to the safety alert published on Health Canada’s website, the voluntary Type III recall follows an inspection of the facility back in March of this year.

A Type III recall means those products are not likely to cause negative health effects. Sampling of those three cannabis lots found a cannabis oil product in July to contain low levels of Myclobutanil and Spinosad.

Upon further testing, a cannabis leaf sample was found to contain 0.017 parts-per-million of Myclobutanil. A third party laboratory confirmed the presence of that fungicide, leading them to recall three lots of dried cannabis sold between July and December of 2016, according to that safety alert.

Spinosad, an insecticide, and Myclobutanil, a fungicide, are not authorized for use with cannabis plants per the Pest Control Products Act, however they are approved for use in food production. The health risks of ingesting either of those two chemicals are well documented. “Health Canada has not received adverse reaction reports related to Broken Coast Cannabis Ltd.’s products sold affected by the recall,” reads the safety alert. “Health Canada recommends that any individual affected by the recall immediately stop using the recalled product and to contact Broken Coast Cannabis Ltd., at the following number 1-888-486-7579.”

Canadian Cannabis Recalls Raise Questions About Choices in Testing Methods

By Aaron G. Biros
6 Comments

Cannabis sold between August and December of 2016 is being voluntarily recalled by Organigram, a Canadian cannabis producer, due to the detection of unapproved pesticides, according to a press release. Organigram is a licensed medical cannabis producer in Canada, which received an organic certification back in 2014 by ECOCERT, a third-party organic certification organization based in France.

health-canada-logo

Organigram and Health Canada deemed it a Type III recall, meaning “a situation in which the use of, or exposure to, dried marijuana, fresh marijuana or cannabis oil, marijuana plants or seeds is not likely to cause any adverse health consequences,” according to that press release. They don’t know how the products were contaminated as routine use of pesticides is barred under their organic certification. Organigram is cooperating with Health Canada to conduct a full investigation to determine how the cannabis was contaminated.

About a month before Organigram’s recall, Mettrum Health Corp., a Toronto-based licensed medical cannabis producer, voluntarily recalled medical cannabis products that might have contained trace levels of pyrethrin, an insecticide not approved for use on cannabis, but generally regarded as safe with a low toxicity. That press release only mentions the detection of pyrethrin and downplays the health effects. “While the ingredient is not harmful and there is no negative effect on product quality and safety, we are doing everything possible to ensure client satisfaction and confidence is upheld,” says Michael Haines, director and chief executive officer of Mettrum Health Corp.

Pesticide Use was a major issue of 2016 Photo: Michelle Tribe, Flickr
Photo: Michelle Tribe, Flickr

Reporting in an article last week, The Globe and Mail discovered that Mettrum’s recall included lots where they detected trace levels of Myclobutanil, a hazardous and illegal pesticide that is banned in a number of states as well. Myclobutanil has been discovered as the culprit in a slew of pesticide-related recalls in Colorado and Washington.

But Mettrum’s updated press release doesn’t include any mention of Myclobutanil. Health Canada also didn’t make any public disclosures addressing the detection of Myclobutanil. The Globe and Mail only found out that the recall included the banned pesticide after asking a Mettrum employee.

teganheadshot
Tegan Adams, business development manager at Eurofins-Experchem

Tegan Adams, business development manager at Eurofins-Experchem Laboratories, Inc., a Toronto-based GMP testing lab, indicated that while the regulations are clear in their statement on zero tolerance for pesticides- reasons for inconsistent testing results are in part related to variations in rigor of testing methods available to monitor for pesticides in cannabis. “Licensed producers do not have to release routine test results to the public,” says Adams. “There is a group of us, inclusive of representatives from licensed producers (LPs), working on proposing a new federal cannabis accreditation standard that would make testing results, grading quality, DNA and a few other things public for each cannabis batch legally released to the public to be accredited. Making information like this public would help remove a lot of consumer scrutiny on LPs, as it currently exists in the marketplace. Most of them care so much about their products and patients, they work very hard to create safe quality products”

According to Adams, routine pesticide testing typically scans for roughly 100 pesticides. She says a more rigorous test could scan for 500-700 different pesticides, a more accurate representation of what’s on the market. Adams says the regulations have zero tolerance for any detection of pesticides, not necessarily an action level for what is a safe amount to be present.

Toronto Photo: Paul Bica, Flickr
Toronto
Photo: Paul Bica, Flickr

More research is needed on the smoking and inhalation aspects of pesticide products to say what is safe and what is not. “There are different methods available to test for pesticides, and SOPs to follow to avoid their application,” says Adams. “But if a licensed producer chose a testing method that doesn’t for some reason cover a pesticide they are later found to have on their product, that could present the need for a recall if Health Canada or another entity were to somehow to detect it using a different method.”

Health Canada determined both of those recalls to be Type III recalls. Both companies said they are cooperating fully with the regulatory body. By embracing the proposed new cannabis testing accreditation standard, Health Canada could remedy the testing methodology discrepancies and require a greater level of transparency.

Oregon Issues Health Alert for Contaminated Cannabis

By Aaron G. Biros
No Comments

According to Jonathan Modie, spokesman for the Oregon Health Authority (OHA), on Friday, October 21st, the OHA issued a ‘health alert’ regarding cannabis products sold from a McMinnville dispensary that were possibly tainted with extremely high levels of Spinosad, an insecticide commonly used to combat mites and other pests. “My understanding is that two medical patients purchased the cannabis products whom we had contact info for, but most of the purchasers were recreational customers,” says Modie. “Because it is not required to get contact info for recreational customers, we issued the health alert to get the word out as quickly as possible because we didn’t know who bought the product.” The OHA is urging consumers who purchased cannabis from New Leaf CannaCenter in McMinnville to check the labels and see if they purchased potentially dangerous cannabis, and to either return the cannabis to the dispensary or dispose of it appropriately.

oha_logo_lrgThe action level, the measured amount of pesticides in a product that the OHA deems potentially dangerous, for Spinosad is 0.2 parts-per-million (PPM). The two batches in question are the strains Dr. Jack (batch number G6J0051-02) and Marion Berry (batch number G6J0051-01), which were tested to contain approximately 42 PPM and 22 PPM respectively, much higher than the OHA’s action level.

While this is the first health alert issued in Oregon in connection with potentially contaminated cannabis, Modie says he expects there will be more health alerts in the future. “Unfortunately the product was inappropriately transferred from the grower to the dispensary and from the dispensary to customers, so we are working to get the word out to dispensaries, growers and processors about the testing rules to prevent this from happening in the future,” says Modie. “We want to make it clear that any grower, processor or dispensary that does not follow the testing requirements or fail to label, store or retain batches that fail a test will be subject to enforcement actions such as fines, penalties, suspension or revocation of their license.” The OHA has a list of pesticide analytes and their action levels on their website.

“We are advising recreational and medical users alike to read the product labels closely; the labels must have the license or registrant number, the packaging or distributor license number, the name of the strain and the universal symbol,” says Modie. “We are also suggesting consumers request a copy of pesticide test results from the dispensary.” It is unclear at this time if all of the cannabis products in question have been properly disposed of, but OHA was informed that New Leaf has pulled all products in question off of the shelf.