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Blackmarket medical cannabis in New Zealand, mostly not as claimed

A new paper published by scientists at ESR has confirmed the cannabinoid content of New Zealand's illicitly-sourced medicinal cannabis products vary widely, and claimed cannabinoid ratios in most products are incorrect.



Green Fairies is a colloquial term in New Zealand for those who offer a compassionate service that connects patients with cannabis products, sourced from the unregulated market, for medical purposes. They work with many patients who have been unable to access cannabinoid products through the regulated health system.


However, there can be some risks associated with taking illicitly-produced cannabis products to treat health conditions, especially in children. Most notably, illicit products are not tested for their claimed active cannabinoid content, nor for potential contaminants.


This post shares observations from ESR, New Zealand’s Crown Research Institute specialising in science for communities.


The green fairy phenomenon


The following report was published in the Australian Journal of Chemistry by Raymond Onyekachi, McCarthy Mary Jane, Baker Jess, Poulsen Helen (2021) Medicinal Cannabis – The Green Fairy Phenomenon. Australian Journal of Chemistry 74, 480-494 (link)


Frustration at the restrictions to access prescribed cannabinoids in New Zealand has resulted in a black market of home-made cannabis-based products for medicinal use.


These products are being made, and marketed illegally, by individuals calling themselves ‘Green Fairies’. The products take many forms and are being used to treat a range of illnesses and symptoms including pain, insomnia, anxiety, and seizures.


Analytical extraction methods were developed to determine the cannabinoid content in a variety of matrices, principally those that are soluble in methanol and those that are soluble in hexane.


An LC-MS/MS method was developed that detected THC, THCA, CBD, CBDA, CBG, CBGA, CBN, THCV, and CBC with lower detection limits around 0.001 mg of cannabinoid per gram (mg g−1) of product.


One hundred ‘Green Fairy’ samples have been analysed to determine the cannabinoid content, including 12 fully extracted cannabis oil (FECO) samples, 12 ethanolic tinctures, 6 vape juices, 39 oily liquids with olive oil, hemp seed oil, or medium chain triglycerides (MCT) as a base, and 31 waxy solids made using coconut oil.


Nine named cannabis plant cultivars purported to be used to make these products have also been analysed.


Cannabinoid potency testing in an analytical laboratory

The results of the analyses show that these Green Fairy products contain a wide range of cannabinoid concentrations and the claim that a product was high in CBD was often not correct.


The proposed dose size was not specified for these products, but few would provide what is considered an effective dose when compared with the administration of commercially purified cannabinoid products available by prescription.


For many products the manufacturer had specified which cannabis cultivar had been used but a comparison of cannabinoid ratios showed a lack of consistency within products said to be made from the same strain.


Analysis of named cannabis cultivars available showed little variation in the relative amounts of THC and CBD.


ESR is New Zealand's Crown Research Institute that specialises in science relating to people and communities.


Safety a concern


ESR is one of the country’s main drug testing laboratories and says, with Parliament having given the green light permitting a medicinal cannabis industry, it’s crucial that an evidence-based regulatory process is developed that defines strict quality standards.


Dr Mary Jane McCarthy, ESR's Forensic Toxicology and Pharmaceuticals Manager

Dr Mary Jane McCarthy, says there also needs to be robust safety data to ensure the products are safe and are shown not to cause harm to the people that use them. She says there is a lot of confusion about medicinal cannabis.


“Our concern is that people don’t necessarily know or understand what is in the product they are taking. We have had a number of the medicinal cannabis products available here in New Zealand – supplied to us by concerned patients and parents – and our tests have shown that there’s quite a lot of variability in the quality of products with some difference in the concentrations of the active ingredients,” Dr McCarthy says.

That includes tetrahydrocannabinol (THC), the psychoactive component of cannabis, and cannabidiol (CBD), which is not psychoactive. CBD has now been rescheduled so that it is no longer a controlled drug and is only a prescription medicine under the new law changes. Products containing it should become more available to patients from now on.


“We see a range of products – imported and homemade. Some of them have much higher concentrations of THC than they are stated to. We really do need to be testing and understanding the safety of these products and make sure they are effective for the condition which they are being used for, and won’t cause harm", she says.

Dr McCarthy cites one instance when a worried grandfather contacted ESR about the product his grandchild was using for uncontrolled epilepsy. “In this case, there should have been high CBD and low THC – in fact it was the opposite. I would be very worried about a child taking a product like that.”


Testing the fairies


The follow is an excerpt from a related article written by Russell Brown, published on Public Address (24 June 2021). You can view his full story here.


A new paper by ESR scientists, published in the Australian Journal of Chemistry, has confirmed what close observers of the local cannabis community already knew, or at least suspected: the cannabinoid contents of local “green fairy” products vary widely, ratios in many products are not as claimed – and most products claiming to be high in CBD are not.

But, short of real regulation, a solution is in the wings – via the drug-checking law currently making its way through Parliament.


In 2019, the ESR scientists collected and tested a hundred green fairy products, most of them passed on via the Auckland Patients Group (a compassionate service providing access to unregulated cannabis products for media purposes). They included cannabis flower, FECO (fully extracted cannabis oil), carrier oil preparations, balms, tinctures and even vape liquids.

Russell Brown, journalist

The results in this subsequent paper, Medicinal Cannabis – The Green Fairy Phenomenon, are not entirely news: ESR Forensic toxicology and pharmaceuticals manager Mary Jane McCarthy, who led the project, warned in February 2019 about a “product administered to an epileptic child, which “should have been high CBD and low THC – in fact it was the opposite. I would be very worried about a child taking a product like that.” She presented the testing results last November at the inaugural MedCan Summit in Auckland – and said that the testing ended because ESR's funding ran out.


I noted at the time that there was “a compelling harm reduction rationale for continuing to test these products and sharing the results.” It now seems likely that will happen, via the Drug and Substance Checking Legislation Bill (No 2), which replaces the temporary legislation introduced to allow drug-checking at events last summer and is now at select committee. Like the temporary version, the bill aims to “try to minimise drug and substance harm by allowing drug and substance checking services to operate legally in New Zealand.”



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