In a jurisdiction where cannabis is prohibited by law there is little if any protection for consumers of cannabis or cannabis extracts. To protect people from contaminated cannabis products, quality control and the laboratory testing of cannabis and cannabinoid preparations is essential.
In an uncontrolled, unregulated market it is very common to find cannabis contaminated with pesticides, heavy metals, toxins and microorganisms. It is also quite common to find products containing mould spores, bacteria and fungus, these contaminants can have a detrimental effect on health, which can be compounded if people are using cannabis for medicinal purposes and they have a compromised immune system.
Producers of pharmaceuticals, food and drink products are strictly regulated and they are required to submit to third-party testing to verify the safety of their products, unfortunately, there is no basic level of safety or quality control under a decriminalised or prohibitive (cannabis) system.
As well as testing for contaminants the potency of cannabis products is also important to cannabis consumers. To protect the consumer and the general public a testing and labelling scheme for cannabis and cannabinoid preparations is required, imagine the chaos if alcohol was not tested and labelled accordingly, the effects of drinking a glass of vodka are very different to drinking a glass of beer.
As the cannabis market develops and matures so will the demand for cannabis concentrates and cannabis extractions.
Cannabinoids are extracted from cannabis plant material by the use of a solvent, butane, hexane, isopropyl alcohol and ethanol are commonly used to produce cannabis concentrates, however, unless the products are tested for solvent residues some of the solvent used in the extraction process can remain in the final product and some of these residues can be detrimental to health.
Cannabis cultivators and processors should have access to the following tests:
- Microbiological test – testing for moulds, bacteria and fungi
- Potency testing of cannabis flowers (cannabinoid profile)
- Solvent residue testing
- And ideally, terpenoid testing
In Spain Bud Buddies have access to testing facilities, they use HPLC testing for all their cannabinoid extracts
All preparations are labelled.
This 1:1 extraction contains 39.5% THC and 37.8% CBD, total cannabinoid content 80.3%
The HPLC test shows that the extraction is fully decarboxylated and based on these results preparations with standardized doses can be produced.
There are two main types of testing, Gas Chromatography (GC) and High-Performance Liquid Chromatography (HPLC).
Gas chromatography (GC) is a common type of chromatography used in analytical chemistry for analysing compounds that can be vaporized without decomposition. Typically, GC analysis is used to determine the purity of a substance, samples are converted to a gas and the gas is then analysed.
High-performance liquid chromatography (HPLC) is another process used in analytical chemistry to separate, identify, and quantify the individual components in a mixture of compound, HPLC analysis is more suited to the testing of cannabis extractions and preparations than the plant material itself.
Cannabinoids produced by the plant are in their natural acid state and to be bioavailable they require transforming from their acid form to a neutral form, this is achieved by the application of heat (or UV light), this process is called decarboxylation. For example, to make THC-acid effective it has to be converted from THC-a to THC, when you inhale cannabis via smoking or vaporisation THC-a is converted (by heat) from THC-a to THC.
However, if THC-a is orally ingested the acidic cannabinoids will remain in their original state and bioavailability will be greatly reduced s THC-a has a low affinity for CB1 receptors.
HPLC analysis allows us to identify the major cannabinoids present in both their acid and neutral forms, GC testing converts cannabinoid acids into cannabinoids so therefore is unsuitable for the testing of orally administered cannabinoid preparations. As HPLC testing does not use heat it can be used to identify and quantify both the acidic and neutral cannabinoids in a sample and this is our preferred testing method. We would require HPLC analysis for cannabinoid extractions, preparations and other products such as medibles, edibles and topicals.
The decision to use GC or HPLC testing will depend on the type or form of the sample and its end purpose.
Terpenes are the chemical substances responsible for the aroma of cannabis and many express their own medicinal properties, e.g. anxiolytic, anti-inflammatory, analgesic and neuroprotective effects.
Common terpenes present in cannabis varieties are α-Pinene, β-Pinene, limonene, myrcene, linalool, and β-caryophyllene.
Mould and bacteria exist everywhere and while not all forms are harmful, some microorganisms such as E. coli can be very dangerous.
High levels of microorganisms can be avoided by following good hygiene practises during the cultivation, processing and storage stages.
In Spain in 2014 our colleagues at Fundación CANNA at Valencia University carried out a study in cooperation with 31 Cannabis Social Clubs (CSC’s), over 50 individual samples of cannabis were analysed. The aim of the study was to identify and determine the microorganisms present and they were present in 80% of the samples analysed.
Some of the potentially pathogenic microorganisms that can be found in Cannabis:
Aspergillus genus, spores occur naturally in the environment and they develop rapidly in environments with high humidity levels, they can lead to the production of mycotoxins (aflatoxins) which are highly carcinogenic substances.
Their presence can lead to Aspergillosis, ill people with a compromised immune system can struggle with this fungus and its presence is especially dangerous to people with immunosuppressive disorders.
Penicillium genus, many people are allergic to penicillin.
Enterobacteriaceae, are normally found in soil and faeces and their presence is generally indicative of poor hygiene measures, cultivating with poorly formulated organic fertilisers can also result in contamination. Two enterobacteriaceaes which can be present in cannabis are E.coli and salmonella.
The spores of fungi are often inhaled during smoking and although some of the spores are destroyed (via incineration) the ones not subject to the source of combustion can easily reach the lungs. Cannabis that has not been correctly dried, cured or stored provides an ideal medium for the development of fungi.
Cannabis bud (flowers) should be labelled with the following (minimum) information:
Strain, name of producer, batch number, THC, CBD and CBN content, net weight.
With access to such information a cannabis consumer can estimate their cannabinoid intake, e.g. if a consumer uses half a gram (500 mgs) of this Blueberry haze in a joint then they can calculate that their joint will contain 83.5 mgs of THC (16.7% x 500 mgs)
In addition to the information required for labelling bud (flowers), there will also be a requirement to inform on dose per serving for edibles and medibles.
This chocolate bar contains 80 mgs of THC and comprises of 8 squares of chocolate, therefore the amount of THC per serving (or square) is 10 mgs.
Cannamol is a sublingually applied preparation containing both THC & CBD produced in Spain.
|Labels inform on the total amount per vial of active ingredients (THC & CBD) and per drop.
|All products have a batch number, 1ml = 20 drops.
Labelling is redundant if the consumer does not understand the information
There is also a need for a public education campaign to inform the public and cannabis consumers on how the information provided on the packaging should be interpreted.
In addition to educating the public on ‘safe practise’, labels should also carry prominent warnings regarding “Keep out of reach of children”
One of these Gummy Bears contains THC, but which one?
The one on the left contains 100 mgs of THC
Cannabinoid testing kits are available:
Combining the straightforward diagnostic technique of thin-layer chromatography with specific thin-layers and developing fluid, the alpha-CAT test kit can identify six cannabinoids present in your plant material and their levels of concentration.
Each Regular Kit allows the user to conduct between 10 and 40 tests. This simple method enables anyone to expose the active cannabinoid profile in medicinal materials, regardless of your scientific understanding. Order: Here