Guidance on analytical limits for controlled cannabinoids
The Government Chemist team has published guidance on analytical limits for controlled cannabinoids in specified products containing cannabidiol (CBD)
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This advice applies to materials and products used in the supply or manufacture of cosmetic products (Cosmetic Products Regulations 2013, No 1478) or novel foods as defined by the relevant legislation (Novel Foods (England) Regulations 2018, with devolved equivalents).
The text including references, figures and tables is complete in the attachment. The main points are included in the summary below.
Background
Cannabidiol (CBD) is a non-psychoactive cannabinoid present in the cannabis plant (Cannabis sativa L) along with many other cannabinoids that may either exhibit psychoactive or non-psychoactive properties.
CBD plant extract or plant isolates are preparations identified as ingredients in some cosmetic products or food supplements supplied to the UK market.
The process of extracting or isolating CBD from the cannabis plant is likely to co-extract other cannabinoids depending on the efficiency of the extraction process and could unintentionally include other non-psychoactive or, more significantly, psychoactive cannabinoid substances.
The UK Misuse of Drugs Act (MDA) with its subordinate regulations prohibit the supply of certain psychoactive cannabinoid substances depending on which part of the cannabis plant has been used. To aid understanding of the legislation, the Home Office produced general guidance in relation to the supply of products containing CBD titled ‘Drug Licensing Factsheet-Cannabis, CBD and other cannabinoids’. The factsheet explains ‘some products may, in limited circumstances, be considered ‘exempt’ from control, notwithstanding their ‘controlled drug’ content… The exemption is a three-limbed definition but for the purposes of this note the relevant limb is ‘(c)’, “…provided (‘c) no one component part of the product or preparation contains more than one milligram of the controlled drug…’
The ‘controlled drug’ content ‘threshold’ of one milligram when considering the exemption provides a content measurement enabling manufacturers using CBD derived plant extracts or isolates in preparations or products to demonstrate a de minimis inadvertent presence of psychoactive cannabinoid substances that might not contravene legislation.
Although a de minimis amount of one milligram (0.001 g) for the ‘controlled drug’ in a product or preparation appears straightforward, it presents difficulties in interpretation and analysis.
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The ‘controlled drug’ could comprise one or more prohibited psychoactive cannabinoid compounds.
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Determination of content is necessarily made indirectly by measuring concentration, which is amount per given mass or volume.
There is uncertainty over whether the ‘controlled drug’ content ‘threshold’ of one milligram applies to each illicit cannabinoid or the total sum of illicit cannabinoids given there are a number of prohibited psychoactive cannabinoids. As the legislation is unclear, a worst-case approach has been taken for measurement purposes in this guidance to assume the 1 mg threshold covers all psychoactive cannabinoids, although in practice only a limited number of psychoactive cannabinoids are determined analytically to assess compliance. This means the content threshold will be the sum of compounds, requiring each compound to be determined at a sufficiently low level to decide whether, or not, the summation of compounds exceeds the one milligram content threshold. Concentration measurements become more difficult because increasingly more sensitive methods are required to detect lower concentrations to demonstrate the one milligram content has not been exceeded.
Points covered in the guidance
The guidance covers the following issues:
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Psychoactive cannabinoid compounds: there are twelve stereoisomeric cannabinoid compounds identified as naturally present in the cannabis plant which presents analytical and practical challenges.
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Concentration: The accepted view is that the applicable unit of measure for the 1mg ‘threshold’ is the ‘container’ (i.e. bottle or packet) and not the ‘typical dose’ (of any product). This view has implications in the required detection limits for the analytical method.
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Combining factors: the ‘controlled drug’ may not consist of a single compound but could include all twelve psychoactive cannabinoid compounds that when added together may exceed the one milligram threshold. Consequently, each psychoactive cannabinoid compound requires detection at a lower concentration. Combining the effects of the number of psychoactive cannabinoid compounds with varying quantities of preparation or products will provide the minimum concentration a detection system will need to achieve.
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Calculation: this section describes the factors that need to be taken into account to determine suitability of the method for the detection of controlled cannabinoids depending on product quantity.
This guidance was prepared under the BEIS GC Programme with contributions from other government departments.
For information about the work of the Government Chemist please contact:
Last updated 1 February 2021 + show all updates
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The guidance has been update to correct an error to the figure for oral liquids in Table 4 on page 7, which now reads < 0.00833 mg/mL rather than 0.0833 .
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Report has been updated to reflect minor corrections
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First published.