Home » Research Paper: ACI and CMC Recommend Home Office Clarifies THC Limits for CBD Products

Research Paper: ACI and CMC Recommend Home Office Clarifies THC Limits for CBD Products

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Experts from the Association for the Cannabinoid Industry (ACI) and Centre for Medicinal Cannabis (CMC) have put together a detailed safety review paper of THC –  Health Guidance Levels for THC in CBD products: Safety Assessment & Regulatory Recommendations. The paper recommends further research and makes policy recommendations.

Cannabidiol (CBD), extracted from the Cannabis Sativa plant, has attracted a rapidly growing consumer interest as a wellness product. Whilst CBD itself is not a controlled substance, there are at least 12 potential controlled contaminants in CBD products including various tetrahydrocannabinol (THC) compounds.

There is confusion among the public and UK businesses relating to the control status of products containing hemp, CBD and other cannabinoids. The Home Office interpretation presumes that all CBD products are controlled even when no controlled contaminants are detectable. This presumption is incompatible with scientific convention and is likely to be incompatible with case law.

In most European countries, maximum levels have been agreed for controlled cannabinoids in products for consumer use. This ranges from 0.001 mg/kg (EU (EFSA) and Germany) to 0.007 mg/kg THC in consumer products (Switzerland and Croatia), as well as THC limits in CBD end products (ranging from 0.05% in the Netherlands to <3% in Guernsey).

Recommended safety limits

To address the UK regulatory anomalies, our report, which has been submitted to the Home Office and the FSA, has independently considered all the available data and recommends a THC safety limit of 0.03% or 21 μg per day. The paper recommends that in finished products, if levels of THC and other controlled cannabinoids is below 0.03%, then the product should be treated as “zero-THC” and therefore not subject to any restrictions of the Misuse of Drugs Regulations.

We recommend that the proposed safety limit of 0.03% accounts for the total controlled cannabinoid limit in CBD food and consumer products (including other THCs and CBN, which are less common and potent than Δ9THC). This level of THC is highly unlikely to produce a positive THC drug test.

Further to this, the paper recommends that CBD products containing between 0.03 percent and 0.2 percent controlled cannabinoids should be classified under Schedule 5 of the Misuse of Drugs Regulations act of 2001, making them lawfully available for over-the-counter supply in the UK.

We fully understand that tackling drug misuse, and the harm it causes, is a top priority for the UK Government,” explains Dr Parveen Bhatarah, Regulatory and Compliance Associate, ACI and CMC. “CBD is not a controlled drug but any plant-derived CBD has potential to contain controlled cannabinoids. However, the Misuse of Drugs Regulations 2001 for CBD products demands that it contains no more than a defined trace percentage of controlled cannabinoids as an impurity. This paper has taken into account the analytical challenges, testing methodology challenges and existing scientific evidence base data to propose the safe limit for controlled cannabinoids. This approach can overcome the challenges the CBD industry is currently facing which is important for the sustainability of the industry. Meanwhile, the ACI team is generating further evidence based data on the safety of CBD-based consumer products to ensure the UK’s CBD industry is providing safe CBD to consumers.

Research recommendations

Based on a gap review of the available literature, the paper outlines six key proposals for future research.These include:

  1. Further animal toxicology studies on the effects of purified cannabinoids, such as CBD, Δ9-THC, Δ8-THC, and CBN.
  2. More studies into the dose-dependent effects of these isolated cannabinoids in humans.
  3. Randomized, placebo-controlled trials of these cannabinoids when combined in humans.
  4. Further observational studies into CBD consumer behavior in the UK.
  5. Surveillance studies on consumers to monitor safety and tolerability.
  6. More trials to assess how CBD products may affect drug tests.

Policy recommendations

This evidence based initiative is important to allow a threshold for THC to be set in consumer CBD products that is safe for consumers and society, is enforceable by regulators and can be adopted by manufacturers,” says Dr Andy Yates, Scientific Associate for ACI and CMC. “By adopting these recommendations the UK can establish itself as a leading jurisdiction in setting unambiguous, enforceable, evidence based standards for CBD products, which the industry and the consumer has been calling for over the last few years.

Underpinning any recommendations on the levels of controlled cannabinoids in consumer products, is the principle of protection of the consumer from harm and compliance with the law,” adds Dr Paul Duffy, ACI Toxicology Associate. “We considered that to be the primary objective of our scientific review and evaluation of the advances in analytical detection chemistry for human and animal toxicological data on THC. We also believe that these principles are at the core of any considerations of the FSA and Home Office. In modern society, evidence based decisions, underpinned by sound robust scientific data should be at the heart of safety for the consumer and we consider that the ACI/CMC report adheres to that.  In my opinion, the proposed levels of THC are reasonable and manageable from a safety and legal perspective.

On the basis of the literature review and safety assessments in this paper, we make the following policy recommendations:

  1. That CBD products containing between 0.03 percent and 0.2 percent controlled cannabinoids should be classified under Schedule 5 of the Misuse of Drugs Regulations act of 2001, and so should be lawfully available for over-the-counter supply in the UK.
  2. That the Home Office consider exempting dried hemp leaves and flowers from drug controls where the hemp has been lawfully grown or imported into the UK.
  3. That the FSA require CBD companies to include warning labels for those at higher risk of adverse events.
  4. That the FSA consider post-marketing surveillance measures, such as a consumer app, to better identify product health risks.
  5. That the Home Office issue updated public guidance to clarify the legal controls on the manufacture and possession of products containing CBD and other cannabinoids.
  6. That the Home Office and FSA issue joint guidance to the CBD industry regarding the regulations and requirements for the transport, manufacture, and supply of CBD-based novel and non-novel food products.

Health Guidance Levels for THC in CBD products: Safety Assessment & Regulatory Recommendations

The paper was jointly published by ACI, CMC and Conservative Drug Policy Reform Group (CDPRG). It was written by Dr Parveen Bhatarah (Regulatory and Compliance Associate, CMC & ACI), Dr Paul Duffy (Toxicology Associate, ACI), Dr Andy Yates (Scientific Associate, CMC & ACI), Dave King (CDPRG), and peer reviewed by Professor Saoirse Elizabeth O’Sullivan. The paper will be further peer-reviewed and published as an academic paper.