The UK Needs A 0.03% THC Limit for CBD Products, Says Industry Group

Across Europe, most counties have agreed upon THC safety limits for commercial CBD products. Most hemp derived food products sold within the European Union, for instance, are subject to the union’s safe THC limit of 0.001 milligrams per kilogram of body weight (mg/kg). While in Switzerland, which operates outside of the EU, CBD products can contain up to 0.007 mg/kg of THC.

But what about the UK? Having left the EU at the start of 2021, the country is now without any such THC safety limits for CBD products.

Given the sheer scale of the country’s CBD sector (estimated to be worth £300 million a year) and the incoming CBD regulations from its Foods Standards Agency (FSA), it’s likely a THC limit will be drawn up at some point. But what should it be? Well, one group of leading CBD experts have an answer.

As outlined in their soon-to-be published report “Health Guidance Levels for THC in CBD products,” the industry group recommend that the UK Home Office enacts a cap of 0.021 mg/kg of THC (and other cannabinol derivatives) per day. This limit would be equivalent to permitting 0.03 percent THC per the recommended 70 mg daily intake of CBD.

It’s one of many recommendations the authors – who are affiliated with either the Centre for Medicinal Cannabis, the Association for the Cannabinoid Industry, or the Conservative Drug Policy Reform Group – make in their report, which was exclusively shared with Analytical Cannabis ahead of its publication.

Room for improvement

To begin their report, the authors first began a review of the CBD safety regulations of the European Union, the World Health Organization, and countries such as Australia and New Zealand. Another review of scientific literature relevant to THC safety limits was also undertaken.

While significant gaps in CBD-THC safety data were noted, the authors still had a good deal of literature to help calculate their THC cap.

A 2015 report from a European Food Safety Authority (EFSA) panel, for instance, listed an acute reference dose for THC (and other cannabinoids) to be around 0.001 mg/kg per day. Seeing no reason to dispute this, the authors of the new report added an “uncertainty factor” of 2 to account for any pharmacokinetic effects. Another uncertainty factor of 2 was then added to account for consumers exceeding the recommended daily allowance of CBD. Once these factors were applied to the EFSA figure, the authors of the new report came to 0.021 mg/kg per day figure, which is roughly equivalent to 0.03 percent of the recommended daily dose of CBD in the UK.

“When you calculate these tox [toxicology] studies, you put in all those uncertainty factors to ensure that you can never be over and above the tox rate,” Dr Parveen Bhatarah, the regulatory lead at the Association for the Cannabinoid Industry and co-author of the report, explained to Analytical Cannabis.

“But real time, actual scientific evidence data is required,” she added. “And that’s why we are recommending that we do need to have further research to ensure that, possibly, that dose is higher than what we’re recommending at the moment.”

This research recommendation is also detailed in Bhatarah’s report, which 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.

The findings from these studies could help inform CBD health and safety guidance in the future. But even without such insights, Bhatarah and her colleagues already have a few recommendations for CBD regulations and policy. Alongside their key proposal – that the Home Office exempt CBD oils that contain 0.021 mg/kg of THC from UK drug legislation – the authors also recommend:

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, such as pregnant people.
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.

The report has already been shared with both the UK Home Office and the FSA. Discussions on implementing its recommendations, however, have differed between the two government bodies, given their different priorities.

“At the moment, they [the Home Office] are really taking it with open hands and really accepting what we have proposed,” Bhatarah told Analytical Cannabis.

“I have shared this report with the FSA,” she added. “However, we haven’t had the particular labelling conversation in depth yet because there has been so much discussion regarding the novel foods and validation.”

Last year, in a major shake-up for CBD regulations in the UK, the FSA announced that all CBD businesses operating in England and Wales must have a novel foods application “validated” by March 31, 2021, or risk having their CBD oils, drinks, and treats “taken off the shelves.” But then on March 11, with just two weeks left until this deadline, the agency updated its guidance. Now, CBD businesses just have to have their applications “validated” by the end of the month – a change of phrase that has afforded companies more time to meet the needs of the validation process.

“Last week they expanded the deadline, from validation to submission by 31st of March” Bhatarah said. “They are, at the moment, so tied up ensuring that they have a smooth path to get these applications validated.”

Future regulation

This isn’t the first time the Home Office has received advice on where to set a “THC cap” on consumer CBD products. On January 11 this year, Kit Malthouse, the minister of state for crime and policing, wrote to the chair of the UK’s Advisory Council on the Misuse of Drugs (ACMD) and recommended a different threshold than the one proposed by Bhatarah and her colleagues.

“In terms of this trace amount, we propose that the defined trace percentage in CBD products be set at a level which will be between 0.01% and 0.0001% by weight per controlled cannabinoid,” the minister wrote.

But this standard, if implemented, would be missing some of the uniformity afforded by the one recommended in Bhatarah’s report.

“So, they are proposing that somewhere between 0.01 and 0.0001 percent should be allowed, and we are saying point 0.03,” she explained to Analytical Cannabis. “And this 0.03 is for the total of the controlled cannabinoids. They are saying for the individual controlled cannabinoids.”

Currently, there are at least 12 controlled contaminants, including THC, that can be found in consumer CBD products in the UK. So, theoretically, Malthouse’s standard could afford up 0.12 percent by weight of all cannabinoids – a figure four-fold higher than Bhatarah’s total 0.03 percent cap.

“We are actually at the lower end of the higher end, which the Home Office have proposed to the ACMD,” she said.

But whichever standard is ultimately chosen as the UK’s de facto THC cap, Bhatarah says, it will have to be substantially evidenced by rigorous studies.

“We all know that in order to propose [any cap] we need appropriate evidence-based data to support that those limits,” she added.