Cannabis  vaping and inhalable products containing phytol

Inhalable cannabis extract products: Phytol

Compliance Directorate

January 15, 2021

In follow-up to the August 2020 letter Health Canada sent to licence holders that produce vaping and other inhalable products concerning phytol, we are writing to inform you that results related to the Canopy Growth Corporation-sponsored study which investigated the inhalational toxicology of phytol have been published in the journal Inhalation Toxicology.

In this experimental animal study, rats were exposed to high levels of aerosolised phytol (a substance that occurs naturally in cannabis and other plants) and which can be added to some cannabis vaping products as a carrier substance or as a component of a flavouring agent. The study observed that exposure to high levels of phytol resulted in serious harm to the rats.

The findings of this single study on animals suggest that inhalation of phytol could pose a potential risk of injury to human health, especially when compared with propylene glycol. However, the extent to which this is likely to happen with human use of certain cannabis vaping products that are currently available in the legal market, which contain small concentrations of phytol, is unclear at this time.

It is important to acknowledge that the study has a number of limitations. For example, the authors of the paper have noted the dose of phytol administered in the study was much higher than the expected human dose, the study was not designed to determine a safe dose of phytol, it is difficult to translate the study findings from rats to humans, and that the aerosols generated in the study may not reflect the aerosols produced when using vape devices. In addition to the limitations identified by the authors, Health Canada notes that some of the particularly long durations of exposure to phytol in the study (up to 6 hours per day) are not necessarily reflective of real-world use.

The study findings were shared with Health Canada in late July 2020 prior to being peer-reviewed and published. As a precautionary measure, in early August 2020, Health Canada contacted licence holders that produce cannabis vaping and other inhalable products to inform them of the study, and to gather more information on products that may contain phytol as an additive. Health Canada also requested that licence holders identify any available safety-related data, studies, or adverse reactions related to phytol in inhalable cannabis products.

Based on the responses received, Health Canada confirmed there are a small number of products on the legal market that contain added phytol, with most products containing phytol estimated to carry concentrations below 2%. One non-serious adverse reaction report associated with a cannabis vaping product known to contain phytol was reported in response to this request. This case appears to be an allergic reaction and it is unclear if the reaction is related to the presence of phytol or due to another component of the product. No additional safety-related data, studies or serious adverse reactions were reported in response to the request.

There are currently no other reports of adverse reactions, including respiratory effects, from phytol containing vaping products reported to Health Canada. Health Canada is not aware of any direct evidence that phytol found in legally available cannabis vaping products has caused injury to health when used as intended or in a reasonably foreseeable way.

Additional studies on the effects of phytol are needed to determine how the study findings could relate to the real world use of phytol in cannabis vaping products. Nevertheless, based on the precautionary principle, Health Canada is encouraging licence holders to review the formulation of any inhalable cannabis extracts containing added phytol and to consider your options carefully, which could include removal of any added phytol from your product formulations. Please note that Health Canada will continue to monitor the situation and that as new evidence becomes available, it may choose to modify its approach.

Health Canada asks licence holders who become aware of any new information on the safety of phytol, including research studies that you commission or are aware of, to notify us and provide any supporting information by email at compliance-cannabis-conformite@hc-sc.gc.ca. Please title your email "[Licence Holder name, LIC-#] - Phytol RESEARCH".

We also ask that you notify Health Canada should you decide to take any voluntary actions on inhalable cannabis extracts containing phytol, such as product reformulation or voluntary stop sale, based on any phytol-related information you may have received. Health Canada requests that you notify us of any voluntary action by email at compliance-cannabis-conformite@hc-sc.gc.ca. Please title your email "[Licence Holder name, LIC-#] - VOLUNTARY ACTION re. PHYTOL".

Health Canada would like to remind all licence holders that under the Cannabis Regulations:

• a cannabis extract must not contain any substances that may cause injury to health to the user when the cannabis product is used as intended or in any reasonable foreseeable way
• all serious adverse reactions must be reported to Health Canada within 15 days of becoming aware of such adverse reactions and that LHs must prepare annual summary reports of all adverse reactions received

Licence holders can find further guidance on adverse reaction reporting for cannabis in the Cannabis adverse reaction reporting guide.

Should you have any other questions or concerns, we encourage you to contact us at compliance-cannabis-conformite@hc-sc.gc.ca.