Phytol is an oil thinning agent of great interest to vape manufacturers due to its food-safe flavouring properties, and just like terpenes, it naturally occurs in cannabis. Health Canada recently provided an announcement regarding the use of phytol in inhalants describing new guidance to manufacturers. Taken from the peer reviewed research study by Schwotzer et al, (2021) published in the Journal of Inhalation Toxicology, Health Canada warns of the concentration relationships with aerolised phytol, propylene glycol (PG), and measured toxicity in animals exposed to cannabis vape formulations. Moreover, an open call for more consultation and research to translate these inhalation risks to human health.
The researched toxicology profiles of phytol and PG was carried out using controlled aerosol systems in rodent models. Dosed concentrations of phytol and PG from ~5 mg/L formulations were introduced over step-wise rates for 6 hrs/day while characterizing the rats lung tissue physiologies and clinical markers of over exposures. Primary observations reported included lung inflammation and tissue necrosis in the phytol dosed rats after only 1-2 days of treatment. Morbidity rates after 4 hours of aerosol phytol nasal inhalation much exceeded in severity compared to the mild adverse effects observed of the PG treated group where the rats mainly recovered to regularities after doses delivered.
Click on the link access the full research article. https://www.tandfonline.com/doi/full/10.1080/08958378.2020.1867260
Extracts and vape products containing phytol are limited to very few New Cannabis Product submissions and contain less than 2%. However, phytol is a chemical condensation precursor to α-tocopherol (Vitamin E) acetate - a known concern for e-Cigarette liquids as recent study focuses for the US FDA in combinations with THC formulations (Lanzarotta et al, Analytical Chemistry Feb 2020). Follow on research by the Center for Disease Control observed toxic chemicals produced by the thermal decomposition of vitamin E acetate (VEA) and the link to acute lung illness in adult-use cases. For example, the formation of VEA-THC complexes that co-carry to the lungs has been investigated and may present a similar interaction of concern for phytol formulations.
Health Canada confirms that no adverse reaction reports have been filed from the known registered phytol containing products on the market. The agency continues to support open consultation and decisions for voluntary stop-sale actions should new information come to light.
Future work examining the molecular compositions of vape combustions and lung distress symptoms from real-world scenarios, in daily moderate use settings, is how the industry can interpret the scientific research and discriminate potential risks in cannabis product development agendas with consumer safety top of mind.