HHC - Hazardous substances in vapes, hashish and cannabis flowers
For some months now, hexahydrocannabinol (HHC) has been offered in various European countries as a legal alternative to ∆9-THC products. The substance is available sprayed on flowers, incorporated into hashish and edibles, or as e-liquids and vapes.
HHC is a THC derivative that occurs only in trace amounts in the cannabis plant. It is therefore primarily obtained by hydrogenation of THC (for example, from cannabis extracts), but can also be produced fully synthetically. Studies from the early 1940s indicate that HHC is about half as potent as ∆9-THC, but otherwise has similar effects. According to user reports, the spectrum of effects is similar to that of ∆9-THC, but in higher doses, the substance is said to have an effect that is perceived as unpleasant. Little is known about the risks and side effects of HHC, and there are no data on the long-term effects of its use.
HHC is called a semi-synthetic cannabinoid because, unlike synthetic cannabinoids, it can be obtained by chemical conversion of natural cannabinoids. With this substance class of semi-synthetic cannabinoids, to which for example also ∆8-THC belongs, a wide field of potential successor substances opens up, similar to the synthetic cannabinoids mentioned above, all with unknown risk potential.
HHC is, as with synthetic cannabinoids, applied to CBD flowers or added to e-liquids and vapes and consumed that way. Contrary to what many stores suggest, there are no known cannabis plants that naturally contain enough HHC to produce a high.
In parallel, various online stores advertise HHC-O, which is described as more potent and is supposed to have a similar effect as ∆9-THC and thus stronger than HHC. This substance carries additional health risks, which are explained below.
After several medical emergencies and some deaths related to THC-containing vapes in the U.S. in late 2019 / early 2020, a study proved that a substance called vitamin E acetate was responsible. When such acetates are heated, the toxic compound ketene is formed, which can lead to respiratory problems and lung failure.
A recent study from the USA shows that the same problem is also to be expected in the case of other acetates, such as ∆9-THC-O, ∆8-THC-O and HHC-O. These substances also decompose under strong heating with the formation of the mentioned ketene. Thus, the consumption of these products implies a high health risk.
What's new in connection with HHC is that cannabis flowers, hashish and edibles containing HHC-O and other acetates are also being offered. Thus, when consuming these products, one additionally assumes the above-mentioned health risk.
Products containing HHC-O are also currently appearing in Switzerland. It is doubtful that consumers are aware of the active ingredients and mixtures contained in the products consumed and what their risks are. In general, vapes and e-liquids that contain other pharmacologically active substances (such as synthetic cannabinoids in CBD vapes or HHC-O in HHC vapes) in addition to or instead of the declared ingredients are appearing again and again.
In addition to the possible risk of choosing HHC-O or other acetates for products that are sold as more potent and "better" than HHC itself, there is also the risk that products may nevertheless contain HHC-O or other acetates contrary to the declaration.
This article was produced in collaboration with the Forensic Institute Zurich (FOR).
