There are analytical standards for the thiols in cannabis. There are 2-3 main ones that show up but there are about a dozen different documented thiols in the plant. You just won’t see them in flower because they occur below 0.001%. Humans pick up on thiols at as little as 10 parts per billion so you could add some more zeros in there and it’d still affect the smell. You just need to test cannabis essential oils (terpenes) directly to be able to see them. A few of the same thiols you see in cannabis are in tons of fruits, vegetables, nuts, beer, wine, skunk butts. Etc
That’s not to say there are aren’t any we don’t know about yet. Given the highly reactive nature of the multiple thiols we do know about, there’s basically no way there aren’t other thiols/thiol derivatives in cannabis.
In the 80’s the DEA decided to spray pesticides on Mexican cartel crops from helicopters. Knowing contaminated crops would still be sold on the black market anyway, they decided to add an unpleasant smelling odorant to the pesticide to warn people it’s contaminated.
What did they pick to serve as a marker it’s dangerous to smoke? Only the loudest and skunkiest class of chemicals in the cannabis plant— Thiols. They encapsulated a Thiol derived from d-limonene so it wouldn’t stink up the choppers and dumped a bunch of skunky funk terps all over cartel crops to “deter” people from using it. They took the one plant that is considered more desirable when it smells skunky and made it even more skunky— to make people not want it.
Yeah I think they would have been more successful if they added artificial cotton candy flavoring or something that cannabis users don’t like. Making it skunkier makes me feel like buyers would have assumed it was just some really loud Mexican cannabis.
Here’s a news article from 1979 that covered it. They said it would smell like “skunk essence” and “poo-poo [sic].” I’m sitting here thinking about strains like Skunk 1 and Dogshit respectively and wondering if they really were trying to deter people from using it or just make it more desirable and easier to track its origin with an encapsulated marker chemical.
Chimera just posted this paper on IG that talks about the production of Thiols in Cannabis. Specifically methyl-2-butene-1-thiol was called out as being the primary odorant. Paper and supplemental graphs are attached
.acsomega.1c04196.pdf (3.4 MB) ao1c04196_si_001.pdf (4.1 MB)
Crazy how it’s the year 2021 and we are just now identifying the skunk odor compounds in cannabis! Very cool work by the Abstrax team. Somehow I never noticed this thread, but I too always had the hunch many of the odor compounds were sulfur containing. You can certainly smell it when distilling material that was not treated with exogenous sulfur.
