There’s nothing like cruising through the neighborhood and getting a good old whiff of cannabis, which quite honestly can make our mouths water. But, to non-weed smokers, this smell can be nauseating at times. 

For individuals who aren’t as affiliated with cannabis, it can be difficult to distinguish whether or not that pungent aroma is coming from cannabis or a skunk that just sprayed. A new study recently discovered what causes cannabis to emit a similar smell to a skunk’s spray. 

Interestingly, the compounds that produce the skunk-like smell in cannabis have a lot in common with a skunk’s spray. A team of researchers at California’s Abstrax Tech say that a family of prenylated volatile sulfur compounds (VSCs) are responsible for this scent.

Similarly, scientists discovered that the cannabis Sativa plant emits over 200 aroma compounds. These studies regarding the smell of cannabis are primarily focused on what’s called terpenoids or terpenes, molecules that contain vast, unique odors like fuel, wood, citrus, or floral. Each particular strain produces different combinations of these terpenes, giving them their individual and recognizable smell.

Although terpenoids contribute to most of the odor in cannabis, the study authors noted that there isn’t enough evidence to prove if terpenoids cause the skunky smell of cannabis. Because a skunk’s spray contains various VSCs, lead study author Iain Oswald and other researchers say these molecules also contribute to the smell of marijuana.

The researchers analyzed 13 different cannabis strains using a custom 2D gas chromatography system that contains three different kinds of smell detectors. Following this, a panel of four people ranked the pungency of each cannabis strain on a scale of 0 to 10. Their results found that the most pungent cannabis strain was Bacio Gelato, and it also contained the highest concentration of VSCs. 

In addition, this particular flower strain also contained seven different VSCs. The team also found other VSCs in different cannabis strains. They discovered that five of these VSCs emitted a skunk-like or sulfuric smell. One VSC, in particular, was 3-methyl-2-butene-1-thiol (or VSC3), which was the most common within the cannabis plants tested.

VSC3 is the same compound scientists have associated with the flavor and aroma of “skunked beer,” or beer that has gone bad after being exposed to UV light. The researchers also found the skunk-like VSC3 in cannabis products like concentrates, so it looks like cannabis is more related to a skunk’s spray than we thought.