Weed joint
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The Chemistry Behind Marijuana’s Skunky Scent

Odiferous compounds create the plant’s distinctive scent—and in some strains, growers are experimenting with new combinations to create unexpected aromas.
By Brittany Dennison
April 20, 2022
4 minute read

The smell of marijuana has long been demonized as “skunky”—linking the typically negative connotations of being high with the indelible disaster that is sprayed from a skunk’s behind. Skunkiness has no pleasant olfactory associations; it’s described as smelling like rotten eggs, burnt rubber, and farts. It’s no wonder that, for many years, to be accused of smelling like a pothead was a grave insult.

Making connections between the aromas of marijuana and skunk spray is justifiable, as the two are chemically related: Research has found evidence of volatile sulfur compounds, or VSCs, in both. And recently, scientists discovered a new family of VSCs in cannabis that create its signature smell. But tetrahydrocannabinol (THC), the principal psychoactive component of cannabis, is odorless; many weed smokers associate stronger-smelling marijuana with a higher potency, when in fact there’s no correlation whatsoever. Some strains just happen to have higher concentrations of VSCs—and some of those compounds, such as 3-methyl-2-butene-1-thiol (VSC3), make for extra-skunky strains. (This compound is also found in skunked beer, brews that have been compromised following exposure to ultraviolet or artificial light.)

These days, certain marijuana strains produce smells far beyond skunkiness when smoked. That’s because their growers have been experimenting with another odoriferous compound, terpenes, that are responsible for the scent of a plant, which produces them to attract pollinators or protect against predators. Research suggests that individual terpenes can aid well-being, with benefits such as decreasing anxiety or increasing alertness, though little is known about how the compounds work together or in combination with THC, cannabidiol (CBD), and other cannabinoids. More than 140 different terpenes have been identified in cannabis to date, and lately, some manufacturers have started generating their own terpene profiles that, in addition to providing added health advantages, enhance the terpenes naturally found in the plant’s flowers with more-enticing scents. These strains mimic all kinds of delicious aromas, including the citrusy Lemon Kush, enhanced with limonene, a terpene found in lemons and known for its mood-elevating and antibacterial properties; and Blue Dream, which is high in myrcene, a terpene celebrated for its relaxing effects, and smells like a blueberry pie.

Innovations aside, the base notes of marijuana’s distinct smell endure—and the reaction to them depends on the nose. For me, to smell like weed is to smell of more than just the plant, but also of the communal act of smoking. It’s also to smell of ash, like the burnt paper and sulfuric spent match used to light a joint. Weed smells friendly, akin to a cloud of smoke, and to herbaceous, sun-warmed grass, which beckons like a lighthouse in a party of strangers. Consider its scent long enough, and you can detect something slightly fruity, like the bowl of Fruity Pebbles one might inhale while watching movies on a lazy Sunday morning. The website Fragrantica, a comprehensive encyclopedia of perfumes, currently lists hundreds of fragrances with cannabis notes, signaling that mainstream connotations of weed’s smell are changing. Gone are the days of dousing oneself with body spray to cover up the plant’s musky aroma. Now, one can now be lemony, spicy, sweet—and even skunky—with pride.