Human hair containing traces of THC and more than 1,400 cannabis seeds found in a 2,800-year-old Siberian tomb provide the oldest directly dated evidence of cannabis being used for its intoxicating effects. The discovery links cannabis to Scythian funerary practices and offers a rare glimpse into how the plant may have been used in ancient Eurasia.
We’ve said it before, we’ll say it again: people have been doing drugs forever. There’s little wishful thinking behind this statement—it’s very much backed by science. Just a few weeks ago, researchers found some of the earliest evidence of drug use in 25,000-year-old human teeth from Indonesia, though this is far from the only case scientists have uncovered. Now, we’ve encountered another archaeological milestone.
As reported by CNN, researchers have found human hair with traces of THC along with cannabis seeds in a Siberian tomb, dating back almost 3,000 years. While we know humans have used the plant for thousands of years, this is now the oldest directly dated evidence of cannabis being used for its intoxicating effects.
The Oldest Direct Evidence of Psychoactive Cannabis Use

We’ve known that cannabis has been deliberately grown for at least 4,000 years (with some sources putting the figure at 6,000), with early cultivation documented in East Asia. We know its seeds and fibers were used for textiles, food, oils and medicine… but how long have humans known and enjoyed the high?
This new study, published in Science, acknowledges that, while we have plenty of evidence that marijuana has long been used for ritual purposes—just check out these 2,500-year-old “bongs” found at an ancient Chinese cemetery—evidence of its psychoactive use has been severely lacking. This is due, in part, to the fact that “surviving plant remains which are almost 3,000 years old are extremely rare,” as lead author Gino Caspari told CNN. “It is even rarer to find them in combination with human soft tissue like hair.”
This hair was the key piece of evidence: when tested, it showed traces of THC (the psychoactive compound in weed responsible for the high) and CBN. So these findings provide the earliest directly dated evidence of cannabis being used for its intoxicating effects, although the researchers cannot determine exactly how it was consumed. There is some scientific debate about whether environmental exposure can lead to positive hair tests, but it would be far from the first time toxicological hair analysis has been used to identify drug exposure.
So who was this person? The remains were found in a monumental elite tomb in the Uyuk Valley in southern Siberia. This was the burial place of several high-ranking people belonging to the earliest Scythian period. Scythians were nomadic horseback riders who dominated the Eurasian Steppe in the 8th century BC and eventually expanded to modern-day southern Russia. And this is not the first time the Scythians have been associated with marijuana: ancient Greek historian Herodotus described Scythians growing hemp and enjoying its effects a whole 2,500 years ago.
“The seeds show that cannabis played an important role in the rituals surrounding the burial,” said Caspari according to the Max Planck Institute of Geoanthropology—although the evidence doesn’t show whether cannabis was specifically grown or selected for higher levels of active compounds. What we do know is that the seeds were found within a broader funerary context: researchers also documented extensive horse sacrifices and scattered human remains that may point to human sacrifice, although the latter interpretation remains uncertain.

As for the plant remains, scientists found more than 1,400 seeds, whose DNA is now being sequenced by the research team. “Having well-preserved plant DNA is even rarer than having plant remains and this is the oldest preserved cannabis DNA,” Caspari told CNN.
Caspari, a researcher at the University of Bern’s Institute of Archaeological Sciences and the Max Planck Institute of Geoanthropology, also said that “we think this provides a cultural anchor point for current debates on legalization and medical use of the plant.” Nearly 3,000 years later, the discovery adds another piece to the puzzle of humanity’s long and complicated relationship with cannabis.
Cover: Russischer Photograph um 1900, Public domain, via Wikimedia Commons


















