Evidence suggests that humans may have been using cannabis for its psychoactive effects as early as 2,800 years ago, according to a new study published in the journal Science. Archaeologists excavating a monumental tomb in Siberia's Uyuk Valley discovered cannabis seeds alongside preserved human hair, offering the earliest known indication of the plant's use for mind-altering purposes.
The findings predate previously known use of cannabis in neighboring China by at least 300 years. The research team, comprised of experts from Germany, Russia, Sweden, and Switzerland, analyzed residues in the hair found at the Tunnug 1 site, which is associated with the Scythians, ancient nomadic peoples of Central Asia and southern Russia.
"It's extremely rare that we have both preserved plant parts and human soft tissue with the active compounds in it in the same context," said Gino Caspari, an archaeologist at the University of Bern and co-author of the study. He noted that while the method of consumption—whether inhalation or ingestion—is unclear, the presence of both cannabis seeds and human hair in the tomb indicates a significant role for the plant within the community.
Radiocarbon dating of the more than 1,000 discovered seeds placed their origin around 800 BC. The seeds were found deposited within the tomb, suggesting they were not accidental inclusions but had ritualistic or practical significance.
Some experts have raised questions about the study's methodology. Volker Auwaerter, head of the forensic toxicology section at the University Medical Center in Freiburg, Germany, expressed skepticism, stating that the hair analysis was "scientifically weak" and insufficient to definitively conclude cannabis consumption for psychoactive purposes. He pointed out that the presence of cannabis could be due to external exposure rather than ingestion or inhalation, as the plant also has non-psychoactive uses like oil production and fiber for textiles.
However, Elisa Guerra Doce, a researcher at the University of Valladolid in Spain who specializes in prehistoric use of consciousness-altering substances, supported the study's findings. She stated that toxicological hair analysis is a recognized method in archaeology for identifying the consumption of psychoactive substances and credited the authors for demonstrating that cannabis was likely consumed by individuals associated with the burial rite, rather than merely being a funerary offering.