Scientists Find Cannabis in Ancient Chinese Tombs

The use of plants and associated materials to alter our state of consciousness is nothing new. The use of heroin, cocaine and cannabis is a very part of modern society. But how far back does the use of mind-altering substances go? Well, according to a recent paper published in the journal Science Advances, the use of cannabis can now be traced back to at least 2500 years ago.

Although cannabis is one of the oldest cultivated plants in Asia, it was grown for grain and fibre. But in the paper -The origins of cannabis smoking: Chemical residue evidence from the first millennium BCE in the Pamirs - scientists suggest that they have uncovered some of the earliest evidence for the ritualized use of cannabis as a psychoactive compound. So, did the ancient Chinese roll a joint? Read on.

No joints or pipes to be seen here

Wild cannabis grows in many of the foothills across Central Asia to western China - but the cannabinol levels in wild plants are low, and nobody is sure when the plant was first cultivated for higher cannabinol levels meaning a higher concentration of psychoactive compounds. But, even if the crop was grown for its mind-bending properties - how did ancient people consume the drug?

When people smoke they inhale and exhale fumes - think of cigarette smoking or pipe smoking. But it is thought that smoking pipes was introduced into Eurasia from the New World. There is no clear evidence that pipes were used in Central Asia before modern times. The paper referenced above reports on findings in China that suggest people were burning cultivated cannabis in braziers before inhaling the vapours - either recreationally or in rituals.

Chromatography analyses the THC

The researchers analysed ten wooden braziers that were exhumed form tombs at Jirzankal Cemetery. The cemetery dates from around 2500 years ago and the braziers had no obvious use and were not associated with any other remains. The researchers extracted organic material from the braziers and analysed it using gas chromatography-mass spectrometry. The use of GC-MS is discussed in the article, Rapid Determination of Strawberry Flavour Integrity using Static Headspace-Selected Ion Flow Tube Mass Spectrometry.

The analysis of the cannabis found on the braziers suggests that the cannabis used was cultivated rather than wild cannabis. This is due to the higher levels of psychoactive compounds in the residues compared to wild cannabis. The burning of the cannabis suggests that fire was an important part of funerary rites at the cemetery, particularly for local people - excavations at the cemetery and isotopic analysis suggests it was local people who had braziers during their funeral. The authors state: ‘Ultimately, this study illustrates that the earliest targeted use of cannabis with higher levels of THC originated in western China or the broader Central Asia region’.