Indigenous communities in the western regions of South America have ingested coca leaves for both medicinal and recreational purposes for thousands of years. It wasn’t until the 19th century that Western chemists developed cocaine hydrochloride, popularizing the plant throughout Europe. But thanks to new forensic analysis, at least a few people knew about (and embraced) the effects of coca as much as 200 years earlier than originally thought.
The evidence is detailed in a study published in the Journal of Archaeological Sciences by medical and biomedical specialists at the University of Milan and the IRCCS Ca’ Granda Foundation. According to the team, at least two preserved brains buried in a crypt at a 17th-century hospital show evidence of the coca plant’s active compounds: cocaine, benzoylecgonine, and hygrine. These chemicals, particularly hygrine, indicate that the pair of late Renaissance locals chewed the leaves or drank a tea containing coca shortly before their death and burial at Ospedale Maggiore.
(Related: Sharks test positive for cocaine.)
One of Italy’s most famous hospitals at the time, Ospedale Maggiore, operated in Milan for most of the 17th century. Nearly a century of medical care also meant many deceased patients, which required the construction and maintenance of an increasingly large crypt close to the medical facility. As the study’s authors explain, this ultimately resulted in an archaeological treasure trove that now contains an estimated 2.9 million bones from around 10,000 people.
The recovery and study of these remains continues to expand experts’ knowledge of the late Renaissance and early modern period. In 2023, for example, mummified brain and bone samples tested positive for opium use due to the presence of Papaver somniferum (poppy seed), as well as hemp—the last of which was not documented at the time.
Coca was another plant thought to be unknown in Italy until the 19th century, when pharmacists first began to synthesize cocaine hydrochloride salts. However, after an examination of the mummified brain matter of two people buried at Ca’ Granda, that story has had to be revised somewhat.
“(W)e present, to our knowledge, the first hard evidence regarding the use of the coca plant in Europe through archaeotoxicological analyses on human remains in the extraordinary context of the Ca’ Granda crypt, which allows its use in Europe to be dated back to the 1600s,” the authors write in the conclusion of their article.
This realization doesn’t come entirely out of the blue. As the researchers note in their study, historical written evidence suggests that Spanish sailors were at least aware of the effects of the coca plant after arriving in South America. At the same time, Europeans quickly became increasingly interested in “exotic plants… in the New World” as knowledge spread throughout the continent. Between the 16th and 17th centuries, maritime trade expanded between South America and Milan, then under Spanish rule. According to the researchers, this “shows a direct connection between the Italian city and the continent of origin of the plant.” That “direct connection” can now be traced directly to the 17th-century Ca’ Granda crypt, even though local pharmacological records don’t mention coca or cocaine for another 200 years.
Beyond the chemical trail, the study authors currently don’t know much about how popular coca leaves were at the time, or whether they were used more for medicine or recreation. However, given both the location and method of burial, experts believe the two bodies belonged to poorer people. With this knowledge, it’s also possible that struggling, hungry locals turned to coca leaves for their appetite suppressant side effectsIf so, the team suggests that coca leaves may not only have been present in Milan two centuries earlier than once thought, but that the plant was also cheap, popular and widespread.
