Use of psychoactive and stimulant plants on the south coast of Peru from the Early Intermediate to Late Intermediate Period

Abstract

The preservation of naturally mummified bodies in the Nazca drainage and Yauca Valley provided an opportunity to analyse for the first time which of the psychoactive plants were used on the southern Peruvian coast. Toxicological analysis allows us to better understand the ancient medicine, trade network and religiosity of the region of interest. Hair samples of 22 individuals (including four trophy heads) were examined using LC-MS/MS for the presence of coca alkaloids and metabolites (cocaine, benzoylecgonine, cocaethylene), mescaline, tryptamine, harmaline, and harmine. LC–MS/MS was performed using electrospray ionization (ESI) in the positive mode, multiple reaction monitoring, and a deuterated internal standard (Diazepam-D5). The limits of quantification achieved for analytes were from 1 to 5 ng/g. Recoveries ranged from 91,6 to 113,7%. The method demonstrated an intraday and interday precision CV of <15%.The results of the study show that coca leaves were present on the southern Peruvian coast since the Early Nazca Period (100 BCE - 450 CE). The Nazca inhabitants were also positive tested for the presence of harmine and harmaline coming probably form Banisteriopsis caapi (the main compound of the hallucinogenic ayahuasca beverage), and the San Pedro cactus, a source of mescaline. This is the oldest archaeological evidence of the consumption of these two plants. In modern medicine, the properties of harmine have led to its use in anti-depression and anti-addiction treatment. Banisteriopsis caapi is native to the Amazonian rainforest and had to be the object of long-distance trade, which showed its important role in ancient medicine and rituals. San Pedro cactus is taken for its strong hallucinogenic properties and was detected in hair belonging to a child victim whose head was transformed into a trophy head. This is the first proof that some of the victims transformed into trophy heads were given stimulants prior to their death.