Analysis of hair from thirty-two mummies from the Middle Period (ca. 500–1000 CE) in the Azapa Valley of northern Chile, using gas chromatography and mass spectrometry, found no traces of Anadenanthera, a plant with a long archaeological record of psychoactive use in the region. However, two mummies tested positive for Banisteriopsis, the plant used to prepare the psychoactive infusion known as Ayahuasca. The authors propose that Banisteriopsis consumption in the Azapa Valley was linked to curative and medicinal practices, such as childbirth and postpartum care, rather than to hallucinogenic rituals.
Hallucinogenic plants are often considered the main source of psychoactive drugs in antiquity for reaching deep altered states of consciousness. During the Tiwanaku empire expansion (500–1000 A.D.) along the Atacama Desert of Chile, highly decorated snuffing tablets and tubes were common grave goods, but the specific drugs consumed remained unclear. Analysis by gas chromatography and mass spectrometry of hair from naturally mummified human bodies from the modern city of Arica detected harmine in 3 of 32 samples, likely from the Banisteriopsis vine (ayahuasca). This is the first confirmed evidence of psychoactive plant consumption in pre-Hispanic Andean populations along the Atacama coastal region.