Hair and Nails of Inca Sacrifice Mummies Reveal Cocaine, Alcohol and an Ayahuasca Compound

Archaeologists have identified the psychoactive substances consumed by people sacrificed at Inca mountain shrines, finding that the drugs differed from one individual and one mountain to the next.

The ritual was the capacocha, one of the most sacred ceremonies in the Inca Empire. Children and young women were sacrificed as an act of veneration for important deities, becoming intermediaries between the living and the divine. They were often given psychoactive substances, possibly as a way to enhance their prophetic abilities. Historical accounts record the Incas' use of such plants, but little was known about what was consumed during the capacocha itself.

"Earlier analyses either produced negative results or focused primarily on coca leaves," said the study's lead author, Dr. Dagmara Socha of the University of Warsaw. The mummified bodies offer a rare chance to look, because chemicals become embedded in the keratin of hair and nails, where toxicology can identify them. "Recent advances in toxicology now allow for the identification of low concentrations of such substances," Socha said.

The team analyzed hair and nail samples from eight mummies recovered from several mountains in Peru and Argentina, covering a wide range of sacrificial practices across the empire. The results are published in the journal Antiquity.

In every mummy, the researchers found cocaine, confirming that all of them chewed coca leaves. Coca was central to Inca religious belief as an offering to the gods, but it could also have helped the children cope with altitude sickness and fatigue on the long, arduous climb to the summits.

In four mummies, the team found evidence of alcohol, possibly from chicha, the corn beer that historical records say was given to the children to dull their senses and calm them in the final stage of the ritual.

The most striking finding involved the Lady of Ampato, known as Juanita, a mummy found on a southern Peruvian volcano in 1995. "We detected traces of harmine," Socha said. Harmine is an alkaloid associated with Banisteriopsis plants, one of the principal ingredients of the traditional ayahuasca drink. It may indicate that a harmine-containing beverage had a specific role in ceremonies tied to that sacred mountain.

Because the combinations of substances differed between individuals, the authors conclude the capacocha was not one standardized rite. Ritual practices appear to have been adapted to local religious traditions and to the particular deities or sacred places involved, which suggests the empire's central religion left room for regional variation.

"Five hundred years after these children were sacrificed during one of the most important Inca rituals, new technologies are allowing us to uncover details of their lives and Inca religious practices," Socha said. The sample is small, just eight individuals, so the patterns will need testing against more remains. The study is titled "Toxicological studies on the Inca frozen mummies from volcanoes in Peru and Argentina."