Forensic Toxicology Reveals Drug Exposure in 500-Year-Old Inca Child Mummies
A new forensic toxicology study reveals traces of cocaine and other psychoactive substances in 500-year-old Inca child mummies, offering clues to ancient rituals.
Chemical traces preserved in the hair and fingernails of eight Inca child mummies have revealed new evidence of psychoactive substance use during ancient sacrificial ceremonies in the Andes.
The research, published online in the journal Antiquity on November 3, 2026, was reported by Smithsonian Magazine on November 4. The study examined remains recovered from high-altitude sites in Peru and Argentina, dating back approximately 500 years.
Led by Dagmara Socha of the University of Warsaw, researchers analysed samples from eight individuals using liquid chromatography-tandem mass spectrometry, a sensitive technique capable of detecting small quantities of chemical substances.
The analysis identified cocaine and its metabolite benzoylecgonine in all eight individuals' hair samples, providing evidence consistent with coca consumption.
Researchers also detected cocaethylene in two individuals. This compound forms when cocaine and alcohol are present together in the body, suggesting combined exposure.
In another case, the fingernails of a mummy recovered from Mount Ampato contained harmine, a psychoactive alkaloid associated with plants used in traditional ayahuasca preparations.
The findings suggest that psychoactive substance use varied between individuals and ceremonial locations.
Hair and nails are particularly valuable in forensic toxicology because chemicals and their metabolites can become incorporated into keratin as these tissues grow, preserving evidence of earlier exposure.
This allows researchers to investigate substance-use patterns long after death, including in archaeological remains.
However, detecting a compound does not establish the exact dose, the circumstances of administration, or an individual's emotional state.
The small sample also limits conclusions about practices throughout the Inca Empire.
The study demonstrates how modern forensic toxicology can reconstruct aspects of ancient human behaviour while distinguishing measurable chemical evidence from historical interpretation.