Scientists Detect 400-Year-Old Cannabis Residues in Human Bones from Milan Hospital

Researchers have identified traces of cannabis compounds within 17th-century human bones excavated from the historic Ca' Granda hospital in Milan. The study, published in the Journal of Archaeological Science, analyzed femur bones from nine individuals buried between 1638 and 1697, revealing clear evidence of THC and CBD molecules in two of the skeletons. These compounds, likely absorbed through consumption and preserved in bone tissue, demonstrate that human bones can retain a "chemical memory" of lifestyle habits for centuries.

The discovery challenges previous assumptions about the preservation of such substances in ancient remains and offers new insights into the daily lives of people from that era. Researchers examined medical records from the hospital but found no official documentation of cannabis as a prescribed treatment, suggesting its use was probably recreational or self-medicated. Alternative explanations, such as accidental exposure or private medical use outside the hospital, remain possible but unconfirmed.

This breakthrough was enabled by advanced technology that overcomes past difficulties in detecting organic compounds in archaeological bones. The findings imply that skeletal remains can serve as chemical archives, recording information about diet, substance use, and health long after death. This opens new avenues for studying historical populations and their behaviors through biochemical analysis of bones.