A recent study led by Dr.Elena Fiorin and published in the Journal of Archaeological Science investigated the use of mercury-based treatments for leprosy in the late medieval period.

Unlike previous research that focused on bones, this study analyzed dental calculus, or hardened plaque, from individuals buried in leprosaria cemeteries in England and France.

Researchers found elevated mercury levels in these individuals, suggesting that mercury treatments were applied during their lifetime rather than being the result of environmental contamination.

The study analyzed 76 individuals and 45 soil samples, showing that mercury was present in the bodies but not in surrounding soils, ruling out external sources.

Variations in mercury levels among individuals may reflect clinical severity, access to treatment, or social status, as those buried in the leprosarium chapel exhibited higher levels, indicating privileged access to medical care.

This research demonstrates that dental calculus is a valuable tool for detecting historical medicinal practices and offers a new method for studying ancient healthcare strategies beyond bones and hair.Future studies aim to determine when mercury treatments began by comparing skeletons with and without leprosy symptoms in these institutions.