Medical Treatments in Medieval Leprosaria. Exploring Healing Remedies through Dental Calculus Analysis

Project Information

MEDICAL

Grant agreement ID: 844364

DOI

10.3030/844364

Project closed

EC signature date 14 October 2019

Start date 1 March 2020

End date 31 May 2022

Funded under

• EXCELLENT SCIENCE - Marie Skłodowska-Curie Actions

Total cost

€ 171 473,28

EU contribution

€ 171 473,28

Coordinated by

UNIVERSITA DEGLI STUDI DI ROMA LA SAPIENZA
Italy

Periodic Reporting for period 1 - MEDICAL (Medical Treatments in Medieval Leprosaria. Exploring Healing Remedies through Dental Calculus Analysis)

Reporting period: 2020-03-01 to 2022-02-28

Summary of the context and overall objectives of the project

The MEDICAL project has explored the medical care offered to people who experienced leprosy and lived in two leprosaria in Northern Europe during the late medieval period through dental calculus analysis. Despite the impressive spread of leprosaria in late medieval Europe, little is known about the archaeology of these establishments, and the medical treatment of patients is usually poorly detailed by contemporary archival records or medical treatises.
Employing elemental analyses and polarised optical microscopy, dental calculus aims to be an essential source of the history of ancient medicine shedding new light on medicinal remedies used to cure the individuals hosted in medieval leprosaria.
This research is important since has been the first and -until now- the only project to investigate medical treatments offered to individuals affected by leprosy by analysing an exceptional record for the investigation of organic and inorganic substances such as plants, minerals, and animal remains: the human dental calculus.

MEDICAL aimed to 1) advance methods for interpreting ancient medicine through the study of dental calculus; 2) interpret bone changes associated with leprosy in medieval osteological collections; 3) identify ingredients employed in medicinal remedies; 4) create a comparative European overview of the medical care offered to people affected by leprosy during the medieval period.
MEDICAL has established an advanced methodology for interpreting ancient medicine by developing a protocol suitable for the preparation of tartar samples and the analysis of various trace elements, including toxic heavy metals. Thanks to the application of Inductively Coupled Plasma Mass Spectrometry (ICP-MS) and Cold Vapour Atomic Fluorescence Spectroscopy (CV-AFS), it was possible to measure chemical element concentrations using a minimal amount of dental calculus. Analysis of bone changes associated with leprosy was carried out on the osteological collection of St Leonard in Peterborough stored at Durham University (England) and St. Thomas d’Aizier at the Centre Michel de Boüard in Caen (France). The identification of ingredients employed in medicinal remedies was achieved by applying polarised optical microscopy at the DANTE laboratory, Department of Oral and Maxillo Facial Sciences, Sapienza University of Rome, and chemical analyses at the Analytical, Environmental & Geo-Chemistry Research Unit, Department of Chemistry, Vrije Universiteit Brussel (Belgium). The results obtained in the analysed leprosaria, were cross-referenced with other anthropological data, and contrasted between the two sites of St Leonard and St Thomas thus allowing a preliminary comparative overview of the medical care offered to people affected by leprosy in medieval Europe.

Due to the slowing down caused to data collection by COVID-19, some analyses are still underway. Nevertheless, some results are very promising: for instance, polarised optical microscopy analysis allowed to identify starch grains compatibles with those of ginger in some individuals from the St Leonard cemetery. In fact, ginger was mentioned by written sources among the medical ingredients employed to cure leprosy. Also, the analysis applied to detect and measure mercury concentrations proved successful in investigating the use of such a toxic metal to cure medieval individuals affected by leprosy. Preliminary results show that mercury concentrations are sensibly higher in individuals from St Leonard and St Thomas compared to the project’s benchmark population unearthed in a typical cemetery not related to a leprosy house. Applying optical microscopy and chemical analysis, we demonstrate that new and precious information can be added to this field of research. Nevertheless, more work is needed to study post-mortem contaminations and the limit in identifying the microfossils embedded in the calculus matrix.

Work performed from the beginning of the project to the end of the period covered by the report and main results achieved so far

MEDICAL focused on the human remains unearthed in the cemeteries of two medieval leprosaria in northern Europe: St. Leonard in Peterborough (England) and St. Thomas d’Aizier (France). Before starting the analyses of dental calculus, a literature survey was performed to collect data about leprosy within the European archaeological context, and medical treatments offered to people who experienced leprosy during the medieval period. In addition, thanks to a collaboration with the Botanical Garden of Rome, a modern reference collection of medicinal plants was created. Tartar samples were studied by applying polarised optical microscopy at Department of Oral and Maxillo Facial Sciences, Sapienza University of Rome, and chemical analyses at Department of Chemistry, Vrije Universiteit Brussel (Belgium). In addition, in some individuals of St Leonard, aDNA (University of Tor Vergata, Italy) and Proteomics (University of Nottingham, England) analyses were performed. Thanks to the application of several techniques, we were able to identify medicinal remedies (e.g. Ginger, mercury) and reconstruct the diet (e.g. milk, barley, fish consumption) of some individuals hosted in medieval leprosaria.
The results were presented at the International Medieval Congress in Leeds (England), at the American Association of Biological Anthropologists in Denver (Colorado, USA), and at the European Association of Archaeologists (Virtual Meeting). The project was also presented in several invited seminars at the University of Cambridge (England), Coimbra (Portugal), Caen (France), Turin (Italy) and Rome (Italy). In addition, the fellow was interviewed by the CRAHAM Centre Michel de Bouard and The International Network for the History of Hospitals (INHH) published an article about the MEDICAL project. MEDICAL was also presented to some high school classes in Italy. As part of the presentations, a questionnaire was filled out by more than 500 students. Since leprosy is still poorly known, stigmatised, and regarded with suspicion, this survey was successful in collecting data on knowledge and perception of this disease among the young generations.

Progress beyond the state of the art and expected potential impact (including the socio-economic impact and the wider societal implications of the project so far)

MEDICAL was favourably received within the research community because of its innovative and original approach designed in order to expand the knowledge of medicinal plants in archaeology. This is a topic that needs to be further explored, and MEDICAL has underlined how human dental calculus analysis is well positioned to add fresh and relevant results. Thanks to the micro-remains embedded in the tartar, we can add precious information to reconstruct the osteobiography of the individual affected by leprosy in medieval Europe. The preliminary data obtained with MEDICAL are exciting and need to be explored more in detail. The results obtained will add new information about the archaeology of the leprosaria, and the medical treatment of patients not mentioned by contemporary archival records.
Moreover, involving high school students had a very positive impact on the project. The results of the questionnaire showed that leprosy is still poorly known and thus viewed with suspicion. In addition, more work is needed to communicate the academic research to the young generations since they are not often aware of current scientific research. Young scholars can offer them an opportunity to look closer at how research is designed and developed. MEDICAL was also successful in doing this.



The project has an active website: https://medievalcalculus.com

Figure 1: Dr Fiorin sampling dental calculus for the MEDICAL project

Figure 2: Overview of the methods applied