Elo Joandi (in the picture on the right), a gymnasium student of the Miina Härma Gymnasium, won the first prize at the Estonian Research Council’s contest for student research. Congratulations to Elo and her supervisors!
In her work “Identifying diet based on hair isotopic analysis: a case study of modern and archaeological material” Elo studied the dietary habits of present and past individuals through the stable isotope analysis of hair keratin.
A thorough theoretical work with the literature allowed her to conduct real experiments in our Archemy lab to analyse contemporary and archaeological hair samples. She demonstrated that the nitrogen values are clearly different for vegan and carnivorous people, and that both carbon and nitrogen isotope values change when a person changes their diet from omnivorous to that of a vegetarian one.
Elo’s work is the first of its kind at the University of Tartu, aiming to understand and develop the stable isotope analysis on hair keratin. She demonstrated that the pre-treatment has an effect on the stable isotope values, allowing a better-informed sample strategy for archaeological specimens in the future. Elo’s work is an exceptional example of bridging humanities and natural sciences in the study of cultural heritage.
The research was supervised by Holar Sepp, Helen Semilarski, and by two members of our group – Mari Tõrv and Ester Oras.
Here you can find more information about the contest and awardees (in Estonian).
An exciting collaboration between analytical chemists, archaeologists, and boat experts occurred recently!
Archemy research group investigated the composition of a mysterious dark coating material from a historical boat called “Lodi”. Our PhD student Shidong used solvent extraction and gas chromatography-mass spectrometry to understand the composition of the coating.
As it turns out, the ship was covered by a mixture of coal and pine tar. Large amounts of polycyclic aromatic hydrocarbons were detected with minor quantities of abietic diterpenoids.
As a thank-you gesture, Archemy group and guests from the analytical chemistry department were invited to sail with the “Lodi” on Emajõgi. We celebrated the beginning of the academic year, looked back on our summer, and made plans for the new academic year.
From the 28th of June to the 1st of July 2022, Dr Signe Vahur, Dr Anu Teearu-Ojakäär from our UT Analytical Chemistry Cultural Heritage Investigation group, and PhD student Shidong Chen from the Archemy group attended the 5th international inArt2022 conference in Paris, France.
Anu, Shidong, and Signe
InArt is a conference where professionals from different disciplines (for example, chemistry, archaeology, conservation, biology, etc.) can present and discuss the analysis results using a limited amount of samples or non-invasive approaches and conservation strategies of cultural heritage objects. The conference included altogether 47 oral presentations and three poster sessions with 135 posters, different visit options (starting with the National Centre for Research and Restoration in French Museums (C2RMF) to a walking tour in the historical centre of Paris), and dinner at the hotel The Westin Paris.
Investigations from Fayum mummy portraits to street art
Four days were filled with a wide range of interesting presentations, from hyperspectral imaging and material instrumental analysis of different cultural heritage (paintings, sculptures, manuscripts, etc.) and archaeological objects to investigations of chemical and physical degradation mechanisms of various materials.
Some of the most interesting talks included the presentation by Prof Francesca Modugno (from the University of Pisa) about the SuPerStAr project dedicated to the studying and preservation of street art and Dr Lucile Brunel-Duverger (from French Museums Research and Restoration Center) about the analysis of madder lake dyes in the Fayum portraits (from 1st to 4th century A.D). Also should be highlighted the presentations by Dr Maria Filomena Guerra (from French Museums Research and Restoration Center) on the analysis of objects covered with gold leaf and foil from the Egyptian Middle Kindom period, Dr Laura Pagnin (from the Polytechnic University of Milan) about data fusion of Py-GC-MS and FT-IR data to determine degradation in modern paints, and also Loïc Forma (from The National Heritage Institute in Paris) who talked about how to protect cultural heritage objects from vibrational damages. There were many eye-catching poster presentations, however worth mentioning is the poster made by Dr Louise Chassouant and her colleagues on the chemical and palaeobotanical study of Roman amphorae. In their research, they developed a multidisciplinary approach (applied in archaeometry techniques) to analyse the original content of the amphorae (e.g. components of wine, oils, etc.) and determine the waterproof resin coating components in the internal surface.
The highlights of our recent results
Signe presenting her poster
Anu presenting her poster
Shidong presenting his poster
At the inArt2022 conference, we had three poster presentations from which we could present our research topics and results. Signe presented her poster “Quantitative mineralogical analysis of clay-containing materials using ATR-FT-IR-PLS method”, where an easy and quick quantitative method for determining the mineralogical composition of clays in different sizes and amounts of cultural heritage (i.e. pottery, sculptures, construction materials, etc.) samples using ATR-FT-IR spectroscopy with partial least squares (PLS) analysis is presented. Anu presented her poster „ Analysis of Early Modern Age medicine found in a shipwreck from the Baltic Sea“. In this study, ATR-FT-IR, pyGC-MS, and MALDI-FT-ICR-MS techniques were combined to determine the chemical composition of materials (like pine tar, essential oil, etc.) in the pharmacy jar found on a 16th-century shipwreck in the Baltic Sea. Shidong presented his poster “Classification of Archaeological Adhesives from Eastern Europe and Urals by ATR-FT-IR Spectroscopy and Chemometric Analysis”. This study showed that ATR-FT-IR-DA classification is a rapid and reliable pre-scanning method for analyzing archaeological adhesives (e.g. birch bark tar), which is especially suitable for small samples.
Overall, the inArt2022 conference gave our cultural heritage and archaeology objects researchers the possibility to introduce their scientific work results, hear presentations of investigation of different materials, obtain valuable tips for further research and have interesting discussions with other scientists.
Ester Oras, the PI of our Archemy research group, was awarded L’Oreal-UNESCO “For Women in Science” Young Talents Program Baltics (Estonia) with the support of the Estonian Academy of Sciences and the Estonian National Commission for UNESCO scholarship.
Ester and her team work in biomolecular archaeology and employ modern omics methods – lipidomics, proteomics, and genomics – to reveal ancient dietary practices and diseases. By analysing centuries and millennia old ceramic vessels and human remains with topnotch laboratory techniques, Ester aims to show how past foodways affected the health of ancient populations, and reveal how historically developed dietary practices influence our overall wellbeing in the past as well as today. Ester says herself: “I want to give colour and taste to the past and bring the history closer to us today.”
L’Oréal-UNESCO For Women in Science Young Talents Programme aims to support and encourage young women researchers who represent the future of science in STEM fields. The Baltic regional programme opened first in Latvia in 2004 and widened to Lithuania and Estonia in 2017, with altogether 10 Young Talents recognised from Estonia so far.
Researchers’ Night festival 2021. Superheroes of science
In English: Last week, on the 20-24 of September, Reasearchers’ Night festival 2021 took place all over Estonia. Our archaeochemist Dr. Ester Oras gave an interesting audio lecture about the eating habits of people living in the region of current Estonia in the distant past. This topic starts with the first findings related to eating habits from the Mesolithic period and arrives at the Middle Ages. During the whole lecture, she illustrates how chemical analyses can be used for the analysis of archaeological objects. Here is the audio lecture in Estonian, but there’s also a blog post in English on a similar topic.
Eestikeeles: Eelmisel nädalal (20.-24. septembril) toimus üle Eesti 16. Teadlaste Öö festival. Meie arheokeemia töögrupi juht Dr. Ester Oras andis festivali raames huvitava heliloengu, kus ta rääkis mida inimesed sõid kauges minevikus praeguse Eesti aladel. Ester selgitab inimeste toitumisharjumisi Mesoliitikumi ajajärgust (kust pärinevad esimesed toiduga seotud leiud praeguse Eesti aladel) Keskajani välja. Kogu loengu vältel kirjeldab Ester ka seda, kuidas keemilised analüüsid aitavad mõista arheoloogilisi leide. Mainitud eestikeelse heliloengu leiab siit, kuid samal teemal on olemas ka ingliskeelne blogipostitus.
In this study, 100 adhesive samples, collected from hafting tools and ceramic containers as well as some adhesive lumps were analyzed using ATR-FT-IR in combination with PCA-based DA classification. The aim of this study was to discover the capabilities of ATR-FT-IR-DA classification as a potential screening method for the identification and grouping of different archaeological adhesive samples, and subsequently reduce the use of laborious GC-MS analysis.
100 archaeological adhesives were classified into 3 groups: birch bark tar without major additives (72), birch bark tar with additives (13) and minor/non birch bark tar samples (15). Birch bark tar containing adhesives were separated from minor/non birch bark tar samples. Samples identified as birch bark tar without major additives were further classified possibly by their location, age or cultural specific manufacturing practices. The classification results were confirmed by GC-MS analysis of 9 archaeological samples selected from three compositional groups.
The study proves that ATR-FT-IR-DA classification is a non-destructive, rapid and reliable pre-scanning method for analyzing archaeological adhesives, especially suitable for small samples. Based on the results of ATR-FT-IR spectroscopic analysis, DA classification can help further distinguish samples with different backgrounds such as sample age, initial production, environmental conditions and site-specific preservation. GC-MS analysis could be used as a supplementary/confirmatory method to investigate samples with complex components and provide archaeological DA references for future research.
Archemy is the first archaeochemistry lab in the Baltics where archaeology meets with chemistry, geology, biology, medicine, genetics, material sciences, etc. Our group works in archaeological sciences, especially biomolecular archaeology, with a major focus on ancient dietary and health reconstructions, migrations, and provenance studies. Archemy has wide expertise in material culture studies, human osteology, zooarchaeology, and archaeobotany. Our lab is located at the Chair of Analytical Chemistry Ravila 14A-4011. You can read more about us and our work on our website and follow us on our Archemy lab FB page, or contact us at archemy@ut.ee.
Elo’s work is the first of its kind at the University of Tartu, aiming to understand and develop the stable isotope analysis on hair keratin. She demonstrated that the pre-treatment has an effect on the stable isotope values, allowing a better-informed sample strategy for archaeological specimens in the future. Elo’s work is an exceptional example of bridging humanities and natural sciences in the study of cultural heritage.
