A scientist at Rensselaer Polytechnic1 Institute and an anthropologist2(人类学家) from the University at Albany teamed up to use ultra-modern chemical analysis technology at Rensselaer to analyze3 ancient Mayan pottery4 for proof of tobacco use in the ancient culture. Dmitri Zagorevski, director of the Proteomics Core in the Center for Biotechnology and Interdisciplinary Studies (CBIS) at Rensselaer, and Jennifer Loughmiller-Newman, a doctoral candidate at the University at Albany, have discovered the first physical evidence of tobacco in a Mayan container. Their discovery represents new evidence on the ancient use of tobacco in the Mayan culture and a new method to understand the ancient roots of tobacco use in the Americas. Their research will appear in the journal Rapid Communications in Mass Spectrometry, in an article titled "The detection of nicotine5 in a Late Mayan period flask6 by GCMS and LCMS methods."
In recent years, archaeologists have begun to use chemical analysis of residues8(残渣) from ancient pottery, tools, and even mummies in an attempt to piece together minute clues about ancient civilizations. Among the potential problems with isolating9 a residue7 for analysis is preservation10 and contamination. Many vessels12 serve multiple purposes during their lives, resulting in muddled13 chemical data. Once the vessels are discarded, natural processes such as bacteria and water can destroy the surface of materials, erasing14 important evidence. Additionally, researchers must be attentive15 to archaeological field handling and laboratory treatment of the artifacts(史前古器物) that might lead to cross contamination by modern sources.
To make their discovery, the researchers had a unique research opportunity: a more than 1,300-year-old vessel11 decorated with hieroglyphics17(象形文字) that seemingly indicated the intended contents. Additionally, the interior of the vessel had not been cleaned, leaving the interior unmodified and the residue protected from contamination.
The approximately two-and-a-half-inch wide and high clay vessel bears Mayan hieroglyphics, reading "the home of his/her tobacco." The vessel, part of the large Kislak Collection housed at the Library of Congress, was made around 700 A.D. in the region of the Mirador Basin, in Southern Campeche, Mexico, during the Classic Mayan period. Tobacco use has long been associated with the Mayans, thanks to previously18 deciphered hieroglyphics and illustrations showing smoking gods and people, but physical evidence of the activity is exceptionally limited, according to the researchers.
Zagorevski used the technology within CBIS at Rensselaer, usually reserved to study modern diseases and proteins, to analyze the contents of the vessel for the chemical fingerprint19 of tobacco. The technology included gas chromatography mass spectrometry (GCMS气象色谱分析) and high-performance liquid chromatography mass spectrometry (LCMS). Both are analytical20 chemistry techniques that combine the physical separation capabilities21 of gas or liquid chromatography with the analysis capabilities of mass spectrometry. The latter is used to determine molecular22 weights of compounds, their elemental composition, and structural23 characteristics.
Zagorevski and Loughmiller-Newman's analysis of the vessel found nicotine, an important component24 of tobacco in residues scrapped25 from the container. Both techniques confirmed the presence of nicotine. In addition, three oxidation products of nicotine were also discovered. Nicotine oxidation occurs naturally as the nicotine in tobacco is exposed to air and bacteria. None of the nicotine byproducts associated with the smoking of tobacco were found in the vessel, indicating that the vessel housed unsmoked tobacco leaves (possibly powered tobacco) and was not used as an ash tray. No other evidence of nicotine has been found, at this time, in any of the other vessels in the collection.
This discovery "provides rare and unequivocal(明确的) evidence for agreement between a vessel's actual content and a specific ichnographic(平面图的) or hieroglyphic16 representation of that content (on the same vessel)," Loughmiller-Newman states in the paper. She is in the anthropology26 department at the University at Albany, studying ritual food stuff consumed by the Mayans.
Both Loughmiller-Newman and Zagorevski would like to see this technique used to analyze a greater variety of vessel types.