Age estimation of archaeological remains using amino acid racemization in dental enamel: A comparison of morphological, biochemical, and known ages-at-death

• Published in: American journal of physical anthropology Vol. 140; no. 2; pp. 244 - 252
• Main Authors: Griffin, R.C., Chamberlain, A.T., Hotz, G., Penkman, K.E.H., Collins, M.J.
• Format: Journal Article
• Language: English
• Published: Hoboken Wiley Subscription Services, Inc., A Wiley Company 01.10.2009; Wiley-Liss
• Subjects: 19th century; Age; Age Determination by Teeth - methods; age-at-death; amino acid composition; Amino Acids - chemistry; Anthropological methodology; Anthropological methods; Comparative analysis; Death; Dental Enamel - anatomy & histology; Dental Enamel - chemistry; Dental Enamel Proteins - chemistry; diagenesis; England; Excavation and methods; Human paleontology; Human remains; Humans; Laboratory methods; Mankind origin and evolution; Methodology and general studies; Middle Ages; Morphology; Physical and chemical analysis; Physical anthropology; Postmortem Changes; Prehistory and protohistory; United Kingdom; Switzerland; Great Britain; Europe; diagenesis; Chemical analysis; Demography; Enamel; Method; Physical anthropology; Necropolis; amino acid composition; Amino Acid Racemization; Comparison; Tooth; age-at-death; Human remain; Age at death
• ISSN: 0002-9483; 1096-8644
• DOI: 10.1002/ajpa.21058

The poor accuracy of most current methods for estimating age‐at‐death in adult human skeletal remains is among the key problems facing palaeodemography. In forensic science, this problem has been solved for unburnt remains by the development of a chemical method for age estimation, using amino acid racemization in collagen extracted from dentine. Previous application of racemization methods to archaeological material has proven problematic. This study presents the application to archaeological human remains of a new age estimation method utilizing amino acid racemization in a potentially closed system—the dental enamel. The amino acid composition and extent of racemization in enamel from two Medieval cemeteries (Newcastle Blackgate and Grantham, England) and from a documented age‐at‐death sample from a 19th century cemetery (Spitalfriedhof St Johann, Switzerland) were determined. Alterations in the amino acid composition were detected in all populations, indicating that diagenetic change had taken place. However, in the Medieval populations, these changes did not appear to have substantially affected the relationship between racemization and age‐at‐death, with a strong relationship being retained between aspartic acid racemization and the morphological age estimates. In contrast, there was a poor relationship between racemization and age in the post‐medieval documented age‐at‐death population from Switzerland. This appears to be due to leaching of amino acids post‐mortem, indicating that enamel is not functioning as a perfectly closed system. Isolation of amino acids from a fraction of enamel which is less susceptible to leaching may improve the success of amino acid racemization for archaeological age estimation. Am J Phys Anthropol, 2009. © 2009 Wiley‐Liss, Inc.