Archaeological and Anthropological Sciences

, Volume 11, Issue 7, pp 3357–3374 | Cite as

How bone degradation, age, and collagen extraction methods affect stable isotope analysis

  • N. HokeEmail author
  • A. Rott
  • S. Johler
  • A. Reul
  • A. Beck
  • A. Günther
  • R. Hochleitner
  • M. Kaliwoda
  • M. Harbeck
Original Paper


Stable isotope analysis from bone collagen and carbonate is a crucial tool in archaeometry for dietary and provenance studies. However, an expedient evaluation and interpretation of results have to rely on the integrity of the isotopic values, reflecting the in vivo signal of the tissue. In this context, postmortem bone breakdown can affect measurement results and add uncertainty. This study investigates the effects of bone breakdown and the use of two different extraction methods on the isotopic composition of carbon, nitrogen, and oxygen from collagen and the structural carbonate. The main goal of this study was to test the efficiency of commonly applied quality markers to identify alterations of the isotopic in vivo signal in the organic and inorganic bone fraction. Three fresh human femur diaphyses from different age groups with a known in vivo signal were degraded experimentally to simulate diagenetic processes. One batch was heated in water to induce hydrolytic breakdown; the other one was inoculated with several aerobic and anaerobic bacterial strains for biodeterioration. Furthermore, 60 long-bone samples from natural burial conditions, representing different age groups and burial times, were analyzed. The collagen extraction method proved to have a relevant effect. For bones already compromised by degradational processes, the common gelatin extraction protocol using pulverized bone and a 1 M HCl demineralization step was shown to be too harsh and damaging to the extract. Additionally, the age of the individual might play a role in the resistance of the tissue against degradational factors. The investigation of the commonly used quality criteria revealed that the C/N molar ratio is well suited to identify diagenetically modified isotopic data from collagen carbon and nitrogen. However, no valid marker could be assessed for the reliable prediction of altered δ18O values from the structural carbonate fraction, but oxygen isotopic values proved to be considerably affected by in vitro degradation.


Experimental bone degradation Quality criteria Stable isotope analysis Collagen extraction C/N molar ratio 



We would like to express our gratitude towards Dr. Christian Braun of the Department of Legal Medicine, LMU Munich, for providing access to the tissue donations, as well as to the administration and staff of the cemetery Munich West. Furthermore, we would like to thank Florian Wagner of the Helmholtz Institute Munich for the generous help with the gamma inactivation of the microbially inoculated specimens. We would also like to thank the work group of Prof. Dr. Grupe, Department Biology I, Anthropology, LMU Munich, for providing lab space and equipment. In particular, we would like to mention Prof. Dr. Karl Thomas Fehr, Department of Earth and Environmental Sciences, LMU Munich, for his fruitful contribution to the research project and his motivation and ideas. He passed away unexpectedly on March 18, 2014, leaving a big gap not only in the scientific community.

Funding information

This study was funded by a research grant from the German Science Foundation (DFG, HA5979).

Supplementary material

12520_2018_765_MOESM1_ESM.pdf (1.6 mb)
ESM 1 (PDF 1629 kb)


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Copyright information

© Springer-Verlag GmbH Germany, part of Springer Nature 2018

Authors and Affiliations

  • N. Hoke
    • 1
    Email author
  • A. Rott
    • 1
  • S. Johler
    • 2
  • A. Reul
    • 3
  • A. Beck
    • 3
  • A. Günther
    • 3
  • R. Hochleitner
    • 4
  • M. Kaliwoda
    • 4
  • M. Harbeck
    • 1
  1. 1.State Collection for Anthropology and PalaeoanatomySNSBMunichGermany
  2. 2.Institute for Food Safety and HygieneUniversity of ZurichZurichSwitzerland
  3. 3.Section Mineralogy, Department for Earth and Environmental SciencesLMU MunichMunichGermany
  4. 4.Mineralogical State CollectionMunichGermany

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