T02_P19

Collagen extraction and amino acid purification for radiocarbon dating of a Late Neolithic mass grave

Philippsen B^1,2, Olsen J²,  Nørkjær Johannsen N³

¹Museum Lolland-Falster, Nykøbing F, Denmark, ²Aarhus AMS Centre, Department of Physics and Astronomy, Aarhus University, Aarhus, Denmark, ³School of Culture and Society - Department of Archeology and Heritage Studies, Aarhus University, Højbjerg, Denmark

The purpose of this paper is to improve the preparation of bone samples for radiocarbon dating. As a test case, we use the Late Neolithic mass grave of Koszyce, Poland.

DNA analysis of the individuals from the mass grave has demonstrated that they had been a large extended family. This supports the archaeological observation that the individuals were buried there in one single event. The mass grave thus contains bone samples of the same age and can be used to test radiocarbon sample preparation methods.

For an earlier study, we have extracted and radiocarbon dated bone collagen of fifteen human individuals and one sheep bone from the mass grave. With the traditional collagen extraction methods usually utilized at the Aarhus AMS Centre, only the sheep and three human bones yielded sufficient collagen for radiocarbon dating. We therefore modified the pretreatment procedure by using weaker reagents at lower temperatures. This enabled us to extract sufficient collagen from the remaining twelve human bone samples. However, the radiocarbon ages showed considerable spread, and several outliers had to be removed from the dataset. We therefore suspected that we had not been successful in removing all contaminants from the bone collagen and tested an alternative approach, purification of the collagen hydrolysate with an ion exchange resin.