Trace analysis of Homo Sapiens teeth by using Laser Induced Breakdown Spectroscopy.

G. M. BILMES; F. C. ALVIRA; F. RAMÍREZ ROZZI

Montreal, Canada

Congreso; 4th International Conference on Laser Induced Plasma Spectroscopy and Applications; 2006

Institut National de la Recherche Scientifique

One of the main data retrieving pieces in anthropology are teeth and bones. Identification of trace elements in their composition allows obtaining valuable information about alimentary habits and community life conditions of groups and individuals. Conventional methods for trace concentration determination require sample preparation, with partial or total destruction of the pieces which in most cases are unique. In this work, we show how Laser Induced Breakdown Spectroscopy (LIBS) is an option for this type of studies. We applied this technique to the determination of strontium and magnesium traces in Neolithic, Middle Age, and nowadays teeth of Homo-Sapiens. Dentine and Enamel of the samples were studied. In most of the cases nanosecond single pulse analysis was sufficient to perform trace identification, taking advantage of the real-time, cuasi-non destructive possibility of LIBS. Pulse by pulse in-depth analysis where also performed as well as the measurement of Mg/Ca and Sr/Ca rations for different regions of the teeth, allowing to analyzed the heterogeneity of the trace elements through the growing lines. We found also important differences in the Mg/Ca and Sr/Ca rations in dentine and enamel between the three groups of hominids, result that can be attributed to different feed habits.