Elemental mapping in fossil tooth root section of Ursus arctos by laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS)

• Published in: Talanta (Oxford) Vol. 105; pp. 235 - 243
• Main Authors: Vašinová Galiová, M., Nývltová Fišáková, M., Kynický, J., Prokeš, L., Neff, H., Mason, A.Z., Gadas, P., Košler, J., Kanický, V.
• Format: Journal Article
• Language: English
• Published: Netherlands Elsevier B.V 15-02-2013
• Subjects: Animals; Diagenesis; Diet; Fossils; Geochemical analysis; Laser ablation ICP-MS; Lasers; Mass Spectrometry - methods; Migration; Ursidae - anatomy & histology; Geochemical analysis; Diagenesis; Diet; Migration; Laser ablation ICP-MS
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2012.12.037

Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to map the matrix (Ca, P) and trace (Ba, Sr, Zn) elements in the root section of a fossilized brown bear (Ursus arctos) tooth. Multielemental analysis was performed on a (2.5×1.5)cm2 area. For elemental distribution, a UP 213 laser ablation system was coupled either with a quadrupole or a time of flight ICP-MS. The cementum and dentine on the slice of the sample surface were clearly distinguishable, especially changes in elemental distribution in the summer and winter bands in the fossil root dentine. Migration and diet of U. arctos were determined on the basis of fluctuations in Sr/Zn ratio and their contents. Quantification was accomplished with standard reference material of bone meal (NIST 1486) and by the use of electron microprobe analysis (EMPA). Changes in Sr/Zn and Sr/Ba ratios relating to the season, and composition of food during the lifetime of the animal are discussed on basis of analysis of light stable isotopes. It was observed that there was an increase in the Sr/Zn ratio during the winter season caused by a reduction of food intake during hibernation. Above mentioned inferences drawn from elemental data obtained by LA-ICP-MS were confirmed independently by determination of carbon, nitrogen and strontium isotopes. Moreover, diagenesis and its interfering influence on the biogenic composition of cementum and dentine were resolved. According to the distribution and/or content of the element of interest, post-mortem alterations were revealed. Namely, U, Na, Fe, Mg and F predicate about the suitability of the selected area for determination of migration and diet.
► LA-ICP-MS elemental mapping with quadrupole and time of flight analyzers. ► Spatial resolution of seasonal bands in fossilized biominerals of animal tooth. ► Migration and diet of the animal during its lifetime can be described. ► Determination of the part of the fossil finding influenced by diagenesis. ► Study of fossilized samples without sample chemical cleaning prior to analysis.