Isotopic analyses tooth enamel

Tykot, R.H., van der Merwe, N.J. and Hammond, N. 1996 Stable isotope analysis of bone collagen, bone apatite, and tooth enamel in the reconstruction of human diet. A case study from Cuello, Belize. In Orna, M.V., ed., Archaeological Chemistry Organic, Inorganic, and Biochemical Analysis. ACS Symposium Series 625, Washington, DC, American Chemical Society 355-365. 

This equation predicts a value of 26.8%ofor the zebra at Turkana assuming an average value of 6%o for Lake Turkana water. This predicted value is l%o less than the actual value of 27.8%o. Given the variation in methods of sample preparation and analysis, variation between bone and tooth enamel (Stuart-Williams and Schwarcz 1997), and uncertainty in surface water oxygen isotopic composition, these values are extraordinarily close. Alternatively, if the equation is solved for using the actual value of the Turkana zebra. 

Cerling, T. and Sharp, Z. 1996 Stable carbon and oxygen isotope analysis of fossil tooth enamel... 

Evans, J.A., Chenery, C.A. and Fitzpatrick, A.P. (2006). Bronze Age childhood migration of individuals near Stonhenge, revealed by strontium and oxygen isotope tooth enamel analysis. Archaeometry 48 309-321. 

Jones, A. M., Iacumin, P., and Young, E. D. (1999). High-resolution delta 0-18 analysis of tooth enamel phosphate by isotope ratio monitoring gas chromatography mass spectrometry and ultraviolet laser fluorination. Chemical Geology 153 241-248. 

Besides the lapse-rate based methodologies, other methods have also been applied to estimate paleoelevation for Florissant. Another approach based on paleobotany has used enthalpy (Forest et al. 1995 Wolfe et al 1998), based on principles of atmospheric energy conservation, and results from this method have produced high elevation estimates (2900-3800 m) comparable to those of the local and regional lapse rate methods. Analysis of stable isotopes from mammalian tooth enamel provides preliminary results that indicate low relief and low elevation (Barton and Fricke 2006). 

Oxygen isotopes in ancient human skeletal remains are found in both bone and tooth enamel. Samples for the analysis of human skeletal remains are normally taken from dental enamel due to conditions of preservation and resistance to diagenesis. The hydroxyapatite mineral, a primary component of enamel, contains oxygen, in both phosphate groups (POp and carbonates (CO ). Phosphate and carbonate produce comparable results for oxygen isotope ratios, but less sample is needed for carbonate, preparation is less demanding, and results between laboratories are more comparable. 

The analysis proceeds through the sampling of tooth enamel to obtain the isotopic signal of the place of birth. The local isotopic signal can be determined in several ways in human bone from the individuals whose teeth are analyzed, from the bones of humans or archaeological fauna at the site, or from modem fauna in the vicinity. The local geological isotope signals of strontium have been constant over the last several 1,000 years. These isotope ratios have been reported for the rocks. 

The place of origin of prehistoric people can also be determined. The isotopic proveniencing of human remains, using ratios of strontium isotopes, has been employed in archaeology for approximately 20 years. Strontium isotope analyses have been used successfully in a number of studies. The basic principle involves comparison of isotope ratios in human tooth enamel with local levels in bone or other materials. Because isotopic ratios vary geographically, values in human teeth (marking place of birth) that differ from the local ratio (place of death) indicate migration. This method of analysis is described in more detail in Chap. 8, Provenience and Provenance. 

Mass spectrometers usually measure two or more isotopes at one time and calculate their ratio. Standards are measured at the same time in order to confirm the precision of the instrument and allow corrections to be made if needed. The results of the analysis provide the ratio measurements along with several other kinds of information. Table 4.2 shows some typical results from a mass spectrometer, in this case a Ust of calculated strontium isotope ratios on human tooth enamel measured on TIMS. The first column in the table gives the sequential lab number for each individual sample. The site is the place from where the sample comes. The corrected Sr/ Sr is the isotope ratio for strontium in the sample, corrected on the... 

In-situ elemental and Sr isotope investigation of human tooth enamel Nd YAG213nm ICP-Q-MS and MC-ICPMS Trace element (obtained using LA-ICP-Q-MS) and Sr isotopic (obtained by means of LA-MC-ICPMS) analysis of human tooth enamel to decipher historical population migrations Simonetti et al. [109]... 

Empirical and experimental data have indicated that different bone tissues reflect different components of the diet (27-22). In general, bone collagen is produced primarily from the protein portion of the diet, while bone apatite and tooth enamel are produced from a mixture of dietary protein, carbohydrates and fats. Stable isotope analysis of both bone collagen and apatite thus permits quantitative estimates of several dietary components. Both bone collagen and apatite are constantly being resorbed and replenished, so that their isotopic composition reflects dietary averages over at least the last several years of an individual s life. The apatite in tooth enamel, however, is not turned over, and represents diet at the time of tooth formation, often from a pre-weaning age. 

Montgomery, (. (2010) Passports from the past investigating human dispersals using strontium isotope analysis of tooth enamel. Ann. Human Biol, 37 (3), 325-346. 

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