Analysis isotopic

The Scottish chemist Frederick Soddy first used the term isotope to describe his observation than atoms with different atomic masses have the same chemical properties and occupy the same position in the periodic table. Today we understand that the number of protons in the atomic nucleus defines the chemical properties and the identity of an element, but there can be different numbers of neutrons associated with the same number of protons, resulting in the same element having several possible masses, or isotopes. 

Isotopes are involved today in virtually all areas of chemistry. The use of isotopes in archaeological chemistry is widespread and rapidly growing, with many different applications. Different isotopes are used with many different kinds of materials to answer a variety of questions. Some of these isotope ratios are listed in Table 4.1 along with additional information on their abundance in nature, the kinds of materials sampled, and the kinds of information obtained in archaeological applications. Isotopes of oxygen, carbon, nitrogen, and strontium isotopes are more commonly used in archaeological applications and are discussed in more detail in this chapter. 

Element Isotope ratio Natural abundance (%) Material analyzed Applications 

Carbon C/ C r = 98.89, 0=1.11 Bone, soils Diet, environment, source 

Lead 2O8pb/2O6pb Pb=24.1, - Pb = 52.4 Bone, pottery, metals Origin, source  

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Shackleton, N. J. (1967). Oxygen isotope analyses and Pleistocene temperatures re-assessed. Nature 215, 15-17. 

Stable isotope analyses of the organic fraction of bone and of food samples was carried out on a Micromass Prism Mass Spectrometer in the Stable Isotope Laboratory, Department of Physics, University of Calgary, under the direction of H.R. Krouse. Collagen samples were combusted in a Carlo Erba gas analyser which provides information on the carbon and nitrogen content of the samples andintroduces Nior CO gases into the mass spectrometer for analysis of nitrogen or carbon stable isotopes, respectively. 

Bones of 19 individuals were analyzed for strontium, rubidium and zinc. The number of samples was limited by the availability of bone after the stable isotope analyses were completed. Strontium was analyzed in order to test for trophic level, and to compare to other results obtained in the region on prehistoric peoples (Katzenberg 1984). Rubidium is not expected in human bone, so its presence acts as a measure of contamination. The use of zinc as a paleodi-etary indicator has been questioned recently (Ezzo 1994) and we were interested to see if there was any relationship between zinc content in food and bone. 

Schwarcz, H.P. and Schoeninger, M.J. 1991 Stable isotope analyses in human nutritional ecology. Yearbook of Physical Anthropology 34 283-322. 

Sillen, A. 1988 Elemental and isotopic analyses of mammalian fauna from southern Africa and their implications for paleodietary research. American Journal of Physical Anthropology 76 49-60. 

Cerling, T., Harris, J.M., Ambrose, S.H., Leakey, M.G. and Solounias, N. 1998 Dietary and environmental reconstruction with stable isotope analyses of herbivore tooth enamel from the Miocene locality of Fort Tsmaa. Journal of Human Evolution 33 635-650. 

Sealy, J.C. 1996 Seasonality of rainfall around the Last Glacial Maximum as reconstructed from carbon isotope analyses of animal bones from Nelson Bay Cave. South African Journal of Science 92 441 144. 

Sharp, Z.D. and Cerling, T.E. 1995 A laser GC-IRMS method for in-situ carbon and oxygen isotope analyses of carbonates and phosphates. Geological Society of America, Abstracts Program 27 A255. 

These are only a few specific examples of paleodietaiy consequences of biochemical pathways. Paleodiet researchers shonld probably try to enlist the aid of metabolic biochemists in a search for other possible conseqnences of differential metabolic pathways, internal recycling of metabolites, etc. Furthermore, many of these problems will become clearer as we begin to have access to isotopic analyses of individnal amino acids or even specific carbon atoms at sites on individual AAs. 

Sperm-positive female Holtzman rats were started, one day after insemination, on the diets that their offspring would consume. Birth occurred 21 days after insemination and weaning occurred 21 days later sexes were separated prior to sexual maturity. Surplus individuals were sacrificed at weaning. Male and female pairs from each group were sacrificed at 91, 131 and 171 days after birth. Pairs on one diet were also sacrificed at 211 and 251 days after birth. Euthanasia was performed by exposure to COi. Isotopic analyses were... 

Carnivores rely on a protein-rich diet and produce new biomass primarily from dietary amino acids, although the enzymes required for de novo amino acid synthesis are present (Garmes et al., 1998). Bone collagen, muscle (meat) and apatite were analyzed for a set of modern southern African herbivores and carnivores (Lee-Thorp et al., 1989). The isotopic analyses showed i C enrichment in bone collagen, apatite and muscle, and depletion in lipids. Difference in values between herbivores and carnivores indicates a trophic effect, which for carbon in bone collagen is 2.5-3%o (Fig. 2). 

Calculation of an age requires the value of Na j N, which is used in Equation to calculate age, t. The ratio can be found from the isotopic analyses of a fresh carbon sample and the old sample. 

Aggarwal PK, ME Fuller, MM Gurgas, JF Manning, MA Dillon (1997) Use of stable oxygen and carbon isotope analyses for monitoring the pathways and rates of intrinsic and enhanced in situ biodegradation. 

Douglas, G. and Savin, S.M. (1973) Oxygen and carbon isotope analyses of Cretaceous and Tertiary foraminifera from the central North Pacific. Washington, D.C. U.S. Govt. Printing Office, Initial Reports of the Deep Sea Drilling Project, 17, 591-605. 

Shackleton, N.J. and Kennett, J.P. (1975a) Paleotemperature history of the Cenozoic and the initiation of Antarctic glaciation oxygen and carbon isotope analyses in DSDP Sites 277, 279, and 281. Initial Reports of the DSDP, 29, Washington, D.C. U.S. Gov. Printing Office, pp. 743-755. 

Of the radioassays that are commonly used to quantify americium, a-spectroscopy is used when isotopic analyses of americium must be conducted (e.g., 241Am and 243Am). 243Am is often added as a tracer to estimate the efficiency of the sample preparation method when quantifying 241Am in biological matrices. 

Gulson B, Wilson D. 1994. History of Lead Exposure in Children Revealed from Isotopic Analyses of Teeth. Arch Env Health 49(4) 279-283. 

The aims of this contribution are to (i) consider the theoretical principles underlying the use of compound-specific stable isotope analysis in archaeology (ii) consider the practical aspects of undertaking compound-specific stable isotope analyses and (iii) demonstrate the value of linking the structures of amino acids, fatty acids and/or sterols, to their compound-specific stable isotope values to achieve new insights into variations in metabolism and environment in order to enhance archaeological interpretations. 

Compound-specific stable isotope analyses are more complex to undertake than bulk stable isotope analyses and require careful consideration to be given to sample... 

The bulk hydrogen isotopic composition of amino acids has been shown to depend on animal trophic level (Birchall et al. 2005). Furthermore, compound-specific hydrogen isotopic analyses of amino acids may help elucidate the mechanism behind this enrichment, by determining the differences in 8D value between essential and non-essential amino acids, and may also provide a further palaeodietary indicator (e.g. Corr et al. 2005). However, amino acids are highly functional, with both amino and carboxyl extremely... 

Hayes, J. M., Freeman, K. H., Popp, B. N. and Hoham, C. (1990) Compound specific isotopic analyses a novel tool for the reconstruction of ancient biogeochemical processes. In Advances in Organic Geochemistry 1989 (Eds Durand, B. and Behar, F.), Pergamon Press, Oxford, pp. 1115 1128. 

Since the IM-20 had not previously been used for high precision isotopic measurements and since previous isotopic measurements with other ion microprobes [24,25] were characterized by percent level relative errors, we carried out an extensive series of Mg isotopic analyses of terrestrial samples. Terrestrial standards were especially emphasized prior to the study of meteoritic samples, but were also periodically interspersed with later meteoritic analyses as a check on the performance of the ion probe. Terrestrial standards included Ceylon spinel (MgAl204), Madagascar hibonite (CaA112019), a suite of olivines (Fo 100 to Fo 5) used in... 

Stable Isotope Analyses of Byrd Station Cores and Inter-hemispheric Climatic Implications, Science, 1970. 168,... 

Selected sphalerite grains (n=15) were mounted and analyzed by electron microprobe. Isotopic analyses of Pb were conducted on galena and sphalerite grains at Carleton University. Sulphur isotope analyses were performed on sphalerite powders at the University of Ottawa. 

The Institute of Isotopic and Molecular Technology, Cluj-Napoca, performed all the analyses. The routine isotopic analyses were run on a Thomson THN 202D mass spectrometer, with a working precision of 0.3%o. The uranium method was used to release hydrogen from water. All isotopic data are expressed in conventional 5 notation as the permil deviation of D/H ratios with respect to the V-SMOW standard. 

Results of 87Sr/86Sr and 143Nd/144Nd, and 34S isotope analyses (for both altered and fresh rock samples) range between... 

Cox, G., Sealy, J., Schrire, C. and Morris, A. (2001). Stable carbon and nitrogen isotopic analyses of the underclass at the colonial Cape of Good Hope in the eighteenth and nineteenth centuries. World Archaeology 33 73-97. 

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