Bone samples

Nineteen bone samples were prepared for analysis of the trace elements strontium (Sr), rubidium (Rb), and zinc (Zn). The outer surface of each bone was removed with an aluminum oxide sanding wheel attached to a Dremel tool and the bone was soaked overnight in a weak acetic acid solution (Krueger and Sullivan 1984, Price et al. 1992). After rinsing to neutrality, the bone was dried then crushed in a mill. Bone powder was dry ashed in a muffle furnace at 700°C for 18 hours. Bone ash was pressed into pellets for analysis by x-ray fluorescence spectrometry. Analyses were carried out in the Department of Geology, University of Calgary. 

Of the three elements for which analyses were carried out, only strontium is thought to have potential as a dietary indicator (reviewed by Sandford 1992 Ezzo 1994 Burton and Price, this volume). Mean Rb for 19 samples is 6 ppm with a standard deviation of 0.7 ppm. Mean Zn for 19 samples is 571 ppm with a standard deviation of 220 ppm. The range for zinc is very large with a minimum value of 267 and a maximum value of 1,144. This range suggests that there is little to be learned regarding diet or physiology. Trace element results for bone samples are presented in Table 1.4. 

The diet of the 19 century residents of Upper Canada was determined from historical sources and was reproduced in order to carry out chemical analysis. Stable carbon isotope analysis of food and human bone demonstrates that the spacing between the food eaten and the bone collagen is around 5.6%o. The value may vary slightly from this estimate since the latter is based on a reconstructed diet and a large number of bone samples, which exhibit a small amount of variation. Nevertheless, this empirically derived result agrees well with estimates from field (Vogel 1978), and laboratory studies (reviewed in Ambrose 1993). 

Figure 3.2. Average carbon isotopic ratios for all human, herbivore, carnivore, and omnivore bone samples from the European Holocene in the data base A Uncorrected ratios (Cu) B climate-corrected ratios (Cc). Only countries with more than 10 samples are included. For a description of the climatic correction procedure see text. 

Tabic 3.2. A comparison of the average 5 Cj and 5 Cc values of human, herbivore, carnivore, and omnivore bone samples from the European Holocene. 

In addition, our results suggest that removal of hpids improves both yield characteristics and elemental characteristics. Recent work by Liden et al. (1995) suggests that the methanol-chloroform method used here is more effective than other methods, such as treatment with NaOH solution, or the maintenance of an acidic environment and ultrafiltration of products during collagen extraction. It is speculated that the presence of hpids in archaeological bone samples may interfere with the acid hydrolysis of protein during... 

To enable comparison to this experimental approach, archaeological human bones of various ages and soil properties (Table 9.1) from the Anthropological Collection in Munich were analyzed. All German skeletal series come from humic soil with, neutral to slightly basic pH. The samples from Tinkey, Syria, coastal Pern and Egypt have been buried in dry, sandy soils. Soil samples from most of the excavation sites were available and bone sample... 

Figure 9.4. Non-proteinogenetic amino acids in NCP s from all archaeological human bones. The values are the averages of all archaeological human bone samples taken together (cf Table 9.1). Dark columns mineral-bound NCP light columns serum proteins. Most non-proteinogenic amino acids are extracted with the serum proteins.

Since it is possible to differentiate well-preserved from badly preserved collagen through amino acid analysis and gel electrophoresis, it is also possible to determine which bone samples are likely to give erroneous isotopic ratios. At least for 8 C, it should be possible to estimate the in vivo isotopic signature by correcting the changed amino acid concentrations of the collagen extract. This way, a reasonable approach to the reconstruction of pale-odiet should be possible. 

On the other hand, the scrambled model of carbon sourcing does not seem to be applicable when we consider the metabolic fate of fatty acids. We find that there are partial barriers to the movement of FA-derived carbon atoms into the synthesis of proteins. This partial restriction leads us to expect a trophic level effect in the fractionation between collagen and bone apatite or respired CO2 of which apatitic carbonate is a sample. The magnitude of the fractionation depends on two separate fractionation factors which cannot be disentangled by analyses of bone samples alone. 

The measurement of U-series isotopes using laser ablation will potentially reduce the damage inflicted on specimens to almost zero. The increased spatial resolution will allow profiles, as required by the D-A model, to be measured quickly and simply in the smallest of bone samples and across thin layers of enamel (e g.. Fig. 11). Early studies (e.g., Belshaw et al. 2002 Eggins et al. 2002) have demonstrated the potential of the technique to provide U-series profiles for bones and teeth, but consistent and fully quantitative results are still a little way off. 

Musculoskeletal Effects. Information regarding musculoskeletal effects in humans is limited to the findings of bone marrow peritrabecular fibrosis and decreased cellularity in bone samples taken from the corpse of a 64-year-old man who had been exposed to 241 Am (11 years earlier) when an ion-exchange column containing about 100 g of241 Am exploded in his face (Priest et al. 1995). The explosion resulted in... 

Bone Sample wet ashed, purified by solvent extraction a -Liquid scintillation 0.7 pCi/g 99% at 3,000 dpm spike Guilmette and Bay 1981... 

Bone Sample wet ashed, spiked with 243Am, and purified by anion exchange resin column, solvent extraction, and electrodeposition a -Spectrometry No data 98% Mclnroy et al. 1985... 

Chettle DR, Scott MC, Somervaille LJ. 1991. Lead in bone Sampling and quantitation using K X-rays excited by 109Cd. Environ Health Pespect 91 45-55. 

Mechanical Properties. The stress-strain and the hysteresis behavior of the polymers were measured on a Model 1122 Instron using dog-bone samples of 0.28 cm width and 1.0 cm effective length. The strain was measured using the displacement of the crosshead. In the calculation of the strain it was assumed that... 

The case of Oetzi (or the Iceman), the frozen mummy found in 1991 on the Alps on the border between Austria and Italy and now kept at the Archaeological Museum of Bolzano (Italy), is also well known. AMS radiocarbon measurements from the laboratories of Zurich[78] and Oxford[79] on tissue and bone samples from the Iceman dated him to 4550 19 years BP. When calibrated, this radiocarbon age corresponds to three probable calendar time intervals between 3350 BC and 3100 BC. Consistent measurements were obtained by dating some of his equipment and also botanic remains from the discovery site. [80] In this context, it is important to note that dating of Oetzi represents a good example of the relevance of the behaviour of the calibration curve in the final precision of a radiocarbon measurement. Actually, in this case, despite a very high precision of the radiocarbon age ( 19 years), the special trend in the calibration curve around the dated period, i.e. in particular the so-called wiggles, prevents a more exact and unambiguous absolute age determination. 

Amino acid composition data and stable isotope ratios are being evaluated as sources of information to indicate the presence of non-indigenous organics in bone samples intended for radiocarbon analyses. The study is being conducted in the context of the planned 14C measurement of Pleistocene bone samples by high energy mass spectrometric methods. 

Figure 2. Organic residue following demineralization of human bone sample from (a) late Roman/Christian cemetery near Poundbury, Dorchester, England (sample supplied by Theya Molleson, British Museum) and (b) Upper Paleolithic site in...

Taylor, R. E., Slota, P., Fraction Studies on Marine Shell and Bone Samples for Radiocarbon Analyses, In Radiocarbon Dating, pp. 422-432, Berkeley University of California Press, 1979. 

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