Teeth, analysis

Thermal neutron activation analysis has been used for archeological samples, such as amber, coins, ceramics, and glass biological samples and forensic samples (see Forensic chemistry) as weU as human tissues, including bile, blood, bone, teeth, and urine laboratory animals geological samples, such as meteorites and ores and a variety of industrial products (166). 

G. Dentine, K. Edwards, M. Jackson, D. Kantor, M. Kelley, K. Murphy, D. Valley, M. Valley, and M. Wilhite for donating or helping obtain teeth for analysis. 

During production and characterization of various internal animal tissue reference materials for a number of metals, a comparative study was performed for Pb in six bovine teeth and two bovine bone materials using calibration with a solid RM and two versions of wet chemical analysis with GF-AAS and electrochemical (DPASV) detection. There was good agreement in the range of approx. 1.3-3 tng/kg dry weight for all techniques used (Liicker et al. 1992). 

Eggins S, Griin R, Pike AWG, Shelly M, Taylor L (in press) Th profiling and U-series isotope analysis of fossil teeth by laser ablation-lCPMS. Quat Sci Rev Falgueres C, Bahain J-J, Yokoyama Y, Arsuaga JL, Bermudez de Castro JM, Caibonell E, Bischofif JL, Dolo J-M (1999) Earliest Humans in Europe the age of TD6 GranDolina, Atapuerca, Spaim J Human Evol 37 343-352... 

The supposed human remains were accompanied by flint implements and animal teeth, all of which apparently supported the early date attributed to the find. The flint implements were of a reddish color, matching that of local flints, but spectrographic analysis revealed that they had been artificially stained with chromium and iron salts below the layer of stain there was a white crust, whereas local flints were brown throughout. The animal teeth also seemed to have been "planted" at the burial site so as to suggest an early date the red-brown color of the teeth had also been artificially stained chromium and iron had been found when they were analyzed. A hippopotamus tooth, previously supposed to be contemporary with the tool carved from the elephant s tusk, was also stained with chromium and iron salts and contained little fluorine. 

The isotopic distribution of lead (IDMS) in shed teeth from children has been shown to be useful in studies of the history of exposure to lead, including the definition of the source of the exposure, e.g., mine dust vs. food (Gulson and Wilson 1994), so IDMS certainly has important applicability, if not for routine determinations. ICP/MS, however, is easier, more sensitive, allows for multi-element analysis, and provides isotopic data. 

Stott, A. W. and Evershed, R. P. (1996) 813C analysis of cholesterol preserved in archaeological bones and teeth. Analytical Chemistry 68, 4402 4408. 

Mansilla, J., Solis, C., Chavez-Lomeli, M.E., and Gama, J. E. (2003). Analysis of colored teeth from Precolumbian Tlatelolco postmortem transformation or intravitam processes American Journal of Physical Anthropology 120 73-82. 

Recently, Yekkala et al. [144,145] have proposed an HPLC method with fluorescence detection. The method involves a rather laborious sample preparation due to the peculiar nature of the substrate involved (teeth), including pulverization, demineralization, hydrolysis of dentin and derivati-zation with o-phthaldialdehyde and A-acetyl-L-cysteine in order to obtain the enantioseparation of aspartic acid. Using a similar procedure, Benesova et al. [146] found that, in comparison with GC, HPLC provides shorter analysis time and higher sensitivity. 

MacHugh, D. E., C. J. Edwards, J. R Bailey, D. R. Bancroft, and D. G. Bradley (2000), The extraction and analysis of ancient DNA from bone and teeth A survey of current methodologies. Ancient Biomol. 3, 81-103. 

One theory, based on the pollen analysis, suggests that when Otzi returned from a trip to higher altitudes, he got into a dispute with some people in the village. According to the isotope evidence coming from the Iceman s bones and teeth, he was familiar with the area, so he would have probably known the villagers—they may have even been relatives. Otzi retreated back into the moimtains after the fight, only to die at the hands of a skilled archer. 

Analyte is measured at parts per million ( xg/g) to parts per trillion (pg/g) levels. To analyze major constituents, the sample must be diluted to reduce concentrations to the parts per million level. As we saw in the analysis of teeth, trace constituents can be measured directly without preconcentration. The precision of atomic spectroscopy, typically 1-2%, is not as good as that of some wet chemical methods. The equipment is expensive, but widely available. Unknowns, standards, and blanks can be loaded into an autosampler, which is a turntable that automatically rotates each sample into position for analysis. The instrument runs for many hours without human intervention. 

The lower limit of quantitation is 0.5 ng/L (parts per trillion). To measure such small quantities requires extraordinary care at every stage of analysis to prevent contamination. Mercury amalgam fillings in a worker s teeth can contaminate samples exposed to exhaled breath. 

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