Ti) to use for discrimination among the glass samples. This multi-element discrimination showed a significant improvement in the discrimination statistics over using only refractive index (RI) measurements. Oak Ridge National Laboratory (ORNL) recently analyzed fragments from 76 of the original side window fragments using inductively coupled plasma mass spectrometry (ICP-MS). The ICP-MS analyses measured 45 elements using a hierarchical sampling scheme to estimate variances due to sampled population (V P ), variance due to sample dissolution and within sample heterogeneity (V D ), and variance due to replicate measurements (V M ). The between-to-within ratio [B/W ~VP /(V D 1 V M )] afforded a measure of the variance within the population to that in the analytical measurement, providing a first approximation of the discriminating power of each element. Florida International University updated the RI measurements on 72 available glass fragments. These RI measurements along with ICP-AES and ICP-MS elemental analyses were used for pairwise comparisons of all possible pairs of the 72 glasses that had a complete set of measurements. The pairwise comparisons used Tukey's HSD method to compare RI and element-by-element discrimination potential of ICP-AES and ICP-MS for analyzing glass in forensic casework.

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The influence of oxygen content, conducting host matrix, and soil composition on the quantitative determination of trace elements in soils by glow discharge mass spectrometry was examined. Oxygen content and conducting host matrix identity influenced relative sensitivity factors employed in the quantitative interpretation of the glow discharge mass spectra. Soil composition did not influence these relative sensitivity factors. Unknown soils taken from the field were analyzed with the use of a set of relative sensitivity factors obtained from standard soils with certified compositions. The quantitative results from glow discharge mass spectrometry of these unknowns compared favorably with quantitative results from inductively coupled plasma atomic emission spectrometry and laser ablation solid sampling inductively coupled plasma mass spectrometry.