This work investigates the chemical nature of fingerprints to ascertain whether differences in chemical composition or the existence of chemical markers can be used to determine personal traits, such as age, gender, and personal habits. This type of information could be useful for reducing the pool of potential suspects in criminal investigations when latent fingerprints are unsuitable for comparison by traditional methods. Fin-gertip residue that has been deposited onto a bead was extracted with a solvent such as chloroform. Samples were analyzed by gas chromatogra-phy/ mass spectrometry (GC/MS). The chemical components identified include fatty acids, long chain fatty acid esters, cholesterol and squalene. The area ratios of ten selected components relative to squalene were calculated for a small preliminary experiment that showed a slight gender dif-ference for three of these components. However, when the experiment was repeated with a larger, statistically designed experiment no significant differences between genders were detected for any of the component ratios. The multivariate Hotelling's T2 test that tested all ten-component ratios simultaneously also showed no gender differences at the 5% significance level.

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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Web site http:llw.ntis.govlordering.htm Reports are available to U.S. Department of Energy (DOE) employees, DOE contractors, Energy Technology Data Exchange (El_DE) representatives, and International Nuclear Information System (INIS) representatives from the following source. Office of Scientific and Technical Information P.O. BOX 62 Oak Ridge, TN 37831

The stability of volatile organic compounds in environmental water samples has been studied, particularly with respect to the establishment of preanalytical holding times. Methods have been developed for the preparation of standard samples containing known concentrations of volatile organics. Three water samples were used: distilled water, surface water, and groundwater. Samples were stored at both room temperature and under refrigeration. Data were collected over a 365-day period by gas chromatography /mass spectrometry. In water samples containing low chloride content (distilled water), rapid dehydrohalogenation of tetrachloroethane to trichloroethylene occurred. Such degradation was also evident in the surface water and groundwater samples stored at room temperature. A less rapid conversion of trichloroethane to dichloroethylene occurred in distilled water samples stored at 25 °C. Reduced concentrations of aromatic volatiles were observed in both surface and groundwater matrices after 28 days. Loss of carbon tetrachloride was also apparent in surface water samples stored at room temperature. Subsequently, experiments were conducted to determine the value of reduced pH in sample preservation. It was shown that acidification with hydrochloric acid effectively prevented degradation and allowed indefinite storage. However, sampling and analytical considerations make the use of HC1 impractical. Therefore, a study was carried out using sodium bisulfate and ascorbic acid as preservatives. Both substances effectively preserved the samples, but sodium bisulfate proved to have several advantages over ascorbic acid. Samples preserved with either acid were stable over the 112-day experimental period.The implication is that with preservation the maximum holding times for such samples will be limited only by the need for sample turnaround.