Problems of Forensic Sciences 2000 Vol. 41 (XLI) 62-86
SEM-EDX STUDY OF INORGANIC GUNSHOT RESIDUES FROM MAKAROV 9 MM AMMUNITION
Zuzanna BROŻEK-MUCHA
Institute of Forensic Research, Cracow
Streszczenie
Selected aspects of examinations of inorganic gunshot residues arising from use of P-64 or P-83 pistols and Makarov 9 mm ammunition are presented in the work. The subjects of the study were: seven sets of samples collected from shooters' hands directly after performing various numbers of experimental shots, with the use of different self-adhesive materials; and three sets of evidence material concerning gunshot cases examined in the Institute of Forensic Research, Cracow. All the samples were analysed with the SEM-EDX method using an automated program of searching for defined features. The total number of particles found was different for each of the studied sample sets. However, for each set a similarity in proportions of numbers of particles of certain elemental contents was observed. It was found that, among the entire population of particles originating from the primer, the most numerous group was that of indicative antimony particles, whereas unique Pb-Sb-Ba particles occurred in very small numbers. These facts should be taken into account when formulating an expert report in cases of finding only indicative particles. It has been proposed that in such cases conclusions should be drawn with the use of a probability scale. Repeatability of the results obtained for the experimental samples as well as their similarity to the selected evidence samples was checked by means of non-parametric statistical methods: R-Spearman and t-Kendall rank correlation coefficients.
Słowa kluczowe
Gunshot residues (GSR)/Cartridge discharge residues (CDR); SEM-EDX; Non-parametric statistical methods; R-Spearman rank correlation coefficient; t-Kendall rank correlation coefficient.