ANALYSIS OF GUNSHOT RESIDUES BY LA-ICP-MS

The aim of this work was detection and elementary analysis of gunshot residues from hands of shooter by means of LA-ICP-MS method. Gunshot residues belong to the group of microtrace. Gunshot residues are solid metal and non-metal particles. These particles are submicroscopic size. These calibres were investigated: 22 LR SB 7,65 Br. SB 9 mm Luger SB 45 AUTO S&B. Gunshot residues were determined on the basis of combination of characteristic elements (Pb, Ba, Sb or Sn). Correlation matrix and Spearman correlation were used for statistical evaluation. Statistical evaluation was executed with program R. Significant non-homogeneousness of analyzed particles were observed. The composition of particles originating from the same cartridge is very variable what is caused by high temperature and pressure at shot. Hence the sorting of GSR to their originate cartridge is not possible.