Evaluation of persistence of gunshot residue (GSR) using graphite furnace atomic absorption spectrometry (GFAAS) method

In this study, the contents of Sb, Pb, and Ba in GSR collected simultaneously from the hands and clothes of the shooter and the barrel of the firearm, were determined by GFAAS in order to determine the time-dependent persistence of GSR. The most intensive GSR was found in the samples collected from the hands of the shooter, and it was observed that the persistence of GSR is longer on the barrel of firearms since this area is less prone to the effects of environmental conditions. Therefore, we were able to analyze the gunshot residues deposited on the barrel of the firearm in a longer time interval. The average half-time of the GSR particles obtained from the hands and clothes of the shooter was found to be one hour. The importance of the time factor in collecting the samples is evident from the findings. The density of the GSR detected varies depending on the type of ammunition used. Although the density of the GSR collected from the hands and clothes of the shooter depends on the type of firearm, it is evident that the surface and environmental factors are very important for the persistence of residues collected.