Comparative Forensic Profiling of Primer-Derived Inorganic Gunshot Residues Using SEM-EDX Spectroscopy

Abstract

Gunshot Residue (GSR) analysis presents a significant challenge in forensic science due to the need to detect and identify minute traces of powders and initiating compositions formed during the chemical decomposition and deflagration processes within cartridge cases. This research is a qualitative comparative profiling study, designed to create a reference database of the most characteristic elemental markers for commonly used ammunition types in Europe and the Middle East. This study focuses on characterizing inorganic GSR using Scanning Electron Microscopy coupled with energy-dispersive X-ray Spectroscopy (SEM/EDX). Inorganic residue samples were collected from cartridge cases of American, German, Italian, Belgian, and Egyptian ammunition following firearm discharge. A comparative investigation was conducted to identify and differentiate the elemental compositions of primer residues associated with each ammunition type. The results revealed distinct elemental signatures, with metals such as lead (Pb), Barium (Ba), antimony (Sb), and Calcium (Ca) serving as key indicators for residue identification. SEM/EDX analysis provided high-resolution morphological and elemental data, allowing for the differentiation of GSR particles based on their origin. The findings support the use of SEM/EDX as a reliable tool for comparative GSR analysis, contributing to the forensic differentiation of ammunition types based on their inorganic residue profiles.