Abstract

Background: Post-blast forensic analysis is a cornerstone of modern investigative science, assisting in reconstructing events, attributing responsibility, and presenting admissible evidence in court. Traditional colour spot tests, although rapid and cost-effective, suffer from low specificity and susceptibility to environmental factors, which limit their evidential value. Main body: This review explores the analytical advances in the detection of postblast residues, focusing on colour tests, thin-layer chromatography (TLC), ion chromatography (IC), identification of thermally decomposed PETN in GC-MS, and instrumental methods such as gas chromatography–mass spectrometry (GCMS) and high-performance liquid chromatography (HPLC). Colour tests remain valuable for on-site presumptive screening but are prone to false positives. TLC provides confirmatory separation of nitroaromatics, peroxides, and oxidizers, while IC enables quantitative nitrate and anion analysis with high specificity, even in environmentally stressed samples. Thermal decomposition yields unique degradation signatures, particularly for PETN, rengthening the evidential value in improvised explosive device (IED) investigations. Extended column chromatography enhances TNT resolution in complex soil matrixes. Advanced spectrometric methods (GC–MS, LC–MS/MS) provide ultra-trace detection and forensic admissibility but require expertise and infrastructure. Environmental factors such as rainfall, soil composition, and pH significantly affect residue persistence, underscoring the importance of rapid, integrated forensic workflows. Comparative tables, schematic diagrams, and charts highlight the methodological strengths, weaknesses, and practical applications.

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