Trace Analysis of Nitrate Content in Soil Samples using Ion Chromatography from Forensic Perspective

Soil samples are often sent to Forensic Science Laboratories (FSLs) as exhibits to determine the presence of explosive residues in post-blast cases. This work focuses on the trace analysis of nitrate ion (NO3¯) content in the soil samples using Ion Chromatography (IC), an essential technique for inorganic explosives ion detection and confirmation. Soil was collected from the Talegaon area in Pune for spiking the standard case sample and to use as control soil to compare and find out the homogeneity of explosive content in the soil matrix. Soil samples of varying quantities - 50g, 40g, 30g, 20g and 10g were collected to assess the minimum sample mass required for reliable nitrate ions detection. A sensitive ion chromatographic method was used to detect the presence of nitrate ions. The findings provide crucial insights into the sampling and threshold soil mass necessary for the analysis of nitrate ions in trace amounts. Our study aligns with the development of standardized forensic protocols for explosive residue identification in post blast soil samples. Key Words: forensic, trace analysis, explosive, soil, ion chromatography, nitrate ion