Comparison of Different Swabs for Sampling Inorganic Gunshot Residue from Gunshot Wounds: Applicability and Reliability for the Determination of Firing Distance

Abstract

This study concentrates on samples of bare pork skin, with and without bristles, and dried bovine ribs shot with a semi-automatic pistol to find the best methodology and sampling surface in the search for inorganic gunshot residues (IGSR). Four quadrants of known surface areas were sampled at different distances from the bullet's hole with different swabs: tapes in graphite, Leukosilk® white tape, 3M® transparent tape, and a cotton swab to assess the technique able to collect the highest amounts of IGSR with the lowest contribution of the blank. The cotton swab wet in 10% HNO gave the best results. The highest amounts of IGSR, measured by ICP-OES and MS, were detected on a surface of 3-cm radius from the bullet's edge. The amount of metals collected decreased with the firing distance between 20 and 60 cm. The procedure was efficient for sampling different tissues like skin and bones.

A distant relationship?—investigation of correlations between DNA isolated from backspatter traces recovered from firearms, wound profile characteristics, and shooting distance

“…in combination with a gunshot residue (GSR) analysis still appears to be the most productive approach for reliable differentiation between certain distances [11]. Particularly, the detection, quantification, and correlation of GSR with the shooting distance has been (with a focus on staining, e.g., [27]) and still is a promising field of research, including GSR detection via micro-CT [28] and the analysis of inorganic GSR [29] by emission spectrometry and mass spectroscopy, which, however, require advanced lab equipment. Hlavaty et al performed a microscopic, histological analysis of the tissue surrounding the bullet entry site to estimate the shooting distance but also concluded that this approach is not suitable for forensic routine analysis [30].…”

Reviewing Research Trends—A Scientometric Approach Using Gunshot Residue (GSR) Literature as an Example

“…For example, in the author network analysis, Amadasi was found to be the most prolific in co-authorship, and their last paper on gunshot residue was published in 2016. Using the search engine ResearchGate, another paper on gunshot residue was published in 2018 by Amadasi et al [34]. This discrepancy arose because ResearchGate reported the initial publication date as July 2018 and the Journal of Forensic Science where the article was published did so in 2019, and as such, the paper was not included within the Scopus search results.…”

Interpol Review of Gunshot Residue 2019 to 2021

“…In [ 104 ], an investigation was conducted to compare different swabbing techniques and sampling areas, this to determine for shooting distance estimation the best sampling device and optimal sampling area around a gunshot wound. Inductively coupled plasma optical emission spectrometry and inductively coupled plasma mass spectrometry were used as quantification techniques.…”