Gunshot Residues on Dry Bone After Decomposition—A Pilot Study

Abstract

Very little literature exists concerning radiochemical and microscopic analyses of gunshot wounds in decomposed material, and even less concerning skeletonized samples; the most advanced technologies may provide useful indications for the diagnosis of suspect lesions, especially if gunshot wounds are no longer recognizable. However, we know very little of the survival of gunshot residues (GSR) in skeletonized samples. This study examined nine gunshot wounds produced on pig heads which then underwent skeletonization for 4 years, and four gunshot entries on human heads from judicial cases which were then macerated to the bone in water; the samples underwent scanning electron microscopy coupled with energy dispersive X-ray (SEM-EDX) analysis. Positive results for GSR were observed only in four of the nine animal samples and in all four human samples. Among the human samples, two lesions showed Pb and Sb, one lesion only Pb, and one Pb, Sb, and Ba. This pilot study showed the survival of GSR in skeletal material and therefore the crucial importance of SEM-EDX analyses on skeletonized material. Further studies are needed in order to ascertain the role of environmental modifications of GSR.

Gunshot residue preservation in seawater

“…As an attempt to identify bullet wipe on bone, Berryman et al [13] showed evidence of GSR on defleshed bone samples, deep within the bony wound tract after removal of the periosteum. Recently, Taborelli et al [10] presented evidence of GSR on bone lesions from the mandible and forehead of fully skeletonized animal models up to four years of decomposition in terrestrial environments (buried in pots and in open air). All samples were kept indoors to avoid eventual modification by weather conditions.…”

“…Studies on GSR in decomposed remains have been conducted on soft tissue [17,18], as well as on skeletonized remains [4,10,11]. A study by La Goo et al [18], used microwave digestion prior to ICP-MS to detect GSR of Pb, Ba and Sb in pigs shot multiple times.…”

“…There may be a link between the postmortem interval and the retention of GSR [10], but testing this relationship is challenging because of postmortem factors such as decomposition, burial conditions and scavengers. When analysing GSR, time requirements, high cost per sample or limitations of the sophisticated techniques used may also be an issue.…”

“…A c c e p t e d M a n u s c r i p t 3 Studies on GSR or bullet residue in skeletonized remains [4,10,11,19] have found evidence of GSR up to 90 years decomposition. Fischbeck et al [11] showed the presence of Pb in a finger bone of a murder victim by using PIXE analysis when soft tissue was absent.…”

Trace metal analysis by laser ablation-inductively coupled plasmamass spectrometry and x-ray K-edge densitometry of forensic samples

“…Only a few radiochemical and microscopic studies have been conducted regarding the analysis of gunshot wounds in decomposing remains (63,65,66,67).…”