Investigating gunshot wounds in charred bone with XRF spectroscopy: a technical note

Area of Science:

• Forensic Science
• Materials Science
• Analytical Chemistry

Background:

• Analyzing injuries on charred human remains is challenging due to high alteration and fragmentation.
• Traditional methods for detecting gunshot residues (GSR) may be difficult on extensively damaged or cremated samples.

Purpose of the Study:

• To evaluate X-Ray Fluorescence (XRF) as a rapid screening tool for identifying GSR on cremated and fragmented bone.
• To determine if GSR can survive the cremation process and be detected on skeletal remains.

Main Methods:

• Bovine ribs (skeletonized and with soft tissue) were subjected to 9mm projectile impacts.
• Samples were cremated to complete calcination in an electric furnace.
• Entry wounds were analyzed using X-Ray Fluorescence (XRF) for elemental composition.

Main Results:

• XRF successfully detected traces of lead (Pb) and/or antimony (Sb) in GSR near the impact lesions on most samples.
• Samples impacted by unjacketed bullets showed a more significant and widespread presence of lead.
• GSR elements persisted on the bone matrix even after cremation.

Conclusions:

• X-Ray Fluorescence (XRF) is a viable, non-destructive technique for the rapid screening of gunshot residues on charred and fragmented bone.
• This method offers a conservative approach for preliminary analysis in forensic investigations involving cremated remains.
• XRF can aid in identifying ballistic events even when traditional evidence is compromised by thermal damage.