Thermal persistence and physicochemical modification of inorganic gunshot residue (IGSR)
- 1Unit of Forensic Medicine and Forensic Sciences, Department of Public Health, Experimental and Forensic Medicine University of Pavia Pavia Italy
- 2Department of Drug Sciences University of Pavia Pavia Italy
- 3Department of Chemistry University of Pavia Pavia Italy
Abstract
In the medicolegal context, GSR analysis plays a key role in clarifying the dynamics of firearm‐related deaths, including lesion identification and firing distance determination. However, postmortem alterations of the body, such as thermal exposure, may influence the analysis of lesions and complicate interpretation. This study aimed to evaluate the persistence and modifications of GSR under different firing distances and thermal treatments using Scanning Electron Microscopy equipped with Energy‐Dispersive X‐ray Spectroscopy (SEM‐EDS) and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP‐OES). Ballistic tests were conducted on calcium–magnesium silicate substrates using a self‐reloading 9 × 21 mm pistol at five barrel‐to‐target distances (5–100 cm). To simulate fire exposure, a subset of the targets was heat‐treated in a muffle furnace for 30 min at 250, 750, and 1000°C. SEM‐EDS and ICP‐OES analyses were then performed, focusing on morphology and chemical composition. GSR remained detectable under all experimental conditions. Both firing distance and thermal exposure affected gunshot residues, leading to changes in morphology, particle size, and elemental composition. An antagonistic interaction between these variables on GSR composition was identified, indicating that, depending on the temperature exposure, metal concentrations may vary with firing distance. Among the metallic elements, lead showed the strongest response, as explained by its low melting point. Notably, at 1000°C, no particles fulfilled the ASTM E1588‐25 criterion for characteristic GSR (Pb, Ba, and Sb), rendering the trimetallic population undetectable. These results highlight changes in GSR characteristics compared to standard criteria, suggesting the need to adapt GSR protocols in cases of burned remains.
Related
- Ectopic heartworms as evidence in the forensic postmortem examination of a dog with a fatal gunshot wound
- One bullet, five compartments: a transregional gunshot trajectory and the limits of operative intervention
- Clinical burden and predictors of hospitalization in extremity gunshot wounds: A single-center retrospective study.
- Gunshot and explosion injuries of the eyes
- Selenium Alters the Tissue Distribution of Inorganic but Not Methylmercury in Zebrafish Larvae
BibTeX
@article{argentiero2026thermal,
title = {{Thermal persistence and physicochemical modification of inorganic gunshot residue (IGSR)}},
author = {Gianmarco Argentiero and Barbara Bertoglio and Nicolas Martinelli and Giulia Pezzoni and Giorgio Marrubini and Federica Maraschi and Giovanni Cecchetto and Silvia D. Visonà and Daniele Merli},
journal = {Journal of Forensic Sciences},
year = {2026},
month = aug,
doi = {10.1111/1556-4029.70434},
url = {https://doi.org/10.1111/1556-4029.70434},
note = {CC BY 4.0},
}
RIS
TY - JOUR
TI - Thermal persistence and physicochemical modification of inorganic gunshot residue (IGSR)
AU - Gianmarco Argentiero
AU - Barbara Bertoglio
AU - Nicolas Martinelli
AU - Giulia Pezzoni
AU - Giorgio Marrubini
AU - Federica Maraschi
AU - Giovanni Cecchetto
AU - Silvia D. Visonà
AU - Daniele Merli
PY - 2026
DA - 2026/08/10
JO - Journal of Forensic Sciences
DO - 10.1111/1556-4029.70434
UR - https://doi.org/10.1111/1556-4029.70434
AB - In the medicolegal context, GSR analysis plays a key role in clarifying the dynamics of firearm‐related deaths, including lesion identification and firing distance determination. However, postmortem alterations of the body, such as thermal exposure, may influence the analysis of lesions and complicate interpretation. This study aimed to evaluate the persistence and modifications of GSR under different firing distances and thermal treatments using Scanning Electron Microscopy equipped with Energy‐Dispersive X‐ray Spectroscopy (SEM‐EDS) and Inductively Coupled Plasma Optical Emission Spectroscopy (ICP‐OES). Ballistic tests were conducted on calcium–magnesium silicate substrates using a self‐reloading 9 × 21 mm pistol at five barrel‐to‐target distances (5–100 cm). To simulate fire exposure, a subset of the targets was heat‐treated in a muffle furnace for 30 min at 250, 750, and 1000°C. SEM‐EDS and ICP‐OES analyses were then performed, focusing on morphology and chemical composition. GSR remained detectable under all experimental conditions. Both firing distance and thermal exposure affected gunshot residues, leading to changes in morphology, particle size, and elemental composition. An antagonistic interaction between these variables on GSR composition was identified, indicating that, depending on the temperature exposure, metal concentrations may vary with firing distance. Among the metallic elements, lead showed the strongest response, as explained by its low melting point. Notably, at 1000°C, no particles fulfilled the ASTM E1588‐25 criterion for characteristic GSR (Pb, Ba, and Sb), rendering the trimetallic population undetectable. These results highlight changes in GSR characteristics compared to standard criteria, suggesting the need to adapt GSR protocols in cases of burned remains.
SN - 0022-1198
SN - 1556-4029
ER -