by Kenneth Ujevich
In order to learn more about the persistence of gunshot residue (GSR) in soft tissue and bones during decomposition in marine environments, a quantity of 36 fleshed and 36 defleshed bovine ribs were shot at contact range with 0.22 caliber hollow point ammunition using a Stirling 0.22 caliber long rifle. Bone specimens in triplicate were placed in three environments: submerged, intertidal and in the supralittoral zone, which is never submerged by water but is influenced by sea spray and splashing. Sets of triplicates were recovered on days 3, 10, 24 and 38, and analyzed with scanning electron microscopy with energy dispersive X-ray spectrometry (SEM–EDX), and inductive coupled plasma mass spectrometry (ICP-MS). The SEM–EDX recorded GSR-indicative particles surrounding the bullet entrance on the fleshed and defleshed bones in all environments throughout the study. GSR-unique particles were only detected on the supralittoral bones. The ICP-MS analysis showed the fastest GSR loss on submerged defleshed specimens. Fleshed specimens showed a faster GSR loss on intertidal than submerged and supralittoral specimens. In general, the GSR disappeared faster from submerged and intertidal than non-submerged specimens. The difference of detection of GSR between analyzed specimens (defleshed versus fleshed) disappeared upon defleshing. This study highlights the potential of finding evidence of GSR in a submerged body and the potential of microscopic and analytical methods for examining suspected gunshot wounds in highly decomposed bodies in marine habitats.
Anne-Christine Lindström, Jurian Hoogewerff, Josie Athens, Zuzana Obertova, Warwick Duncan, Neil Waddell, Jules Kieser. “Gunshot residue preservation in seawater.” Forensic Science International, Volume 253, August 2015, Pages 103-111, ISSN 0379-0738, http://dx.doi.org/10.1016/j.forsciint.2015.05.021.