Determining the lifetime of detectable amounts of gunshot residue on the hands of a shooter using laser-induced breakdown spectroscopy.
Laser-induced breakdown spectroscopy (LIBS) has been used to determine the period of time that a shooter will test positive for gunshot residue (GSR) after firing a revolver. Multiple rounds of primer were fired and samples collected at multiple hour intervals using an adhesive tape pressed against the skin. Samples were analyzed directly using a commercially available laser-induced breakdown spectrometer where barium emission (originating from barium nitrate in the primer) was observed. Population statistics were used to compare suspected GSR to a library of blank samples from which a threshold value was established. Statistically significant results, positive for GSR, are obtained 5.27 days after a firearm discharge using these techniques.
Rosenberg
Matthew B
MB
Department of Chemistry and Biochemistry, Kennesaw State University, Kennesaw, Georgia 30144, USA.
Dockery
Christopher R
CR
D001464:Barium / Q000302:isolation & purification; D005389:Firearms; D044709:Forensic Ballistics / Q000379:methods*; D005554:Forensic Medicine / Q000379:methods*; D006230:Hand Injuries / Q000473:pathology*; D006801:Humans; D012867:Skin / Q000737:chemistry; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000295:instrumentation / Q000379:methods*; D013997:Time Factors
D001464:Barium