NCJ Number
76890
Journal
Journal of Forensic Sciences Volume: 26 Issue: 2 Dated: (April 1981) Pages: 263-287
Date Published
1981
Length
25 pages
Annotation
A photoluminescence technique, which detects lead and antimony in gunshot residue, was evaluated for use in investigations of apparent gunshot suicides.
Abstract
The study was conducted in conjunction with forensic science laboratories in five U.S. cities (Los Angeles, Calif; Phoenix Ariz; Dallas, Tex; Atlanta, Ga; and Baltimore, Md.). Samples were collected by the adhesive lift method from the backs of the hands of 67 gunshot suicide victims, 41 subjects who died of other causes, and 31 live subjects with high occupational exposure to lead and antimony. The photoluminescence instrumentation included spectrofluorometers equipped with xenon lamp excitation sources and with both scanning excitation and emission monochromators. The photoluminescence technique for the quantitative detection of lead and antimony is based on the strong luminescence observed at low temperatures for halogenion complexes of certain metals. As a result, tentative simultaneous threshold levels of 0.85 microgram for lead and 0.01 microgram for antimony were selected as criteria for presuming the presence of gunshot residue on samples from the hands of suicide victims. Although blood decreases the detectability of lead and antimony in the samples, 48 percent of the suicide cases involving handguns other than .22 revolvers exceeded the threshold levels for both lead and antimony. Methods are suggested for eliminating the effects of blood, and these should significantly increase the success rate for cases involving handguns. A much lower success rate was obtained for cases involving .22 revolvers and long guns because of the sparse amounts of residue produced by these guns. Data tables and an 11-item reference list are included. (Author abstract modified)