NCJ Number
78687
Journal
Forensic Science International Volume: 18 Issue: 1 Dated: (July/August 1981) Pages: 85-92
Date Published
1981
Length
8 pages
Annotation
This paper describes a method for the quantitative determination of nitrites present in gunshot residues, using an ultraviolet-visible spectrophotometer routinely employed in colorimetric procedures.
Abstract
The method involves the quantitative formation of a chromophoric complex between the nitrites present in the extract gunshot residue and the analytical reagents. The test samples were prepared by firing a .38-caliber revolver at a 90-degree angle into a piece of white cotton cloth. A portion was removed from the target material and the nitrites extracted. The sample material was tested for complete removal of nitrites with the modified Gneiss technique. The data were collected and a curve prepared relating the concentration of the nitrites present in the samples to the muzzle-to-target distance. In addition, 10 blind samples were prepared with the same revolver and using the same procedures as under the test sample. The results demonstrate the feasibility of using this method for the quantitation of nitrites present in gunshot residues. Data tables, graphs, and 17 references are included. (Author abstract modified)