NCJ Number
162851
Journal
Journal of Forensic Sciences Volume: 41 Issue: 1 Dated: (January 1996) Pages: 23-26
Date Published
1996
Length
4 pages
Annotation
This article describes a new method of chemically enhancing shoeprints.
Abstract
This study examines the use of pH indicators, Bromophenol Blue and Bromocresol Green, as chemical reagents for the enhancement of footwear marks. The performance of these reagents on various surfaces, such as plastic sheets, brown paper, cardboard, porcelain bathroom tiles and cotton cloth, was compared to that of the thiocyanate reagent described in the literature as the most effective. The pH reagents proved to be much more effective for dust shoeprint samples collected in various regions of Israel; the authors did not observe any significant enhancement of similar footwear imprints with ammonium thiocyanate. In order to elucidate the mechanism of the enhancement using the pH reagents, experiments were carried out to examine the pH changes occurring during their interaction with footwear marks residues. If enhancement of a shoeprint was not satisfactory after spraying with Bromophenol Blue solution, exposure of the print to a carefully controlled amount of water vapor significantly improved the enhancement. Figures, references