An automated image analysis (IA) technique has been developed to obtain a m
easure of the amount (i.e. number and area) of gunshot residue (GSR) partic
les within and around a gunshot wound. Sample preparation and IA procedures
were standardised to improve the reproducibility of the IA measurements of
GSR. Measurements of GSR from test firings into goat hide were enhanced by
staining the barium and lead components present on the skin sections with
Alizarin Red S. The amount of GSR detected on the stained skin sections was
compared with backscatter electron micrographs of the same sections. The d
ifferences were deemed to be insignificant when the variability in the repe
ated test firings were taken into consideration. Preliminary results indica
ted that the decreasing relationship between firing range and the amount of
GSR deposited was non-linear, and that for firing ranges of up to 20 cm th
e amount of GSR deposited from repeated shots fired from the same distance
was highly variable. (C) 1999 Elsevier Science Ireland Ltd. All rights rese
rved.