NCJ Number
187620
Journal
Journal of Forensic Sciences Volume: 46 Issue: 2 Dated: March 2001 Pages: 352-355
Date Published
March 2001
Length
4 pages
Annotation
The increasing incidence of assault that involves lachrymator sprays has produced an increase in items being submitted to the authors' laboratory for the analysis of the associated chemical residues; this paper reports on a study undertaken to identify an efficient solvent with which to extract the compounds of interest from cotton fabric.
Abstract
This paper details the procedures used to identify a preferred solvent. Ethyl acetate was established as the most effective solvent for achieving maximum recovery of 2-chlorobenzylidenemalononitrile from "CS Gas" and capsaicin, as well as dihydrocapsaicin from "Pepper" sprays. "CS Gas" was found to persist after exposure for a period of one week. With respect to "Pepper" sprays, the relatively low recovery of the compounds of interest after 72 hours of exposure (almost 50 percent reduction) and their total "loss" after one week highlights the importance of appropriate packaging and timely analysis of such items in casework. The large coefficients of variance determined in the recovery experiments for the analytes of interest in each solvent may be ascribed to the lack of homogeneity of the lachrymator solutions, which may suggest poor solubility of the active substance; the relatively low concentration of the active substances within the lachrymators; and the relatively high concentration of impurities noted in both the "CS Gas" and the "Pepper" sprays. 2 tables and 8 references