NCJ Number
187621
Journal
Journal of Forensic Sciences Volume: 46 Issue: 2 Dated: March 2001 Pages: 356-362
Date Published
March 2001
Length
7 pages
Annotation
This Australian study tested Cryovac and Globus brand polyethylene/polyvinylidine dichloride bags for their suitability in storing ignitable liquid evidence.
Abstract
The Queensland Police Service and other forensic laboratories in Australia use Cryovac and Globus brand bags to hold evidence that requires ignitable liquid testing. Both manufacturers specify that these bags are made from multi-layer co-extruded polyethylene/polyvinylidine dichloride. In the current study, standards of diesel, kerosene, and gasoline were placed in the bags and sampled by passive headspace adsorption. The bags were then heated to determine whether absorbed components of the standards could be released upon heating. Recovered extracts were analyzed by gas chromatography and gas chromatography mass spectrometry. These bags were found to absorb components of diesel, kerosene, and gasoline and were also found to produce interfering by products that obstruct the chromatographic results. This study shows that the brands of clear plastic bags customarily used in Australian laboratories are unreliable containers for ignitable liquid evidence. Each type of evidence container must be tested to determine whether they affect the analysis of ignitable liquids. 5 figures and 4 references