NCJ Number
146656
Journal
Journal of Forensic Sciences Volume: 39 Issue: 1 Dated: (January 1994) Pages: 186-193
Date Published
1994
Length
8 pages
Annotation
A method for analyzing trace levels of gasoline in arson debris using an automatic thermal desorber (TD) and commercial Tenax adsorbent tubes is described.
Abstract
A static headspace screening test is performed by gas chromatography using a flame ionization detector (GC-FID). Suspected gasoline is reanalyzed by gas chromatography-mass spectrometry (GC-MS). Gasoline traces smaller than 10 mL in a 1-liter volume are analyzed by a dynamic heated headspace procedure with thermal desorption and GC-MS after adsorption on 45-mg Tenax tubes. The desorption of adsorbed vapors is carried out by heating tubes; analytes are focused in cryogenic units cooled with liquid nitrogen. The cryofocused vapor sample is flash-heated for injection into the GC capillary column. Case examples show that the dynamic heated headspace technique (TD-GC-MS) is suitable for analyzing trace amounts of gasoline. 5 references, 3 tables, and 6 figures