A solid-phase microextraction method for the detection of ignitable liquids in fire debris.

Area of Science:

• Forensic Science
• Analytical Chemistry

Background:

• Accelerant detection in fire debris is crucial for arson investigation.
• Traditional methods can be time-consuming or require complex sample preparation.

Purpose of the Study:

• To develop and evaluate a direct contact solid-phase microextraction (SPME) method for accelerant detection in fire debris.
• To compare the performance of different SPME fibers for extracting ignitable liquids.

Main Methods:

• Investigated six different SPME fibers (polydimethylsiloxane, polydimethylsiloxane-divinylbenzene, polyacrylate, carboxen-polydimethylsiloxane, Carbowax-divinylbenzene, divinylbenzene-Carboxen-polydimethylsiloxane).
• Evaluated direct contact SPME by immersing fibers into gasoline, kerosene, and diesel fuel.
• Applied the direct contact SPME method to simulated fire debris packed in plastic bags, analyzing with gas chromatography/mass spectrometry.

Main Results:

• The direct contact SPME method demonstrated comparable results to headspace SPME for gasoline and kerosene extraction.
• This method showed improved recovery of low-volatile components for diesel fuel extraction from fire debris.
• Successful detection of accelerants was achieved using SPME fibers in direct contact with the fire debris matrix.

Conclusions:

• Direct contact SPME is a simple and rapid screening method for detecting ignitable liquids in fire debris.
• The procedure is suitable for analyzing fire debris samples packed in plastic bags.
• This technique offers a viable alternative for accelerant analysis in forensic investigations.