Evaluation of a headspace solid-phase microextraction method for the analysis of ignitable liquids in fire debris

Area of Science:

• Forensic Chemistry
• Analytical Chemistry

Background:

• Chemical analysis of fire debris is vital for determining fire origins.
• Detecting ignitable liquids in burnt materials presents analytical challenges.

Purpose of the Study:

• To develop and validate a headspace solid-phase microextraction (HS-SPME) method for detecting ignitable liquids in fire debris.
• To optimize experimental conditions for enhanced extraction efficiency.

Main Methods:

• Utilized a novel HS-SPME fiber coated with Divinylbenzene/Carboxen/Polydimethylsiloxane (DVB/CAR/PDMS).
• Analyzed gasoline and diesel fuel spiked onto a preburnt matrix (wood charcoal) using gas chromatography/mass spectrometry (GC/MS).
• Optimized extraction temperature, incubation, and exposure times.

Main Results:

• The HS-SPME method successfully extracted and concentrated ignitable liquids from burnt matrices.
• The developed procedure was validated using fire debris samples generated in a smoke density chamber and cone calorimeter.
• The method demonstrated suitability for detecting ignitable liquids in highly burnt particleboard and carpet samples.

Conclusions:

• The optimized HS-SPME procedure is effective for identifying ignitable liquids in challenging fire debris samples.
• This method provides a valuable tool for forensic analysis in fire investigations.
• The DVB/CAR/PDMS fiber offers robust performance for detecting common accelerants.