DI-SPME method for the analysis of fire accelerants in simulated fire debris samples using GC/MS and GC×GC/Q-TOFMS

Area of Science:

• Environmental Chemistry
• Analytical Chemistry
• Forensic Science

Background:

• Climate change exacerbates wildfires, releasing pollutants and necessitating advanced analytical methods for fire debris.
• Traditional headspace solid-phase microextraction (HS-SPME) struggles to detect low-volatility compounds lost during combustion.
• Sustainable and selective analytical techniques are crucial for environmental and forensic fire investigations.

Purpose of the Study:

• To develop and validate a novel analytical method for enhanced fire debris analysis.
• To improve the detection of accelerants in fire debris, addressing limitations of existing techniques.
• To align fire debris analysis with green chemistry principles by minimizing solvent use and analysis time.

Main Methods:

• Direct immersion solid-phase microextraction (DI-SPME) integrated with comprehensive two-dimensional gas chromatography (GC×GC).
• Development of a protective PTFE fiber device to enhance durability and analyte diffusion.
• Analysis of simulated fire debris using GC×GC coupled with quadrupole time-of-flight mass spectrometry (Q-TOFMS).

Main Results:

• The DI-SPME-GC×GC method demonstrated high sensitivity with limits of detection (LOD) ranging from 2.92-85.70 μg L⁻¹.
• Satisfactory intra- and inter-day precision (6.8-25.4%) was achieved for the validated method.
• The novel approach simplifies sample preparation, reduces solvent consumption, and allows for automation and miniaturization.

Conclusions:

• The proposed DI-SPME-GC×GC method provides a reliable and sustainable alternative for accelerant fingerprinting in fire debris analysis.
• This technique enhances forensic and environmental investigations by enabling the detection of crucial analytes previously missed.
• The integration of advanced separation and detection technologies supports more accurate fire investigations.