The detection and analysis of ignitable liquid residues extracted from human skin using SPME/GC

A simple, fast, inexpensive, and sensitive technique for the detection and identification of flammable or combustible liquid residues on the skin of arson suspects is presented. The use of solid phase microextraction (SPME) for the analysis of ignitable liquid residues has been demonstrated and it is shown in this work that this technique is effective in extracting these liquid residues at extremely low quantities. Microliter quantities of controlled spikes of gasoline, diesel fuel, and charcoal lighter fluid were deposited on the hands of a volunteer and extracted after several time intervals. The SPME technique can recover very small amounts of liquid deposits on skin up to 3.5 h after exposure, depending on the class of the ignitable liquid residue used.