Detection of TNT-Contamination in spiked soil samples using SPME and GC/MS

Soil-contamination from toxic explosive residues at military bases throughout the world, is a major
environmental concern. A strong candidate for TNT soil-contamination within Greece, is the military
base/airport of Maleme in Crete. While soil sampling was in progress new routes of trace analysis for
explosives in soil were explored. Solid-phase micro-extraction (SPME) was used to selectively preconcentrate
analytes prior to GC/MS. In the preliminary experiments (effectuated on water-spiked samples)
optimization of the SPME technique was achieved by controlling parameters such as sampling
method, salt content and sample agitation. As immersion of the SPME fiber was found to be more efficient
for extracting most analytes of interest, a pretreatment step was introduced for the soil samples
which simply converted them to water samples. The developed SPME protocol was able to screen
explosives in spiked-soils, in concentrations well below the certified reporting and detection limits.