Determination of Energetic Compounds in Ammunition Contaminated Soil by Accelerated Solvent Extraction (ASE) and Gas Chromatography – Microelectron Capture Detection (GC-µECD)

Abstract

An analytical method of accelerated solvent extraction combined with gas chromatographic – microelectron capture detection (GC-μECD) was developed for the determination of energetic compounds (ECs) in soils from Chinese ammunition-contaminated sites. The results showed that the recoveries of most compounds were 82.86 ± 7.35 − 109.70 ± 10.82%, 82.53 ± 6.18 − 99.21 ± 1.88%, 80.44 ± 1.73 − 108.20 ± 4.58% at spiked levels of 20, 100, and 500 ng, respectively. Each spiked level was analyzed in triplicate with relative standard deviations from 3.51 to 13.34%, 1.90 to 10.51%, and 0.50 to 5.90%. GC-μECD is highly sensitive to these electronegative compounds with method detection limits (MDL) from 0.64 to 3.48 ng·g−1. This technique has the advantages of high efficiency, reduced solvent consumption, low detection limits, and suitability for a wide range of compounds. The developed approach was successfully applied to the determination of energetic compounds in soils collected from four ammunition-contaminated sites in China. The concentrations of energetic compounds in soil were from 5.60 to 9.22 × 105 ng·g−1 at these sites. The results show that the present method accurately simultaneously determined multiple energetic compounds that may assist with the characterization of soil pollution.