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.

Keywords:

• accelerated solvent extraction (ASE)
• ammunition-contaminated soil
• Energetic compounds
• gas chromatography – microelectron capture detection (GC-µECD)

Disclosure statement

No potential conflict of interest was reported by the authors.

Acknowledgments

We greatly appreciate the assistance provided by the officers and staff officers at the ranges during the field investigation. The valuable assistance with the chemical analysis from Yu Zhao, Yang Yang, and Ying Wang in Shaanxi University of Science and Technology is acknowledged. We are grateful to the editor and three anonymous reviewers whose comments significantly improved the quality of the manuscript.

Additional information

Funding

This work was supported by the Key Research Program of the Chinese Academy of Science (No. KGFZD-135-19-09-02), National Key R&D Program of China (No. 2018YFC1801100), and State Key Laboratory of NBC Protection for Civilian (No. SKLNBC2019-15).