27 Sep 2021

Methods for Simultaneous Determination of 29 Legacy and Insensitive Munition (IM) Constituents in Aqueous, Soil-Sediment, and Tissue Matrices by High-Performance Liquid Chromatography (HPLC)

Abstract: Standard methods are in place for analysis of 17 legacy munitions compounds and one surrogate in water and soil matrices; however, several insensitive munition (IM) and degradation products are not part of these analytical procedures. This lack could lead to inaccurate determinations of munitions in environmental samples by either not measuring for IM compounds or using methods not designed for IM and other legacy compounds. This work seeks to continue expanding the list of target analytes currently included in the US Environmental Protection Agency (EPA) Method 8330B. This technical report presents three methods capable of detecting 29 legacy, IM, and degradation products in a single High Performance Liquid Chromatography (HPLC) method with either ultraviolet (UV)-visible absorbance detection or mass spectrometric detection. Procedures were developed from previously published works and include the addition of hexahydro-1-nitroso-3,5-dinitro-1,3,5-triazine (MNX); hexahydro-1,3-dinitroso-5-nitro-1,3,5-triazine (DNX); hexahydro-1,3,5-trinitroso-1,3,5-triazine (TNX); 2,4-diamino-6-nitrotoluene (2,4-DANT); and 2,6-diamino-4-nitrotoluene (2,6-DANT). One primary analytical method and two secondary (confirmation) methods were developed capable of detecting 29 analytes and two surrogates. Methods for high water concentrations (direct injection), low-level water concentrations (solid phase extraction), soil (solvent extraction), and tissue (solvent extraction) were tested for analyte recovery of the new compounds.

30 Jul 2020

PUBLICATION NOTICE: Environmental Analysis of Aqueous 3-Nitro-1,2,4-Triazol-5-One (NTO) by Ion Chromatography with Conductivity Detection

Abstract:  The newly fielded insensitive high-explosive compound 3-nitro-1,2,4-triazol-5-one (NTO) is mobile in the environment due to its high water solubility and low affinity for soils. The weak acidity of NTO (pKa 3.67) presents a challenge to environmental analysis by high-performance liquid chromatography but enables direct separation by ion chromatography (IC). Here we developed an IC method for NTO in natural water, soil, and postdetonation residue. A gradient potassium hydroxide separation effectively resolved the inorganic anions (F−, Cl−, NO2−, Br−, SO42−, NO3−, and PO43−) and NTO in 18 minutes. Suppressed conductivity of aqueous NTO was linear from 10 µg/L to 10 mg/L with a detection limit of 3 µg/L and quantitation limit of 9 µg/L. Recoveries of NTO-spiked natural water samples were 93%–118% at concentrations of 30, 100, and 500 µg/L. Recoveries of NTO-spiked soil samples were 91%–114% using deionized water (DI) extraction. NTO was completely recovered with DI-extraction in two postdetonation residue samples of IMX-101 but only partially recovered (58% and 69%) in two higher-concentration residues, potentially due to incomplete dissolution of the energetic particle matrix. These results support IC for confirmation analysis of environmental samples and for screening natural water samples while simultaneously analyzing inorganic ions.