The first comprehensive assessment of 34 solid phase extraction sorbents is presented for organic explosive residues in wastewater prior to analysis with liquid chromatography-high resolution accurate mass spectrometry (LC-HRMS). A total of 18 explosives were selected including nitramines, nitrate esters, nitroaromatics and organic peroxides. Three polymeric divinylbenzene-based sorbents were found to be most suitable and one co-polymerised with n-vinyl pyrrolidone offered satisfactory recoveries for 14 compounds in fortified wastewater (77-124%). Limits of detection in matrix ranged from 0.026-23μgL with R≥0.98 for most compounds. The method was applied to eight 24-h composite wastewater samples from a London wastewater works and one compound, 2,4-dinitrotoluene, was determined over five days between 332 and 468g day (225-303ngL). To further exploit the suspect screening capability, 17 additional explosives, precursors and transformation products were screened in spiked wastewater samples. Of these, 14 were detected with recoveries from 62 to 92%, highlighting the broad applicability of the method. To our knowledge, this represents the first screen of explosives-related compounds in wastewater from a major European city. This method also allows post-analysis detection of new or emerging compounds using full-scan HRMS datasets to potentially identify and locate illegal manufacture of explosives via wastewater analysis.

This article presents solid phase extraction (SPE) and liquid chromatography-mass spectrometry (LC-MS) methods for the trace detection of the peroxide explosives triacetone triperoxide (TATP) and hexamethylene triperoxide diamine (HMTD). Furthermore, experimental studies use these methods to explore the efficiency of wastewater treatment plant (WWTP) processes at removing trace levels of peroxide explosives from water samples to assess the application of the developed methods for the detection of explosives in the environment. The principal results of this study showed that the greatest removal of TATP and HMTD from spiked water samples occurred following the biological treatment stage, however, the WWTP processing did not completely remove all of the analytes from the water, suggesting that such chemicals could contaminate downstream river water samples. The toxicity of chemical pollutants is often determined by their concentration, however, even at trace levels, the monitoring of explosives in the natural environment could be extremely informative for the detection of criminal activity as well as long-term effects upon aquatic life. These findings also have significant implications for crime prevention and disruption approaches that can use this type of data as intelligence to guide investigations regarding the source and attribution of detected explosives.