Environmental markers of chemical warfare agents (CWAs) comprise millions of chemical struc-tures. The simultaneous detection and identification of these environmental markers poses difficultydue to their diverse chemical properties. In this work, by using ultra-high performance liquidchromatography–quadrupole time-of-flight mass spectrometry (UHPLC–QTOF), a generic analyticalmethod for the detection and identification of wide range of environmental markers of CWAs (includingprecursors, degradation and co-products of nerve agents and sesqui-mustards) in drinking water, wasdeveloped. The chromatographic analysis of 55 environmental markers of CWAs including isomeric andisobaric compounds was accomplished within 20 min, using 1.8 m particle size column. Subsequentidentification of the compounds was achieved by the accurate mass measurement of either protonatedmolecule [M+H]+or ammonium adduct [M+NH4]+and fragment ions. Isomeric and isobaric compoundswere distinguished by chromatographic retention time, characteristic fragment ions generated by bothin-source collision induced dissociation (CID) and CID in the collision cell by MS/MS experiments. Theexact mass measurement errors for all ions were observed less than 3 ppm with internal calibration.The method limits of detection (LODs) and limits of quantification (LOQs) were determined in drink-ing water and found to be 1–50 ng mL−1and 5–125 ng mL−1, respectively. Applicability of the proposedmethod was proved by determining the environmental markers of CWAs in aqueous samples providedby Organization for the Prohibition of Chemical Weapons during 34th official proficiency test.© 2014 Elsevier B.V. All rights reserved.