The United Nations Chemical Weapons Convention (CWC) prohibits the production, stockpiling and use of chemical weapons. Reliable analytical methods for the identification of chemicals relevant to the CWC will be required to assist in the verification of the treaty. Positive and negative ion electrospray mass spectra (ESMS) were obtained for CWC related chemicals directly from water/solvent solutions. ESMS was used to successfully screen for the relevant chemicals in water extracts of soils that had previously been spiked with a mixture of nerve agent and mustard gas degradation products. Tandem Mass Spectrometry (MS/MS) was used to positively identify the spiking chemicals. ESMS may provide a fast screening technique for CWC related chemicals through direct analysis of aqueous extracts of environmental samples.