5.1 TDG is a Schedule 2 compound under the Chemical Weapons Convention (CWC). Schedule 2 chemicals include those that are precursors to chemical weapons, chemical weapons agents, or have a number of other commercial uses. They are used as ingredients to produce insecticides, herbicides, lubricants, and some pharmaceutical products. Schedule 2 chemicals can be found in applications unrelated to chemical weapons. TDG is both a mustard gas precursor and a degradant as well as an ingredient in water-based inks, ballpoint pen inks, dyes, and some pesticides.5

5.2 This method has been investigated for use with soil.

1.1 This procedure covers the determination of thiodiglycol (TDG) in soil using pressurized fluid extraction (PFE). A commercially available PFE system2 is used, followed by analysis using liquid chromatography (LC), and detected with tandem mass spectrometry (MS/MS). TDG is qualitatively and quantitatively determined by this method. This method adheres to single reaction monitoring (SRM) mass spectrometry.

1.2 The method detection limit (MDL) and reporting range for TDG are listed in Table 1.

1.2.1 The MDL is determined following the Code of Federal Regulations, 40 CFR Part 136, Appendix B.

1.2.2 The reporting limit (RL) is calculated from the concentration of the Level 1 calibration standard as shown in Table 4. The RL for this method is 200 ppb. Reporting range concentrations are calculated from Table 4 concentrations assuming a 5 μL injection of the lowest level calibration standard, 5 g sample, and a 2 mL final extract volume.

1.3 Units—The values stated in SI units are to be regarded as standard. No other units of measurement are included in this standard.

1.4 This standard does not purport to address all of the safety concerns, if any, associated with its use. It is the responsibility of the user of this standard to establish appropriate safety, health, and environmental practices and determine the applicability of regulatory limitations prior to use.

1.5 This international standard was developed in accordance with internationally recognized principles on standardization established in the Decision on Principles for the Development of International Standards, Guides and Recommendations issued by the World Trade Organization Technical Barriers to Trade (TBT) Committee.