US EPA Method 524.2: Software Tools for Successful Method Development and Analysis of Purgeable Organic Compounds in Drinking Water

Drinking Water
Oral Presentation

Prepared by A. Andrianova, B. Quimby
Agilent Technologies, 2850 Centerville Rd., Wilmington, DE, 19808, United States


Contact Information: anastasia.andrianova@agilent.com; 302-636-3969


ABSTRACT

Volatile organic compounds (VOCs) were successfully measured in drinking water over the calibration range of 0.25-50 µg/L using a GC/MS system coupled with a purge-and-trap (P&T) concentrator. The software tools described in this work offer simple and rapid means to streamline quantitation method development, data processing, and reporting via the following steps:
• A VOC standard was analyzed and the deconvoluted spectra were searched against the NIST spectral library for compound identification
• A user library was created. It included the identified compounds with their retention times and deconvoluted spectra
• A quantitation method was created from the user spectral library using the compound information and retention times included in the library.
• Real-world samples were analyzed with the quantitation method. Spectral deconvolution enabled in the method allowed for confirmation of compound identifications. The concentration of the VOCs in the real-world sample was determined against the initial calibration.

The analytical method used a targeted BFB Autotune, which provides high sensitivity and stability, while maintaining the required ion abundance ratios in the BFB spectrum. Calculated MDLs were in ppt levels, which is typical using the conditions of this analysis. Several VOCs were identified and confirmed via spectral deconvolution in the real-world drinking water samples. The quantified concentrations varied over the range of 0.3 to 14.1 µg/L that is much lower than current EPA 524.2 MDLs.