Analysis of 1,4-Dioxane by Extraction and Gas Chromatography/Mass Spectrometry

Poster Presentation

Prepared by N. Abousaeedi1, C. Appleby2, A. Mayo3, Y. Yang4, J. Rest1, E. Mondon-Konan1
1 - CSC, 15000 Conference Center Drive, Chantilly, VA, 20151, United States
2 - EPA OSWER/OSRTI/TIFSD, Analytical Services Branch (ASB), 1200 Pennsylvania Ave., NW, 5104A Ariel Rios Building/Room B452, Washington, DC, 20460, United States
3 - CSC, 6361 Walker Lane, Alexandria, VA, 22310, United States
4 - CSC, 6361 Walker Lane, Alexandria, VA, 22310, United States


Contact Information: [email protected]; 703-818-4233


ABSTRACT

1,4-Dioxane is included as a target analyte in United States Environmental Protection Agency (U.S. EPA) SW-846 Method 8260B, Volatile Organic Compounds by Gas Chromatography/Mass Spectrometry, with purge-and-trap as one of the preparation techniques. Under the U.S. EPA Contract Laboratory Program (CLP) Statement of Work (SOW) for Organics Analysis (Multi-Media, Multi-Concentration) SOM01.2, 1,4-Dioxane is also analyzed as a volatile target analyte, by purge-and-trap and Gas Chromatography/Mass Spectrometry (GC/MS), but at the relatively high Contract Required Quantitation Limits (CRQLs) of 100 ug/L and 100 ug/kg for aqueous and soil matrices, respectively. Due to its poor purging efficiency at the conditions specified in the SOM01.2 SOW, 1,4-Dioxane has presented very low Relative Response Factors (RRFs) in the initial and continuing calibration standards that often fail to meet the technical acceptance criteria. Consequently, the analyte results in the field samples have to be deemed unusable.

In order to meet the regulatory requirements for 1,4-Dioxane in site studies, demands for lowering its quantitation limits and improving data usability have resulted in a series of efforts on the development of a comprehensive analysis through CLP Modified Analysis (MA) requests. With extraction preparation methods common to semivolatile analytes along with the addition of the deuterated monitoring compound 1,4-Dioxane-d8, field samples have been analyzed through these modified analyses for a number of years, and considerable data pertaining to instrument calibration standards and field samples have been collected. Based on the results obtained from these modified analyses, 1,4-Dioxane has now been successfully included as a semivolatile target analyte with CRQLs of 2.0 ug/L and 67 ug/kg for aqueous and soil matrices, respectively, in the SOM02.2 SOW.