EPA Methods 8270 and 625- Scaled Down Solid Phase Extraction Method for 100mL Samples or Less

Poster Presentation

Prepared by X. Wang, B. Kinsella
UCT, 2731 Bartram Rd, Bristol, PA, 19007, United States


Contact Information: xwang@unitedchem.com; 1-215-781-9255


ABSTRACT

The EPA is updating methods 8270 (8270E) and 625 (625.1) to both now permit the use of solid phase extraction (SPE) for the analysis of semi-volatile organic compounds (SVOCs) in aqueous samples and TCLP leachates. The revised methods will also allow more sensitive and selective instrumentation for analyte detection and quantitation, such as GC-MS with large volume injection (e.g. PTV), GC-MS in SIM mode, ion trap MS, and tandem MS. As a result of these enhanced technological advancements, smaller sample sizes can now be utilized to obtain required method detection limits, in turn reducing solvent and standard consumptions and overall sample preparation time.

This poster will present a reliable, efficient, and cost-effective SPE method utilizing tandem stacked cartridges for the extraction of 100 mL water samples or less. The upper EC8270 cartridge retains the majority of the target analytes including acids, bases, and neutrals with mid to high hydrophobicity, while the carbon cartridge connected downstream will capture more polar compounds, such as 1,4-dioxane, n-nitrosodimethylamine, n-nitrosomethylethylamine, methyl methanesulfonate, ethyl methanesulfonate, and 1-Nitrosopyrrolidine. For further simplification, the methodology can be executed with the EC8270 cartridges alone for TCLP samples, as the TCLP list of SVOCs, pesticides, and herbicides does not contain any of the more polar compounds listed above that necessitate the use of the carbon cartridges.

High sample throughput can be achieved by extracting 16 samples simultaneously with a 16-port glass block vacuum manifold. The overall means of the recovery and RSD% for 4 replicated spiked samples were 87.2% and 2.5% for a total of 125 compounds.