Semi-Volatiles in Drinking Water per EPA Method 525: Maintaining Optimal Analytical Performance

Oral Presentation

Prepared by A. Smith Henry1, V. Abercrombie2, R. Ciotti1, C. Marvin1
1 - Agilent Technologies, 2850 Centerville Road, Wilmington, DE, 19808, United States
2 - Agilent Technologies, 91 Blue Ravine Road, Folsom, CA, 95630, United States


Contact Information: angela.smith@agilent.com; 302-636-8252


ABSTRACT

Drinking water analysis by EPA 525 covers a broad range of organic compound types from polyaromatic hydrocarbons to select pesticides, semivolatile organic compounds and even multicomponent analysis of arochlors and chlordane. The compounds cited in the EPA methods exhibit a wide range of analyte polarity, volatility, and stability and can be a challenge to analyze. Gas chromatography with mass selective detection (GC/MSD) is a crucial technique for quantifying many of these contaminants based on the technique’s sensitivity and selectivity. Additionally, some states have lowered reporting limits and require a larger calibration range to include 0.02 ng/?L as a low-level standard. This study tests the ability of the GC/MSD to calibrate over an extended range of 0.02 to 15 ng/?L and comply with the EPA 525 method. The GC/MSD was also qualified with an extended lifetime test for endrin and DDT breakdown to stress the Ultra Inert flow path. Results exhibit the benefits of the GC/MSD, Ultra Inert flow path and larger extraction lens with the abilities to hold low endrin and DDT breakdown percentages throughout an extended lifetime test, and to extend the linear range for all studied compounds, while retaining sufficient sensitivity for detection of most low-level standards and fulfilling the calibration requirements specified in the drinking water methods.