Rapid Trace Analysis of Synthetic Pyrethroids in Stormwater Using online preconcentration followed by Liquid Chromatography-Tandem Mass Spectrometry

Date / Time:
Tuesday, Sep 16 2:40pm to 3:10pm
Garden 3
Track / Session:

Synthetic pyrethroids (SPs) are a class of pesticides for which there is an emerging concern, particularly in urban areas. Because certain SPs are written into NPDES permits, this requires a laboratory that is capable of performing this analysis while meeting certain data quality objectives. This also may require that laboratories provide reporting limits that are at or below concentrations for which SPs are toxic to sensitive aquatic fauna. Toxicity studies of SPs have produced a wide range of toxic concentrations and, in a few cases, these toxicity levels require the ability to detect SPs at a level that commercial laboratories may find difficult to acheive. Currently, most analytical methods for SPs used by laboratories involve either a solid phase extraction (SPE) or continuous liquid-liquid extraction (CLLE) followed by gas chromatography-mass spectrometry (GC-MS). Currently, the most sensitive GC-MS technique uses electron capture chemical ionization (ECNI) commonly referred to as negative chemical ionization (NCI). Because GC techniques require a heated injection port during analysis, the ability to detect SPs at lower levels introduces additional challenges. Specifically that some SPs like Tralomethrin absorb or breakdown at such low concentrations and high temperatures.

With these challenges in mind, a method was developed to increase sample throughput, sensitivity, selectivity, and robustness. This method requires one 40mL VOA vial which provides enough volume to analyze the sample and a matrix spike/duplicate (MS/MSD). The benefits of this are reduced shipping costs, increased sample throughput, and reducing the labor required to extract 1 liter of sample. Reporting limits, method detection limit study data, and matrix spike data are presented for this method and are compared with data quality produced by a continuous liquid-liquid extraction followed by the same LC-MS-MS analysis.

Primary Speaker:
David Schiessel, Babcock Laboratories, Inc.
David Schiessel has been the senior chemist in the Semi-Volatiles department at Babcock Laboratories for 2.5 years and has been working as a chemist in environmental laboratories for about 12 years. He has spent a considerable amount of time optimizing and developing analytical methods for organics analyses. He is proficient in the routine instrumental analysis of water, soil, and air including the use of gas chromatography, liquid chromatography, mass spectrometry, tandem mass spectrometry, and post-column derivatization. He is currently the Babcock Laboratories' primary analyst for the analysis of emerging contaminants as well as UCMR3 methods for 1,4-dioxane, perflourinated organic acids, and hormones. He has a passion for using analytical instrumentation to solve new environmental challenges and to develop analytical methods that meet data quality objectives for the clients of Babcock Laboratories.