Versatile Options for Extending Analyte Range and Sensitivity for Monitoring Volatile Organic Compounds (VOCs) in Water and Soil by Automated, Cryogen-free Headspace– and SPME–trap with GC–MS

New Organic Monitoring Techniques
Oral Presentation

Presented by E. Hachmeister
Prepared by R. Szafnauer1, J. Mayser2, E. Hachmeister3, L. Hearn1, S. Smith1, H. Calder1
1 - Markes International, 1000B CENTRAL PARK, WESTERN AVENUE, Bridgend, Non-US, CF31 3RT, United Kingdom
2 - Markes International GmbH, Bieberer Straße 1–7, Offenbach am Main, non-US, 63065, Germany
3 - Markes International Inc., 2355 Gold Meadow Way, Gold River, Sacramento, California, 95670, United States

Contact Information: [email protected]; 01443230935


Water is one of the most heavily regulated substances globally. Governmental bodies are tasked with ensuring water quality is upheld with various environmental monitoring laws in place to protect against a diverse range of anthropogenic and naturally-occurring chemicals. Monitoring for volatile organic chemicals in water is vital due their potential role in global climate and negative impacts on human health, even when present at trace levels. Similarly, soils are fundamental to a variety of ecosystem functions, and so monitoring soil health is also essential.
To identify and quantify these chemicals US EPA Methods 524, 624 and SW-846 Test Methods are commonly applied to drinking water, wastewaters and soil, respectively, using purge-and-trap (P&T) technology. However, syringe-based headspace and solid-phase microextraction techniques, combined with temperature-controlled trap focusing are alternative, yet similarly robust, techniques offering several practical advantages over P&T, namely compatibility with disposable vials and avoidance of problems associated with foaming and aerosol formation.
Here, we demonstrate sensitive, quantitative detection of a wide volatility range of VOCs in water samples that is ideal for high throughput laboratories, and the potential for applying this method to soil samples. We show how using an electrically-cooled focusing trap with appropriate sorbent packing provides excellent chromatographic performance and sensitivity, while avoiding issues relating to P&T, and the cost and inconvenience of cryogen (including the associated risk of ice blockages) that is used with alternative thermal desorption systems. Low ppb (µg/L) to low ppt (ng/L) detection is achieved in wastewater and drinking water samples, respectively and the discovery of more compounds in soil samples was enabled by the multi-step enrichment capability of the trap, further allowing simple sample preparation while enhancing the quality of data produced. Finally, we show the performance of Markes’ sample re-collection technology for facilitating repeat analysis of samples without needing a new sample.