SPME for the determination of volatile organic compounds in water: Results from global interlaboratory trial for validation of new ISO 17943

Importance of the Topic

Volatile organic compounds (VOCs) are widespread contaminants in water arising from petroleum products, solvents, paints and industrial processes. Many VOCs pose acute toxicity risks and are suspected human carcinogens, making their monitoring critical for environmental safety and public health. Compliance with stringent regulations such as the EU Drinking Water Directive and the US Safe Drinking Water Act demands sensitive, reliable analytical methods.

Objectives and Study Overview

This work describes the expansion and validation of the German DIN 38407-41 standard into the new international ISO 17943 method. The aims were to extend the target list from 25 to 63 VOCs, include surface, ground, drinking and wastewater matrices, and demonstrate method performance through a global interlaboratory trial involving spiked surface water and municipal wastewater samples.

Methodology and Instrumentation

Headspace solid-phase microextraction (HS-SPME) was employed for sample preparation. A 10 mL water aliquot was salted and equilibrated at 40 °C before extracting VOCs for 10 minutes using a DVB/CAR/PDMS fiber. Desorption occurred in a heated injector at 270 °C for 10 minutes. Gas chromatographic separation was performed on a 60 m VOCOL capillary column with helium carrier gas, using a temperature program from 35 °C to 250 °C. Mass spectrometric detection provided selective quantification.

Instrumentation Used

• SPME Fiber: DVB/CAR/PDMS, 24 gauge
• Autosampler: CTC Combi PAL with agitation
• Gas Chromatograph: Varian CP-3800
• Column: VOCOL, 60 m × 0.25 mm × 1.5 µm
• Mass Spectrometer: Single-quadrupole GC/MS detector

Main Results and Discussion

Out of 42 laboratories invited, 27 adhered to the protocol and provided valid data under ISO 5725-2. Recovery rates ranged from 81 % to 118 % across most analytes. Reproducibility standard deviations were below 35 % and repeatability below 10 % for the majority of compounds. These results confirm method robustness and suitability for routine regulatory monitoring.

Benefits and Practical Applications

The standardized HS-SPME-GC/MS approach offers significant advantages including solvent‐free sample preparation, high sensitivity (LODs <0.01 µg/L), and simplified automation. Laboratories can reliably monitor a broad spectrum of VOCs in diverse water matrices, supporting compliance and quality control in environmental and industrial settings.

Future Trends and Potential Applications

Advances may include enhanced fiber coatings for ultra-volatile or polar compounds, integration with two-dimensional GC for complex mixtures, and coupling to high-resolution mass spectrometry for non-target screening. Broader adoption in wastewater treatment, groundwater remediation assessments, and emerging contaminant monitoring is anticipated.

Conclusion

The global interlaboratory trial successfully validated the expanded ISO 17943 method for 63 VOCs in water. The method demonstrates excellent accuracy, precision and reproducibility, and is poised for international publication and routine implementation.

Reference

• Council Directive 98/83/EC on drinking water quality
• Directive 2000/60/EC establishing a framework for water policy
• Decision 2455/2001/EC concerning pollutant release
• US Safe Drinking Water Act (SDWA)