USEPA 8260D Determination Using the New Evolution 2 Purge and Trap Concentrator

Importance of the Topic

This application note addresses the need for sensitive and reliable analysis of volatile organic compounds in environmental water and soil samples. Efficient purge and trap concentration coupled with gas chromatography mass spectrometry is critical for regulatory compliance, pollution monitoring, and quality control in industrial and research laboratories.

Objectives and Overview of the Study

The study evaluates the performance of the EST Analytical Evolution 2 purge and trap concentrator under USEPA Method 8260D. Key goals include assessing calibration linearity, precision, detection limits, carryover effects, and internal standard stability in both water and soil matrices.

Methodology

A Vocarb 3000 trap was conditioned and installed in the Evolution 2 concentrator. Automated sampling of water and soil extracts was performed with a Centurion WS autosampler. Target analytes were purged from the samples at 40 mL/min for 11 minutes, followed by controlled desorption into a gas chromatograph equipped with a Rxi 624Sil MS column. Mass spectrometric detection scanned m/z 35 to 300. Studies included:

• Nine-point calibration from 0.5 to 200 µg/L
• Method detection limit determination over three days
• Precision and recovery at 50 µg/L in seven replicates
• Internal standard stability across 30 blanks
• Carryover assessment after 50 and 200 µg/L injections

Instrumentation Used

• EST Analytical Evolution 2 purge and trap concentrator with moisture reduction trap
• Vocarb 3000 trapping material
• EST Analytical Centurion WS autosampler
• Gas chromatograph with Rxi 624Sil MS column (30 m x 0.25 mm id x 1.4 um film)
• Mass spectrometer in scan mode (m/z 35–300)

Main Results and Discussion

The system demonstrated excellent performance under EPA 8260D criteria:

• Calibration linearity showed RSD below 15% across all compounds
• Method detection limits met target values for water and soil samples
• Precision at 50 µg/L averaged under 5% RSD with mean recoveries around 95%
• Internal standards exhibited stability below 2% RSD over sequential blank runs
• Carryover was minimal, averaging below 0.3% after both 50 and 200 µg/L standards

Benefits and Practical Applications

The Evolution 2 concentrator offers:

• Reduced footprint and improved laboratory ergonomics
• Enhanced moisture control and reduced analyte carryover
• Faster cycle times through advanced air circulation
• User-friendly software interface for routine operation

These features support high-throughput environmental monitoring, QA/QC in drinking water analysis, and soil contamination studies.

Future Trends and Potential Applications

Emerging developments may include integration with laboratory information management systems, remote operation and diagnostics via network connectivity, novel sorbent materials for broader analyte ranges, and miniaturized concentrators for field deployment. Advances in AI-driven data analysis could further enhance method robustness and throughput.

Conclusion

The EST Analytical Evolution 2 purge and trap concentrator, combined with the Centurion WS autosampler, meets all USEPA 8260D requirements for volatile organic compound analysis in water and soil. Its improved design and performance deliver reliable, accurate, and efficient workflows for environmental and industrial laboratories.

References

United States Environmental Protection Agency Method 8260D Revision 4 June 2018