Semivolatile Organics US EPA Method 8270 - Rxi®-5Sil MS

Importance of the Topic

The accurate detection and quantification of semivolatile organic compounds (SVOCs) in environmental and industrial samples is critical for monitoring pollution, ensuring regulatory compliance, and protecting public health. EPA Method 8270D provides a standardized GC-MS approach for a wide range of SVOCs.

Objectives and Study Overview

This application note illustrates the use of a Restek Rxi®-5Sil MS GC column coupled with mass spectrometry to analyze a mixture of SVOCs defined by EPA Method 8270D, evaluating sensitivity, selectivity, and reproducibility across target analytes.

Used Instrumentation

• Gas chromatograph equipped with Rxi®-5Sil MS column (20 m × 0.18 mm ID, 0.36 µm film thickness)
• Mass spectrometer with electron ionization (EI) source, scan range 35–550 amu
• Inlet: 4 mm drilled splitless uniliner; injection at 250 °C, pulsed splitless (20 psi at 0.2 min)
• Carrier gas: helium at constant flow 1.2 mL/min

Key Findings and Discussion

• Chromatographic performance: Baseline separation was achieved for all 93 target and surrogate compounds with sharp, symmetrical peaks.
• Detection limits: On-column injection of 10 ng per compound demonstrated low detection thresholds suitable for trace analysis.
• Reproducibility: Retention time RSDs were under 1%, indicating robust method performance.
• Matrix considerations: Implementing surrogate standards and internal standards ensured accurate quantitation and compensated for potential matrix effects.

Benefits and Practical Applications

• Comprehensive coverage: Ability to analyze a broad spectrum of SVOCs, including phenols, nitrosamines, phthalates, and PAHs.
• Regulatory compliance: Direct applicability to environmental monitoring and QA/QC in water, soil, and waste matrices.
• Flexibility: Column and method parameters can be adapted for faster run times or improved resolution as needed.

Future Trends and Potential Applications

• Integration with high-resolution MS for enhanced selectivity in complex matrices.
• Automation and online extraction techniques to increase throughput and reduce sample handling.
• Expansion to emerging contaminants such as novel flame retardants and transformation products.

Conclusion

The optimized GC-MS workflow using the Rxi®-5Sil MS column for EPA Method 8270D offers reliable, sensitive, and reproducible analysis of semivolatile organics. Adoption of this approach supports robust environmental monitoring and quality control across diverse laboratories.

References

1. US EPA Method 8270D: Semivolatile Organic Compounds by GC-MS.
2. Restek Corporation Application Note: Rxi®-5Sil MS Column Performance Data.