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

Importance of Topic

The analysis of semivolatile organic compounds (SVOCs) is vital for environmental monitoring, food safety, industrial quality control and regulatory compliance. US EPA Method 8270 provides a standardized approach to detect and quantify a broad range of SVOCs, including polycyclic aromatic hydrocarbons (PAHs), chlorinated phenols, nitroaromatics and phthalates. Reliable GC–MS separation of complex mixtures ensures accurate identification of trace-level contaminants in soil, water and other matrices.

Objectives and Study Overview

This application note demonstrates the performance of a Restek Rtx®-5Sil MS column for EPA Method 8270 analysis. The goals are to verify resolution of key benzo(b)fluoranthene/benzo(k)fluoranthene isomers, assess retention time reproducibility for 106 target analytes, and illustrate a robust oven temperature program and splitless injection protocol for trace-level sensitivity.

Methodology and Instrumentation

A mixture of 106 semivolatile standards was injected (80 ng each) under the following conditions:

• Column: Rtx®-5Sil MS (30 m × 0.25 mm ID × 0.5 µm film, silarylene phase)
• Injection: Splitless, 300 °C injector temperature
• Carrier Gas: Helium at 1.0 mL/min constant flow
• Oven Program: 40 °C hold 2 min → 290 °C @ 20 °C/min → 303 °C @ 2 °C/min → 330 °C @ 6 °C/min, final hold 1 min
• Detector: MSD at 280 °C, scan range 35–550 amu
• GC Instrument: Agilent 6890 coupled to mass spectrometer

Main Results and Discussion

The chromatogram showed baseline separation of critical isomers, notably benzo(b)fluoranthene (peak 99) and benzo(k)fluoranthene (peak 100). Early eluting nitrosamines and small phenols were resolved without coelution. Mid-range chlorinated benzenes and phenols exhibited sharp peaks with minimal tailing. Late-eluting PAHs and high-molecular-weight polynuclear compounds produced reproducible retention times and mass spectra. Overall, the Rtx®-5Sil MS column provided high inertness, excellent peak shape and consistent performance across all compound classes.

Benefits and Practical Applications

Implementing this method offers:

• Robust identification and quantitation of over 100 SVOCs in a single run
• High sensitivity suitable for regulatory limits and trace-level monitoring
• Reproducible retention times to support database matching and quality assurance
• Versatility across environmental, food, petrochemical and consumer product testing

Future Trends and Potential Uses

Advances in GC–MS instrumentation, such as higher-resolution mass spectrometers and multidimensional GC, will further improve separation of complex mixtures. Coupling with automated sample preparation (e.g., SPME, automated SPE) can increase throughput. Emerging regulatory needs for novel SVOCs, including brominated flame retardants and per- and polyfluoroalkyl substances (PFAS), may be addressed by extending the EPA 8270 target list.

Conclusion

The described configuration delivers reliable, high-resolution analysis of semivolatile organics per EPA Method 8270. The Rtx®-5Sil MS column in combination with Agilent GC–MS instrumentation achieves excellent peak shapes, critical isomer separations and trace-level sensitivity. This method supports diverse analytical needs from environmental compliance to industrial quality control.

References

No external literature references were provided in the original text.