Analysis of VOCs according to EPA Method 8260

Significance of the topic

Volatile organic compounds (VOCs) are pervasive environmental contaminants arising from industrial processes, petroleum products, pharmaceuticals, and consumer goods. They pose significant health risks at elevated levels, making accurate monitoring in water and soil critical for regulatory compliance and public safety.

Study objectives and overview

This application note presents an integrated analytical workflow designed to meet U.S. EPA Method 8260D requirements for the quantitation of purgeable organic compounds in wastewater and soil. Key performance metrics—including calibration linearity, method detection limits (MDLs), precision, accuracy, and robustness—are systematically assessed.

Methodology and instrumentation

Sample preparation and standards:

• Calibration standards covering 0.2–200 ppb in water and 1–200 ppb in soil, prepared from Restek mixtures.
• Internal standards (pentafluorobenzene, 1,4-difluorobenzene, chlorobenzene-d5, 1,4-dichlorobenzene-d4) and surrogates (dibromofluoromethane, 1,2-dichloroethane-d4, toluene-d8, 4-bromofluorobenzene) spiked at 25 ppb.

Instrumental analysis:

• Purge and trap: Teledyne Tekmar Atomx XYZ using EPA Methods 5030/5035 with optimized temperatures, gas flows, and trapping conditions for water and soil.
• Gas chromatography and mass spectrometry: Thermo Scientific TRACE 1310 GC equipped with a TraceGOLD TG-VMS column (20 m×0.18 mm, 1 µm) coupled to the Thermo Scientific ISQ 7000 single quadrupole MS (NeverVent vacuum probe interlock, ExtractaBrite ion source) in selected ion monitoring mode.
• Software control and data processing: Chromeleon CDS v7.2 orchestrates sample sequence, data acquisition, quantitation, and reporting within a unified eWorkflow.

Main results and discussion

Chromatography and identification:

• Baseline separation of >100 VOCs with consistent peak shapes in both water and soil matrices.
• Mass spectral matching to NIST library confirms compound identity with high spectral fidelity.

Linearity and sensitivity:

• Calibration curves over 0.2–200 ppb (water) and 1–200 ppb (soil) achieved R² > 0.99 and response factor RSD < 20%.
• Calculated MDLs < 0.25 ppb in water and < 0.53 ppb in soil for most target analytes.

Precision and accuracy:

• Seven replicates of 20 ppb matrix-matched standards yielded RSD < 20% and recoveries within ±30%, fulfilling Initial Demonstration of Capability criteria.

Robustness:

• Continuous acquisition of 240 water injections over three days without user intervention produced mean recovery ~90% and overall RSD ~8.3%, demonstrating long-term stability.

Benefits and practical applications

• Modular GC-MS design and never-vent ion source reduce downtime and simplify maintenance.
• Efficient trap cooling and moisture control enhance throughput and column lifetime.
• Unified software control streamlines method setup, reduces human error, and ensures data traceability.
• Compliance with EPA Method 8260D supports environmental laboratories in routine VOC monitoring of wastewater, groundwater, and solid matrices.

Future trends and opportunities

Advancements in instrument automation and eWorkflows will further reduce setup time and training requirements. Expanding the method to cover emerging VOCs, adapting to high-throughput screening needs, and integrating real-time data analytics are promising directions. Implementation of alternative sorbent materials and miniaturized P&T systems may enhance sensitivity and portability for field applications.

Conclusion

The combination of the Teledyne Tekmar Atomx XYZ purge-and-trap system with the Thermo Scientific TRACE 1310 GC and ISQ 7000 MS delivers a robust, sensitive, and high-throughput solution that satisfies all performance requirements of U.S. EPA Method 8260D for VOC analysis in water and soil. The workflow offers reliable linearity, low detection limits, reproducible precision, and seamless operation under automated control.

Instrumentation used

• Teledyne Tekmar Atomx XYZ purge-and-trap concentrator
• Thermo Scientific TRACE 1310 gas chromatograph with TraceGOLD TG-VMS column
• Thermo Scientific ISQ 7000 single quadrupole mass spectrometer (NeverVent VPI, ExtractaBrite source)
• Chromeleon CDS v7.2 software and AppsLab eWorkflow

References

• U.S. Environmental Protection Agency. Method 8260D: Volatile Organic Compounds by Gas Chromatography/Mass Spectrometry, March 2017.
• Thermo Scientific AppsLab: EPA Method 8260D eWorkflow for Chromeleon CDS.
• Thermo Scientific Application Note 65632: Routine analysis of volatile organic compounds in drinking water with ISQ 7000 GC-MS.