US EPA Method 524.2 with the Teledyne Tekmar Lumin P&T Concentrator and PerkinElmer® Clarus® 600 GC/Clarus® SQ8T MS

Importance of the Topic

US EPA Method 524.2 is widely applied for trace analysis of volatile organic compounds in drinking water by purge and trap GC/MS. Excess water vapor transfer challenges system stability, column performance, and requires frequent maintenance. The Teledyne Tekmar Lumin concentrator’s Moisture Control System (MCS) addresses these issues by reducing water load and enabling higher sample throughput.

Objectives and Study Overview

This application study evaluates the combined performance of the Lumin P&T concentrator with AQUATek 100 and a PerkinElmer Clarus 600 GC/Clarus SQ8T MS under EPA Method 524.2. Key goals include assessing water vapor removal, detection limits, calibration linearity, accuracy, precision, and overall method compliance.

Methodology and Instrumentation

Standards were prepared from Restek Drinking Water VOA MegaMix and related mixes. Calibration ranged from 0.5 to 50 ppb for most compounds, extended to 125 ppb for ketones and 250 ppb for t-butanol. Seven replicate 0.5 ppb samples determined method detection limits, accuracy, and precision. The Lumin concentrator settings included an 11 min purge at 40 mL/min, 1 min dry purge at 100 mL/min, and a 4 min desorb at 250 °C. GC separation used a Restek Rtx VMS column with helium carrier and a temperature program from 35 °C to 240 °C. MS detection scanned 35–260 m/z on the Clarus SQ8T.

Main Results and Discussion

Calibration curves exhibited %RSDs below 15% for most analytes. MDLs ranged from 0.04 to 3.62 ppb, meeting EPA requirements. Accuracy spanned 92–123% and precision (%RSD) remained within specified limits. Chromatograms at 0.2 ppb and 5 ppb demonstrated clear separation of early eluting compounds and minimal interference from residual water.

Benefits and Practical Applications

The MCS effectively limits water transfer to the GC/MS, reducing column degradation and MS source fouling. Faster trap cooling shortens cycle times, increasing sample throughput in high-volume environmental labs. This method supports regulatory monitoring and quality assurance in drinking water analysis.

Future Trends and Opportunities

Emerging developments may integrate advanced moisture traps, automated moisture monitoring, and coupling with high-resolution MS for non-target screening. Miniaturized, field-deployable purge and trap systems with robotic sample handling could further expand on-site water testing capabilities.

Conclusion

The combination of the Teledyne Tekmar Lumin P&T concentrator, AQUATek 100, and PerkinElmer Clarus 600 GC/Clarus SQ8T MS under EPA Method 524.2 provides robust VOC analysis in drinking water. The system achieves required detection limits, accuracy, and precision with negligible water interference and improved laboratory efficiency.

References

• US EPA. Method 524.2: Measurement of Purgeable Organic Compounds in Water by Capillary Column Gas Chromatography/Mass Spectrometry; Revision 4.1; EPA 600/R-95/131; 1995.