Analysis of PCBs and Organochlorinated Pesticides in River Water Using Simultaneous Scan/MRM Measurement in GC-MS/MS (1)

Significance of the Topic

Persistent organic pollutants such as PCBs and organochlorinated pesticides pose long term ecological and health risks as they resist environmental breakdown and accumulate in organisms. Monitoring these compounds in river systems requires high sensitivity to detect trace levels and robust separation from matrix interferences.

Objectives and Study Overview

This study evaluates a simultaneous full scan and MRM measurement approach using a GC-MS/MS system for the analysis of 70 PCB congeners and 22 chlorinated pesticides in water samples. Key aims include assessing detection sensitivity and analytical repeatability under realistic environmental concentrations.

Methodology and Used Instrumentation

Standards included a PCB congener mixture and a chlorinated pesticide mix with isotopically labelled internal standards. Chromatography was performed on a DB-5MS column under splitless injection and a temperature program from 40 to 310 °C. The GCMS-TQ8030 system generated simultaneous scan data over m/z 45 to 600 and high speed MRM transitions. Ultrahigh scan speed of 5000 u/s enabled both targeted and full spectrum acquisition.

• GCMS-TQ8030 triple quadrupole mass spectrometer
• DB-5MS column 30 m × 0.25 mm I D, 0.25 μm film
• Deactivated splitless glass liner without wool

Main Results and Discussion

All target PCBs and pesticides were detected at 1 ng/mL with clear, well resolved MRM peaks. At 5 ng/mL (10 ng/mL for selected pesticides), repeatability studies (n=8) yielded relative standard deviations below 10% for most compounds, though higher molecular weight congeners and certain pesticides exhibited up to 16% RSD. These results demonstrate robust quantitation capabilities.

Benefits and Practical Applications

This simultaneous scan/MRM approach combines the selectivity and sensitivity of targeted MRM quantitation with full scan screening for non target pollutants. It supports rapid environmental monitoring, quality assurance in industrial laboratories, and incident response investigations.

Future Trends and Potential Applications

Advances may include expanded compound libraries, automated data processing with database software, faster acquisition rates, and enhanced sensitivity for ultratrace analysis. Integration with portable instrumentation could enable on site screening.

Conclusion

The described GC-MS/MS method using simultaneous scan/MRM offers a powerful tool for comprehensive analysis of persistent organic pollutants in river water, delivering sensitive and reproducible quantitation along with broad screening capabilities.

References

• Shimadzu Corporation Application Data Sheet LAAN-J-MS-E078 First Edition February 2013