Low-level consistent analysis of PBDEs in environmental and food matrices using triple quadrupole GC-MS/MS

Significance of the Topic

Polybrominated diphenyl ethers (PBDEs) are persistent organic pollutants once widely used as flame retardants in plastics, electronics, textiles and other consumer products. Their environmental persistence, potential for bioaccumulation and link to cancer and endocrine disruption make sensitive and reliable analysis essential for environmental monitoring, food safety and regulatory compliance.

Objectives and Study Overview

This study aimed to evaluate the performance of the Thermo Scientific TSQ 9610 triple quadrupole GC-MS/MS system, coupled to a TRACE 1610 gas chromatograph, for the determination of 24 PBDE congeners in water, soil and fish oil matrices. Key goals included demonstration of chromatographic separation of isobaric congeners, assessment of sensitivity (instrument detection limits, IDLs, and limits of quantitation, LOQs), linearity, reproducibility and robustness over extended sample sequences.

Methodology

Samples (aqueous, solid and fish oil) were extracted via separatory funnel or accelerated solvent extraction or Soxhlet, cleaned with acid/base silica and alumina columns, and concentrated to 20–200 µL in nonane. Calibration employed five-level native and ^13C-labeled PBDE standards (0.25–2000 ng/mL) with isotope dilution. Instrumental analysis used timed-selected reaction monitoring (t-SRM) on the TSQ 9610 with an XLXR electron multiplier detector.

Instrumentation Used

• Thermo Scientific TSQ 9610 triple quadrupole mass spectrometer with NeverVent Advanced Electron Ionization (AEI) source
• Thermo Scientific TRACE 1610 gas chromatograph with iConnect PTV injector (splitless mode) and AI/AS 1610 autosampler
• TraceGOLD TG-PBDE capillary column (15 m × 0.25 mm × 0.10 µm) with thin film phase resistant to 360 °C
• Chromeleon CDS software v7.3 for data acquisition, processing and isotope-dilution quantitation

Key Results and Discussion

Chromatographic separation of all PBDE congeners was achieved in under 13 minutes. Critical isobaric pairs (PBDE-49/71) exceeded EPA Method 1614 resolution criteria (valley height resolution of 5%). PBDE-209 exhibited Gaussian peak shape (asymmetry 1.1) despite high boiling point. Calibration was linear from 0.25 to 2000 ng/mL (R² > 0.99, AvCF %RSD < 15%). IDLs ranged from 5 to 122 fg on column (0.25 pg/L to 6.10 pg/L in water; 0.025 to 0.61 ng/kg in soil/fish oil); LOQs from 0.03 to 1.25 ng/mL. Robustness testing (n = 100 matrix injections) showed ion ratios within ±30% of expected, QC peak area %RSD < 20% and stable response without any source or inlet maintenance.

Benefits and Practical Applications

• High-throughput analysis (<13 min) with confident separation of isobaric PBDE congeners
• Ultra-trace sensitivity suitable for regulatory monitoring in environmental and food safety laboratories
• Reduced downtime via NeverVent AEI source and plug-and-play GC modules
• Fully automated isotope dilution workflow in Chromeleon CDS ensures accurate quantitation and compliance with 21 CFR Part 11

Future Trends and Opportunities

Advances in ion source design and detector technology will further enhance sensitivity and dynamic range. Expanded compound libraries and automated sample preparation can streamline analysis of emerging persistent organic pollutants. Integration with machine-learning-based data processing may improve identification confidence and trend analysis in complex environmental matrices.

Conclusion

The TSQ 9610 GC-MS/MS system, combined with the TRACE 1610 GC and AI/AS 1610 autosampler, delivers robust, selective and sensitive analysis of PBDEs in challenging environmental and food matrices. The platform supports high throughput, minimal maintenance and regulatory compliance for routine monitoring and research applications.

References

1. US EPA. Technical Fact Sheet – Polybrominated Diphenyl Ethers (PBDEs). November 2017.
2. UN Environment Programme. Guidance for the Inventory of PBDEs Listed under the Stockholm Convention.
3. US EPA Method 1614A. Brominated Diphenyl Ethers in Water, Soil, Sediment, and Tissue by HRGC/HRMS. May 2010.