Validation of a Confirmatory GC/MS/MS Method for Dioxins and Dioxin-like PCBS to Meet the Requirements of EU Regulation 709/2014

Significance of the topic

Polychlorinated dibenzo-p-dioxins PCDFs and PCBs are persistent organic pollutants with high toxicity and bioaccumulation potential. Routine confirmatory analysis is essential to ensure feed and food safety under stringent regulatory limits.

Objectives and overview of the study

This study aimed to validate a gas chromatography coupled with triple quadrupole mass spectrometry GC/MS/MS method for confirmatory monitoring of PCDDs PCDFs and dioxin-like and non-dioxin-like PCBs in animal feed according to EU Regulation 709/2014. The goal was to demonstrate performance equivalent to GC/HRMS while reducing cost and complexity.

Methodology and Instrumentation

The method utilized an Agilent 7890B GC system linked to an Agilent 7000C triple quadrupole MS/MS. Key elements included

• 13C-labeled internal standards and recovery standards for PCDD/Fs NO-PCBs and MO-PCBs
• Retention time locking on PCB-105
• Multiple reaction monitoring with two transitions per analyte for quantitation and confirmation
• Calibration at low picogram per microliter levels

Vegetable oil samples underwent established cleanup protocols, followed by solvent vent injection and a tailored oven temperature program to resolve all target congeners.

Main results and discussion

The GC/MS/MS approach achieved instrumental limits of quantitation comparable to GC/HRMS for PCDD/Fs and dioxin-like PCBs. Instrumental LOQs were defined statistically and method LOQs incorporated background variation from procedural blanks. Calibration curves showed strong linearity with R2 values above regulatory thresholds. Method bias and precision at levels around the maximum limits met EU requirements of bias below 20% and RSD below 15%. Blank control charts over six months confirmed long-term robustness. Background subtraction based on averaged blank levels ensured reliable low-level quantitation.

Benefits and practical applications

• Cost effective alternative to high resolution MS for official confirmatory testing
• Full compliance with EU Regulation 709/2014 for dioxin and PCB monitoring
• High selectivity and flat baselines from MRM enhance peak identification
• Reduced maintenance demands compared to HRMS systems

Future trends and opportunities

Expanding the use of triple quadrupole MS/MS for persistent pollutant analysis in diverse matrices can further lower detection limits. Advances in ion optics and data processing may enable complete replacement of HRMS in routine control labs. Integration with automation and high-throughput sample handling will strengthen regulatory compliance and rapid screening workflows.

Conclusion

The validated GC/MS/MS method fulfills all confirmatory criteria in EU Regulation 709/2014, delivering sensitive accurate and reliable measurements of dioxins and PCBs in animal feed. It represents a viable economical alternative to GC/HRMS for official control applications.

Reference

1. L Homme B Scholl G Eppe J Focant Validation of a gas chromatography triple quadrupole mass spectrometry method for confirmatory analysis of dioxins and dioxin like polychlorobiphenyls in feed following EU Regulation 709/2014 Journal of Chromatography A 1376 149–158 2015
2. Focant J F Eppe G Pirard C Massart A C Andre J E De Pauw Levels and congener distributions of PCDDs PCDFs and non-ortho PCBs in Belgian foodstuffs assessment of dietary intake Chemosphere 48 167–179 2002
3. Kotz A Malisch R Wahl K et al GC/MS/MS determination of PCDDs PCDFs and PCBs in feed and food comparison with GC/HRMS Organohalogen Compounds 73 688–691 2011
4. Commission Regulation EC No 277/2012 amending Annexes I and II to Directive 2002/32/EC Off Journal of European Community L91 2012
5. Commission Regulation EU No 709/2014 amending Regulation EC No 152/2009 Off Journal of European Community L188 2014
6. Kotz A Malisch R Focant J F et al Analytical criteria for use of MS/MS for determination of dioxins and dioxin like PCBs in feed and food Organohalogen Compounds 74 156–159 2012