GCMSMS as a tool for analysis of POPs in food

Importance of the Topic

Persistent organic pollutants such as dioxins, PCBs and PCNs accumulate in food chains and pose significant risks to human health due to their toxicity and persistence.
Accurate analysis of these contaminants in food and feed is essential for regulatory compliance, consumer safety and environmental monitoring.

Objectives and Study Overview

The primary aim is to evaluate GC-MS/MS as an alternative to high-resolution mass spectrometry (HRMS) for the determination of dioxins, PCBs and PCNs in food matrices.
A validation study was carried out on milk, fish feed, salmon and cod liver oil, reflecting typical food and feed samples relevant to EU regulatory limits.

Methodology and Instrumentation

Sample extraction and cleanup protocols were optimized to remove interferences and concentrate target analytes.
Analyses were performed using a Thermo TSQ Quantum XLS Ultra GC-MS/MS system and a high-resolution mass spectrometer for comparison.
Method validation included instrument installation, a three-week interrupted study and participation in EU-coordinated comparative tests via the European Reference Laboratory network.

Key Results and Discussion

GC-MS/MS demonstrated sensitivity within one order of magnitude of HRMS for dioxin congeners, successfully quantifying PCDD/Fs and ∑ICES6 PCBs at regulatory levels.
At very low concentrations, some ion ratios fell outside tolerance due to limitations in noise estimation, suggesting the method is most reliable as a screening tool or for routine compliance.
For PCNs, HRMS provided robust quantification across all congeners, while MS/MS accurately measured major PCNs but showed higher variability for low-abundance isomers.
Comparative analyses across milk, fish feed and salmon yielded total TEQ values in close agreement between GC-MS/MS and HRMS, confirming the practical applicability of MS/MS.

Practical Applications and Benefits

GC-MS/MS offers a cost-effective, versatile and user-friendly alternative to HRMS for routine monitoring of dioxins, PCBs and selected PCNs in food and feed laboratories.
Its lower capital and operating costs and simplified operation make it well suited for general control laboratories, provided that rigorous cleanup and expertise are maintained.

Future Trends and Potential Applications

There is a growing need to include additional dioxin-like compounds such as PCNs in the TEQ framework and regulatory standards.
Advances in MS/MS sensitivity and noise characterization will enhance detection limits and ion ratio reliability.
Expanded monitoring programs and further repeatability studies on real-world samples will support risk assessment and regulatory decision-making.

Conclusion

GC-MS/MS is a viable and efficient tool for the analysis of POPs in food, capable of meeting EU regulatory requirements for dioxins and PCBs with appropriate method validation.
While HRMS remains the gold standard for confirmatory analysis, GC-MS/MS can serve as a reliable screening and quantification method, especially when resources are limited.
Ongoing method refinement and broader inclusion of emerging contaminants will strengthen food safety and environmental protection efforts.