Analyzing Multi-Class Persistent Organic Pollutants (OCPs, PCBs, PBDEs, and PAHs) in Food Matrices in a Single Injection by APGC-MS/MS

Overview of Multi-Class Persistent Organic Pollutants Analysis by APGC-MS/MS

Importance of the Topic

Persistent organic pollutants (POPs) such as OCPs, PCBs, PBDEs and PAHs pose significant risks due to their persistence, lipophilicity and toxicity. They accumulate in food chains and are regulated globally, necessitating routine monitoring at trace levels in complex food matrices.

Study Objectives and Overview

The study aimed to develop and validate a single-injection analytical method combining atmospheric pressure gas chromatography with tandem mass spectrometry (APGC-MS/MS) to quantify 141 POPs across four classes in various foodstuffs (milk, infant formula, beef, pork, chicken, fish). A generic sample preparation workflow was employed to streamline multi-class analysis.

Methodology and Instrumentation

• Sample Preparation: Homogenized samples (10–12 g) were spiked with isotopically labelled internal standards, extracted with ethyl acetate and QuEChERS salts, followed by gel permeation chromatography (EnvirosepABC, dichloromethane) and silica cleanup.
• Gas Chromatography: Agilent 7890A with a DB-5 column (30 m×0.25 mm×0.25 µm), splitless 1 µL injection, temperature gradient from 70 °C to 310 °C, helium carrier gas.
• Ionization and MS/MS: Atmospheric pressure gas chromatography (APGC) source with APCI corona discharge (2.5 µA) enabling charge and proton transfer ionization. Waters Xevo TQ-S triple quadrupole using multiple reaction monitoring (MRM) in positive mode. Data acquired and processed with MassLynx and TargetLynx.
• Validation: LOD/LOQ calculated as 3× and 10× standard deviations of noise (IUPAC). Recoveries, repeatability (%RSD), linearity (R²>0.99) assessed across six matrices at fortification levels 0.2×, 1× and 2× the lowest limit.

Main Results and Discussion

Across pork and other matrices, recoveries ranged from 65% to 122% with repeatability ≤20% RSD. Limits of detection were below 1 µg·kg⁻¹ for all analytes. APGC greatly improved molecular ion abundance compared to EI; for example, signal-to-noise for BDE 17 increased from 120 to over 600 at 2 pg on-column. Calibration over 2–25 µg·kg⁻¹ was linear (R²>0.99) for representative compounds in each class.

Benefits and Practical Applications

• Multi-class quantification in a single injection reduces analysis time and resource consumption.
• Generic extraction and cleanup ensures robust recovery across diverse food matrices.
• Enhanced sensitivity and selectivity improve trace-level detection and reduce maintenance compared to EI methods.
• Method accredited to ISO 17025 and implemented for routine food safety monitoring by MAPAQ.

Future Trends and Potential Applications

Expanding APGC-MS/MS to additional emerging contaminants, integrating high-resolution MS for non-target screening, automating sample preparation and data processing, and adapting portable GC-MS platforms for field applications can further enhance monitoring capabilities.

Conclusion

The validated APGC-MS/MS method on the Waters Xevo TQ-S delivers reliable, high-throughput analysis of 141 POPs in food matrices. The approach offers improved sensitivity, streamlined workflow and compliance with regulatory requirements, supporting comprehensive food safety surveillance.

Reference

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