Analysis of Polychlorinated Biphenyls (PCBs) in Fish Oil Supplements by Gas Chromatography with High Performance-Time of Flight Mass Spectrometry

Význam tématu

Fish oil supplements are widely consumed for their omega-3 fatty acids (EPA and DHA), which support cardiovascular health and neurological development. However, these products can accumulate persistent organic pollutants such as polychlorinated biphenyls (PCBs), raising potential health concerns. Accurate, sensitive analysis of trace PCBs in complex fat-rich matrices is therefore critical for ensuring product safety and regulatory compliance.

Cíle a přehled studie / článku

• Evaluate the performance of the LECO Pegasus GC-HRT high-resolution time-of-flight mass spectrometer for PCB analysis in fish oil supplements.
• Demonstrate a sample preparation workflow capable of extracting PCBs from oil matrices with minimal interference.
• Compare chromatographic separation and mass accuracy at high resolution to conventional methods.

Použitá metodika a instrumentace

Sample preparation employed a QuEChERS-style extraction: 1 g of fish oil spiked with a 28-congener PCB standard, mixed with water and acetonitrile, followed by salt addition, vortexing, and centrifugation. A 1.5 mL aliquot of the acetonitrile layer was transferred for analysis.

Instrumentation included:

• Gas Chromatograph: Agilent 7890 with Restek Rtx-PCB column (20 m length, 0.18 mm ID, 0.18 µm df).
• Injection: 1 µL, splitless at 250 °C; oven ramp from 70 °C to 320 °C at 20 °C/min.
• Carrier Gas: Helium at 1.00 mL/min.
• Mass Spectrometer: LECO Pegasus GC-HRT with Folded Flight Path™; EI ion source; positive polarity; high resolution (R = 25 000 at m/z 219); acquisition rate 25 spectra/s; m/z range 50–510; PFTBA calibration.

Hlavní výsledky a diskuse

The Pegasus GC-HRT achieved mass accuracies within ±1 ppm for the majority of PCB congeners. High resolution separation allowed extraction of coeluting species (e.g., PCB 206 vs. glycerol tricaprylate) that would overlap at unit resolution. Extracted ion chromatograms at R = 25 000 virtually eliminated background interferences, enabling detection of PCBs down to 10 ng/g spiking levels.

Přínosy a praktické využití metody

The method offers robust identification and quantification of trace PCBs in oil-rich matrices with minimal matrix effects. High resolving power and sensitivity reduce false positives and improve confidence in low-level pollutant monitoring. This workflow supports quality control in dietary supplements and environmental contaminant screening.

Budoucí trendy a možnosti využití

Future developments may include automation of sample prep, expanded panels for other persistent organic pollutants, and integration with data-processing tools for faster deconvolution. The technology can be extended to petrochemical analysis, metabolomics, and forensic investigations where high mass resolution is advantageous.

Závěr

The LECO Pegasus GC-HRT platform, combined with a QuEChERS extraction, provides a powerful approach for targeted PCB analysis in fish oil supplements. Its high mass accuracy and resolving power enable selective detection of trace congeners in complex lipid matrices.

Reference

1. Kris-Etherton PM, Harris WS, Appel LJ. Circulation. 2002;106:2747–2757.
2. Ahlborg UG et al. Chemosphere. 1994;28(6):1049–1067.