Interlaboratory comparison study of PCBs congeners in coregonid fishes from an Arctic river.

Identification of emerging contaminants in fish species consumed by indigenous peoples remains an important task in the Arctic from the perspective of preserving human chemical safety. This study presents an interlaboratory comparison of the analysis results of polychlorinated biphenyl (PCB) congeners in coregonid fishes, using the Norilo-Pyasinskaya water system on the Taimyr Peninsula as an example, where a large enterprise is located. Two laboratories conducted analyses to quantify PCB levels in the muscle tissue of fish caught at various distances from the suspected contamination source. The Bland-Altman method demonstrated good agreement between the laboratories in the analysis of both the total PCBs and individual congeners 101, 118, 138, and 153. Small differences in results may be due to variations in detector calibration, chromatographic separation, selectivity for specific compounds, or both. Geographical differences in PCB content in coregonid fishes were observed depending on the distance from the suspected pollutant discharge point. Meanwhile, other fish parameters, such as age, weight, and lipid content, had little effect on PCB levels. The use of Standard Reference Materials (SRM) and control materials in laboratories is recommended, as they help confirm analytical results and ensure these procedures remain controlled.