Temporal Trends and Spatial Distribution of PCBs in the Pelagic Sculpin Comephorus Baicalensis from Lake Baikal (2000–2023)

Levels of PCBs were determined in Comephorus baicalensis (Pallas, 1776), a pelagic sculpin endemic to Lake Baikal. Concentrations of PCBs were measured using GC/MS. The maximum concentrations over the entire study period (2000–2023) were found for ƩPCB(31) (694–1669 ng/g lw). The decreasing trend of ƩPCB(31) concentrations was revealed using the Mann–Kendall test. With regard to the percentage composition of the PCBs, increasing trends were found for PCB 99, PCB 85, PCB 118 and negative trends for PCB 28, PCB 149, PCB 132, PCB 126, PCB 177, PCB 170. The results indicate that the southern basin of Lake Baikal continues to experience considerable pressure from the ongoing influx of PCBs.