Content and Composition of Hydrocarbons in Water and Sediments in the Coastal Regions of the Russian Sector of the Black Sea

The current level and origin of hydrocarbons (HCs): aliphatic (AHCs) and polycyclic aromatic (PAHs) were determined (September 2021 and May and September 2022) in suspended particulate matters (SPM) of surface waters (for AHCs, 20 µg/l; for PAHs, 130 ng/l, fluorescent method) and in bottom sediments of the coastal areas of the Caucasian sector of the Black Sea of the Russian Federation. Despite a decrease in the HC concentrations in the surface waters in recent years, the most polluted areas include, as before, Kerch Strait. HC accumulate in the bottom sediments, which leads to an increase in their content in the composition of C org (for AHCs, up to 14.2% in the Tuapse region and 13.1% in the Novorossiisk region). It has been established that, along with pollution, the HC levels are greatly influenced by natural processes (the productivity of the area and fluid flows from the sedimentary formation).