Abstract
The results of determining the content and composition of aliphatic hydrocarbons (HCs) in suspended matter on the geochemical barrier of the river (Ob, Yenisei, Lena, Khatanga, Indigirka, Kolyma) - the sea (Kara, Laptev, and East Siberian), obtained in 2015-2017, were presented. It was shown that the distribution of HC concentrations in general with the content of the suspended matter. Losses in HC concentrations in the zone of mixing of river and sea waters in some cases exceeded 90% of their removal by the river. In the pelagial of the seas, the HCs were closed to the background (2-7 µg/l). The behavior and composition of HCs depends on the characteristics of the catchment area of the rivers, the sampling season and the time of day (tide, outflow). The influence of anthropogenic inflows was established only in the Ob Bay, where the composition of alkanes is close to oil and the HCs was 86 µg/mg of the suspension. The remaining samples are dominated by natural hydrocarbons.