Study of hydrocarbons in bottom sediments of the northern Dvina River-White Sea geochemical barrier during spring flood

The first studies of hydrocarbons in bottom sediments of the mouth of the Northern Dvina River were carried out in May 2005. Measured aliphatic hydrocarbon content of 13 to 1532 μg/g (up to 74% from organic carbon) and polycyclic aromatic hydrocarbons of 3 to 217 ng/g (up to 19.57% × 10 -2 from organic carbon) are compared to their content in regions with permanent input of pollutants and is noticeably higher than the content of hydrocarbons in the studied area in summer. Weathered oil and pyrogenic compounds dominated the composition of hydrocarbons. It has been shown that during flooding, the Northern Dvina - Dvina Bay geochemical barrier becomes a filter, which prevents pollutants from penetrating to the White Sea