Polyaromatic hydrocarbons in sediments from the Barents and White Seas

Polycyclic aromatic hydrocarbons (PAHs) are common environmental contaminants which can be derived from anthropogenic sources, such as combustion and discharges from extraction and transport, and natural processes, including leakage and erosion of fossil carbon. Natural PAH sources contribute, along with biological activities and terrestrial run-off, to the organic carbon content in sediments.The Barents Sea region is far from many anthropogenic sources of PAH, but production and trans-shipment of hydrocarbons is increasing. We present data for polycyclic aromatic hydrocarbon (PAH) concentrations in bottom sediments from 510 stations in the Barents and White Seas, and along the northern coast of Norway.

Contents of hydrocarbons in waters and bottom sediments of the southwestern Amur Bay (Sea of Japan) in April 2005

Abundances and compositions of aliphatic hydrocarbons (AHC) and polyaromatic hydrocarbons (PAH) were investigated in water and bottom sediments of the southwestern Amur Bay, Sea of Japan. Water contained 0-129 ?g/l AHC (average 42.2 ?g/l) and 5-85 ng/l PAH (average 18 ng/l). Bottom sediments contained 168-2098 ?g/g AHC and 7.2-1100 ng/g dry mass PAH. It was shown that input of anthropogenic hydrocarbons is better recorded by molecular markers than by distribution of AHC and PAH concentrations. Discovery of elevated hydrocarbon concentrations in the bottom water layer suggests that bottom sediments induced secondary contamination of the water body.

Hydrocarbons in particulate matter and bottom sediments from the north Caspian Sea shelf

Data are presented on content and composition of hydrocarbons (HC) (aliphatic AHC and polyaromatic PAH) in filtered particulate matter and in the surface layer of bottom sediments from the northern shelf of the Caspian Sea and related to data on their contents in the Volga River estuary. Because of transformation and precipitation of anthropogenic and natural compounds, HC composition in particulate matter and bottom sediments undergoes transformations caused by mixing of fresh and saline waters (in bottom sediments, within concentration ranges 70.4-4557.9 µg/g for AHC and 3.8-4800 ng/g for PAH). It was found that the greatest concentrating of HC proceeds in the region of the avalanche sedimentation, and their contents are independent of grain-size types of bottom sediments. Anthropogenic HC (oil and pyrogenous) do not get over the marginal filter of the Volga River and do not pass to the open part of the sea.