Polycyclic aromatic hydrocarbons in the snowpack of Yamal-Nenetz Autonomous region as indicators of anthropogenic source influence

Abstract

A study of the content and composition of polycyclic aromatic hydrocarbons (PAHs) in the solid fraction of the snowpack is carried out on the territory of the Yamal-Nenetz Autonomous region, the north of Western Siberia. The total content of ten three-six nucleus PAHs was determined in the 51 samples collected at various distances from oil and gas producers and roads, near settlements, and in remote Arctic areas. The total PAH content varies from the lowest 0.3 ng/mg on the Bely Island, increasing to ~ 5 ng/mg in areas of new gas fields, and up to high 15 ng/mg in cities. Characteristic features of PAHs composition under the influence of gas flares emissions in central areas of high technogenic load are identified; they are a total content of up to 144 ng/mg and enrichment with low- molecular weight PAHs. In remote Arctic regions, high-molecular weight 5–6 nucleus PAHs dominate. Profiles of individual PAHs near gas flares, roads and residential sector facilities have been determined. The percentage contribution of the sum of 3, 4 and 5, 6-nucleus PAHs to the total PAH content indicates the gas flaring impact. Ratios of fluorantene to pyrene and benzene(b)fluorantene to benzene(ghi)perylene indicate changes in the snow PAHs composition with a decrease in the gas flaring contribution. The data obtained for the assessment of gas flaring emission impact on the PAHs composition in the snowpack are relevant to polar areas where new fields are being developed.