Chlorophenol compounds in freshwater lakes of subarctic regions

Abstract

Chlorophenol compounds, representing a group of chlorinated phenols and their derivatives, are ionic compounds with different degree of hydrophobicity, lipophilicity and acidity. As potential anthropogenic sources of pollution of ecosystems by chlorophenol compounds is the regional atmospheric transport of these compounds from the territories of border regions. At the same time, the sources of the diversity of chlorophenol compounds are the natural processes of enzymatic biosynthesis in the components of the environment. These compounds are especially dangerous for the Arctic and subarctic ecosystems, since the conditions of the cold climate contribute to their longterm preservation, which increases their negative impact on living organisms.

The research area includes subarctic small thermokarst lakes located in the central part of Vaigach Island and in Bolshezemelskaya tundra.

The isolation of chlorophenol compounds from bottom sediment samples was carried out by accelerated liquid flow-through extraction with a hot mixture of organic solvents with extraction of easily and hardly extractable chlorophenol compounds and subsequent analysis on a gas chromatograph with an electron-capture detector. The total content of chlorophenol compounds was determined by summing their concentrations in the easily and hardly extractable fractions.

The bottom sediments of the investigated lakes were characterized by a relatively high content of chlorophenol compounds. Toxic pentachlorophenol was found only in the sediments of lake Tundra Bolshezemelskaya. The revealed presence of chlorophenol compounds in the bottom sediments of the investigated lakes suggests their spread in the environment by atmospheric transport from abiogenic sources, as well as natural enzymatic and biochemical processes in these Arctic waters.