Distribution of polycyclic aromatic hydrocarbons in surface sediments of lower reaches of the Don River (Russia) and their ecotoxicologic assessment by bacterial lux-biosensors

Abstract

The lower Don River in the south of the European part of Russia was studied to determine the concentration, spatial distribution, and sources of 19 polycyclic aromatic hydrocarbons (PAHs) in surface sediments. Total PAH concentrations ranged from 14.2 to 529 ng/g-dw. Sedimentary PAH concentrations were higher in the delta of the Don River and in the estuaries of rivers Sal and Aksai compared to the main channel of the Don. Analysis of the PAHs sources showed that PAHs came mostly from pyrogenic sources as a result of incomplete combustion of coal. Bioluminescent bacterial sensors were used for ecotoxicological assessment of surface sediments. The surface sediments of all the investigated stations of lower reaches of the Don River were toxic and genotoxic. The maximum concentration of PAHs and the high genotoxicity effect caused by the presence of genotoxicants were found in the surface sediments of the same stations. Significant correlations between the concentrations of individual PAHs in sediments and the genotoxic effect were found. Correlation between genotoxicity of surface sediments and concentration of phenanthrene and benz(k)fluoranthene was the most significant both with and without application of metabolic activation.

Biosensor-Based Assessment of Pesticides and Mineral Fertilizers’ Influence on Ecotoxicological Parameters of Soils under Soya, Sunflower and Wheat

“…The bioavailability of pollutants, not just their direct concentration in environmental samples, is also important. This was shown by Sazykin et al [32] when studying the ecotoxicity of river Don bottom sediments using bacterial lux biosensors, as well as by Azhogina et al [18], who found a close connection between the response of biosensors and the concentration of bioavailable PAHs.…”

Evaluation of So-Iuy Mullet Tissues Toxicity Using Whole-Cell Bacterial Luminescent Sensors

“…Кроме того, самые распространенные химические вещества не обязательно оказывают наибольшее биологическое воздействие на водные организмы. Важные данные для оценки экологических рисков, возникающих в водных экосистемах, можно получить с помощью биотестирования на основе цельноклеточных люминесцентных бактериальных сенсоров, которое дополняет химические анализы [4,5] Для приготовления экстрактов в колбу Эрленмейера вместимостью 50 мл вносили по 10 г исследуемых тканей рыб и 10 мл 1%-ного раствора TWEEN-80 (Amresco) в 96%-ном этаноле. Получившуюся суспензию помещали в шейкер-инкубатор Innova 40R (New Brunswick Scientifi c, США) и экстрагировали в течение 24 часов при температуре 30 °С и скорости вращения 250 оборотов в минуту.…”