Statement of Problem: The production, transport, and processing of crude oil are sources of petroleum-related contaminants in surface and ground waters, soils and atmosphere in the Tyumen region of West Siberia. A wide range of oil components such as heavy metals and surfactants enter streams and lakes. The current ecological status of the northern part of the Tyumen region is critically declining. Previous studies have shown that concentrations of petroleum hydrocarbons in surface waters of the region can exceed threshold effect concentrations by more than 10 fold. A steady decrease in catches of valuable fish species such as sterlet, white salmon and whitefish is occurring in the rivers and lakes. Oil components that enter aquatic systems are deposited in the bottom sediments and the most toxic oil components, such as polycyclic aromatic hydrocarbons, resins and asphaltenes accumulate in sediments and are transferred into food webs. The contamination causes changes in the structure of benthic communities, a decrease in fish productivity, deterioration in the quality of fish products, and creates a chronic health hazard for humans that consume water and fish (e.g. exposure to carcinogens and other toxic contaminants). Petroleum-associated contaminants are especially significant for the West Siberia region where oil constitutes 80% of the total contamination and fish plays a significant role in the diet of the human population.
Objectives: 1. Provide chemical, toxicological, microbiological and biological information necessary for more realistic predictions of the environmental behaviour of oil-associated contaminants and for evaluation of the natural attenuation and microbial degradation of petroleum hydrocarbons in aquatic environments in cold climates. 2. Analyze the pattern of oil contaminant distribution and behaviour in rivers and lakes of West Siberia. 3. Study long-term effects of crude oil on the abundance, distribution and activity of the bacterial community in benthic sediment habitats and investigate factors that influence the effectiveness of microbial degradation of petroleum hydrocarbons. 4. Evaluate the impact of oil pollution on communities of benthic organisms and fish. 5. Assess the effects and risks posed by polluted waters and sediments. 6. Provide regional environmental management agencies with data and information on contamination levels, the hazards of long-term pollution of rivers and lakes, the main sources of oil pollution, and the effectiveness of environmental protection actions.