Аннотация:An inter-disciplinary methodology to investigate pollution from maintenance of oil and gas fields and to explore potential impact of new ones has been developed and tested at three oil and gas fields in Western Siberia and Mid-Volga region with different duration of exploitation. The investigations focused on the impact of oil, its derivatives and other chemicals on human health and biocenoses. The research included combination of methods of environmental geology, geophysics, bioindication, cytogenetics and analytical chemistry and is based on the idea that reliable control of concentration, regularities of sorption and the complete tracing of oil pollution in the environment from the source of contamination through the soils, ground and surface water, soil biota and via the food chains to small mammals and birds are needed to assess ecological risk. It is anticipated that direct determination of oil and its derivatives concentration in soil and ground water can provide a basis to understand the results of bioindication. The obtained data revealed the main regularities of the pollutants migration in soils and ground waters, the most dangerous sources of their contamination and demonstrated the impact of gas torches on soils, vegetation and soil-dwelling animals using new reliable and independent indices.