The rapid development in the Athabasca Oil Sands Region (AOSR) in northeastern Alberta, Canada, has raised concerns about the impact of the industrial emissions on the surrounding terrestrial and aquatic ecosystems. Stable isotope techniques may help to trace the transport and fate of industrial emissions provided that they are isotopically distinct from background isotope ratios in environmental receptors. In order to trace nitrogen (N) and sulfur (S) emissions released by the oil sands industry, chemical and isotopic compositions of various N and S compounds in emissions, in atmospheric deposition, and in several environmental receptors were determined. It was found that d18O values of nitrate and sulfate and ?17O values of nitrate are indicators that constitute excellent new monitoring tools for tracing industrial N and S emissions in the surrounding environment. Application of quantitative and qualitative stable isotope tracers revealed that industrial N and S emissions were observable in the surrounding environment within ca. 30 km distance to the major emission source