Abstract

 During the last few decades, environmental issues have increasingly become associated with diffuse consumption-related sources. Thus, water environments in urban areas have become hot spots for environmental contamination.
  In Stockholm, Sweden, sediments are contaminated with high levels of metals as well as organic pollutants compared to the guidelines suggested by the Swedish EPA. This presentation will give two examples of how this situation is dealt with in an integrated environmental management by the local environment and health administration. The substances that will be discussed are copper and polycyclic aromatic hydrocarbons (PAH).
  In order to map the sources for copper contamination, a substance flux analysis was made, calculating the flows and stocks of copper in the society as well as the emissions to wastewater treatment plants and to recipients in and around the city. This analysis concluded that four uses of copper, corresponding to 7 % of the total stock, contributed to approximately 90 % of the load. These uses were tap water systems, roofs and facades, aerial lines, and brake linings. As a consequence, local regulations are now being developed to restrict the use of copper in exposed applications.
  In a recent study on the toxicity of extracts from sediments from Stockholm, it was shown that polyaromatic compounds, including PAH, represented a major part of the total toxicity to developing fish embryos. To find the most important sources to PAH in the area, a multivariate statistical method was used, comparing the relative occurrence of different PAH in the sediments to that of known sources. This led to the conclusion that the traffic sector, through vehicle exhausts, tyre wear and asphalt wear, is responsible for at least 50 % of the general PAH contamination in sediments in central Stockholm. As for copper, a local strategy for reducing PAH emissions, is now being developed.