Urban geochemistry in Trondheim, Norway

Abstract

The chemical composition of urban surface soil in Trondheim, Norway, has been mapped to serve a two-fold purpose.\r1.) To assess whether stack-emissions from industrial sites, incinerators and crematoria as well as road traffic, have caused local elevated concentrations of certain elements.\r2.) To provide a database for environmental health risk evaluation. \rSurface soil samples were collected from 314 sites in gardens, parks and industrial areas. The samples were analysed for tha Aqua Regia soluble fraction of 31 elements. Natural background concentration were determined in the deeper parts of overbank sediment profiles from the region. In general, the pollution levels were low. However, Cd, Hg, Pb and Zn pollute the surface soils in the central and older parts of the city and along the main roads. The most dominant sources are presumably automobile exhaust (Pb), tyre wear (Zn and Cd), and emissions from a crematorium or a hospital incinerator (Hg). In the eastern parts of Trondheim, industries burning coal have probably caused elevated As concentrations.