title: Mobilisation of heavy metals by deicing salts in a roadside environment.
abstract: The seasonal variations of some selected heavy metals (Cd, Cu, Pb and Zn) and principal anions in soil solutions were monitored as a function of distance from the road at two field sites in Sweden. During the winter, the conductivity, concentrations of dissolved sodium and chloride increased dramatically due to the application of deicing agents (i.e. NaCl). Due to ion exchange, the pH decreased one unit in the soil solutions, whereas the concentrations of total organic carbon decreased due to coagulation and/or sorption to stationary solids. The heavy metal concentrations increased during the winter, but through different mechanisms. Cadmium concentrations in the aqueous phase increased as a response to ion exchange, possibly also enhanced by the formation of chloride complexes. Similarly, the concentrations of zinc increased, due to ion exchange, with calcium and protons. The mechanisms of mobilisation for copper and lead were not that clear probably due to association with coagulated or sorbed organic matter in combination with colloid dispersion.
authors.affiliation: Man-Technology-Environment Research Centre, Orebro University, SE-701 82 Orebro, Sweden. mattias.backstrom@nat.oru.se
authors.forename: Mattias
authors.initials: M
authors.lastname: Bäckström
authors.forename: Stefan
authors.initials: S
authors.lastname: Karlsson
authors.forename: Lars
authors.initials: L
authors.lastname: Bäckman
authors.forename: Lennart
authors.initials: L
authors.lastname: Folkeson
authors.forename: Bo
authors.initials: B
authors.lastname: Lind
mesh_terms: D003102:Colloids; D004784:Environmental Monitoring; D006863:Hydrogen-Ion Concentration; D007053:Ice; D007474:Ion Exchange; D019216:Metals, Heavy / Q000737:chemistry*; D009930:Organic Chemicals; D012621:Seasons; D012965:Sodium Chloride / Q000737:chemistry*; D013548:Sweden; D014186:Transportation
chemical_list: D003102:Colloids; D007053:Ice; D019216:Metals, Heavy; D009930:Organic Chemicals; D012965:Sodium Chloride