Mobilisation of heavy metals by deicing salts in a roadside environment

• 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.

Ämnesord

NATURVETENSKAP  -- Geovetenskap och miljövetenskap -- Oceanografi, hydrologi och vattenresurser (hsv//swe)

NATURAL SCIENCES  -- Earth and Related Environmental Sciences -- Oceanography, Hydrology and Water Resources (hsv//eng)

Nyckelord

deicing

soil solution

ion exchange

chloride complexes

organic-matter

soil solution

contaminated soils

groundwater

contamination

capillary electrophoresis

lead activity

stream water

fulvic-acid

sandy soil

cadmium

NATURAL SCIENCES

Enviromental Science

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)