Author:

Keywords:

trace elements, background values

Abstract:

Vanadium (V) is a naturally occurring trace element, but total concentrations in soils and sediments are also dependent on the parent material and might be influenced by anthropogenic activities (e.g. steel industry). Despite the fact that threshold values for V in soils and/or sediments exist in various European countries, in Flanders (Belgium), V is not taken into account when the environmental quality of soils and sediments has to be evaluated, despite the existence of several (diffuse) sources for V in Flanders. In a first part of the study, the occurrence of V in soils and sediments in Flanders was compared with V-concentrations in soils and sediments across Europe. The study was based on an analysis of data from 250 soils and sediments in Flanders (own work) and data from a European database (FOREGS database). Secondly, the mobility of V in soils and sediments under varying environmental conditions of pH and Eh was assessed based on porewater analysis, resuspension tests, pHstat leaching tests and column experiments. By analysis of both the Flemish and European data, the relationship between physico-chemical soil and sediment characteristics and total V-concentrations was quantified and some locations polluted with V were detected. A background value, corrected for the clay and organic matter content of soils and sediments, was proposed for Flanders. Leaching tests and porewater analysis indicated that V generally displayed a low mobility in soils and sediments, although in a few particular cases attention should be paid to the potential mobilization of V.