Soil extraction methods for the assessment of the ecotoxicological risk of soils

A combination of chemical and biological analytical methods has been proofed as suitable for an estimation of a possible groundwater contamination by contaminated and remediated soils. A broad set of methods is proposed for the preparation of soil eluates. A comparison of the concentrations of contaminants in soil eluates shows that a soil/water ratio of 1/2 is most practicable. In these eluates the concentration of the pollutants in all samples range slightly above the concentration in soil saturation extracts. For preparing soil eluates for analytical determinations or ecotoxicity tests appropriate clean up steps are very important. A combination of centrifugation and filtration by glass fibre microfilters or a combination of two filter types is recommended.