2. Materials and methods
2.1. Sample preparation
Three soil samples (Table 1) were collected from Tidermans
padding area about 10 km upstream of Göta River, Sweden. Mercury
contamination in the soil resulted from waste disposal,
chlor–alkali process and harbor activities (Sweco Viak, 2007). This
soil was also polluted by other trace elements, i.e., zinc, lead and
copper. Three samples were pooled into one composite sample of
approximately 45 kg (wet weight). The composite sample was
oven-dried for 48 h at 45 C, manually disaggregated, homogenized
and subsequently sub-divided by a Riffle splitter prior to the
experiment.