In some sediment cores from Lake Greifen, the adsorbed
EDTA was determined (Figure 5). The measured EDTA concentrations
in the sediment are in the range 2 10-10-4 10-9
mol/g. If the sediment has a water content of 80% with a
concentration of EDTA of 2 10-8 M in the pore water (the same
concentration as in the overlaying water), this leads to a concentration
of 8 10-11 mol/g EDTA in the solid phase. The EDTA
concentration from the pore water is, therefore, at least 1 order
of magnitude lower and does not affect the determination of the
adsorbed EDTA. The highest concentrations were found in the