Contents and behaviour of Mercury as compared with othe heavy metals in sediments from the rivers Rhine and Ems

Abstract

Mercury is one of the various waste substances transported by the river Rhine across the German-Dutch border. Together with a number of other heavy metals mercury is present in large quantities. Upstream these metals are predominantly fixed to the suspended solids in the water and may be deposited on river flats and flood plains. From the fresh-water tidal area of the river onward, however, these elements are more or less solubilized during their transport as organo-metallic complexes. The mobilization of mercury is most pronounced in this respect. Leading to more normal amounts of this element in sediments from the Wadden Sea. This article deals with the behaviour of mercury through the whole Rhine estuary as compared with a number of other heavy metals. As a counterpart of the Rhine the same processes ale described for the river Ems. The latter may be regarded as a classic example of an unpolluted stream.