The contamination of Dutch soils with mercury and a few other heavy metals

Abstract

As a result of his history the average dutchman knows the various soil types in his country quite well, the chemical structure is usually unknown. The paper describes the typical aspects of the soil constituents as there arc clay minerals, sands and organic materials, Specially the properties, which control the adsorption of traces of heavy metals and pesticides got attention. An important part of the paper is devoted to the behaviour of mercury in dutch and other western european soils. Because part of the drinking water companies in the western part of Holland produce their drinking water from the River Rhine by filtration through dunes, the migration of mercury in soils got serious attention. Most mercury compounds (Hg, HgCl2, HgCICH3) do not migrate in soil, the volatile Hg (CH3)2 migtates fast. The contamination of soils is partly caused by agricultural measures' partly by flooding with water from the Rhine. An analysis of the available data indicated, however, that the main mercury source stems from the wash out of the atmosphere. The contamination of soils in areas with a high population density and much industry is considerably higher than in other areas. A similation model was developed to describe the mercury fall out drain rate.