Discrimination between natural background and anthropogenic pollution in environmental geochemistry - exemplified in an area of south-eastern Sweden

In an area of south-eastern Sweden, very high Pb concentrations in biogeoch emical samples (mainly roots of stream plants) were detected. Lead minerali zation in bedrock was found in the same area. Meanwhile, crystal glass indu stries, which emit large amounts of Ph into the environment are located nea rby. It appears necessary to determine whether the high concentrations of P b are derived from natural sources or from anthropogenic pollution. Geograp hical information system (GIS) and multivariate analyses are applied in sol ving the problem. GIS is used for spatial visualization of the problem, and multivariate analyses is used for quantitative discrimination. Concentrati ons of seven heavy metals (Co, Cr, Cu, Ni, Pb, V and Zn) from biogeochemica l samples, till, bedrock samples, and discharge data of pollutants from cry stal glass industries were used. Both visualization by GIS and multivariate analysis provide evidence that the high ph concentrations in the biogeoche mical samples in the studied area mainly come from natural mineralization, not from human pollution. The methodologies developed in this study are app licable in the field of environmental geochemistry. (C) 1999 Elsevier Scien ce B.V. All rights reserved.