Heavy metal pollution of natural origin in the Rio Norizzi basin (Southwestern Sardinia, Italy). The As aspect

摘要

During a campaign of geochemical investigations concerning the artificial lakes in Sardinia (Italy), high heavy-metal contents were detected in the stream sediments of the basin of Rio Norizzi, a small tributary of Lake Mulargia. In particular, As was prominent for its "anomalous" values. A statistical study on the distribution of this element on 86 stream sediment samples has been performed, and the results compared with risk parameters. The pollution observed, which looks to derive only from natural sources, is serious, with problems concerning both the soils of the studied basin and the water of Lake Mulargia. Further studies are recommended in order to better assess the real risks.