Antimony contamination of surface water at abandoned Sardinian mine sites

CIDU, ROSA;Biddau R;DORE, ELISABETTA

2012-01-01

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Abstract

The element antimony raises much concern from both toxicological and environmental viewpoints. The World Health Organization has established a guideline value of 20 μg/L Sb for drinking water, while the Italian legislation indicates a lower value (5 μg/L Sb). Antimony is ubiquitously present throughout the environment as a result of both natural and human processes. Particularly high concentrations of Sb may occur in water draining abandoned mining sites and in adjacent soils. This study is aimed to assess the Sb occurrence, and dispersion in aquatic systems located in the Sarrabus-Gerrei mining district, south-eastern Sardinia (Italy). In this area, Sb ores have been mined till the 1980s. Thereafter, mines were closed and mining residues were abandoned without intervention to mitigate the environmental impact. Surface waters downstream of the mine show high concentrations of Sb (up to 1500 μg/L) and As (up to 230 μg/L). Contamination extends several kilometers downstream of the mine and affects the Flumendosa river, which water is used for irrigation and domestic purposes. Antimony concentrations in the Flumendosa water exceed 5 times the Italian standard for drinking water. The Regional Government has recently recognized this site as a priority in the remediation plan for contaminated sites. The results derived from this study can give a valuable contribution in the correct management and preservation of aquatic bodies, and also in suggesting the appropriate actions able to mitigate environmental effects in Sb-contaminated aquatic systems.