title: Toxicity and potential risk assessment of a river polluted by acid mine drainage in the Iberian Pyrite Belt (SW Spain).
abstract: Metal contamination from acid mine drainage (AMD) is a serious problem in the southwest of the Iberian Peninsula, where the Iberian Pyrite Belt is located. This zone contains original sulfide reserves of about 1700Mt distributed among more than 50 massive sulfide deposits. Weathering of these minerals releases to the waters significant quantities of toxic elements, which severely affect the sediments and surface waters of the region. The main goal of this paper is to evaluate the toxicity and the potential risk associated with the mining areas using Microtox test and different factors which assess the degree of contamination of the sediments and waters. For this, a natural stream polluted by AMD-discharge from an abandoned mine has been studied. The results show that elevated concentrations of Cu, As and Zn involve an important potential risk on the aquatic environment, associated both with sediments and waters. Microtox test informs that the sediments are extremely or very toxic, mainly related to concentrations of Fe, As, Cr, Al, Cd, Cu and Zn. Pollution is mainly transferred to the sediments increasing their potential toxicity. A natural creek affected by AMD can store a huge amount of pollution in its sediments while exhibiting a not very low water pH and low water metal concentration.
authors: Cátedra UNESCO/UNITWIN/WiCop, Departamento de Química Física, Facultad de Ciencias del Mar y Ambientales, Universidad de Cádiz, CP 11510 Puerto Real, Cádiz, Spain. aguasanta.miguel@uca.es
authors: Aguasanta M
authors: AM
authors: Sarmiento
authors: Angel
authors: A
authors: DelValls
authors: José
authors: J
authors: Miguel Nieto
authors: María José
authors: MJ
authors: Salamanca
authors: Manuel A
authors: MA
authors: Caraballo
mesh_terms: D019015:Geologic Sediments / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D007220:Industrial Waste / Q000009:adverse effects* / Q000032:analysis; D019216:Metals, Heavy / Q000032:analysis / Q000633:toxicity*; D008906:Mining; D018570:Risk Assessment; D045483:Rivers / Q000737:chemistry*; D013030:Spain; D018675:Toxicity Tests; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D007220:Industrial Waste; D019216:Metals, Heavy; D014874:Water Pollutants, Chemical