RT Journal Article
T1 Geochemical characterisation of surface waters, topsoilsand efflorescences in a historic metal-mining area in Spain
A1 Pérez Sirvent, Carmen
A1 Hernández Pérez, Carmen
A1 Martínez Sánchez, Maria José
A1 García Lorenzo, María de la Luz
A1 Bech, Jaume
AB PurposeMining activities generate large amounts of wastes that may contain potentially toxic elements (PTE), which, if released into the environment, may cause air, water and soil pollution long after mining operations have ceased. This paper describes the environmental relevance of efflorescences, topsoils and surface waters from the abandoned mine of Sierra Minera of Cartagena-La Unión, SE Spain. The exposure of the population to arsenic and the associated risk were also assessed.Materials and methodsA total of 10 topsoils and surface waters and 11 efflorescences affected at varying degrees by mining activities were studied. The total potentially toxic element content (As, Cd, Cu, Fe, Pb and Zn) was determined in all samples. In addition, the mineralogical composition of solid samples was determined by X-ray diffraction and some efflorescences were also analysed using a scanning electron microscopy-energy dispersive X-ray spectrometer. Finally, an arsenic-intake risk assessment was carried out, both as regards carcinogenic and non-carcinogenic effects and considering the total and the bioaccesible As content.Results and discussionThe study area is heavily polluted as a result of historical mining and processing activities, during which time great amounts of wastes were produced, characterised by a high PTE content, acidic pH and minerals resulting from supergene alteration. The supergene mineralogical assemblages include soluble metal salts, mainly sulphates, iron hydroxysulphates and iron oxyhydroxides, all of which form ochreous precipitates. Topsoil samples showed risk values and hazard quotients higher than the reference levels, particularly for children. In the efflorescences, these values were lower but still unacceptable.ConclusionsThe efflorescences are of significance for monitoring purposes because they are involved in cycles of retention release of hydrogen ions, sulphate and potentially toxic elements. In addition, in a semi-arid climate, such as the study area, these minerals contribute to our understanding of the response of the system to episodic rainfall events. In general, it was observed that the arsenic in collected samples represent a potential risk for human health through ingestion.
PB Springer
SN Issn: 1439-0108  (Print) ; 1614-7480 (Online)
YR 2016
FD 2016-04
LK https://hdl.handle.net/20.500.14352/23703
UL https://hdl.handle.net/20.500.14352/23703
LA eng
DS Docta Complutense
RD 6 abr 2025