title: Sources of mercury in groundwater and soils of west Gijón (Asturias, NW Spain).
abstract: This work aimed to determine the cause of the presence of high concentrations of mercury in several springs that exhibit a low concentration of metals in the bedrocks of their recharge areas in Gijón, NW Spain and the extent of this contamination. On the basis of geological mapping, different lithological substrata were analysed at the regional scale with the objective of establishing the base level of mercury in natural soils. The mercury content was simultaneously analysed in several water samples, and the following parameters were also determined: major anions and cations, As, Pb, δ(34)S, and δ(18)OSO4. The soils of the recharge area of the springs exhibited Hg concentrations that were higher than the base level established for sandstone at the regional level, and four of the total number of springs analysed exhibited Hg concentrations higher than 1 μg/l. In addition, the sulphate concentration exceeded the values that this type of aquifer shows in other parts of the region. A comparison between the regionally geochemical background of soils and mercury concentration in springs and soils of the study area did not exhibit a direct relationship, suggesting an anthropogenic and timely origin (most likely from industrial emissions) for this metal. The δ(34)S and δ(18)OSO4 values of dissolved sulphate from the springs with a higher Hg concentration also indicate an anthropogenic origin.
authors.affiliation: Dpto. de Explotación y Prospección de Minas, Universidad de Oviedo, C/Independencia, 13, 33004 Oviedo, Asturias, Spain. Electronic address: mbeagf@uniovi.es.
authors.forename: B
authors.initials: B
authors.lastname: González-Fernández
authors.affiliation: Dpto. de Explotación y Prospección de Minas, Universidad de Oviedo, C/Independencia, 13, 33004 Oviedo, Asturias, Spain. Electronic address: ecasares@uniovi.es.
authors.forename: E
authors.initials: E
authors.lastname: Menéndez-Casares
authors.affiliation: Instituto Geológico y Minero de España, C/Matemático Pedrayes, 25, 33005 Oviedo, Asturias, Spain. Electronic address: m.melendez@igme.es.
authors.forename: Mónica
authors.initials: M
authors.lastname: Meléndez-Asensio
authors.affiliation: Dpto. de Geología, Universidad de Oviedo, C/Arias de Velasco, s/n, 33005 Oviedo, Asturias, Spain. Electronic address: smdez@indurot.uniovi.es.
authors.forename: Susana
authors.initials: S
authors.lastname: Fernández-Menéndez
authors.affiliation: Urb. Las Pedreras 25, Vega, 33391 Gijón, Asturias, Spain. Electronic address: paco.ramos@telefonica.net.
authors.forename: F
authors.initials: F
authors.lastname: Ramos-Muñiz
authors.affiliation: Dpto. de Geología, Facultad de Ciencias Experimentales, Avda. Fuerzas Armadas, s/n, 21071 Huelva, Spain. Electronic address: pablo.cruz@dgeo.uhu.es.
authors.forename: P
authors.initials: P
authors.lastname: Cruz-Hernández
authors.affiliation: Dpto. de Explotación y Prospección de Minas, Universidad de Oviedo, C/Independencia, 13, 33004 Oviedo, Asturias, Spain. Electronic address: andresgquiros@gmail.com.
authors.forename: A
authors.initials: A
authors.lastname: González-Quirós
mesh_terms: D004784:Environmental Monitoring; D005844:Geology; D060587:Groundwater / Q000737:chemistry*; D008628:Mercury / Q000032:analysis*; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis*; D013030:Spain; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Geochemical backgrounds in soils; Isotopes; Mercury; Soil mercury leachate; Springs; Sulphate