title: Establishing geochemical background levels of selected trace elements in areas having geochemical anomalies: The case study of the Orbetello lagoon (Tuscany, Italy).
abstract: The determination of background concentration values (BGVs) in areas, characterised by the presence of natural geochemical anomalies and anthropogenic impact, appears essential for a correct pollution assessment. For this purpose, it is necessary to establish a reliable method for determination of local BGVs. The case of the Orbetello lagoon, a geologically complex area characterized by Tertiary volcanism, is illustrated. The vertical concentration profiles of As, Cd, Cr, Cu, Hg, Ni, Pb and Zn were studied in four sediment cores. Local BGVs were determined considering exclusively samples not affected by anthropogenic influence, recognized by means of multivariate statistics and radiochronological dating ((137)Cs and (210)Pb). Results showed BGVs well-comparable with mean crustal or shale values for most of the considered elements except for Hg (0.87 mg/kg d.w.) and As (16.87 mg/kg d.w.), due to mineralization present in the catchment basin draining into the lagoon.
authors.affiliation: ISPRA, Italian Institute for Environmental Protection and Research, Via di Castel Romano, 100, 00128 Rome, Italy. Electronic address: elena.romano@isprambiente.it.
authors.forename: Elena
authors.initials: E
authors.lastname: Romano
authors.affiliation: ISPRA, Italian Institute for Environmental Protection and Research, Via di Castel Romano, 100, 00128 Rome, Italy.
authors.forename: Luisa
authors.initials: L
authors.lastname: Bergamin
authors.affiliation: GAU-Radioanalytical Laboratories, University of Southampton, National Oceanography Centre, Southampton, SO14 3ZH, UK.
authors.forename: Ian W
authors.initials: IW
authors.lastname: Croudace
authors.affiliation: ISPRA, Italian Institute for Environmental Protection and Research, Via di Castel Romano, 100, 00128 Rome, Italy.
authors.forename: Antonella
authors.initials: A
authors.lastname: Ausili
authors.affiliation: ISPRA, Italian Institute for Environmental Protection and Research, Via di Castel Romano, 100, 00128 Rome, Italy.
authors.forename: Chiara
authors.initials: C
authors.lastname: Maggi
authors.affiliation: ISPRA, Italian Institute for Environmental Protection and Research, Via di Castel Romano, 100, 00128 Rome, Italy.
authors.forename: Massimo
authors.initials: M
authors.lastname: Gabellini
mesh_terms: D001417:Background Radiation; D002588:Cesium Radioisotopes / Q000032:analysis; D004784:Environmental Monitoring / Q000379:methods*; D004785:Environmental Pollutants / Q000032:analysis*; D019015:Geologic Sediments / Q000737:chemistry*; D007558:Italy; D007856:Lead Radioisotopes / Q000032:analysis; D015999:Multivariate Analysis; D055110:Radiometric Dating; D014131:Trace Elements / Q000032:analysis*; D018707:Volcanic Eruptions; D014874:Water Pollutants, Chemical / Q000032:analysis
chemical_list: D002588:Cesium Radioisotopes; D004785:Environmental Pollutants; D007856:Lead Radioisotopes; D014131:Trace Elements; D014874:Water Pollutants, Chemical
keywords: Anthropogenic impact; Background value; Mercury contamination; Sediments; Trace element concentration