title: Spatial distribution of potentially bioavailable metals in surface soils of a contaminated sports ground in Galway, Ireland.
abstract: Assessing the environmental risk of metal contamination in soils requires the determination of both total (TCs) and bioavailable (BCs) element concentrations. A total of 200 surface (0-10 cm) soil samples were collected from an urban sports ground (South Park) in Galway, Ireland, a former landfill and dumping site, which is currently under remediation. The potential BCs of metals were measured using ethylene-diamine-tetra-acetic acid (EDTA) extraction followed by inductively coupled plasma-optical emission spectrometry analysis, while the TCs were determined using portable X-ray fluorescence spectrometry. It was found that Zn was primarily present in the insoluble residue (EDTA un-extractable) fraction in soils, with the median ratio of BCs/TCs 0.27. However, Pb and Cu had higher ratios of BCs/TCs (median values of 0.60 and 0.39, respectively) suggesting that they are potentially more bioavailable in the soils. The spatial distribution maps showed that both TCs and BCs for Cu, Pb and Zn in the study area were spatially heterogeneous. It was found that the BCs exhibited generally similar spatial patterns as their TCs of Cu, Pb and Zn: high values were mainly located in the west, north-east and south-east portions of the study area, where only a thin layer of topsoil existed. It was recommended that the current remediation action for this site needs to be carried out on an urgent basis.
authors.affiliation: GIS Centre, Ryan Institute and School of Geography and Archaeology, National University of Ireland, Galway, Ireland.
authors.forename: Ligang
authors.initials: L
authors.lastname: Dao
authors.forename: Liam
authors.initials: L
authors.lastname: Morrison
authors.forename: Ger
authors.initials: G
authors.lastname: Kiely
authors.forename: Chaosheng
authors.initials: C
authors.lastname: Zhang
mesh_terms: D003300:Copper / Q000032:analysis / Q000737:chemistry; D004784:Environmental Monitoring; D052918:Environmental Restoration and Remediation; D007494:Ireland; D007854:Lead / Q000032:analysis / Q000737:chemistry; D019216:Metals, Heavy / Q000032:analysis* / Q000737:chemistry; D012989:Soil Pollutants / Q000032:analysis* / Q000737:chemistry; D013052:Spectrometry, X-Ray Emission; D013177:Sports; D015032:Zinc / Q000032:analysis / Q000737:chemistry
chemical_list: D019216:Metals, Heavy; D012989:Soil Pollutants; D007854:Lead; D003300:Copper; D015032:Zinc