title: Ambient trace element background concentrations in soils and their use in risk assessment.
abstract: The definition of ambient background concentrations (ABCs) is used in this study to assess the potential environmental risk of trace elements in soils and parent materials from Granada, Spain. Two different layers of soil (0-20 and 20-40 cm) and parent material samples were collected at 93 sites. From cumulative frequency distribution curves, ABCs for As, Co, Cu, Cr, Ni, Pb and Zn were estimated at 3.5-20, 7-23, 13-25.6, 29-66, 7-20, 15-36, and 5.5-76 mg kg(-1), respectively. Tukey box-plots were used to discriminate different concentration classes and identify potentially contaminated sites. Weakly-weathered soils (Entisols) over carbonate materials showed the lowest background contents, the most developed soils (Alfisols) over metamorphic rocks the highest ones. Outliers were mainly found near a former iron mine where arsenic concentrations were by far exceeding the corresponding regional ABC. These soils were however, not toxic to Escherichia coli and Vibrio fischeri. The prediction of site-specific ABCs together with bioavailability and toxicity assessment is a valuable tool for giving further insight into the risk of trace elements in soils.
authors.affiliation: Institute of Ecological Science, VU University; De Boelelaan 1085, 1081 HV Amsterdam, The Netherlands. maria.diez@falw.vu.nl
authors.forename: M
authors.initials: M
authors.lastname: Díez
authors.forename: M
authors.initials: M
authors.lastname: Simón
authors.forename: F
authors.initials: F
authors.lastname: Martín
authors.forename: C
authors.initials: C
authors.lastname: Dorronsoro
authors.forename: I
authors.initials: I
authors.lastname: García
authors.forename: C A M
authors.initials: CA
authors.lastname: Van Gestel
mesh_terms: D048908:Aliivibrio fischeri / Q000187:drug effects; D004784:Environmental Monitoring; D004926:Escherichia coli / Q000187:drug effects; D018570:Risk Assessment; D012987:Soil / Q000032:analysis* / Q000592:standards; D012989:Soil Pollutants / Q000032:analysis* / Q000633:toxicity; D013030:Spain; D018675:Toxicity Tests; D014131:Trace Elements / Q000032:analysis* / Q000633:toxicity
chemical_list: D012987:Soil; D012989:Soil Pollutants; D014131:Trace Elements