title: Chemical and physiological metal bioaccessibility assessment in surface bottom sediments from the Deba River urban catchment: Harmonization of PBET, TCLP and BCR sequential extraction methods.
abstract: In the present study, the physiologically based extraction test PBET (gastric and intestinal phases) and two chemical based extraction methods, the toxicity characteristic leaching procedure (TCLP) and the sequential extraction procedure BCR 701 (Community Bureau of Reference of the European Commission) have been used to estimate and evaluate the bioaccessibility of metals (Fe, Mn, Zn, Cu, Ni, Cr and Pb) in sediments from the Deba River urban catchment. The statistical analysis of data and comparison among physiological and chemical methods have highlighted the relevance of simulate the gastrointestinal tract environment since metal bioaccessibility seems to depend on water and sediment properties such as pH, redox potential and organic matter content, and, primordially, on the form in which metals are present in the sediment. Indeed, metals distributed among all fractions (Mn, Ni, Zn) were the most bioaccessible, followed by those predominantly bound to oxidizable fraction (Cu, Cr and Pb), especially near major urban areas. Finally, a toxicological risk assessment was also performed by determining the hazard quotient (HQ), which demonstrated that, although sediments from mid- and downstream sampling points presented the highest metal bioaccessibilities, were not enough to have adverse effects on human health, Cr being the most potentially toxic element.
authors.affiliation: Department of Chemical and Environmental Engineering, University of the Basque Country, Alameda Urquijo z/g, Bilbao 48013, Basque Country, Spain. Electronic address: junda001@ikasle.ehu.eus.
authors.forename: Jessica
authors.initials: J
authors.lastname: Unda-Calvo
authors.affiliation: Department of Chemical and Environmental Engineering, University of the Basque Country, Alameda Urquijo z/g, Bilbao 48013, Basque Country, Spain. Electronic address: miren.martinez@ehu.eus.
authors.forename: Miren
authors.initials: M
authors.lastname: Martínez-Santos
authors.affiliation: Department of Chemical and Environmental Engineering, University of the Basque Country, Alameda Urquijo z/g, Bilbao 48013, Basque Country, Spain. Electronic address: estilita.ruiz@ehu.eus.
authors.forename: Estilita
authors.initials: E
authors.lastname: Ruiz-Romera
mesh_terms: D001682:Biological Availability; D002675:Child, Preschool; D002947:Cities; D004784:Environmental Monitoring / Q000379:methods; D019015:Geologic Sediments / Q000737:chemistry*; D006801:Humans; D019216:Metals, Heavy / Q000032:analysis* / Q000493:pharmacokinetics* / Q000633:toxicity; D018570:Risk Assessment; D045483:Rivers / Q000737:chemistry*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000493:pharmacokinetics / Q000633:toxicity
chemical_list: D019216:Metals, Heavy; D014874:Water Pollutants, Chemical
keywords: Bioaccessibility; Health assessment; Physiological test; Sediments; Urban catchment