title: Distribution coefficients of potentially toxic elements in soils from the eastern Amazon.
abstract: The solid-solution distribution or partition coefficient (Kd) is a measure of affinity of potentially toxic elements (PTE) for soil colloids. Kd plays a key role in several models for defining PTE guideline values in soils and for assessing environmental risks, and its value depends on edaphic and climatic conditions of the sites where the soils occur. This study quantified Kd values for Cd, Co, Cr, Cu, Hg, Ni, Pb, and Zn from representative soil samples from Brazil's eastern Amazon region, which measures 1.2 million km(2). The Kd values obtained were lower than those set by both international and Brazilian environmental agencies and were correlated with the pH, Fe and Mn oxide content, and cationic exchange capacity of the soils. The following order of decreasing affinity was observed: Pb>Cu>Hg>Cr>Cd≈Co>Ni>Zn.
authors.affiliation: Department of Soil Science, Luiz de Queiroz School of Agriculture, University of São Paulo (ESALQ-USP), C.P. 9, Piracicaba, 13418-900, SP, Brazil, andersonbraz@usp.br.
authors.forename: Anderson Martins
authors.initials: AM
authors.lastname: de Souza Braz
authors.forename: Antonio Rodrigues
authors.initials: AR
authors.lastname: Fernandes
authors.forename: José Roberto
authors.initials: JR
authors.lastname: Ferreira
authors.forename: Luís Reynaldo Ferracciú
authors.initials: LR
authors.lastname: Alleoni
mesh_terms: D001938:Brazil; D004784:Environmental Monitoring; D015386:Hazardous Substances / Q000032:analysis* / Q000633:toxicity; D019216:Metals, Heavy / Q000032:analysis / Q000633:toxicity; D012987:Soil / Q000737:chemistry*; D012989:Soil Pollutants / Q000032:analysis* / Q000633:toxicity
chemical_list: D015386:Hazardous Substances; D019216:Metals, Heavy; D012987:Soil; D012989:Soil Pollutants