title: Investigation of copper speciation in pig slurry by a multitechnique approach.
abstract: It is now well-known that copper (Cu) can accumulate on the surface of soils upon which pig slurry has been applied. This is due to the high quantity of Cu in pig slurry resulting from its use as a growth promoter in animal feeds. The mobility and bioavailability of Cu from pig slurry spreading can be better predicted by determining the speciation of this element in addition to its total concentration. The aim of this study was to present a multitechnique approach to investigate Cu speciation in pig slurry. First, size fractionation and chemical characterization of each size fraction were performed to complement results obtained in raw samples. Micro X-ray fluorescence spectroscopy (μXRF) highlighted the colocalization of Cu and sulfur (S). Finally, X-ray absorption near-edge structure spectroscopy (XANES) showed that Cu speciation in raw pig slurry and size fractions could be described by Cu(2)S and that its oxidation state is Cu(I). In addition, geochemical calculation demonstrated that chalcocite (Cu(2)S) was the major Cu species present under pig slurry lagoon physical-chemical conditions. This Cu speciation in pig slurry may be the main reason for the observed Cu accumulation at the soil surface.
authors.affiliation: CIRAD, UPR Recyclage et risque, Réunion, France.
authors.forename: Samuel
authors.initials: S
authors.lastname: Legros
authors.forename: Perrine
authors.initials: P
authors.lastname: Chaurand
authors.forename: Jérôme
authors.initials: J
authors.lastname: Rose
authors.forename: Armand
authors.initials: A
authors.lastname: Masion
authors.forename: Valérie
authors.initials: V
authors.lastname: Briois
authors.forename: Jean-Henry
authors.initials: JH
authors.lastname: Ferrasse
authors.forename: Hervé Saint
authors.initials: HS
authors.lastname: Macary
authors.forename: Jean-Yves
authors.initials: JY
authors.lastname: Bottero
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Doelsch
mesh_terms: D000818:Animals; D005591:Chemical Fractionation; D003300:Copper / Q000302:isolation & purification*; D052918:Environmental Restoration and Remediation / Q000379:methods*; D006863:Hydrogen-Ion Concentration; D010316:Particle Size; D012015:Reference Standards; D012722:Sewage / Q000737:chemistry*; D034421:Sus scrofa; D056928:X-Ray Absorption Spectroscopy
chemical_list: D012722:Sewage; D003300:Copper