title: Bioavailability of CeO2 and SnO2 nanoparticles evaluated by dietary uptake in the earthworm Eisenia fetida and sequential extraction of soil and feed.
abstract: The growing number of nanotechnology products on the market will inevitably lead to the release of engineered nanomaterials with potential risk to humans and environment. This study set out to investigate the exposure of soil biota to engineered nanoparticles (NPs). Cerium dioxide (CeO2 NPs) and tin dioxide nanoparticles (SnO2 NPs) were radiolabelled using neutron activation, and employed to assess the uptake and excretion kinetics in the earthworm Eisenia fetida. Through sequential extraction, NPs bioavailability in two contrasting soils and in earthworm feed was also investigated. Neither CeO2 NPs nor SnO2 NPs bioaccumulated in earthworms, and both were rapidly excreted when worms were transferred to clean soil. Low bioavailability was also indicated by low amounts of NPs recovered during extraction with non-stringent extractants. CeO2 NPs showed increasing mobility in organic soil over time (28 days), indicating that organic matter has a strong influence on the fate of CeO2 NPs in soil.
authors.affiliation: Department of Agricultural Sciences, University of Bologna, Alma Mater Studiorum, Viale Fanin 40, 40127 Bologna, Italy. Electronic address: serena.carbone2@unibo.it.
authors.forename: Serena
authors.initials: S
authors.lastname: Carbone
authors.affiliation: Centre for Environmental Radioactivity (CERAD), Department of Environmental Sciences, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Aas, Norway.
authors.forename: Turid
authors.initials: T
authors.lastname: Hertel-Aas
authors.affiliation: Norwegian Institute for Bioeconomy Research (NIBIO), Environment and Climate Department, Høyskoleveien 7, N-1431 Aas, Norway.
authors.forename: Erik J
authors.initials: EJ
authors.lastname: Joner
authors.affiliation: Centre for Environmental Radioactivity (CERAD), Department of Environmental Sciences, Norwegian University of Life Sciences, P.O. Box 5003, N-1432 Aas, Norway.
authors.forename: Deborah H
authors.initials: DH
authors.lastname: Oughton
mesh_terms: D000818:Animals; D002563:Cerium / Q000032:analysis / Q000378:metabolism*; D053768:Metal Nanoparticles / Q000032:analysis*; D009835:Oligochaeta / Q000378:metabolism*; D012987:Soil; D012989:Soil Pollutants / Q000032:analysis / Q000378:metabolism*; D017971:Tin Compounds / Q000032:analysis / Q000378:metabolism*
chemical_list: D012987:Soil; D012989:Soil Pollutants; D017971:Tin Compounds; D002563:Cerium; C030583:ceric oxide; C045358:stannic oxide
keywords: Cerium nanoparticles; Earthworms; Ecotoxicity; Exposure assessment; Tin nanoparticles