title: Toxicity and bioaccumulation of sediment-associated silver nanoparticles in the estuarine polychaete, Nereis (Hediste) diversicolor.
abstract: In this study, the toxicities of sediment-associated silver added to sediment as commercially available silver nanoparticles (Ag NPs, 20 and 80 nm) and aqueous Ag (AgNO3) to the estuarine polychaete, Nereis (Hediste) diversicolor, were investigated for both individual and subcellular endpoints after 10 d of exposure. Both Ag NP types were characterized in parallel to the toxicity studies and found to be polydispersed and overlapping in size. Burrowing activity decreased (marginally) with increasing Ag concentration and depended on the form of Ag added to sediment. All worms accumulated Ag regardless of the form in which it was added to the sediment, and worm size (expressed as dry weight) was found to significantly affect bioaccumulation such that smaller worms accumulated more Ag per body weight than larger worms. Lysosomal membrane permeability (neutral red retention time, NRRT) and DNA damage (comet assay tail moment and tail DNA intensity %) of Nereis coelomocytes increased in a concentration-dependent manner in all three Ag treatments. Ag NP treatments were more toxic than aqueous Ag for all toxicity endpoints, even though bioaccumulation did not differ significantly among Ag forms. No significant difference in toxicity was observed between the two Ag NP treatments which was attributed to their overlap in particle size.
authors.affiliation: Department of Environmental Social and Spatial Change (ENSPAC), Roskilde University, PO Box 260, 4000 Roskilde, Denmark; National Marine Environmental Monitoring Center, Dalian 116023, China. Electronic address: ycong@nmemc.gov.cn.
authors.forename: Yi
authors.initials: Y
authors.lastname: Cong
authors.affiliation: Department of Environmental Social and Spatial Change (ENSPAC), Roskilde University, PO Box 260, 4000 Roskilde, Denmark. Electronic address: banta@ruc.dk.
authors.forename: Gary T
authors.initials: GT
authors.lastname: Banta
authors.affiliation: Department of Environmental Social and Spatial Change (ENSPAC), Roskilde University, PO Box 260, 4000 Roskilde, Denmark. Electronic address: selck@ruc.dk.
authors.forename: Henriette
authors.initials: H
authors.lastname: Selck
authors.affiliation: Department of Mineralogy, Natural History Museum, London SW7 5BD, UK. Electronic address: d.berhanu@nhm.ac.uk.
authors.forename: Deborah
authors.initials: D
authors.lastname: Berhanu
authors.affiliation: Department of Mineralogy, Natural History Museum, London SW7 5BD, UK; School of Geography, Earth and Environmental Sciences (GEES), University of Birmingham, Edgbaston, Birmingham B15 2TT, UK. Electronic address: e.valsami-jones@nhm.ac.uk.
authors.forename: Eugenia
authors.initials: E
authors.lastname: Valsami-Jones
authors.affiliation: Department of Environmental Social and Spatial Change (ENSPAC), Roskilde University, PO Box 260, 4000 Roskilde, Denmark; School of Biological Sciences, University of Nebraska Lincoln, 348 Manter Hall, Lincoln, NE 68588-0118, USA. Electronic address: vforbes3@unlnotes.unl.edu.
authors.forename: Valery E
authors.initials: VE
authors.lastname: Forbes
mesh_terms: D000818:Animals; D020552:Comet Assay; D004249:DNA Damage / Q000187:drug effects; D019015:Geologic Sediments / Q000737:chemistry*; D053758:Nanoparticles / Q000633:toxicity*; D010316:Particle Size; D011077:Polychaeta / Q000187:drug effects* / Q000378:metabolism; D012834:Silver / Q000378:metabolism / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000378:metabolism / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical; D012834:Silver
keywords: Ag body burden; Burrowing behavior; DNA damage; Lysosomal membrane stability; Sediment exposure; Silver nanoparticles