title: Resuspended contaminated sediments cause sublethal stress to oysters: A biomarker differentiates total suspended solids and contaminant effects.
abstract: Resuspended contaminated sediments represent an important route of contaminant exposure for aquatic organisms. During resuspension events, filter-feeding organisms are exposed to contaminants, in both the dissolved form (at the gills) and the particulate form (in the digestive system). In addition, these organisms must manage the physical stress associated with an increase in total suspended solids (TSS). To date, few studies have experimentally compared the contributions to biological stress of contaminated and clean suspended solids. The authors mixed field-collected sediments (<63 μm) from clean and contaminated field sites to create 4 treatments of increasing metal concentrations. Sydney rock oysters were then exposed to sediment treatments at different TSS concentrations for 4 d, and cellular biomarkers (lysosomal membrane stability, lipid peroxidation, and glutathione) were measured to evaluate sublethal toxicity. Lysosomal membrane stability was the most sensitive biomarker for distinguishing effects from resuspended contaminated sediments, as increasing amounts of contaminated TSS increased lysosomal membrane destabilization. The authors' results illustrate the importance of considering contaminant exposures from resuspended sediments when assessing the toxicity of contaminants to aquatic organisms.
authors: Evolution and Ecology Research Centre, School of Biological and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors: Katelyn J
authors: KJ
authors: Edge
authors: Evolution and Ecology Research Centre, School of Biological and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.
authors: Katherine A
authors: KA
authors: Dafforn
authors: Centre for Environmental Contaminants Research, Commonwealth Scientific and Industrial Research Organisation Land and Water, Kirrawee, New South Wales, Australia.
authors: Stuart L
authors: SL
authors: Simpson
authors: Department of Biology, University of North Carolina at Charlotte, Charlotte, North Carolina, USA.
authors: Amy H
authors: AH
authors: Ringwood
authors: Evolution and Ecology Research Centre, School of Biological and Environmental Sciences, University of New South Wales, Sydney, New South Wales, Australia.|Sydney Institute of Marine Science, Mosman, New South Wales, Australia.
authors: Emma L
authors: EL
authors: Johnston
mesh_terms: D000818:Animals; D015415:Biomarkers / Q000378:metabolism*; D002244:Carbon / Q000032:analysis; D004064:Digestive System / Q000187:drug effects / Q000378:metabolism; D019015:Geologic Sediments / Q000032:analysis / Q000737:chemistry*; D005880:Gills / Q000187:drug effects / Q000378:metabolism; D005978:Glutathione / Q000378:metabolism; D015227:Lipid Peroxidation / Q000187:drug effects; D008247:Lysosomes / Q000187:drug effects / Q000378:metabolism; D008670:Metals / Q000737:chemistry / Q000633:toxicity; D010125:Ostreidae / Q000187:drug effects* / Q000378:metabolism; D012989:Soil Pollutants / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D015415:Biomarkers; D008670:Metals; D012989:Soil Pollutants; D014874:Water Pollutants, Chemical; D002244:Carbon; D005978:Glutathione
keywords: Biomarkers; Contaminated sediments; Oysters; Resuspended sediments; Total suspended solids