title: Assessing contamination levels of Laguna Lake sediments (Philippines) using a contact assay with zebrafish (Danio rerio) embryos.
abstract: The present study investigated the suitability of a sediment contact assay using zebrafish (Danio rerio) embryos to evaluate the degree of lake sediment contamination. As endpoints, developmental parameters (mortality, abnormality, heart rate, and hatching rate) as well as stress protein responses (hsp 70 levels) in the developing embryos were recorded during a 96-h exposure. Fertilized zebrafish eggs were exposed to both the whole as well as organic extract concentrations prepared from collected sediments from 5 sites along Laguna Lake, Philippines. Compared to whole sediment exposure, more severe embryotoxic and teratogenic responses were elicited in embryos exposed to organic extracts. However, since whole sediment-exposed embryos also revealed significant developmental defects, this exposure phase served as the more realistic exposure scenario in our study. Weak to strong upregulation of hsp 70 levels was also registered among embryos exposed to both whole sediments and organic extracts. The observed embryotoxic and proteotoxic responses by zebrafish embryos to Laguna Lake sediment exposures were discussed in relation to the analyzed contaminants in the sediments (heavy metals, PAHs (perylene), solvent). Overall, the present study points out that the sediment contact assay with zebrafish embryos offers a practicable and highly sensitive bioassay for the general assessment of sediment toxicity.
authors.affiliation: Animal Physiological Ecology, University of Tübingen, Konrad-Adenauer-Str 20, Tübingen, Germany. arnold.v.hallare@uni-tuebingen.de
authors.forename: A V
authors.initials: AV
authors.lastname: Hallare
authors.forename: T
authors.initials: T
authors.lastname: Kosmehl
authors.forename: T
authors.initials: T
authors.lastname: Schulze
authors.forename: H
authors.initials: H
authors.lastname: Hollert
authors.forename: H-R
authors.initials: HR
authors.lastname: Köhler
authors.forename: R
authors.initials: R
authors.lastname: Triebskorn
mesh_terms: D000818:Animals; D002244:Carbon / Q000032:analysis; D004625:Embryo, Nonmammalian / Q000002:abnormalities / Q000378:metabolism; D004784:Environmental Monitoring; D005618:Fresh Water; D019015:Geologic Sediments; D018840:HSP70 Heat-Shock Proteins / Q000378:metabolism*; D019216:Metals, Heavy / Q000032:analysis; D010679:Philippines; D011084:Polycyclic Aromatic Hydrocarbons / Q000032:analysis; D015996:Survival Rate; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*; D015027:Zebrafish / Q000002:abnormalities / Q000196:embryology* / Q000378:metabolism
chemical_list: D018840:HSP70 Heat-Shock Proteins; D019216:Metals, Heavy; D011084:Polycyclic Aromatic Hydrocarbons; D014874:Water Pollutants, Chemical; D002244:Carbon