title: A chronic bioassay with the estuarine amphipod Corophium volutator: test method description and confounding factors.
abstract: Methods of conducting a chronic sediment toxicity test with the estuarine amphipod Corophium volutator are described. They consist of a 49-day exposure, after which mortality, growth and reproduction are determined. Pilot experiments were used to optimize test design parameters such as temperature, duration, feeding and refreshing regimes, and effects of indigenous organisms. By way of further validation, the present study focused on the effects of four different parameters: oxygen saturation, salinity, ammonium and nitrite. These confounding factors might play an important role especially if the test is used for risk assessment of field-contaminated sediments. It is concluded that the present experimental design is well suited for chronic sediment exposures with C. volutator. The test can be performed at a broad range of salinity values, provided that controls are performed at the same salinity. Results further demonstrate that with the endpoints growth and reproduction this chronic test procedure is a factor 7-18 more sensitive to ammonium and nitrate than the standardized acute bioassay (endpoint mortality).
authors.affiliation: RWS, National Institute for Coastal and Marine Management (RIKZ), P.O. Box 8039, 4330 EA Middelburg, The Netherlands. M.J.vdHeuvel-Greve@rikz.rws.minvenw.nl
authors.forename: Martine
authors.initials: M
authors.lastname: van den Heuvel-Greve
authors.forename: Jaap
authors.initials: J
authors.lastname: Postma
authors.forename: Johan
authors.initials: J
authors.lastname: Jol
authors.forename: Hanneke
authors.initials: H
authors.lastname: Kooman
authors.forename: Marco
authors.initials: M
authors.lastname: Dubbeldam
authors.forename: Cor
authors.initials: C
authors.lastname: Schipper
authors.forename: Belinda
authors.initials: B
authors.lastname: Kater
mesh_terms: D033304:Amphipoda / Q000187:drug effects* / Q000254:growth & development; D000704:Analysis of Variance; D000818:Animals; D001681:Biological Assay; D004784:Environmental Monitoring / Q000379:methods*; D019015:Geologic Sediments / Q000737:chemistry*; D012098:Reproduction / Q000187:drug effects; D036401:Toxicity Tests, Chronic / Q000379:methods*; D014874:Water Pollutants, Chemical / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical