title: A microcosm study to support aquatic risk assessment of nickel: Community-level effects and comparison with bioavailability-normalized species sensitivity distributions.
abstract: The aquatic risk assessment for nickel (Ni) in the European Union is based on chronic species sensitivity distributions and the use of bioavailability models. To test whether a bioavailability-based safe threshold of Ni (the hazardous concentration for 5% of species [HC5]) is protective for aquatic communities, microcosms were exposed to 5 stable Ni treatments (6-96 μg/L) and a control for 4 mo to assess bioaccumulation and effects on phytoplankton, periphyton, zooplankton, and snails. Concentrations of Ni in the periphyton, macrophytes, and snails measured at the end of the exposure period increased in a dose-dependent manner but did not indicate biomagnification. Abundance of phytoplankton and snails decreased in 48 μg Ni/L and 96 μg Ni/L treatments, which may have indirectly affected the abundance of zooplankton and periphyton. Exposure up to 24 μg Ni/L had no adverse effects on algae and zooplankton, whereas the rate of population decline of the snails at 24 μg Ni/L was significantly higher than in the controls. Therefore, the study-specific overall no-observed-adverse-effect concentration (NOAEC) is 12 μg Ni/L. This NOAEC is approximately twice the HC5 derived from a chronic species sensitivity distribution considering the specific water chemistry of the microcosm by means of bioavailability models. Thus, the present study provides support to the protectiveness of the bioavailability-normalized HC5 for freshwater communities.
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Schmallenberg, Hochsauerlandkreis, Germany.
authors.forename: Udo
authors.initials: U
authors.lastname: Hommen
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Schmallenberg, Hochsauerlandkreis, Germany.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Knopf
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Schmallenberg, Hochsauerlandkreis, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Rüdel
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology IME, Schmallenberg, Hochsauerlandkreis, Germany.
authors.forename: Christoph
authors.initials: C
authors.lastname: Schäfers
authors.affiliation: Environmental Toxicology Unit (GhEnToxLab), Ghent University, Ghent, East Flanders, Belgium.
authors.forename: Karel
authors.initials: K
authors.lastname: De Schamphelaere
authors.affiliation: Nickel Producers Environmental Research Association, Durham, North Carolina, USA.
authors.forename: Chris
authors.initials: C
authors.lastname: Schlekat
authors.affiliation: Nickel Producers Environmental Research Association, Durham, North Carolina, USA.
authors.forename: Emily Rogevich
authors.initials: ER
authors.lastname: Garman
mesh_terms: D000818:Animals; D059001:Aquatic Organisms / Q000378:metabolism*; D001682:Biological Availability; D058448:Biota; D005618:Fresh Water; D019684:Magnoliopsida / Q000378:metabolism; D009532:Nickel / Q000378:metabolism*; D010839:Phytoplankton / Q000378:metabolism; D012908:Snails / Q000378:metabolism; D013045:Species Specificity; D014874:Water Pollutants, Chemical / Q000378:metabolism*; D015048:Zooplankton / Q000378:metabolism
chemical_list: D014874:Water Pollutants, Chemical; D009532:Nickel
keywords: Biotic ligand model; Chronic exposure; Community-level effect; Higher tier test; Metal