title: Field data reveal low critical chemical concentrations for river benthic invertebrates.
abstract: River ecosystems are of immense ecological and social importance. Despite the introduction of wastewater treatment plants and advanced chemical authorization procedures in Europe, chemical pollution is still a major threat to freshwater ecosystems. Here, large-scale monitoring data was exploited to identify taxon-specific chemical concentrations beyond which benthic invertebrate taxa are unlikely to occur using Threshold Indicator Taxa Analysis (TITAN). 365 invertebrate taxa and 25 organic chemicals including pesticides, pharmaceuticals, plasticisers, flame retardants, complexing agents, a surfactant and poly- and monocyclic aromatic hydrocarbons from a total of 399 sites were analysed. The number of taxa that responded to each of these chemicals varied between 0% and 21%. These sensitive taxa belonged predominantly to the groups Plecoptera, Coleoptera, Trichoptera, Ephemeroptera, Turbellaria, Megaloptera, Crustacea, and Diptera. Strong effects were observed in response to wastewater-associated compounds, confirming that wastewater is an important cause of biological degradation. The majority of change points identified for each compound were well below predicted no-effect concentrations derived from laboratory toxicity studies. Thus, the results show that chemicals are likely to induce effects in the environment at concentrations much lower than expected based on laboratory experiments. Overall, it is confirmed that chemical pollution is still an important factor shaping the distribution of invertebrate taxa, suggesting the need for continued efforts to reduce chemical loads in rivers.
authors.affiliation: Senckenberg Research Institute and Natural History Museum Frankfurt, Department of River Ecology and Conservation, Clamecystrasse 12, 63571 Gelnhausen, Germany; Goethe University Frankfurt am Main, Faculty of Biology, Department Aquatic Ecotoxicology, Max-von-Laue-Str. 13, 60438 Frankfurt am Main, Germany. Electronic address: elisabeth.berger@senckenberg.de.
authors.forename: Elisabeth
authors.initials: E
authors.lastname: Berger
authors.affiliation: Senckenberg Research Institute and Natural History Museum Frankfurt, Department of River Ecology and Conservation, Clamecystrasse 12, 63571 Gelnhausen, Germany; University of Duisburg-Essen, Faculty of Biology, Department of River and Floodplain Ecology, Essen, Germany.
authors.forename: Peter
authors.initials: P
authors.lastname: Haase
authors.affiliation: Goethe University Frankfurt am Main, Faculty of Biology, Department Aquatic Ecotoxicology, Max-von-Laue-Str. 13, 60438 Frankfurt am Main, Germany.
authors.forename: Matthias
authors.initials: M
authors.lastname: Oetken
authors.affiliation: Senckenberg Research Institute and Natural History Museum Frankfurt, Department of River Ecology and Conservation, Clamecystrasse 12, 63571 Gelnhausen, Germany.
authors.forename: Andrea
authors.initials: A
authors.lastname: Sundermann
mesh_terms: D000818:Animals; D017753:Ecosystem; D004784:Environmental Monitoring / Q000592:standards*; D005060:Europe; D007448:Invertebrates / Q000502:physiology*; D045483:Rivers / Q000737:chemistry; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D014874:Water Pollutants, Chemical
keywords: Environmental quality standard; Macroinvertebrate; Stream; Threshold; Water framework directive