[1] Senckenberg Res Inst, Dept River Ecol & Conservat, D-60325 Frankfurt, Germany
[2] Nat Hist Museum, D-60325 Frankfurt, Germany
[3] Goethe Univ Frankfurt, Fac Biol Sci, Dept Aquat Ecotoxicol, Frankfurt, Germany
[4] Goethe Univ Frankfurt, Fac Geosci & Geog, Dept Environm Analyt Chem, Frankfurt, Germany
[5] Food GmbH Jena Analytik Consulting, Jena, Germany