title: Retrospective monitoring of mercury in fish from selected European freshwater and estuary sites.
abstract: Levels and trends of total mercury (THg) and methylmercury (MeHg) compounds in bream (Abramis brama) from different European sites were compared. Bream were collected between 2007 and 2013 in the estuaries of the rivers Scheldt (Netherlands), Rhône (France), Göta älv (Sweden), Tees (United Kingdom), and Mersey (UK), and in Lake Belau (Germany). A direct mercury analyzer was used to determine THg concentrations while MeHg was measured by gas chromatography/inductively coupled plasma-mass spectrometry applying stable isotope dilution. THg and MeHg in annual pool samples of bream ranged between 15.9 and 251 μg kg(-1) wet weight (ww) with lowest concentrations found at the reference site Lake Belau and highest in samples from the river Rhône. The EU environmental quality standard (EQS) of 20 μg kg(-1) ww was exceeded at all sites and in all years except at Lake Belau in 2012. Significantly decreasing trends over time were observed only in bream from the Rhône, while THg increased in bream from the Western Scheldt. The MeHg fractions of THg were always >80% and a significant difference between sites was detected only in one case (Rhône vs. Lake Belau).
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (Fraunhofer IME), 57392 Schmallenberg, Germany.
authors.forename: Regine
authors.initials: R
authors.lastname: Nguetseng
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (Fraunhofer IME), 57392 Schmallenberg, Germany.
authors.forename: Annette
authors.initials: A
authors.lastname: Fliedner
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (Fraunhofer IME), 57392 Schmallenberg, Germany. Electronic address: burkhard.knopf@ime.fraunhofer.de.
authors.forename: Burkhard
authors.initials: B
authors.lastname: Knopf
authors.affiliation: UMR Littoral, Environnement et Sociétés (LIENSs), CNRS - Université de La Rochelle, Institut du littoral et de l'environnement, 17000 La Rochelle, France.
authors.forename: Benoit
authors.initials: B
authors.lastname: Lebreton
authors.affiliation: Department of Biogeography, Trier University, 54286 Trier, Germany.
authors.forename: Markus
authors.initials: M
authors.lastname: Quack
authors.affiliation: Fraunhofer Institute for Molecular Biology and Applied Ecology (Fraunhofer IME), 57392 Schmallenberg, Germany.
authors.forename: Heinz
authors.initials: H
authors.lastname: Rüdel
mesh_terms: D000818:Animals; D004784:Environmental Monitoring / Q000379:methods*; D063366:Estuaries; D005399:Fishes; D005618:Fresh Water / Q000737:chemistry*; D008628:Mercury / Q000032:analysis*; D008767:Methylmercury Compounds / Q000032:analysis; D014874:Water Pollutants, Chemical / Q000032:analysis*
chemical_list: D008767:Methylmercury Compounds; D014874:Water Pollutants, Chemical; D008628:Mercury
keywords: Abramis brama; Biota monitoring; Environmental quality standard; Mercury; Methylmercury; Trend monitoring