title: Maternal transfer of emerging brominated and chlorinated flame retardants in European eels.
abstract: The European eel (Anguilla anguilla) is regarded as a critically endangered species. Scientists are in agreement that the "quality of spawners" is a vital factor for the survival of the species. This quality can be impaired by parasites, disease and pollution. Especially endocrine disrupting organic chemicals pose a potential threat to reproduction and development of offspring. To our knowledge, the findings in this publication for the first time describe maternal transfer of contaminants in eels. We analysed the concentrations of in total 53 polybrominated diphenyl ethers (PBDEs) and their halogenated substitutes in muscle, gonads and eggs of artificially matured European eels and in muscle and gonads of untreated European eels that were used for comparison. We found evidence that persistent organic pollutants such as PBDEs, as well as their brominated and chlorinated substitutes are redistributed from muscle tissue to gonads and eggs. Concentrations ranged from 0.001 ng g(-1)ww for sum Dechlorane metabolites (DPMA, aCL10DP, aCl11DP) to 2.1 ng g(-1)ww for TBA in eggs, 0.001 ng g(-1)ww for Dechlorane metabolites to 9.4 ng g(-1)ww for TBA in gonads and 0.002 ng g(-1)ww for Dechlorane metabolites to 54 ng g(-1)ww for TBA in muscle tissue. Average egg muscle ratios (EMRs) for compounds detectable in artificially matured eels from both Schlei Fjord and Ems River ranged from 0.01 for Dechlorane 602 (DDC-DBF) to 10.4 for PBEB. Strong correlations were found between flame retardant concentrations and lipid content in the analysed tissue types, as well as transfer rates and octanol-water partitioning coefficient, indicating that these parameters were the driving factors for the observed maternal transfer. Furthermore, indications were found, that TBP-DBPE, TBP-AE, BATE and TBA have a significant uptake from the surrounding water, rather than just food and might additionally be formed by metabolism or biotransformation processes. Dechloranes seem to be of increasing relevance as contaminants in eels and are transferred to eggs. A change of the isomer pattern in comparison to the technical product of Dechlorane Plus (DP) was observed indicating a redistribution of DP from muscle tissue to gonads during silvering with a preference of the syn-isomer. The highly bioaccumulative DDC-DBF was the most abundant Dechlorane in all fish of the comparison group even though it is not produced or imported in the EU. The aldrin related "experimental flame retardant" dibromoaldrin (DBALD) was detected for the first time in the environment in similar or higher concentrations than DP.
authors.affiliation: Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht, Germany; Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg. Electronic address: roxana.suehring@hzg.de.
authors.forename: Roxana
authors.initials: R
authors.lastname: Sühring
authors.affiliation: Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg.
authors.forename: Marko
authors.initials: M
authors.lastname: Freese
authors.affiliation: Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg.
authors.forename: Mandy
authors.initials: M
authors.lastname: Schneider
authors.affiliation: Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg.
authors.forename: Sophia
authors.initials: S
authors.lastname: Schubert
authors.affiliation: Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg.
authors.forename: Jan-Dag
authors.initials: JD
authors.lastname: Pohlmann
authors.affiliation: Water Science and Technology Directorate, Environment Canada, Burlington, Ontario, L7R4A6 Canada.
authors.forename: Mehran
authors.initials: M
authors.lastname: Alaee
authors.affiliation: Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht, Germany; Leuphana University Lüneburg, Institute of Sustainable and Environmental Chemistry, Scharnhorststraße 1, 21335 Lüneburg.
authors.forename: Hendrik
authors.initials: H
authors.lastname: Wolschke
authors.affiliation: Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg.
authors.forename: Reinhold
authors.initials: R
authors.lastname: Hanel
authors.affiliation: Helmholtz-Zentrum Geesthacht, Centre for Materials and Coastal Research, Institute of Coastal Research, Department for Environmental Chemistry, Max-Planck-Strasse 1, 21502 Geesthacht, Germany.
authors.forename: Ralf
authors.initials: R
authors.lastname: Ebinghaus
authors.affiliation: Thünen Institute of Fisheries Ecology, Palmaille 9, 22767 Hamburg.
authors.forename: Lasse
authors.initials: L
authors.lastname: Marohn
mesh_terms: D000811:Anguilla / Q000378:metabolism*; D000818:Animals; D004784:Environmental Monitoring; D005260:Female; D005411:Flame Retardants / Q000378:metabolism*; D055768:Halogenated Diphenyl Ethers / Q000378:metabolism; D006846:Hydrocarbons, Halogenated / Q000378:metabolism*; D018811:Maternal Exposure; D014874:Water Pollutants, Chemical / Q000378:metabolism*
chemical_list: D005411:Flame Retardants; D055768:Halogenated Diphenyl Ethers; D006846:Hydrocarbons, Halogenated; D014874:Water Pollutants, Chemical
keywords: Alternate BFRs; DBALD; Dechloranes; EMRs; European eels; Flame retardants; Maternal transfer