Are parasites of Phycis blennoides (Gadiformes: Phycidae) good indicators of metal pollution in the Western Mediterranean deep- sea? C. M. Moyà-Alcover1, M. Nachev2, S. Zimmermann2, F. E. Montero1,3, M. Carrassón1 B. Sures2 and A. Pérez-del-Olmo1,2,3* 1Departament de Biologia Animal, de Biologia Vegetal i d'Ecologia, Universitat Autònoma de Barcelona, 08193 Cerdanyola del Vallès, Barcelona, Spain 2 Institute of Biology, Zoology/Hydrobiology, University Duisburg-Essen, Universitätsstr. 5, D- 45141 Essen, Germany 3 Unitat de Zoologia Marina, Institut Cavanilles de Biodiversitat i Biologia Evolutiva, Parc Científic, Universitat de València, Aptdo 22085, E-46071-Valencia, Spain * Presenting author contact: [email protected] In the last years the general concern about the significance of trace elements in the environment has rapidly increased. The alteration of the global cycles of trace elements as a consequence of a growing anthropogenic activity has enhanced natural concentrations of these elements in the marine environment, especially in coastal areas. But these contaminants can affect not only the littoral sediments but also deeper areas due to its transportation together with particulate matter. While coastal regions are relatively well characterised from a pollution perspective, the deep-sea areas are relatively unknown. A variety of organisms have been investigated to evaluate their potential as biological indicators of different forms of pollution in the aquatic environment and some fish parasites has been demonstrated to be useful because of their ability to bioconcentrate these pollutants even at much higher levels than free-living organisms. However, few studies have been carried out in the marine environment and studies from deep-sea are virtually lacking. The aim of this study was to assess the usefulness of parasites of Phycis blennoides as indicators of metal pollution in the Western Mediterranean deep-sea. The most prevalent species of this host were selected: Diclidophora phycidis, Lepidapedon sp., Echinorhynchus sp. and Clavella alata. The mean bioconcentration factors revealed that As was the only element present in lower concentrations in all parasite species compared with both host tissues analysed (muscle and liver). Mean accumulation capacity for the other elements (Cd, Co, Cu, Cr, Fe, Mn, Pb, V, Zn) were much higher in the four parasite species than in fish muscle. With respect to host liver, bioconcentration factors showed more heterogeneity, Lepidapedon sp. bioconcentrated more (seven) elements, followed by C. clavata and Echinorhynchus sp. (five elements) and D. phycidis (three elements). Funding for this work was obtained from the projects Biomare CTM2006-28145 and ANTROMARE CTM2009-12214-C02-02. C. M. Moyà-Alcover benefits from a FPU fellowship Ministerio de Ciencia e Innovación and A. Perez-del-Olmo from a Marie Curie Intra European Fellowship PIEF-GA-2009-236127. .