Baseline Early contamination of European flounder (Platichthys flesus) by PCDD/Fs and dioxin-like PCBs in European waters Margarida Nunes a,b,⇑ , Filipe Martinho a , Anaïs Vernisseau c , Philippe Marchand c , Bruno Le Bizec c , Henk W. van der Veer d , Henrique N. Cabral e , Fernando Ramos b , Miguel A. Pardal a a CFE – Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Apartado 3046, 3001-401 Coimbra, Portugal b CEF – Center for Pharmaceutical Studies, Health Sciences Campus, Bromatology Laboratory, Pharmacy Faculty, University of Coimbra, Azinhaga de Santa Comba, 3000-548 Coimbra, Portugal c LUNAM Université, Oniris, Laboratoire d’Étude des Résidus et Contaminants dans les Aliments (LABERCA), CS50707, F-44307 Nantes, France d NIOZ – Royal Netherlands Institute for Sea Research, PO Box 59, 1790 AB Den Burg Texel, The Netherlands e Centro de Oceanografia, Faculdade de Ciências da Universidade de Lisboa, Campo Grande, 1749-016 Lisboa, Portugal article info Article history: Available online xxxx Keywords: PCDD/Fs PCBs Fish Flounder Juvenile Atlantic abstract Contamination levels and profiles of 7 polychlorinated-p-dioxins, 10 polychlorinated furans (PCDD/Fs) and 12 dioxin-like polychlorinated biphenyls (dl-PCBs) were investigated in juvenile European flounder (Platichthys flesus) captured in different nursery areas in the northeastern Atlantic coast across its geo- graphical distribution range. The toxic equivalent concentrations (WHO-TEQ fish ) were also determined in order to evaluate which P. flesus population was more exposed to dioxin-like toxicity. Juveniles caught in the Sørfjord (Norway) showed the lowest WHO-TEQ fish concentration (0.052 pg WHO-TEQ fish g À1 wet weight) whereas the highest value was observed in fish from the Wadden Sea (The Netherlands; 0.291 pg WHO-TEQ fish g À1 ww), mainly due to the greater contribution of 2,3,7,8-tetrachlorodibenzo-p-dioxin, the most toxic congener. Nonetheless, when comparing the results with existent tissue residue-based toxic- ity benchmarks, no adverse effects resulting from PCDD/Fs and dl-PCBs are expected to occur in flounder from the studied systems. Ó 2014 Elsevier Ltd. All rights reserved. The European flounder Platichthys flesus (Linnaeus 1758) is an abundant flatfish species commonly found in coastal waters of the northeastern Atlantic Ocean, with a latitudinal distribution range from 40 to 72°N(Wheeler, 1978; Martinho et al., 2013). This species supports an important commercial fishery in the northeast Atlantic with an estimated global annual catch above 18,000 tons between 2000 and 2011 (FAO, 2011). Regarding life cycle, P. flesus spawn in marine waters and the pelagic larvae migrate to inshore to settle in shallow coastal and estuarine habitats, where they remain during the juvenile stage (van der Veer et al., 1991; Grioche et al., 1997; Martinho et al., 2008,2013). These important nursery habitats are essential for fish population renewal, being characterized by high food availability and providing refuge against predators and favorable conditions for a rapid growth (Gibson, 1994; Able, 2005; Cabral et al., 2007; Vasconcelos et al., 2011). Polychlorinated dibenzo-p-dioxins (PCDDs), polychlorinated dibenzofurans (PCDFs) and dioxin-like polychlorinated biphenyls (dl-PCBs) are persistent organic pollutants that constitute a risk to wildlife and human health due to their high toxicity and ability to bioaccumulate in biota and biomagnify in food webs (UNEP, 2001; Wan et al., 2005). Since the consumption of fish and fishery products is the main pathway of human exposure to these dioxin- like compounds (EFSA, 2012; Caspersen et al., 2013), the determi- nation of PCDD/Fs and dl-PCBs in fish is important to protect the consumers’ health. Nevertheless, it is also essential to evaluate the risk posed by these contaminants to fish populations. The Euro- pean flounder is particularly exposed to sediment-associated pollu- tants such as PCDD/Fs and dl-PCBs due to their benthic lifestyle and bottom-feeding behavior (Shelepchikov et al., 2008). In addition, early life stages are more susceptible to dioxin-like toxicity com- pared to adult fish (Lanham et al., 2012), requiring considerably lower body burdens to elicit adverse effects (Peterson et al., 1993; Lanham et al., 2012). Growth retardation, cutaneous hemorrhage, craniofacial malformations, histopathologic lesions in several tis- sues or lethality have been described in early life stages of different fish species exposed to 2,3,7,8-tetrachlorodibenzo-p-dioxin (Henry http://dx.doi.org/10.1016/j.marpolbul.2014.05.042 0025-326X/Ó 2014 Elsevier Ltd. All rights reserved. ⇑ Corresponding author at: CFE – Centre for Functional Ecology, Department of Life Sciences, University of Coimbra, Apartado 3046, 3001-401 Coimbra, Portugal. Tel.: +351 239855760x348. E-mail address: mnc@ci.uc.pt (M. Nunes). Marine Pollution Bulletin xxx (2014) xxx–xxx Contents lists available at ScienceDirect Marine Pollution Bulletin journal homepage: www.elsevier.com/locate/marpolbul Please cite this article in press as: Nunes, M., et al. Early contamination of European flounder (Platichthys flesus) by PCDD/Fs and dioxin-like PCBs in Euro- pean waters. Mar. Pollut. Bull. (2014), http://dx.doi.org/10.1016/j.marpolbul.2014.05.042