Metal contamination of Posidonia oceanica meadows along the Corsican coastline (Mediterranean) C. Lafabrie * , C. Pergent-Martini, G. Pergent University of Corsica, Faculty of Sciences, Equipe Ecosyste `mes Littoraux, BP 52, 20250 Corte, France Received 8 August 2006; received in revised form 22 January 2007; accepted 26 January 2007 The seagrass Posidonia oceanica is a relevant tracer of spatial metal contamination and an interesting tool for water quality evaluation. Abstract The aim of this study is to determine metal (Cd, Co, Cr, Hg, Ni, Pb) concentrations in Posidonia oceanica tissues along the Corsican coast- line. The results show that except for Cr, all the metals are preferentially accumulated in the blades; this is particularly interesting as it means that future metal analyses may be carried out only on the blades avoiding thus the removal of the shoots. Moreover, they show that metal con- centrations may reflect the ‘‘background noise’’ of the Mediterranean Sea. Station 15 (Canari) can however be distinguished from the others due to its high Co, Cr and Ni concentrations. This result may be related to the presence of a previous asbestos mine, located near this station. There- fore, this study reinforces the usefulness and the relevance of Posidonia oceanica as a tracer of spatial metal contamination and as an interesting tool for water quality evaluation. Ó 2007 Elsevier Ltd. All rights reserved. Keywords: Trace metals; Seagrass; Corsica; Posidonia oceanica; Asbestos mine; Mediterranean 1. Introduction The major sources of pollution of surface waters include ef- fluent discharges by industries, atmospheric depositions of pol- lutants and occasional accidental spills of toxic chemicals (Ikem and Egiebor, 2005). Trace metals are regarded as serious pollutants of the aquatic environment because of their toxicity, their persistence, their difficult biodegradability and their ten- dency to concentrate in aquatic organisms (Ikem and Egiebor, 2005; Schu ¨u ¨rmann and Markert, 1998). They enter the marine environment through atmospheric and land-based effluent sources (Islam and Tanaka, 2004). There is currently a great interest in the use of living organ- isms as pollution biomonitors in aquatic ecosystems (Andersen et al., 1996; Demirezen and Aksoy, 2006; Goldberg, 1986; Morillo et al., 2005; Pergent-Martini and Pergent, 2000; Usero et al., 2005) given that the method used previouslydchemical analysis of waterddoes not provide sufficient information on the bioavailability of metals present in the environment (Morillo et al., 2005). In the Mediterranean sea, the endemic seagrass Posidonia oceanica (L.) Delile has been used as a metal bioindicator for several decades (Campanella et al., 2001; Capiomont et al., 2000; Catsiki and Panayotidis, 1993; Costantini et al., 1991; Malea et al., 1994; Maserti et al., 1988; Pergent-Martini, 1998; Sanchiz et al., 1990; Schlacher- Hoenlinger and Schlacher, 1998; Warnau et al., 1995, 1996). The Corsican island is subject to few sources of contami- nants that are of anthropic origin (low population density on its coasts: <60 inhabitants/km 2 ; IFEN, 2000; and, low indus- trialization rate; INSEE, 1999) and it is therefore usually con- sidered a pristine region with healthy widespread Posidonia oceanica meadows (Pasqualini et al., 1998). However, only lit- tle quantitative data is available on the general pollution of the * Corresponding author. Tel.: þ33 495 450 075; fax: þ33 495 462 441. E-mail address: lafabrie@univ-corse.fr (C. Lafabrie). 0269-7491/$ - see front matter Ó 2007 Elsevier Ltd. All rights reserved. doi:10.1016/j.envpol.2007.01.047 Available online at www.sciencedirect.com Environmental Pollution 151 (2008) 262e268 www.elsevier.com/locate/envpol