Evaluation of Chemical Contamination in the Western Mediterranean Using Mussel Transplants

Abstract

The MYTILOS project aimed to draw up a baseline report on chemical contamination of coastal seas on a Western Mediterranean scale. On the basis of the methodology developed on the French Mediterranean coast by Ifremer and the Agence de l'Eau Rhone Mediterranee & Corse (Rhone, Mediterranean & Corsica water board) since 1996 with the RINBIO monitoring program, data were collected between 2004 and 2006 along the northern and southern continental coasts and around the Balearic Islands, Sicily, Sardinia, and Corsica. MYTILOS was supported by the INTTERREG III B/MEDOC program, steered by Ifremer, and backed by Toulon Var Technologies, in cooperation with research institutions from concerned countries: ICRAM (Italy), IEO (Spain), PSTS (Sicily), IMEDEA (Balearic Islands), CSIC, Agencia Catalana de l'Aigua (Spain), INSTM (Tunisia), ISMAL (Algeria), INRH and University of Agadir (Morocco). MYTTLOS formed part of the MEDICIS program and was also backed by the PNUE/PAM - MEDPOL and Rhone Mediterranee & Corse water board. Three cruises (2004, 2005, 2006), for a total of 120 days at sea, were carried out to install mussel bags for 3 months at 123 stations and to recover them. The results obtained for 40 chemical compounds in the western Mediterranean show similarities with observations previously made on the French coast in terms of the highest measured levels and background level. The most highly impacted areas are mainly urban and industrial centers and the outlets of major rivers. A far higher dilution is seen for organic compounds than for heavy metals when going from the coast towards open sea. Metal levels measured in the open sea were often found to be similar to those in natural shellfish populations living along the coast.