M7 PM Metals in the Environment: Aquatic Biological Perspectives
Monday, 14 November 2005: 1:50 PM - 5:30 PM in 327-329

(THE-1118-337607) Monitoring metals: mussels or passive samplers? Developing appropriate solutions to European Water Directive requirements.

Thebault, H¹, Griscom, S^{1, 3}, Desnues, A¹, Gonzalez, J-L², Andral, B², Sauzade, D², Kantin, R², Shine, J³, Senn, D³, Lewis, C³, ¹ Institut de Radioprotection et de Sûreté Nucléaire, La Seyne sur Mer, France³ Harvard School of Public Health, Boston, Ma, USA² Institut français de recherche pour l'exploitation de la mer, La Seyne sur Mer, France

ABSTRACT- Measuring trace metals concentration in marine waters in a way that is ecologically relevant is a difficult goal. New European Framework Water Directives require that, in order to follow progress towards its ambitious objectives: to reach 'good' chemical status for coastal water masses by the year 2015, concentrations of various dissolved 'contaminants of concern' must be measured on a regular basis. The French Mussel-watch program has monitored large-scale, long-term trends in metal, organic, and radioactive contaminants in coastal waters for over 25 years. This program has helped to assess efforts to reduce contaminant input as well as to focus efforts on persistent toxic matter. Unfortunately, tissue-residue data cannot be used to directly measure contaminant concentrations in water, an essential element of the new European Directives for pollution monitoring. A new inexpensive passive equilibrium sampler is presently being tested in the field to determine it's effectiveness in satisfying some of the new Directive requirements. In collaboration with Harvard School of Public Health and IFREMER, IRSN is testing this new sampler (the Gellyfish), which appears promising as an effective tool to measure a bioavailable fraction of trace metals in seawater: the free-ion metal concentration. Three separate field projects have facilitated the testing: 1. MYGELEX (MYtilus GELlyfish Experiment), a one-year field experiment in which monthly metal concentrations are concurrently measured in caged mussels, Gellyfish, dissolved and particulate phases; 2. COMPAS (COMparison of Passive Samplers), a 7 week deployment that compared metal concentrations in Gellyfish and DGT (Diffusive Gradient Thin-film) samplers; and, 3. MYTILOS, a project in which Gellyfish were deployed alongside caged mussels at 30 sites in the island and coastal areas of Spain and Italy. The Gellyfish may provide insight into DOC-complexation with trace metal and unravel uptake routes of metal into marine organisms. Further, the low cost of Gellyfish may allow countries lacking in research funds, the ability to afford monitoring.

Key words: monitoring, trace metals, mussel, passive sampler