La surveillance de la qualité du milieu marin : l'expérience du Réseau National d'Observation (RNO) et le développement de biomarqueurs

Monitoring of marine environment quality can be based on chemical analysis of contaminants in the major components of the environment: seawater, sediment, biota. The respective interest of these different matrices is discussed and the fundamentals for the use of bivalves in the international Mussel Watch are presented. The objectives of the French RNO are 1) to assess the levels and trends of contaminants; 2) to assess the biological effects of contaminants. Analysis of the chemicals in biota is an indispensable complement to the biological approach, allowing their bioavailable fraction to be quantified. However, only a fraction of xenobiotics incorporated in living beings is biologically active and can exert a noxious effect on the biota. In addition, biological markers allow the assessment of the impact of pollutants at different levels of biological organization. Some of them are now considered as classical: their use in the field is in a validation phase and they are the object of quality control procedures based on their quantification (Erod, MT, Ache, etc.). However, the development of new biological markers ranging over different levels of biological organization is also needed.