Résumé
In the context of the deployment of Offshore Renewable Energy farms in France and worldwide, the potential impact of cathodic protections (CP) was highlighted as an environmental concern. Based on this issue, the ECOCAP project aimed at performing a conclusive chemical risk assessment for elements released by CP in the marine water column. One of such CP is galvanic anode cathodic protection system (GACP) which relies on the degradation of an anode mainly composed of aluminium (Al ~95%) and zinc (~5%), released in the environment during functioning. The purpose of this study was to evaluate toxicity of GACP to fish. A GACP system was settled in a tank filled with 43 L of marine water and an electric current (I = 0.1 A) was applied for 24 h. The solution was further decanted for 24 h to eliminate the particle phase and the final stock solution was used to prepare dilutions for toxicity assessment. For comparison, we produced in parallel an equivalent AlCl3, 6 H2O solution by dissolving 4.5 g of salt into 43 L of seawater. Embryo-larval (OECD 212) and chronic exposure over 4 months were performed using marine medaka (Oryzias melastigma).