Effets de pollutions par hydrocarbures sur les capacités de défense d'organismes marins

The effects of PAHs, considered among the most toxic by the United States Environmental Protection Agency, were tested in vitro and in vivo on two commercial species of the Pertuis-Charentais (Charente-Maritime, France): sea bass, Dicentrarchus labrax, and the Pacific oyster, Crassostrea gigas. This study was carried out as part of the European project EROCIPS with the aim of finding new immunological biomarkers caused by occasional pollution by hydrocarbons. During in vitro experimentation, pollutants and immunological biomarkers were choosen. Thereafter, the in vitro exposures to the soluble fraction of Erika's heavy fuel oil and its fluxant, light cycle oil, began. These exposures enable the validation of the experimental system used, with, in particular, the measurement of bioaccumulated PAHs and metabolites and of choice of the immune biomarkers. The phenoloxidase activity of molluscs and the haemolytic activity of the alternative complement pathway of fish were proposed, for the first time, as suitable biomarkers for the evaluation of pollutant risks in field conditions.