Assessment and monitoring of water quality of the gulf of Morbihan, a littoral ecosystem under high anthropic pressure

• Published in: Marine Pollution Bulletin
• Main Authors: Le Grand, A., Maxime, V., Kedzierski, M., Duval, H., Douzenel, P., Sire, O., Le Tilly, V.
• Other Authors: Université de Bretagne Sud (UBS), Institut de Recherche Dupuy de Lôme (IRDL), École Nationale d'Ingénieurs de Brest (ENIB)-Université de Bretagne Sud (UBS)-Université de Brest (UBO)-École Nationale Supérieure de Techniques Avancées Bretagne (ENSTA Bretagne)-Centre National de la Recherche Scientifique (CNRS), ASPEET grant from the Universite Bretagne Sud, SERPBIO foundation, city of Locmariaquer, AQUASTER grant from Region Bretagne
• Format: Article in Journal/Newspaper
• Language: English
• Published: HAL CCSD 2017
• Subjects: Littoral water monitoring; Enzyme response index; Estrogenic endocrine disrupters; Crassostrea gigas; Gulf of Morbihan; [SPI]Engineering Sciences [physics]
• Online Access: https://hal.science/hal-01697241; https://doi.org/10.1016/j.marpolbul.2017.07.003

International audience This field study is intended to propose a global methodology to assess and monitor the water quality of the gulf of Morbihan, a littoral ecosystem under increasing anthropic pressure. To this end, the Locmariaquer site, where Crassostrea gigas is extensively cultivated, was selected to perform a one-year follow-up of tissular glutathione S-transferase and acetylcholinesterase specific activities in this filter feeder organism. Calculation of an integrated index, corresponding to the ratio of the two enzymes activities, allowed to discriminate from the environmental noise, several clusters which could be representative environmental stress, potentially latent pollution. Moreover, the estrogenic activity was assessed in water samples collected at Locmariaquer and other strategic sites of the gulf. The results evidenced a low estrogenic-disrupting compound contamination of waters. Overall, this methodology produced an accurate outlook of a basal state for the gulf and could be developed in the context of a chronic monitoring of this site.