Estrogen-like and dioxine-like contaminants in three mediterranean lagoons : distribution between deployed mussels (Mytilus galloprovinciallis), semi-permeable membrane devices and sediments
Résumé
Coastal lagoons, like Mediterranean lagoons, are particularly complex environments, often subjected to strong human impacts, including industrial and domestic contaminations. The aim of the present work was to evaluate the usefulness of an experimental set-up strategy in order to measure the distribution of organic contaminants in the lagoons and estimate their potential as endocrine disrupters. For this study, man-made cages containing mussels (Mytilus galloprovinciallis), collected from a clean location, were deployed with semi-permeable membrane devices (SPMDs) during 30 days in the Arnel, Mejean and Thau lagoons. Mussels reflect the total exposure (concentrations of dissolved, colloidal, and particulate contaminant in water), whereas SPMDs only sample truly dissolved organic contaminants that may be accessible and available to higher marine organisms. Sediments were collected at the three locations. Chemical analyses of PAHs, PCBs, alkylphenols, E2 and EE2 were done by GC-MS in mussels, SPMDs and sediments and permitted a global assessment of the organic contamination. In vitro bioassays were done additionally to detect estrogen-like and dioxine-like activities and evaluate the potential toxic potency of those complex mixtures. Estrogenic and dioxine-like activities were respectively screened with the stably transfected luciferase reporter cell lines (MELN) and the PLHC-1 cell lines. A condition index ratio (dry flesh/dry shell weight ratio) and goanadal histology were realised on mussels in order to overcome the problem associated with mussel variability and physical condition