Department of Experimental Pathology, Medical Biotechnology, Infectivology, Epidemiology, University of Pisa, 37 San Zeno Street, 56127 Pisa, Italy

In this work the estrogenic/antiestrogenic activity of coastal marine water samples from five sites of the Northern Mediterranean Sea was assayed using a recombinant Saccharomyces cerevisiae yeast strain (RMY326 ER-ERE) transfected with the human estrogen receptor . Extraction of potential EDCs from seawater was performed in columns packed with XAD-2 resins.

The estrogenic activity was calculated as percentage of the activity of 17β-estradiol (10 nM) and it ranged from 4.8% and 59.03%, significantly depending on sampling site (p = 0.0013) and season (p < 0.05). Antagonistic activity of extracts was also detected and the percentage of inhibition of estradiol-dependent β-galactosidase induction ranged to 52.8%. These results point the reliability of the yeast assay as a first level screening test to assess the quality of aquatic environments.