TOXICITY, GENOTOXICITY AND ESTROGENIC ACTIVITY OF THE PHARMACEUTICAL RESIDUES IN THE AQUATIC ENVIRONMENT

In the last years pharmaceuticals have aroused great interest as environmental pollutants for their toxic effects towards non target organisms. This study wants to give attention not only to the overall ecotoxicity of drugs on non target organisms but also to a further adverse effect of drugs, the endocrine interference. The most representative drugs of the widespread classes in environment were investigated as well as their possible photoderivatives, obtained by solar simulator irradiation in water. The photoproducts were identified by their physical features. Bioassays were performed on rotifers and microcrustaceans to assess acute and chronic toxicity, while SOS Chromotest and Ames test were utilized to detect the genotoxic potential of the investigated compounds. The YES-test and the E-screen assay were performed to detect the capability of these substances to bind the human estrogenic receptor  (hER in comparison with 17-estradiol. The results showed that the parent compounds did not show any acute toxicity at the highest concentration tested (100 mg/L) for all the organisms utilized in the bioassays. Chronic exposure to these compounds caused inhibition of growth population on rotifers and crustaceans. Genotoxic and mutagenic effects were frequently found for photoproducts suggesting that transformation products, as already reported, may show effects higher than the respective parental compound. Out of several tested pharmaceuticals, some were positive to YES-assay and/or E-screen assay; in particular, Furosemide and the fibrates (Bezafibrate, Fenofibrate and Gemfibrozil) gave the maximal estrogenic response. Tamoxifen showed its dual activity as agonist and antagonist of hER.