Biomonitoraggio dei corsi d’acqua superficiali del Lodigiano attraverso saggi multispecie

Maria Rosa Lovati*°, Elisa Di Gioia*, Silvia Castiglioni*°, Corrado L. Galli°, Università degli Studi di Milano, *Lab. Tossicologia Ambientale, via S. Francesco 13-26900 Lodi, °Dip. di Scienze Farmacologiche, via Balzaretti 9-20133 Milano

To evaluate the water and sediment quality of surface watercourses and sediments of Lombardia in the Lodi area, a biological approach with ecotoxicological assays was performed in collaboration with "Provincia di Lodi" and "ARPA Lombardia", Department of Lodi. Since the biological tests can provide sensitive indications of potential synergism between the different pollutants present in the surface water/sediment, the results obtained in this study together with the chemical/physical data can provide an overview of the real environment conditions of the rivers tested. A battery of tests with species belonging to different trophic levels, such as bioluminescent bacteria (Vibrio fischeri), crustaceans (Daphnia magna, Heterocypris incongruens), green algae (Pseudokirchneriella subcapitata), seeds of plants (Lepidium sativum, Cucumis sativus and Sorghum saccharatum), was used to evaluate the quality of both water and sediment samples coming from rivers and canals in the Lodi area. The data obtained in the present study showed a multiple situation in which, cases of marked toxicity (Lambro, Lisone, Tormo rivers), are followed by good (Muzza canal) or quite-good conditions (Po, Adda rivers); the Vibrio fisheri assay revealed for Lambro and Lisone sediments high pollution situations. These data suggest that the sediment surface layer removing might be a suitable approach to improve the watercourse and the biotic component quality.