Biodiversity in the lagoon of Venice: effects of biocidal compounds on the survival of benthic filter-feeding organisms, with particular reference to compound ascidians

Biocides in the aquatic environment can negatively influence the fitness of many organisms acting at various levels of their biological cycles, such as fertilisation, embryonic nd larval development, larval settlement, asexual reproduction and adult survival. Thus biocidal compounds such as thoseextensively used in the lagoon of Veniceas components of antifouling paints for the protection of submerged manufacts such as piles, quays and boats, can affect the composition and/or the distribution of animal communities. The lagoon of Venice is a coastalsystem of particular ecological relevance, as it represents the sum of many environmental typologies. In general antifouling compounds from harbour activities and agricultural sources can destructurate biocoenoses. Ascidians are sensitive organisms useful as bioindicators in laboratory assays for toxicity evaluation.