Das Projekt "Evaluation of the effects of endocrine active chemicals (EACs) for sensitive aquatic wildlife species with the test organism Potamopyrgus antipodarum (Mollusca)" wird vom Umweltbundesamt gefördert und von Universität Frankfurt am Main, Institut für Ökologie, Evolution und Diversität, Abteilung Aquatische Ökotoxikologie durchgeführt. Recent reports have shown that a number of xenobiotics in the environment are able of interfering with the normal endocrine function in animals and also in humans. Suspected effects of such compounds, often referred to as endocrine disruptors (EDs) or endocrine active chemicals (EACs), in humans include decreased sperm counts, increased cases of breast, testicular and other forms of reproductive cancers, genital abnormalities (e.g. hypospadia, cryptorchidism), premature puberty in females, and increased cases of endometriosis. In contrast to these suspicious cases in humans there is convincing evidence for chemically-induced endocrine disruption from wildlife studies. However, the overwhelming majority of investigations on effects of EACs is laboratory based and focuses on vertebrates while much less has been done in the field to address potential population-level effects. More detailed information about the effects on and mechanisms of action in invertebrates has only been obtained from a few cases although invertebrates represent more than 95Prozent of the known species in the animal kingdom. The limited number of examples for endocrine disruption in invertebrates is partially due to the fact that their hormonal systems are rather poorly understood in comparison with vertebrates. Deleterious endocrine changes following an exposure to certain compounds may therefore easily be missed or simply be unmeasurable at present, even though a number of field investigations and laboratory studies show that endocrine disruption has probably occurred. The example of tributyltin (TBT) compounds and their masculinising effects in more than 150 species of prosobranch molluscs shows that apparently trivial biochemical changes can have drastic effects up to the community level by a final sterilisation of affected females with a consequent demise and local extinction of populations. However, with the exception of TBT in marine prosobranchs, it has never been convincingly shown that EACs are capable to exert such far-reaching effects in field populations and pose a risk for their survival at environmentally relevant concentrations. The objective of the proposed project is: (1) to analyse the degree to which aquatic wildlife in central Europe is exposed to EACs in its natural habitat by assessing the well-defined effects in the test with Potamopyrgus antipodarum and (2) to evaluate the potential role of EACs for population declines of sensitive aquatic wildlife species with the example of prosobranch snails by correlating effect data with results from analyses of the macrozoobenthic community.