Introduction: The Ecological Relevance of Chemically Induced Endocrine Disruption in Wildlife

7 Monograph Over the last two decades, there has been increasing scientific concern and public debate regarding the adverse effects of chemical pollutants in the environment that can interfere with the normal functioning of the endocrine system in wildlife and in humans (the so-called endocrine-disrupting chemicals, EDCs). These concerns have been fueled primarily by reports of disrupted reproductive function and development in certain wildlife—mammals, birds, fish, amphibians, and mollusks—and by the increased incidence of certain diseases of the endocrine system in humans. Investigators hypothesize that EDCs are the cause. Some of the adverse effects observed in wildlife species are strongly associated with exposure to chemicals that mimic or interfere with hormone function, particularly estrogen function, but in many cases, the causal link between exposure to EDCs and endocrine disruption is unclear. Because of the diverse effects of EDCs on the thyroid, retinoid, androgen, estro-gen, and corticosteroid systems of a wide range of animals, it is imperative that research continues to address the extent of the risk posed by EDCs to wildlife. The ecological relevance of endocrine disruption in wildlife is, however, difficult to quantify, as there is limited understanding of how physiological changes affect the individual animal and how individual responses affect population and community. Furthermore, a major challenge faced by environmental biologists is the need to place endocrine disruption into context with other environmental pressures faced by our wildlife populations, for example, global warming. In July 2004 an international workshop was convened at the University of Exeter in the United Kingdom to provide a forum for the dissemination and discussion of the most recent data on the ecological relevance of chemical-induced endocrine disruption in wildlife. The workshop was organized by the COMPRENDO Project (Comparative Research on Endocrine Disruption; COMPRENDO 2006). COMPRENDO is one of four projects [COMPRENDO, EDEN (Endocrine Disrupters: Exploring Novel Endpoints, Exposure, Low-Dose and Mixture-Effects in Humans, Aquatic Wildlife and Laboratory Animals), EURISKED (Multi-organic Risk Assessment of Selected Endocrine Disrupters), FIRE (Risk Assessment of Brominated Flame Retardants As Suspected Endocrine Disrupters for Human and Wildlife Health)] that form the research laboratory core (comprising 60 laboratories) of the CREDO (Coordinating European Environmental and Human Research into Endocrine Disruption) cluster for research, technological development, and demonstration activities in the European Community (CREDO 2006). CREDO is funded by the European Commission's Fifth Framework Programme. One hundred-eighty delegates attended the meeting from 20 countries spanning Europe, the United States, Japan, India, …