The seven year itch—progress in research on endocrine disruption in aquatic invertebrates since 1999

Abstract

Since the issue of endocrine disrupting chemicals (EDCs) emerged, research efforts were mainly devoted to (1) vertebrate systems, and (2) estrogenic substances. In ecotoxicology, terrestrial wildlife populations (e.g. puma) were investigated, while in the aquatic environment fish and amphibians were in focus. That invertebrates, which constitute the major part of our animal biodiversity, were largely ignored in the equation (except maybe for the effects of tributyltin on marine molluscs), encouraged scientists on both sides of the ocean to bundle their efforts and organise a workshop to explore the status quo on invertebrate endocrinology. Finally, the workshop ENDOCRINE DISRUPTION IN INVERTEBRATES: ENDOCRINOLOGY, TESTING AND ASSESSMENT (EDIETA) was held in The Netherlands in 1998. This highly successful workshop culminated in the SETAC publication carrying the same title as the workshop (deFur et al. 1999). Since its publication this book has become a reference work for researchers, lecturers, students and regulators that were involved in the various aspects of invertebrate endocrinology, from basic research to the regulatory implications of endocrine disruptor testing. Moreover, since the book provided many suggestions for improvement and indicated gaps in our knowledge, it also served as a starting point for further research. It was our impression that in the past 7 years a great effort has been undertaken to fill these data gaps and to improve our understanding of invertebrate endocrinology. While this knowledge has been brought into use for aquatic invertebrates, relatively little progress has been made in understanding endocrine disruption in terrestrial invertebrates (although a springtail reproduction test has been initiated at the OECD level). This may be related to issues with terrestrial exposures, which are harder to define than for aquatic invertebrates, which experience an aqueous whole body exposure. For example, the influence of a sewage effluent (including residues of the potent estrogen 17aethinylestradiol) is easily measurable in aquatic ecosystems, while it is hard to measure the influence of sewage sludge application on terrestrial ecosystems. This is due to (1) complicating matrix effects in the chemical analysis, (2) considerable heterogeneity of the soil, (3) the mitigating effect of soil due to its high adsorptive capacity and (4) the lack of established terrestrial bioassays for endocrine disruptors. From the start our focus has been on Endocrine disruption in aquatic invertebrates, a topic on which we organised and chaired a session at the Annual meeting of SETAC-Europe in Lille, France in May 2005. There we started thinking about the compilation of a special issue on this subject. That our initiative succeeded is not only due to the possibility that SETAC gave us to organise the aforementioned session, but also to the editors of Ecotoxicology who gave us the editorial time and space to compile this work. Furthermore, it was particularly encouraging that virtually all authors we L. Weltje (&) Agricultural Center, Ecotoxicology, BASF Aktiengesellschaft, Carl-Bosch-Strasse 64, D-67117 Limburgerhof, Germany e-mail: lennart.weltje@basf.com