R3 AM Ecotoxicogenomics of Emerging Chemical Issues
Thursday, 17 November 2005: 8:00 AM - 11:40 AM in Ballroom 3

(TOT-1117-807767) Application of genomic and proteomic indicators to characterize exposure of aquatic organisms to environmental contaminants.

Toth, G¹, Knoebl, I¹, Biales, A¹, Lattier, D¹, Bencic, D¹, Lazorchak, J¹, ¹ US Environmental Protection Agency, National Exposure Research Laboratory, Cincinnati, OH, USA

ABSTRACT- Advances in molecular biological methods are continually being brought to bear on human health research, from a basic understanding of systems biology to identification of toxicity pathways for environmental stressors and to correlations of molecular indicators with physiological outcomes in human epidemiology studies. This prodigious research effort is beginning to be mirrored for aquatic organisms in the academic, government and private sector research laboratories. The U.S. EPA's National Exposure Research Laboratory (NERL) is partnering with other laboratories within EPA as well as the DOE's Sandia National Laboratories and Joint Genome Institute to develop microarray resources for the fathead minnow. Combined with other gene discovery tools and proteomic analyses, NERL scientists are developing molecular methods to diagnose exposure to chemicals and chemical families, such as endocrine-disrupting chemicals (EDCs), pesticides and pharmaceuticals. These tools will be applied to answer real world questions about the extent and level of exposure to and effects on organisms in aquatic ecosystems. Current applications include analyses of estrogenic activity in a national scale study on wastewater treatment plant effluents, partnership with USGS in studying exposure issues related to the finding of intersex in smallmouth bass in the Potomac watershed and analyses of estrogenic activity in several cyprinids sampled during Environmental Monitoring and Assessment Program (EMAP) studies in the Ohio River watershed. Ultimately, a wide range of molecular indicators will be developed that are phenotypically-anchored to relevant ecological function (e.g., reproduction) and that will allow for characterization of exposure and effects before they are manifested at the tissue, organ, individual, or population level. Data for several projects in which these tools are used to diagnose exposure of aquatic organisms to EDCs in the field will be presented. Although this work was reviewed by EPA and approved for publication, it may not necessarily reflect official Agency policy.

Key words: genomics, proteomics, endocrine disruption, aquatic organisms