TA4 Integrating Sublethal Responses and Ecologically Relevant Endpoints
204 Oregon Ballroom
8:00 AM - 12:00 PM, Tuesday
() Integrating and Interpreting Integrators of Sublethal Exposures to Environmental Estrogens.
Lehr, R1, Swackhamer, D1, Simcik, M1, Adams, A1, Erb, J2, Ankley, G3, Denslow, N4, 1 University of Minnesota, Minneapolis, MN, USA2 Three Fold Sensors, Ann Arbor, MI, USA3 US Environmental Protection Agency - MED, Duluth, MN, USA4 University of Florida, Gainesville, FL, USA
ABSTRACT- We are developing an indicator of exposure to environmental estrogens (EE) that will be used to assess exposures to fish communities in coastal systems. The ability to detect the exposures and effects of EEs is often done with biomarker analysis, such as measuring the yolk precursor protein, vitellogenin (vtg), in adult male fish. This is easy in laboratory animals, but poses challenges in the field due to the large numbers of animals needed and the need for collecting a consistent species across sites. We have compared the use of two biosensors that measure the kinetics of binding to the estrogen receptor and to the estrogen response element. These biosensors were then used to assess the estrogenicity of coastal waters in 28 sites across the entire US Great Lakes nearshore region. The results of the biosensor assessments were compared to the chemical analyses of water and sediments from these sites for a suite of estrogenic compounds including hormones and alkyl phenols and ethoxylates, and the trace amounts of chemicals found did not explain the observed estrogenicity. The difference in response of the estrogen receptor and the estrogen response element between sites suggests that different chemicals are eliciting a response initiated at different places within the response pathway. These results underscore the importance of endpoint selection when monitoring EE exposure and suggest that linkage between EE exposure and effect may be highly dependent upon both the chemical constituents of the exposure and the mechanism of action.
Key words: great lakes, environmental estrogens, ecological indicators