Water Resources Research Act Program

Details for Project ID 2007MA74B

Development of a standardized protocol for fish bioassays detecting estrogenic exposure

Institute: Massachusetts
Year Established: 2007 Start Date: 2007-03-01 End Date: 2008-02-29
Total Federal Funds: $4,917 Total Non-Federal Funds: $37,984

Principal Investigators: Kathleen Arcaro, Lauren Moffatt

Project Summary: Endocrine disrupting compounds are of increasing concern in waterways throughout the Northeast. Specifically, estrogenic contaminants have been detected downstream of agricultural operations, industrial discharges, and even municipal wastewater treatment facilities. Concern regarding the feminization of fish and wildlife species has led to the demand for sensitive, accurate, and reliable means to detect estrogenic activity in water samples. Fish models are ideal bioassays for examining potentially polluted waterways because fish are directly exposed to, and quickly concentrate aquatic contaminants. In concert with the use of molecular techniques, specifically the analysis of changes in gene expression, fish bioassays can be a sensitive indicator of estrogenic pollution. However, studies using fish bioassays have reported variable results with respect to assay sensitivity and robustness of response. Part of the variability among results is due to differences in experimental setup, exposure conditions, and endpoints measured. I propose to optimize the protocol for detecting estrogenic compounds in water samples using male Japanese medaka (Oryzias latipes). Male medaka will be exposed to the endogenous hormone 17β-Estradiol and assay parameters including length of exposure, number of fish per tank, volume of water per tank and number of water changes will be systematically examined. I will then use quantitative real-time RT-PCR to quantify changes in a panel of estrogen-responsive genes in each of the experimental groups. Results form this study will help establish a standard operating procedure for detecting estrogenic compounds using medaka, and provide a guideline for optimizing other fish bioassays.