Abstract |
A whole-lake endocrine disruption experiment was conducted by Fisheries and Oceans Canada at the Experimental Lakes Area (ELA) in northwestern Ontario for three years beginning in 2001. This experiment examined population, organismal, biochemical and cellular-level effects in lake trout, white sucker, fathead minnow, and pearl dace exposed to environmentally-relevant (4-6 ng/L) concentrations of the synthetic estrogen, 17alpha-ethynylestradiol. The USEPA collaborated in this study by evaluating vitellogenin (vtg) gene expression in: (1) indigenous fathead minnows and pearl dace collected from the dosed and reference lakes in 2001 through 2003, before and after dosing; (2) indigenous minnows collected in 2001from the reference lake and deployed for 1, 3, 7 and 13 days in the dosed and reference lakes; and (3) Cincinnati cultured minnows exposed to water collected in 2001 through 2004 from ELA lakes and shipped to Cincinnati. RT-PCR methods were used to measure vtg expression. |