This data set describes experiments that were conducted to investigate whether exposure of male fathead minnows to environmentally-relevant estrone concentrations would result in elevated plasma 17β-estradiol concentrations in the fish. Secondly, we sought to establish whether observed elevations in plasma 17β-estradiol occurred as a result of the conversion of external estrone by the fish using an approach involving exposure of the fish to 13C-labeled estrone. Endpoints reported in the dataset include plasma 17β-estradiol and estrone concentrations, plasma vitellogenin concentrations, hepatic vitellogenin mRNA, 13C-labeled plasma 17β-estradiol and estrone concentrations, and testicular and/or hepatic expression of aromatase and several hydroxysteroid dehydrogenases involved in estrone metabolism. This dataset is associated with the following publication: Ankley, G., D. Feifarek, B. Blackwell, J. Cavallin, K. Jensen, M. Kahl, S. Poole, E. Randolph, T. Saari, and D. Villeneuve. Reevaluating the significance of estrone as an environmental estrogen (article). ENVIRONMENTAL SCIENCE & TECHNOLOGY. American Chemical Society, Washington, DC, USA, 51: 4705-4713, (2017).

Adult fathead minnows were exposed to dilutions of a historically estrogenic wastewater treatment plant effluent in a 21-d reproduction study. This dataset is comprised of a variety of endpoints representing key events along adverse outcome pathways linking estrogen receptor activation and other molecular initiating events to reproductive impairment. This study demonstrates the value of using an integrative approach that encompasses analytical chemistry, in vitro bioassays, and in vivo apical and pathway-based approaches with endpoints spanning from molecular- (e.g., gene expression) to organismal- (e.g., reproduction) levels of biological organization to help infer causal relationships between chemistry and potential effects on reproduction. This dataset is associated with the following publication: Cavallin , J., K. Jensen , M. Kahl , D. Villeneuve , K. Lee, A. Schroeder , J. Mayasich, E. Eid, K. Nelson, R. Milsk, B. Blackwell, J. Berninger , C. LaLone, C. Blanksma, T. Jicha , C. Elonen , R. Johnson , and G. Ankley. Pathway-based approaches for assessment of real-time exposure to an estrogenic wastewater treatment plant effluent on fathead minnow reproduction. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 35(3): 702-716, (2016).

Adult fathead minnows were exposed to dilutions of a historically estrogenic wastewater treatment plant effluent in a 21-d reproduction study. This dataset is comprised of a variety of endpoints representing key events along adverse outcome pathways linking estrogen receptor activation and other molecular initiating events to reproductive impairment. This study demonstrates the value of using an integrative approach that encompasses analytical chemistry, in vitro bioassays, and in vivo apical and pathway-based approaches with endpoints spanning from molecular- (e.g., gene expression) to organismal- (e.g., reproduction) levels of biological organization to help infer causal relationships between chemistry and potential effects on reproduction. This dataset is associated with the following publication: Cavallin , J., K. Jensen , M. Kahl , D. Villeneuve , K. Lee, A. Schroeder , J. Mayasich, E. Eid, K. Nelson, R. Milsk, B. Blackwell, J. Berninger , C. LaLone, C. Blanksma, T. Jicha , C. Elonen , R. Johnson , and G. Ankley. Pathway-based approaches for assessment of real-time exposure to an estrogenic wastewater treatment plant effluent on fathead minnow reproduction. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 35(3): 702-716, (2016).

Data set includes empirical results from 60 h, 10 d, and 21 d exposures of female fathead minnows to the fungicide imazalil as well as simulations from predictive models anchored to an established adverse outcome pathway (https://aopwiki.org/aops/25). Contents are organized into multiple tabs: (1) Simulated effects on plasma 17b-estradiol and vitellogenin used to inform experimental design. (2) Model simulations based on nominal concentrations used in the 60 h, 10 d, and 21 d exposures. (3) Biological effects data from the 60 h experiment. (4) Analytical exposure verification from the 60 h experiment. (5) Biological effects data from the 10 d exposure. (6) Biological effects data from 21 d exposure. (7) Analytical exposure verification from the 10 d and 21 d exposures. (8) Reproduction data from the 10 d and 21 d exposures. (9) Simulated reproduction results based on nominal exposure concentrations used in the 10 d and 21 d exposures. (10) Histopathology evaluations for selected females from the 10 d and 21 d exposures. This dataset is associated with the following publication: Villeneuve, D., B. Blackwell, C. Blanksma, J. Cavallin, W. Cheng, R. Conolly, K. Conrow, D. Feifarek, L. Heinis, K. Jensen, M. Kahl, R. Milsk, S. Poole, E. Randolph, T. Saari, K. Watanabe, and G. Ankley. Case Study in 21st-Century Ecotoxicology: Using In Vitro Aromatase Inhibition Data to Predict Reproductive Outcomes in Fish In Vivo. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 42(1): 100-116, (2023).

Data set includes empirical results from 60 h, 10 d, and 21 d exposures of female fathead minnows to the fungicide imazalil as well as simulations from predictive models anchored to an established adverse outcome pathway (https://aopwiki.org/aops/25). Contents are organized into multiple tabs: (1) Simulated effects on plasma 17b-estradiol and vitellogenin used to inform experimental design. (2) Model simulations based on nominal concentrations used in the 60 h, 10 d, and 21 d exposures. (3) Biological effects data from the 60 h experiment. (4) Analytical exposure verification from the 60 h experiment. (5) Biological effects data from the 10 d exposure. (6) Biological effects data from 21 d exposure. (7) Analytical exposure verification from the 10 d and 21 d exposures. (8) Reproduction data from the 10 d and 21 d exposures. (9) Simulated reproduction results based on nominal exposure concentrations used in the 10 d and 21 d exposures. (10) Histopathology evaluations for selected females from the 10 d and 21 d exposures. This dataset is associated with the following publication: Villeneuve, D., B. Blackwell, C. Blanksma, J. Cavallin, W. Cheng, R. Conolly, K. Conrow, D. Feifarek, L. Heinis, K. Jensen, M. Kahl, R. Milsk, S. Poole, E. Randolph, T. Saari, K. Watanabe, and G. Ankley. Case Study in 21st-Century Ecotoxicology: Using In Vitro Aromatase Inhibition Data to Predict Reproductive Outcomes in Fish In Vivo. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 42(1): 100-116, (2023).

"Morshead ML, Jensen KM, Ankley GT, Vliet S, LaLone CA, Aller AV, Watanabe KH, Villeneuve DL. Putative adverse outcome pathway development based on physiological responses of female fathead minnows to model estrogen versus androgen receptor agonists. Aquat Toxicol. 2023 Aug;261:106607. doi: 10.1016/j.aquatox.2023.106607. Epub 2023 Jun 9. PMID: 37354817.". This dataset is associated with the following publication: Morshead, M., K. Jensen, G. Ankley, S. Vliet, C. LaLone, D. Villeneuve, A. Vidales Aller, and K. Watanabe. Putative adverse outcome pathway development based on physiological responses of female fathead minnows to model estrogen versus androgen receptor agonists. AQUATIC TOXICOLOGY. Elsevier Science Ltd, New York, NY, USA, 261: 106607, (2023).

Feminization of male fish and the role of endocrine-active chemicals in this phenomenon has been an area of intense study for many years. Estrone (E1), a natural steroid, is found in aquatic environments sometimes at relatively high concentrations. However, E1 has been less thoroughly studied than 17β-estradiol (E2) or 17α-ethynylestradiol due in part to a relatively lower potency in metabolically-limited estrogen receptor (ER) binding/activation assays. Recent evidence suggests that in vivo biotransformation of E1 to E2 may occur in fathead minnows (Pimephales promelas) residing in environments with high concentrations of E1, such as near wastewater treatment plants. The enzymes likely responsible for this biotransformation, 17β-hydroxysteroid dehydrogenases (17βHSDs), have been well characterized in mammals but to a lesser extent in fish species. In the current study, a novel systematic analysis of amino acid sequence data from the National Center for Biotechnology Information database demonstrated that multiple 17βHSD isoforms are conserved across different fish species. Experimentally, we showed that metabolically-active hepatic cytosolic preparations from two commercially important salmonid species, rainbow trout and lake trout, biotransformed E1 to E2 to a degree sufficient to alter results of competitive ER binding assays. These results from in silico and in vitro analyses indicate E1 and biotransformation may play a significant role in the feminization of a variety of fish species in contaminated aquatic environments. This dataset is associated with the following publication: Tapper, M., R. Kolanczyk, C. LaLone, J. Denny, and G. Ankley. Conversion of estrone to 17â-Estradiol: A potential confounding factor in assessing risks of environmental estrogens to fish. ENVIRONMENTAL TOXICOLOGY AND CHEMISTRY. Society of Environmental Toxicology and Chemistry, Pensacola, FL, USA, 39(10): 2028–2040, (2020).

Physiological endpoints observed in adult largemouth bass in response to an EE2 (17 alpha-ethinylestradiol) or mixture of estrone and atrazine exposure under laboratory pond conditions. Also included are water quality and chemical concentration data. Adult LMB were exposed in outdoor pond mesocosms from post-spawning to early gonad recrudescence to either EE2 (2.4 nanograms per liter), or a mixture of endocrine-active substances commonly detected in the Chesapeake Bay watershed, atrazine (5.4 micrograms per liter) and estrone (47.9 nanograms per liter). Male reproductive condition, sperm count, and sperm motility were assessed.

Alternative complement pathway assay data observed in adult largemouth bass plasma in response to an EE2 (17alpha-ethinylestradiol) or mixture of estrone and atrazine exposure under laboratory pond conditions, with associated fish identification information.

Aromatase inhibition is one of the chemical modes of action of concern to EPA's Endocrine Disruptor Screening Program (EDSP). In vitro bioassays that can detect aromatase inhibition are part of both the EDSP tier 1 screening program and are included subset of ToxCast assays employed for EDSP21 screening. An adverse outcome pathway (AOP) linking aromatase inhibition to reproductive dysfunction in fish has been described and endorsed by the OECD, establishing a scientifically sound connection between aromatase inhibition and adverse apical outcomes relevant to risk assessment and regulatory decision-making. Further, computational models that allow for quantitative prediction of dose-response time-course behaviors and the potential severity of the adverse outcome based on in vitro screening data have been developed. The present study provides further weight of evidence to support this AOP and its use in regulatory decision-making. In particular, it identifies rapid responses to aromatase inhibition that can be expected to occur within the first 24 h of exposure, examines the dynamic stability of gene expression responses over that period to help identify appropriate time periods in which characteristic gene expression responses may serve as effective biomarkers of exposure to aromatase inhibitors, and provides insights into different gene regulatory mechanisms that may be operating over the first few hours of exposure versus more systemic endocrine-related regulation that appear to take over after 6-12 h of exposure. These data continue to refine our understanding of this important mode of endocrine disruption and how to more efficiently and effectively both model and test for it to support regulatory decision-making. This dataset is associated with the following publication: Schroeder, A., G. Ankley, T. Habib, N. Garcia-Reyero, B. Escalon, K. Jensen, M. Kahl, E. Durhan, E. Makynen, J. Cavallin, D. Martinovic-Weigelt, E. Perkins, and D. Villeneuve. Rapid effects of the aromatase inhibitor fadrozole on steroid production and gene expression in the ovary of female fathead minnows (Pimephales promelas). GENERAL AND COMPARATIVE ENDOCRINOLOGY. Academic Press Incorporated, Orlando, FL, USA, 252: 79-87, (2017).