title: Determining the effects of a mixture of an endocrine disrupting compound, 17α-ethinylestradiol, and ammonia on fathead minnow (Pimephales promelas) reproduction.
abstract: Aquatic organisms are exposed to a multitude of contaminants and to fully understand the impact of multiple stressors on fish populations, we must first understand the mechanism of action for each toxicant and how the combined effects manifest at the level of the individual. 17α-ethinylestradiol (EE2) has been known to cause adverse reproductive effects including reduced fecundity and fertility, intersex and skewed sex ratios in fish by mimicking naturally produced estrogen at low concentrations. Ammonia can cause adverse reproductive and mortality effects in individual fish through effects or damage to the central nervous system. Both EE2 and ammonia are found in most municipal effluents in various concentrations. A flow-through diluter system was used to test the individual effects of these two contaminants at their respective no observable adverse effect concentration (NOAEC) as well as their combined effects on fathead minnow, (Pimephales promelas) reproduction in a mixture exposure. While neither contaminant nor their mixture altered reproduction in terms of fecundity, their mixture resulted in significant fathead minnow mortality during a 21 d exposure. This study demonstrated the need to consider mixture effects when assessing risk for toxicity testing with multiple stressors.
authors.affiliation: Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources, East Lansing, MI 48824, United States.
authors.forename: Brandon M
authors.initials: BM
authors.lastname: Armstrong
authors.affiliation: U.S. Environmental Protection Agency, National Exposure Research Laboratory, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, United States. Electronic address: lazorchak.jim@epa.gov.
authors.forename: James M
authors.initials: JM
authors.lastname: Lazorchak
authors.affiliation: Department of Fisheries and Wildlife, Michigan State University, 13 Natural Resources, East Lansing, MI 48824, United States; Lyman Briggs College, Michigan State University, Holmes Hall, East Lansing, MI 48824, United States.
authors.forename: Cheryl A
authors.initials: CA
authors.lastname: Murphy
authors.affiliation: The McConnell Group c/o U.S. Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, United States.
authors.forename: Herman J
authors.initials: HJ
authors.lastname: Haring
authors.affiliation: U.S. Environmental Protection Agency, Office of Research and Development, National Health and Environmental Effects Research Laboratory, Mid-Continent Ecology Division, 6201 Congdon Blvd, Duluth, MN 55804, United States.
authors.forename: Kathleen M
authors.initials: KM
authors.lastname: Jensen
authors.affiliation: The McConnell Group c/o U.S. Environmental Protection Agency, 26 W. Martin Luther King Dr., Cincinnati, OH 45268, United States.
authors.forename: Mark E
authors.initials: ME
authors.lastname: Smith
mesh_terms: D000641:Ammonia / Q000032:analysis / Q000633:toxicity*; D000818:Animals; D003530:Cyprinidae / Q000254:growth & development* / Q000502:physiology; D052244:Endocrine Disruptors / Q000032:analysis / Q000633:toxicity*; D004997:Ethinyl Estradiol / Q000032:analysis / Q000633:toxicity*; D005260:Female; D008297:Male; D012098:Reproduction / Q000187:drug effects*; D012744:Sex Ratio; D018675:Toxicity Tests; D014819:Vitellogenins / Q000378:metabolism; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
chemical_list: D052244:Endocrine Disruptors; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D004997:Ethinyl Estradiol; D000641:Ammonia
keywords: Ammonia; Ethinylestradiol; Fecundity; Mixture; Mortality; Promelas