title: Exposure of three generations of the estuarine sheepshead minnow (Cyprinodon variegatus) to the androgen, 17beta-trenbolone: effects on survival, development, and reproduction.
abstract: Estimating long-term effects of endocrine-disrupting chemicals on a species is important to assessing the overall risk to the populations. The present study reports the results of a 42-week exposure of estuarine sheepshead minnows (Cyprinodon variegatus) to the androgen, 17beta-trenbolone (Tb) conducted to determine if partial-(F0) or single-generation (F1) fish exposures identify multigenerational (F0-F3) effects of androgens on fish. Adult F0 fish were exposed to 0.007, 0.027, 0.13, 0.87,and 4.1 microg Tb/L, the F1 generation to < or =0.87 microg Tb/L, the F2 fish to < or =0.13 microg Tb/L, and the F3 fish to < or =0.027 microg Tb/L. The highest concentrations with reproducing populations at the end of the F0, F1, and F2 generations were 4.1, 0.87, and 0.027 microg Tb/L, respectively. Reproduction in the F0, F1, and F2 generations was significantly reduced at 0.87, 0.027, and 0.027 microg Tb/L, respectively. Fish were significantly masculinized in the F1 generation exposed to 0.13 microg Tb/L or greater. Female plasma vitellogenin was significantly reduced in F0 fish exposed to > or =0.87 microg Tb/L. Gonadosomatic indices of the F0 and F1 generations were significantly increased at 0.87 and 0.13 microg Tb/L in the F0 and F1 generation, respectively, and were accompanied by ovarian histological changes. Reproduction was the most consistently sensitive measure of androgen effects and, after a life-cycle exposure, the daily reproductive rate predicted concentrations affecting successive generations. The present study provides evidence that a multiple generation exposure of fish to some endocrine-disrupting chemicals can result in developmental and reproductive changes that have a much greater impact on the success of a species than was indicated from shorter term exposures.
authors.affiliation: U.S. Environmental Protection Agency, National Health and Environmental Effects Research Laboratory, Gulf Ecology Division, 1 Sabine Island Drive, Gulf Breeze, Florida 32561, USA.
authors.forename: Geraldine M
authors.initials: GM
authors.lastname: Cripe
authors.forename: Becky L
authors.initials: BL
authors.lastname: Hemmer
authors.forename: Sandy
authors.initials: S
authors.lastname: Raimondo
authors.forename: Larry R
authors.initials: LR
authors.lastname: Goodman
authors.forename: Dannielle H
authors.initials: DH
authors.lastname: Kulaw
mesh_terms: D000728:Androgens / Q000633:toxicity*; D000818:Animals; D012734:Disorders of Sex Development / Q000097:blood / Q000139:chemically induced / Q000662:veterinary; D052244:Endocrine Disruptors / Q000633:toxicity*; D005260:Female; D005618:Fresh Water / Q000737:chemistry; D006066:Gonads / Q000187:drug effects / Q000473:pathology; D007695:Killifishes / Q000254:growth & development / Q000378:metabolism / Q000502:physiology*; D008297:Male; D010063:Ovum / Q000187:drug effects; D012098:Reproduction / Q000187:drug effects*; D012623:Seawater / Q000737:chemistry; D016019:Survival Analysis; D014204:Trenbolone Acetate / Q000633:toxicity*; D014819:Vitellogenins / Q000097:blood; D014874:Water Pollutants, Chemical / Q000633:toxicity
chemical_list: D000728:Androgens; D052244:Endocrine Disruptors; D014819:Vitellogenins; D014874:Water Pollutants, Chemical; D014204:Trenbolone Acetate