Effects of the antimicrobial contaminant triclocarban, and co-exposure with the androgen 17β-trenbolone, on reproductive function and ovarian transcriptome of the fathead minnow (Pimephales promelas).
Triclocarban (TCC) is an antimicrobial agent routinely detected in surface waters that has been hypothesized to interact with the vertebrate endocrine system. The present study examined the effects of TCC alone and in combination with the model endocrine disruptor 17β-trenbolone (TRB) on fish reproductive function. Adult Pimephales promelas were continuously exposed to either 1 µg TCC/L or 5 µg TCC/L, to 0.5 µg TRB/L, or to a mixture (MIX) of 5 µg TCC/L and 0.5 µg TRB/L for 22 d, and a variety of reproductive and endocrine-related endpoints were examined. Cumulative fecundity was significantly reduced in fathead minnows exposed to TRB, MIX, or 5 µg TCC/L. Exposure to 1 µg TCC/L had no effect on reproduction. In general, both TRB and MIX treatments caused similar physiological effects, evoking significant reductions in female plasma vitellogenin, estradiol, and testosterone, and significant increases in male plasma estradiol. Based on analysis of the ovarian transcriptome, there were potential pathway impacts that were common to both TRB- and TCC-containing treatment groups. In most cases, however, those pathways were more plausibly linked to differences in reproductive status than to androgen-specific functions. Overall, TCC was reproductively toxic to fish at concentrations at or near those that have been measured in surface water. There was little evidence that TCC elicits reproductive toxicity through a specific mode of endocrine or reproductive action, nor that it could augment the androgenic effects of TRB. Nonetheless, the relatively small margin of safety between some measured environmental concentrations and effect concentrations suggests that concern is warranted. Environ Toxicol Chem 2017;36:231-242. Published 2016 Wiley Periodicals Inc. on behalf of SETAC. This article is a US government work and, as such, is in the public domain in the United States of America.
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.
Daniel L
DL
Villeneuve
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.
Kathleen M
KM
Jensen
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.
Jenna E
JE
Cavallin
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.
Elizabeth J
EJ
Durhan
US Army Engineer Research and Development Center, Vicksburg, Mississippi, USA.
Natàlia
N
Garcia-Reyero
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.
Michael D
MD
Kahl
Department of Anatomy and Cell Biology, School of Medicine, University of Minnesota Duluth, Duluth, Minnesota, USA.
Richard L
RL
Leino
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.
Elizabeth A
EA
Makynen
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.|Environmental and Molecular Toxicology, Oregon State University, Corvallis, Oregon, USA.
Leah C
LC
Wehmas
US Army Engineer Research and Development Center, Vicksburg, Mississippi, USA.
Edward J
EJ
Perkins
Mid-Continent Ecology Division, US Environmental Protection Agency, Duluth, Minnesota, USA.
Gerald T
GT
Ankley
D000728:Androgens / Q000032:analysis / Q000633:toxicity*; D000818:Animals; D000890:Anti-Infective Agents / Q000032:analysis / Q000633:toxicity*; D002224:Carbanilides / Q000032:analysis / Q000633:toxicity*; D003530:Cyprinidae / Q000254:growth & development* / Q000502:physiology; D004357:Drug Synergism; D052244:Endocrine Disruptors / Q000032:analysis / Q000633:toxicity*; D004703:Endocrine System / Q000187:drug effects; D004958:Estradiol / Q000097:blood; D005260:Female; D005298:Fertility / Q000187:drug effects; D008297:Male; D010053:Ovary / Q000187:drug effects* / Q000378:metabolism; D012098:Reproduction / Q000187:drug effects; D013739:Testosterone / Q000097:blood; D059467:Transcriptome / Q000187:drug effects*; D014204:Trenbolone Acetate / Q000032:analysis / Q000633:toxicity*; D014874:Water Pollutants, Chemical / Q000032:analysis / Q000633:toxicity*
D000728:Androgens; D000890:Anti-Infective Agents; D002224:Carbanilides; D052244:Endocrine Disruptors; D014874:Water Pollutants, Chemical; D013739:Testosterone; D004958:Estradiol; C009540:triclocarban; D014204:Trenbolone Acetate
Adverse outcome pathway; Contaminants of emerging concern; Endocrine-disrupting compounds; Reproductive toxicity; Toxicity mechanisms