Exposure of Juvenile Roach (Rutilus rutilus) to Treated Sewage Effluent Induces Dose-Dependent and Persistent Disruption in Gonadal Duct Development

Abstract

Wild roach (Rutilus rutilus) have been found with intersex gonads in rivers throughout the United Kingdom. The incidence of intersexuality is strongly correlated with discharges of estrogenic treated sewage effluent into those rivers, and this has led to the hypothesis that estrogenic chemicals in effluents are feminizing wild male fish. In this study, early-life stage roach (50 days post hatch, dph) were exposed for 150 days to a graded concentration (0%, 12.5%, 25%, 50%, and 100%) of treated sewage (primarily domestic) effluent to examine the effects of exposure on sexual differentiation and development. Measurement of steroid estrogens and alkylphenolic chemicals in the effluent and a resulting dose-dependent induction of vitellogenin (VTG; a female-specific, estrogen-dependent plasma protein) confirmed that the fish had been exposed and responded to "estrogen" in the effluent. Exposure to treated sewage effluent induced feminization of the reproductive ducts in "male" roach in a dose-dependent manner (in full-strength effluent, 100% of the fish had feminized ducts), indicating that the disruption of the gonad ducts seen in wild roach is the result of exposure to treated sewage effluents during early-life stages. There were no effects of treated sewage effluent exposure on germ cell development; therefore, no oocytes occurred in the testes of the feminized male roach. Subsequent, depuration of the effluent exposed fish in "clean" water for 150 days resulted in a reduction in plasma VTG but no alteration of the feminized ducts, indicating that the effect of the treated sewage effluent on reproductive duct development was permanent. The causality of oocytes in the testes of wild male roach therefore remains to be elucidated.

Multiple molecular effect pathways of an environmental oestrogen in fish

“…The test concentration adopted in this work was within the concentration range found in European effluents (Desbrow et al 1998, Ternes et al 1999, Baronti et al 2000, Rodgers-Gray et al 2001. Duplicate tanks of the same numbers of fish were maintained in dilution water as controls.…”

Degradação de fármacos residuais por processos oxidativos avançados

“…No estudo de Rodgers-Gray et al, 41 peixes jovens da espécie Ru� tilus rutilus foram expostos a concentrações gradativas de efluente de ETE por 150 dias contendo além de outros perturbadores endócrinos, estrogênios sintéticos. Os resultados mostraram que a exposição induziu à feminização de peixes machos.…”

Aryl hydrocarbon receptor (AhR) inducers and estrogen receptor (ER) activities in surface sediments of Three Gorges Reservoir, China evaluated with in vitro cell bioassays

“…A combination of in vitro assays with different endpoints and bio-analytical methods is recommended to execute a comprehensive ecotoxicological hazard assessment (Ahlf and Heise 2005;den Besten et al 2003;Jacobs et al 2013). A toxicological endpoint of high importance in the environment involves the estrogen receptor (ER)-mediated gene expression activating by chemical pollution, which can cause hormone-dependent diseases and carcinogenic effects (Toppari et al 1996;Andersen et al 2000;Rodgers-Gray et al 2001). One other relevant toxicological endpoint is aryl hydrocarbon receptor (AhR)-mediated activity, which is known to cause hepatotoxicity, teratogenesis, immunotoxicity, and tumorigenesis (DeVito and Birnbaum 1994;Hankinson 1995).…”