Assessing the Sensitivity of Different Life Stages for Sexual Disruption in Roach (Rutilus rutilus) Exposed to Effluents from Wastewater Treatment Works

Surveys of U.K. rivers have shown a high incidence of sexual disruption in populations of wild roach (Rutilus rutilus) living downstream from wastewater treatment works (WwTW), and the degree of intersex (gonads containing both male and female structural characteristics) has been correlated with the concentration of effluent in those rivers. In this study, we investigated feminized responses to two estrogenic WwTWs in roach exposed for periods during life stages of germ cell division (early life and the postspawning period). Roach were exposed as embryos from fertilization up to 300 days posthatch (dph; to include the period of gonadal sex differentiation) or as postspawning adult males, and including fish that had received previous estrogen exposure, for either 60 or 120 days when the annual event of germ cell proliferation occurs. Both effluents induced vitellogenin synthesis in both life stages studied, and the magnitude of the vitellogenic responses paralleled the effluent content of steroid estrogens. Feminization of the reproductive ducts occurred in male fish in a concentration-dependent manner when the exposure occurred during early life, but we found no effects on the reproductive ducts in adult males. Depuration studies (maintenance of fish in clean water after exposure to WwTW effluent) confirmed that the feminization of the reproductive duct was permanent. We found no evidence of ovotestis development in fish that had no previous estrogen exposure for any of the treatments. In wild adult roach that had previously received exposure to estrogen and were intersex, the degree of intersex increased during the study period, but this was not related to the immediate effluent exposure, suggesting a previously determined programming of ovotestis formation

Health effects in fish of long-term exposure to effluents from wastewater treatment works

The effects of simple mixtures of chemicals, with similar mechanisms of action, can be predicted using the concentration addition model (CA). The ability of this model to predict the estrogenic effects of more complex mixtures such as effluent discharges, however, has yet to be established. Effluents from 43 U.K. wastewater treatment works were analyzed for the presence of the principal estrogenic chemical contaminants, estradiol, estrone, ethinylestradiol, and nonylphenol. The measured concentrations were used to predict the estrogenic activity of each effluent, employing the model of CA, based on the relative potencies of the individual chemicals in an in vitro recombinant yeast estrogen screen (rYES) and a short-term (14-day) in vivo rainbow trout vitellogenin induction assay. Based on the measured concentrations of the four chemicals in the effluents and their relative potencies in each assay, the calculated in vitro and in vivo responses compared well and ranged between 3.5 and 87 ng/L of estradiol equivalents (E2 EQ) for the different effluents. In the rYES, however, the measured E2 EQ concentrations in the effluents ranged between 0.65 and 43 ng E2 EQ/L, and they varied against those predicted by the CA model. Deviations in the estimation of the estrogenic potency of the effluents by the CA model, compared with the measured responses in the rYES, are likely to have resulted from inaccuracies associated with the measurement of the chemicals in the extracts derived from the complex effluents. Such deviations could also result as a consequence of interactions between chemicals present in the extracts that disrupted the activation of the estrogen response elements in the rYES. E2 EQ concentrations derived from the vitellogenic response in fathead minnows exposed to a series of effluent dilutions were highly comparable with the E2 EQ concentrations derived from assessments of the estrogenic potency of these dilutions in the rYES. Together these data support the use of bioassays for determining the estrogenic potency of WwTW effluents, and they highlight the associated problems for modeling approaches that are reliant on measured concentrations of estrogenic chemicals

Assessing the Sensitivity of Different Life Stages for Sexual Disruption in Roach () Exposed to Effluents from Wastewater Treatment Works-2

<p><b>Copyright information:</b></p><p>Taken from "Assessing the Sensitivity of Different Life Stages for Sexual Disruption in Roach () Exposed to Effluents from Wastewater Treatment Works"</p><p>Environmental Health Perspectives 2005;113(10):1299-1307.</p><p>Published online 14 Jun 2005</p><p>PMCID:PMC1281270.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Assessing the Sensitivity of Different Life Stages for Sexual Disruption in Roach () Exposed to Effluents from Wastewater Treatment Works-4

<p><b>Copyright information:</b></p><p>Taken from "Assessing the Sensitivity of Different Life Stages for Sexual Disruption in Roach () Exposed to Effluents from Wastewater Treatment Works"</p><p>Environmental Health Perspectives 2005;113(10):1299-1307.</p><p>Published online 14 Jun 2005</p><p>PMCID:PMC1281270.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI.</p

Health Effects in Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works-2

<p><b>Copyright information:</b></p><p>Taken from "Health Effects in Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works"</p><p></p><p>Environmental Health Perspectives 2005;114(S-1):81-89.</p><p>Published online 21 Oct 2005</p><p>PMCID:PMC1874182.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI</p

Lowest observed effect concentrations (LOEC) for different forms of developmental toxicity

<p><b>Copyright information:</b></p><p>Taken from "Health Effects in Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works"</p><p></p><p>Environmental Health Perspectives 2005;114(S-1):81-89.</p><p>Published online 21 Oct 2005</p><p>PMCID:PMC1874182.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI</p

Health Effects in Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works-4

<p><b>Copyright information:</b></p><p>Taken from "Health Effects in Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works"</p><p></p><p>Environmental Health Perspectives 2005;114(S-1):81-89.</p><p>Published online 21 Oct 2005</p><p>PMCID:PMC1874182.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI</p

Health Effects in Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works-1

<p><b>Copyright information:</b></p><p>Taken from "Health Effects in Fish of Long-Term Exposure to Effluents from Wastewater Treatment Works"</p><p></p><p>Environmental Health Perspectives 2005;114(S-1):81-89.</p><p>Published online 21 Oct 2005</p><p>PMCID:PMC1874182.</p><p>This is an Open Access article: verbatim copying and redistribution of this article are permitted in all media for any purpose, provided this notice is preserved along with the article's original DOI</p