Identification of Estrogenic Chemicals in STW Effluent. 2. In Vivo Responses in Trout and Roach

Abstract

The occurrence of certain natural and synthetic steroidal estrogens in the final effluent from STW has been demonstrated. 17β-Estradiol and estrone were present at concentrations in the tens of nanograms per liter range, and the synthetic estrogen 17R-ethynylestradiol was also identified, albeit in the low nanogram per liter range. The findings from subsequent in vivo tank trial experiments, in which adult male rainbow trout (Oncorhynchus mykiss) and adult roach (Rutilus rutilus) were exposed for 21 days via the water to environmentally relevant concentrations of 17β-estradiol and estrone are presented. In addition, the response of adult male and female roach following exposure to 17β-estradiol (1, 10, and 100 ng/L) was compared to the response to the alkylphenolic xenoestrogen, 4-tert-octylphenol (1, 10 and 100 µg/L). Plasma levels of vitellogenin were determined using previously validated radioimmunoassays in order to measure the estrogenic response of the fish to the varying concentrations of the compounds tested. The results indicate that environmentally relevant concentrations of natural steroidal estrogens are sufficient to account for the levels of vitellogenin synthesis observed in caged male fish placed downstream of certain STW effluent discharges in British rivers.

Effect-directed analysis (EDA) in aquatic ecotoxicology: state of the art and future challenges

“…By means of bioassay-directed fractionation using estrogen-sensitive systems such as MVLN or MCF7-luc cells, it could be demonstrated that the concentrations of the endogenous estrogen 17β-estradiol and the synthetic estrogen ethinylestradiol represented between 88% and 99.5% of the total estrogen equivalents in water samples from certain areas (Snyder et al 2001). However, other studies revealed that synthetic chemicals such as alkylphenolic compounds can account for the majority of the estrogenic potential of a sample (Hollert et al 2005;Khim et al 1999b;Routledge et al 1998;Sheahan et al 2002). One of the key challenges for the assessment of the contribution of individual chemicals to the bioassay derived estrogenic potential (estradiol equivalents=EEQs) of a sample is the sensitivity of the utilized analytical method, as has been demonstrated by a study assessing estrogenic compounds in complex environmental samples in the catchment area of the River Neckar, Germany (Hollert et al 2005).…”

Occurrence of endocrine-disrupting chemicals in riverine sediments from the Pearl River Delta, China

“…EDCs consist of a wide range of natural and man-made chemicals, most of which are released to natural waters by anthropogenic activities and whose adverse effects on normal reproductive functions of aquatic species have widely been confirmed (Jobling et al, 1996;Routledge et al, 1998;Oehlmann, 2000;Irwin et al, 2001;Levy et al, 2004). For instance, widespread estrogenic chemical input has been regarded as an important factor related to the decline of fish abundance in freshwater systems (Jobling et al, 1998;Burkhardt-Holm et al, 2005;Kidd et al, 2007).…”

Modeling the dispersion of endocrine disruptors in the Santos Estuarine System (Sao Paulo State, Brazil)

“…The estimated EE2 concentrations were between 0.06 and 0.25 ng L -1 , which is within the toxic range of 0.1 -100 ng L -1 , levels which are harmful to some species of aquatic organisms (PAWLOWSKI et al, 2004;FOLMAR et al, 2000;RODGRES-GRAY et al, 2000;ROUTLEDGE et al, 1998). These results suggest that estrogens are unlikely to cause adverse effects on the biota in the SES environment, since the concentrations of estrogens in surface waters were generally found to be below toxic thresholds.…”

“…The amounts of estrogen identified in effluents are enough to induce vitellogenin synthesis (VTG), changes in gonads, impaired reproduction, and increased offspring mortality in aquatic organisms (PAWLOWSKI et al, 2004;FOLMAR et al, 2000;RODGRES-GRAY et al, 2000;ROUTLEDGE et al, 1998).…”