Seasonal variation in oestrogenic potency and biological effects of wastewater treatment works effluents assessed using ERE-GFP transgenic zebrafish embryo-larvae

Effluents from wastewater treatment works (WwTW) exhibit both temporal and spatial variation in oestrogenicity, however few studies have attempted to quantify how this affects biological responses fish. Here we used an oestrogen-responsive green fluorescent protein (ERE-GFP) transgenic zebrafish (Danio rerio) oestrogenic activity health effects for exposure three different WwTW effluents. Endpoints measured included survival/hatching rate, GFP induction (measured target tissues or gfp mRNA whole embryos) vtg embryos. Exposure one of the study effluents (at 100%), resulted some mortality, all 50% 100%) caused decreases hatching rates. Higher levels corresponded with higher steroidal oestrogens effluents, lowest-observed-effect concentrations (LOECs) between 31 ng/L 39 oestradiol equivalents (EEQs). Tissue patterns expression WwTWs reflected known targets other chemicals likely present those (i.e. nonylphenol bisphenolic compounds). was similarly responsive (a well-established biomarker oestrogen exposure). We thus demonstrate ERE-GFP as effective model monitoring potency complex mixtures contained within