Estrogen mediated effects in the Sydney rock oyster, Saccostrea glomerata, following field exposures to sewage effluent containing estrogenic compounds and activity

► Evidence of estrogenicity of sewage effluent in terms of individual compounds (via GCMS) and EEQ (via YES® assay). ► Development of novel real-time PCR assay for measurement of vitellogenin in S. glomerata. ► Demonstrated relationships between field exposures to sewage effluent and reproductive effects in an invertebrate model. ► Field exposures of S. glomerata to estrogenic effluent increased vitellogenin protein, female proportions and female gonadal development. The Sydney rock oyster, Saccostrea glomerata, has been demonstrated as a useful biomonitor of estrogenic compounds following laboratory exposures, yet its utility in the assessment of estrogenic exposure and effects under field conditions requires investigation. To achieve this aim, S. glomerata were deployed in Newcastle, Australia in the effluent receiving marine waters of Burwood Beach WWTP (Burwood Beach “near”,