Screening of endocrine disrupting compounds using in vitro estrogen receptor transcriptional activation bioassays

Many endocrine disrupting compounds (EDCs) are released from wastewater treatment plant (WWTP) effluents into surface waters worldwide. The objectives of this research were: (1) to explore the use of in vitro estrogen-receptor transcriptional activation (ERTA) assays to screen for estrogenic EDCs in aquatic samples, (2) to investigate WWTPs as a source of EDCs into the aquatic environment, and (3) to examine whether these bioassays can be applied in monitoring estrogenic EDCs in fish. ERTA assay analysis of reference estrogens and WWTP samples, using both mammalian and yeast cell lines had less than 5-fold inter-assay variation compared to β-estradiol equivalent (EEQ) values. WWTP samples had EEQ values consistently higher than 1 ng/L, a concentration that could potentially cause endocrine disruption in fish. ERTA assay analysis of fortified tissue samples correlated with doses; however, the recovery was low (1-3%), and future studies may focus on improving the extraction procedure.