In vitro agonistic and antagonistic endocrine disrupting effects of organic extracts from waste water of different treatment processes

Abstract

Effluents from wastewater treatment plant (WWTP) have been reported to have a broad spectrum of endocrine disrupting compounds (EDCs). The majority of studies have focused on the occurrence of estrogenic activity, while ignoring nuclear hormone receptors (NRs) pathways. In the present study, a battery of in vitro yeast bioassays and a cell bioassay, including antagonistic and agonistic effects on estrogen receptor (ER), androgen receptor (AR), progesterone receptor (PR), estrogen-related receptor (ERR) and aryl hydrocarbon receptor (AHR), were conducted to evaluate the removal efficiencies of EDCs by different treatment processes of a WWTP located in Beijing. Estrogenic, anti-estrogenic, anti-androgenic, anti-progesteronic, anti-ERR and the activation of AHR activities were detected in samples from all treatment processes and the receiving water. The concentration of estrogenic contaminants with estradiol (E-2) equivalent concentrations ranged from 0.82 x 10(-9) to 3.54 x 10(-9)g E-2-EQ center dot L-1. The concentration of anti-estrogenic contaminants with 4-hydroxytamoxifen (4-OHT) equivalent concentrations ranged from 1.24 x 10(-6) to 2.36 x 10(-6) g 4-OHT-EQ center dot L-1. The concentration of anti-androgenic contaminants ranged from 2.21 x 10(-8) to 3.52 x 10(-6) g flutamide-EQ center dot L-1. The concentration of anti-progesteronic contaminants ranged from 3.15 x 10(-5) to 2.71 x 10(-4) g RU486-EQ center dot L-1. The concentration of anti-ERR contaminants ranged from 7.09 x 10(-5) to 6.50 x 10(-4) g 4-OHT-EQ center dot L-1. The concentration of AHR activators ranged from 1.7 x 10(-10) to 3.4 x 10(-10) g TCDD-EQ center dot L-1. These processes including secondary clarifier, coagulation, as well as coal and sand filtration could eliminated 67.2% of estrogenic contaminants, 47.0% of anti-estrogenic contaminants, 98.3% of anti-androgenic contaminants, 88.4% of anti-progesteronic contaminants, 65.4% of anti-ERR contaminants and 46.9% of AHR activators. WWTP effluents contain multiple receptor disruptors may have very complex adverse effects on exposed organisms.