Biodegradation of natural and synthetic estrogens in moving bed bioreactor

Estrogen hormones as a group of endocrine disruptive compounds (EDC) can interfere with endocrine system in humans and animals. The goal of this study was to investigate the elimination rate of Estrone (E1), 17 beta-estradiol (E2) and 17 alpha-ethinyl estradiol (EE2) in Moving Bed Bioreactor (MBBR). These analytes extracted by Dispersive Liquid-Liquid Microextraction (DLLME) technique, followed by derivatization, and detected by GC/MS. Estrogen removal efficiency in MBBR improved at high solid retention times (SRTs), which notion is owing to development of nitrification. Estrogen specific removal rate was between 0.22-1.45 mu g.(g VSS)(-1).d(-1) for natural and synthetic hormones. The adsorption rate was 0.9%-3.2%, 0-1.3%, and 0.7%-5.7% for E1, E2, and EE2, respectively. In addition, the biodegradation rates were more than 95% for these compounds. These results illustrated that in MBBR, the biodegradation and the adsorption to biomass are considered as two significant routes for elimination of estrogenic compounds. As a whole, the deterioration rate of estrogens enhanced by MBBR compared to other biological wastewater treatment processes such as conventional activated sludge. (C) 2017 The Chemical Industry and Engineering Society of China, and Chemical Industry Press. All rights reserved.