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)

17β-estradiol (E2) and 17α-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 μg·(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.