Treatment of 17-Ethinylestradiol (EE2) in Water Using UV/H₂O₂ and Reverse Osmosis (RO) Membranes: Assessment of Estrogenic Activity and Membrane Adsorption

17 alpha-Ethinylestradiol (EE2) is a synthetic hormone, which has a high estrogenic potential, and it is usually discharged into the environment through sewage and industrial effluents. Low concentrations of EE2, and H2O2, which are not so common in the studies, were applied in removing process of micropollutants. Photodegradation and removal of EE2 from water were investigated using two treatment processes, UV/H2O2 and reverse osmosis (RO), respectively. Furthermore, changes in estrogenic activity using in vitro yeast estrogen screen assay, as well as the adsorption of EE2 by membrane (TW30-4040, polyamide) surface, were evaluated. All experiments showed that the concentration of H2O2 is a very important variable that influences the degradation of EE2 in all UV doses evaluated. Moreover, they showed estrogenic activity at the end of the treatment due to the amount of EE2 remaining after each experiment. The membrane rejection efficiency varied from 90 to 98% and the adsorption experiments with EE2 initial concentration of 1000 mu g.L-1 resulted in 11 mg.m(-2) membrane surface adsorption. The RO membrane showed higher EE2 removal efficiency through size exclusion and adsorption than the UV/H2O2 process under the evaluated conditions.