Occurrence and removal of steroidal estrogens in Centre Eastern Tunisia municipal sewage treatment plant

Occurrence and removal efficiencies of both natural estrogens, estrone (E1), 17β-estradiol (E2) and estriol (E3), and a synthetic estrogen, 17α-ethinylestradiol (EE2), were investigated in sewage treatment plant in Centre Eastern Tunisia employing simple activated sludge process. Concentrations of target estrogens were determined in both wastewater and sludge phases by gas chromatography coupled with mass spectrometer. Among the estrogens studied, E3 was found as the dominant compound detected in wastewater samples with average concentration up to 300 ± 4 ng/L in influent and up to 36 ± 2 in effluent. High aqueous phase removals (>85%) were achieved for E3, while only low to moderate removals for E1, E2, and EE2 (<75%). Based on the mass balance analysis, sorption onto sludge played a dominant role in the removal of estrogens in warm season, especially for E1 and E2 (69.5 and 66.3%, respectively), while biological degradation played a significant role in hot season (61%). © 2013 Balaban Desalination Publications. All rights reserved

Fate of selected estrogenic hormones in an urban sewage treatment plant in Tunisia (North Africa)

© 2014 Elsevier B.V. Estrogenic compounds have been monitored for one year at an urban sewage treatment plant (STP) located in Tunisia, to evaluate their fate and seasonal variations. The concentrations of these compounds were determined in both wastewater and sludge phases by gas chromatography coupled with mass spectrometry (GC-MS). Results showed that the highest removal of all estrogens (≥. 80%) was observed in summer. Mass balance analysis revealed that biodegradation was the predominant removal mechanism. Moreover, the results showed that the removal efficiency of the studied emerging micropollutants and their concentrations in the solid phase of return sludge were much higher in winter and spring than in summer and autumn. These findings were closely related to microbial activity and the concentration of mixed liquor suspended solids (MLSSs). Finally, the findings can be used to help with the modifications that could be implemented in that STP for the improved removal of estrogenic contaminants