Determination of Estrogenicity in Effluents from Different Constructed Wetland Systems

• Main Authors: Jen-Hsien Liang, 梁任賢
• Other Authors: Chien-Min Chen
• Format: Others
• Language: zh-TW
• Published: 2005
• Online Access: http://ndltd.ncl.edu.tw/handle/10977050232095031968

碩士 === 嘉南藥理科技大學 === 環境工程與科學系碩士班 === 93 === Environmental hormones (EHs) have been detected in domestic wastewater. Some EHs could not be removed by sewage treatment plants (STPs), thus are present in effluents. The objective of this study was to investigate the removal of estrogenicity of wastewater by different constructed wetland systems. Japanese medaka was chosen as a biological indicator in the present study. A static-renewal system with a 5-day exposure was applied to determine the estrogenicity of influent and effluent samples collected from systems studied. Estrogenic responses were identified based on expression of liver vitellogenin (VTG) in Japanese medaka using western blotting. Gonadosomatic index (GSI) and hepatosomatic index (HSI) were also measured to observe hepatic and reproductive effects on male adult fish by wastewater. Furthermore, an enzyme-linked immunosorbent assay (ELISA) kit was used for analyzing alkylphenol ethoxylatec (APE) in wastewater. The major findings in this study are as followed. 1. male medaka is suitable for serving as a bio-indicator for determination of estrogenicity in wastewater. The domestic wastewater collected from the Er-hang could induce VTG in fish, but after treated with a constructed system, a substantially removal of estrogenicity was observed in its effluent. 2. due to characteristics variation of different constructed wetland systems, the removal abilities of different systems for estrogenicity are different. 3. because of short exposure period, no obvious physiological alteration, in term of weight changes (hepatosomatic and gonadosomatic indices), was observed in fish treated with various samples. 4. a STP, using activated sludge as the secondary treatment process, could remove some estrogenicity in wastewater. 5. APE concentrations detected by ELISA in some wastewater samples collected from constructed wetland systems and STPs were very low, and may not be fully responsible for the VTG induction observed in fish resulted from exposure to influent samples.