| 摘要: | 一般家庭污水中皆可發現環境賀爾蒙物質（environmental hormones, EHs）的蹤跡，再加上其未能被傳統污水處理廠有效去除而存在於放流水中。故，本研究之目的旨在探討不同處理設備之人工濕地系統（constructed wetland systems）去除家庭污水中雌激素活性的能力。本研究選用青魚將魚（Oryzias latipes, Japanese medaka）為指標生物，並採用更替型靜水（static-renewal）式連續暴露五天後，探討不同處理系統間之進流水及放流水的雌激素活性。實驗過程中，以西方點墨法（western blotting）量測雄性青將成魚體內肝臟中卵黃蛋白前質（vitellogenin, VTG）含量、肝臟體重比指數（hepatosomatic index, HSI）與生殖腺體重比指數（gonadosomatic index, GSI），來瞭解污水中仿雌激素物質對魚類生殖的影響。本研究並利用酵素免疫吸附分析法（enzyme-linked immunosorbent assay, ELISA）檢測污水中非離子介面活性劑－烷基苯酚聚乙氧基醇（alkylphenol ethoxylates or polyoxyethylene alkylphenyl ether, APE）含量，以確認造成魚體內卵黃蛋白前質誘導之物質。本研究結果顯示：（1）雄性青將成魚是相當適合直接作為反應污水中雌激素活性之指標生物。例如，二行社區的家庭污水含高濃度的仿雌激素化學物質，可促使雄魚體內VTG被誘發。其經濕地處理後的放流水，雌激素活性可被大幅的降低；（2）不同處理設備之人工濕地系統對於家庭污水中雌激素活性的降解能力各有差異；（3）短暴露時間是未能引發暴露於不同來源水樣的魚體內兩組織（肝臟及生殖腺指數）在重量上的明顯改變；（4）以活性污泥法為二級處理設施之污水處理廠，對於污水中之雌激素活性具有一些程度的降解能力；（5）以ELISA所檢測出之人工濕地系統和污水處理廠中APE濃度是偏低的，因此，APE可能並非是導致暴露於進流水中的青將魚體內VTG誘導之主要化合物。
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. |
