Abstract：
So far, little has been known about how the combined collection systems of sewage and rainfall runoff (CCSs) affect emerging contaminants in river water. To fill up the knowledge gap, this study was conducted to investigate the spatial distributions of three natural estrogens (NEs, i.e., estrone (E1), 17β-estradiol (E2) and estriol (E3)) and their conjugates (C-NEs) in the Pearl River in the wet and dry seasons. Results showed that the respective average concentrations of NEs and C-NEs at different locations alongside the Pearl River in the wet season were 7.3 and 1.8 times those in the dry season. Based on estrogen equivalence (EEQ), the average estimated EEQ level in the Pearl River waters in the wet season was nearly 10 times that in the dry season. These seemed to imply that the CCSs in the wet season not only cause untreated sewage into the receiving water body, but greatly decrease the removal efficiency of NEs and C-NEs in wastewater treatment plant. Furthermore, the estimated annual loads of E1, E2, and E3 to the Pearl River in the wet season accounted for about 88.6 %, 100 %, and 99.3 % of the total annual loads. Consequently, this work for the first time demonstrated that the CCSs in cities with high precipitation are unfavorable for controlling of emerging contaminants.
摘要：
到目前为止,关于污水和降雨径流（CCS）的组合收集系统如何影响河水中出现的污染物，人们知之甚少。为了填补知识空白，这项研究是为了调查三种天然雌激素(NEs，即，雌酮（E1），17β-雌二醇（E2）和雌三醇（E3））及其结合物（C-NEs）在干湿季节的珠江。结果表明，在雨季，珠江沿岸不同位置的NEs和C-NEs的平均浓度分别是旱季的7.3和1.8倍。基于雌激素等效性(EEQ)，在雨季，珠江水域的平均估计EEQ水平是旱季的近10倍。这些似乎暗示，雨季的CCS不仅导致未经处理的污水进入接收水体，但是大大降低了污水处理厂中NE和C-NE的去除效率。此外，珠江雨季E1,E2,E3年负荷估计约占88.6%,100%,年总荷载的99.3%。因此,这项工作首次表明，高降水城市的CCS不利于控制新兴污染物。
