TY - JOUR
T1 - Factors Affecting Behavior of Phenolic Endocrine Disruptors, Estrone and Estradiol, in Constructed Wetlands for Domestic Sewage Treatment
AU - Dai, Yu Nv
AU - Dan, A.
AU - Yang, Yang
AU - Tam, Nora Fung Yee
AU - Tai, Yi Ping
AU - Tang, Xiao Yan
N1 - Publisher Copyright:
© 2016 American Chemical Society.
PY - 2016/11/1
Y1 - 2016/11/1
N2 - This study investigated the efficiency of 12 pilot-scale constructed wetlands (CWs) with different configurations on the removal of estrone and estradiol from raw domestic sewage. An orthogonal design was employed to evaluate the impact of four principal design parameters of CWs, including four wetland types, three substrates, three plant conditions, and three hydraulic loading rates, in summer and winter. A bench-scale anoxic simulation test was performed in the laboratory to clarify the photolysis, sorption, and degradation of estrogens. Estrogens were more effectively removed by the 12 CWs during summer. The experiment showed that target estrogens were efficiently removed by wetland substrate under anoxic conditions through exothermic sorption and degradation even in winter. This suggests that the inefficient removal in CWs in winter likely resulted from subsequent cleavage of a considerable amount of estrogen conjugates in influent due to insufficient decomposition at low temperatures. The transformation from estradiol to estrone could be driven by residual microbial activities not inhibited by azide, and the reversible process was then driven by active microorganisms but not solely abiotic redox reactions. Among the four design parameters, wetland-type was the most important and downward-vertical flow CWs performed best.
AB - This study investigated the efficiency of 12 pilot-scale constructed wetlands (CWs) with different configurations on the removal of estrone and estradiol from raw domestic sewage. An orthogonal design was employed to evaluate the impact of four principal design parameters of CWs, including four wetland types, three substrates, three plant conditions, and three hydraulic loading rates, in summer and winter. A bench-scale anoxic simulation test was performed in the laboratory to clarify the photolysis, sorption, and degradation of estrogens. Estrogens were more effectively removed by the 12 CWs during summer. The experiment showed that target estrogens were efficiently removed by wetland substrate under anoxic conditions through exothermic sorption and degradation even in winter. This suggests that the inefficient removal in CWs in winter likely resulted from subsequent cleavage of a considerable amount of estrogen conjugates in influent due to insufficient decomposition at low temperatures. The transformation from estradiol to estrone could be driven by residual microbial activities not inhibited by azide, and the reversible process was then driven by active microorganisms but not solely abiotic redox reactions. Among the four design parameters, wetland-type was the most important and downward-vertical flow CWs performed best.
UR - http://www.scopus.com/inward/record.url?scp=84993993625&partnerID=8YFLogxK
U2 - 10.1021/acs.est.6b02026
DO - 10.1021/acs.est.6b02026
M3 - Article
C2 - 27723316
AN - SCOPUS:84993993625
SN - 0013-936X
VL - 50
SP - 11844
EP - 11852
JO - Environmental Science and Technology
JF - Environmental Science and Technology
IS - 21
ER -