The concentration and distribution of nonylphe-nol polyethoxylates(NPEOs represents the mixture,and NPnEO represents the monomer)and its metabolites in the influent and effluent of four municipal sewage treatment plan...The concentration and distribution of nonylphe-nol polyethoxylates(NPEOs represents the mixture,and NPnEO represents the monomer)and its metabolites in the influent and effluent of four municipal sewage treatment plants(STPs)in the north of China were measured.Moreover,the concentration and distribution of the above chemicals in the sludge of two STPs were also determined,and the transfer and fate of NPEOs in the sewage treatment process were discussed primarily by analyzing the distribu-tion of the products in the effluent and the sludge.The results showed that NPEOs and its metabolites existed in all the samples of the influent,effluent,and sludge.NPEOs were degraded in the sewage treatment process with the removal efficiency in the range of 23.38%-77.11%,or an average of 52.86%.However,the large analogs of NPnEO were only degraded to small ones,whose degradation rate was rather slow,and consequently the degradation was not complete.Hence,the concentrations of some small metabolites,such as nonylphenol(NP),nonylphenol monoethoxylate(NP1EO),and nonylphenol diethoxylate(NP2EO)were elevated in the effluent.These small metabolites are more toxic than the large NPnEO analogs,and some of them were reported to exhibit environmental endocrine disrupting activity.From this point of view,the process of sewage treatment does not reduce but elevate the risk of NPEOs,which becomes the main source of these small NPnEO in the environment.The sludge exhibited good adsorption ability for NPEOs,especially for the small analogs,which led to the high level of NPEOs in the sludge.Hence,reasonable disposal of the surplus sludge to avoid re-pollution is very important.展开更多
Nonylphenol ethoxylate (NPEO)-degrading bacteria were isolated from activated sludge using an improved isolation method, and the corresponding degradation behaviours were investigated. Eight NPEO-degrading strains dis...Nonylphenol ethoxylate (NPEO)-degrading bacteria were isolated from activated sludge using an improved isolation method, and the corresponding degradation behaviours were investigated. Eight NPEO-degrading strains distributed in genera Pseudomonas, Sphingomonas, Sphingobium, Cupriavidus, Ralstonia, Achromobacter, and Staphylococcus were acquired. The latter five genera have never been reported for the degradation of NPEOs. Four degradation patterns were observed for the eight pure strains. In pattern A, NPE...展开更多
基金This work was supported by Kurita Water Environ-ment Foundation of Japan(14701)the National Natural Science Foundation of China(Grant No.20277022).
文摘The concentration and distribution of nonylphe-nol polyethoxylates(NPEOs represents the mixture,and NPnEO represents the monomer)and its metabolites in the influent and effluent of four municipal sewage treatment plants(STPs)in the north of China were measured.Moreover,the concentration and distribution of the above chemicals in the sludge of two STPs were also determined,and the transfer and fate of NPEOs in the sewage treatment process were discussed primarily by analyzing the distribu-tion of the products in the effluent and the sludge.The results showed that NPEOs and its metabolites existed in all the samples of the influent,effluent,and sludge.NPEOs were degraded in the sewage treatment process with the removal efficiency in the range of 23.38%-77.11%,or an average of 52.86%.However,the large analogs of NPnEO were only degraded to small ones,whose degradation rate was rather slow,and consequently the degradation was not complete.Hence,the concentrations of some small metabolites,such as nonylphenol(NP),nonylphenol monoethoxylate(NP1EO),and nonylphenol diethoxylate(NP2EO)were elevated in the effluent.These small metabolites are more toxic than the large NPnEO analogs,and some of them were reported to exhibit environmental endocrine disrupting activity.From this point of view,the process of sewage treatment does not reduce but elevate the risk of NPEOs,which becomes the main source of these small NPnEO in the environment.The sludge exhibited good adsorption ability for NPEOs,especially for the small analogs,which led to the high level of NPEOs in the sludge.Hence,reasonable disposal of the surplus sludge to avoid re-pollution is very important.
基金the National Natural Sci-ence Foundation of China (No. 50578153, 50525824)the Ministry of Science and Technology, China (No.2006DFA91870)
文摘Nonylphenol ethoxylate (NPEO)-degrading bacteria were isolated from activated sludge using an improved isolation method, and the corresponding degradation behaviours were investigated. Eight NPEO-degrading strains distributed in genera Pseudomonas, Sphingomonas, Sphingobium, Cupriavidus, Ralstonia, Achromobacter, and Staphylococcus were acquired. The latter five genera have never been reported for the degradation of NPEOs. Four degradation patterns were observed for the eight pure strains. In pattern A, NPE...