title: Performance of vertical up-flow constructed wetlands on swine wastewater containing tetracyclines and tet genes.
abstract: Antibiotics and antibiotic resistance genes (ARGs) pollution in animal feeding farms received more public attention recently. Livestock wastewater contains large quantities of antibiotics and ARGs even after traditional lagoon treatment. In this study, the performance of vertical up-flow constructed wetlands (VUF-CWs) on swine wastewater containing tetracycline compounds (TCs) and tet genes was evaluated based on three aspects, TCs and tet genes removal efficiencies, residual TCs and tet genes in soils and plants, and the effect of TCs accumulation on nutrients removal and tet genes development. High removal efficiencies (69.0-99.9%) were achieved for oxytetracycline (OTC), tetracycline (TC) and chlortetracycline (CTC) with or without OTC spiked in the influent additionally. TCs concentrations in surface soils increased at first two sampling periods and then decreased after plants were harvested. Satisfactory nutrients removal efficiencies were also obtained, but TN and NH4-N removal efficiencies were significantly negative correlated with total concentration of TCs (∑TCs) in the soils (p < 0.01). The absolute abundances of all the target genes (tetO, tetM, tetW, tetA, tetX and intI1) were greatly reduced with their log units ranging from 0.26 to 3.3. However, the relative abundances of tetO, tetM and tetX in some effluent samples were significantly higher than those in the influent (p < 0.05). The relative abundances of tet genes except for tetO were significantly correlated with ∑TCs in the soils (p < 0.05). In summary, the proposed VUF-CWs are effective alternative for the removal of TCs and tet genes. But it is of great importance to prevent large accumulation of TCs in the soils.
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China; Ningbo Urban Environment Observation and Research Station, Chinese Academy of Sciences, Ningbo 315800, China.
authors.forename: Xu
authors.initials: X
authors.lastname: Huang
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China. Electronic address: cxliu@iue.ac.cn.
authors.forename: Chaoxiang
authors.initials: C
authors.lastname: Liu
authors.affiliation: Zhejiang Entry-Exit Inspection and Quarantine Bureau, Hangzhou 310016, China.
authors.forename: Ke
authors.initials: K
authors.lastname: Li
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
authors.forename: Jianqiang
authors.initials: J
authors.lastname: Su
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
authors.forename: Gefu
authors.initials: G
authors.lastname: Zhu
authors.affiliation: Key Lab of Urban Environment and Health, Institute of Urban Environment, Chinese Academy of Sciences, Xiamen 361021, China.
authors.forename: Lin
authors.initials: L
authors.lastname: Liu
mesh_terms: D000818:Animals; D012097:Repressor Proteins; D013552:Swine; D013754:Tetracyclines / Q000032:analysis*; D062065:Wastewater; D014874:Water Pollutants, Chemical / Q000032:analysis*; D053833:Wetlands
chemical_list: D012097:Repressor Proteins; D013754:Tetracyclines; D062065:Wastewater; D014874:Water Pollutants, Chemical; C034811:tetracycline resistance-encoding transposon repressor protein
keywords: Antibiotic resistance genes; Swine wastewater; Tetracyclines; Vertical up-flow constructed wetlands