title: Removal of antibiotics and antibiotic resistance genes from domestic sewage by constructed wetlands: Effect of flow configuration and plant species.
abstract: This study aims to investigate the removal of antibiotics and antibiotic resistance genes (ARGs) in raw domestic wastewater by various mesocosm-scale constructed wetlands (CWs) with different flow configurations or plant species including the constructed wetland with or without plant. Six mesocosm-scale CWs with three flow types (surface flow, horizontal subsurface flow and vertical subsurface flow) and two plant species (Thaliadealbata Fraser and Iris tectorum Maxim) were set up in the outdoor. 8 antibiotics including erythromycin-H2O (ETM-H2O), monensin (MON), clarithromycin (CTM), leucomycin (LCM), sulfamethoxazole (SMX), trimethoprim (TMP), sulfamethazine (SMZ) and sulfapyridine (SPD) and 12 genes including three sulfonamide resistance genes (sul1, sul2 and sul3), four tetracycline resistance genes (tetG, tetM, tetO and tetX), two macrolide resistance genes (ermB and ermC), two chloramphenicol resistance genes (cmlA and floR) and 16S rRNA (bacteria) were determined in different matrices (water, particle, substrate and plant phases) from the mesocosm-scale systems. The aqueous removal efficiencies of total antibiotics ranged from 75.8 to 98.6%, while those of total ARGs varied between 63.9 and 84.0% by the mesocosm-scale CWs. The presence of plants was beneficial to the removal of pollutants, and the subsurface flow CWs had higher pollutant removal than the surface flow CWs, especially for antibiotics. According to the mass balance analysis, the masses of all detected antibiotics during the operation period were 247,000, 4920-10,600, 0.05-0.41 and 3500-60,000μg in influent, substrate, plant and effluent of the mesocosm-scale CWs. In the CWs, biodegradation, substrate adsorption and plant uptake all played certain roles in reducing the loadings of nutrients, antibiotics and ARGs, but biodegradation was the most important process in the removal of these pollutants.
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Jun
authors.initials: J
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China. Electronic address: guangguo.ying@gmail.com.
authors.forename: Guang-Guo
authors.initials: GG
authors.lastname: Ying
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Xiao-Dong
authors.initials: XD
authors.lastname: Wei
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: You-Sheng
authors.initials: YS
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Shuang-Shuang
authors.initials: SS
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Li-Xin
authors.initials: LX
authors.lastname: Hu
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Liang-Ying
authors.initials: LY
authors.lastname: He
authors.affiliation: Institute of Environmental Health and Pollution Control, School of Environmental Science and Engineering, Guangdong University of Technology, Guangzhou 510006, China.
authors.forename: Zhi-Feng
authors.initials: ZF
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Fan-Rong
authors.initials: FR
authors.lastname: Chen
authors.affiliation: State Key Laboratory of Organic Geochemistry, CAS Research Centre for Pearl River Delta Environment Pollution and Control, Guangzhou Institute of Geochemistry, Chinese Academy of Sciences, Guangzhou 510640, China.
authors.forename: Yong-Qiang
authors.initials: YQ
authors.lastname: Yang
mesh_terms: D000900:Anti-Bacterial Agents / Q000032:analysis*; D001673:Biodegradation, Environmental; D002681:China; D004352:Drug Resistance, Microbial; D052918:Environmental Restoration and Remediation / Q000379:methods*; D005798:Genes, Bacterial; D031323:Iris Plant / Q000254:growth & development / Q000378:metabolism*; D032426:Marantaceae / Q000254:growth & development / Q000378:metabolism*; D012722:Sewage / Q000032:analysis / Q000382:microbiology; D062065:Wastewater / Q000032:analysis* / Q000382:microbiology; D014872:Water Movements; D053833:Wetlands
chemical_list: D000900:Anti-Bacterial Agents; D012722:Sewage; D062065:Wastewater
keywords: Antibiotic resistance genes; Antibiotics; Biodegradation; Constructed wetland; Plant uptake; Substrate adsorption