key: cord-0042162-uvj1ulcn authors: Padhye, Lokesh P.; Tezel, Ulas title: Fate of Environmental Pollutants date: 2014-10-01 journal: Water Environ Res DOI: 10.2175/106143014x14031280668371 sha: b1b64cef7a3712c45100ae7bbb68ad2c567ca601 doc_id: 42162 cord_uid: uvj1ulcn A review of the literature published in 2013 on topics relating to the fate of emerging environmental pollutants during wastewater treatment is presented. This review is divided into the following sections: emerging biological agents, estrogens, metals, nanomaterials, nutrients, persistent organic pollutants, pharmaceuticals and personal care products and herbicide, and trace organic contaminants. Water Environment Research, Volume 86, Number 10-Copyright © 2014 Water Environment Federation pentachlorobenzene (PeCB) and hexachlorobenzene (HCB) to Aldrich humic acid (AHA) and municipal water resource recovery facilities (WRRFs) influent colloidal organic carbon (COC) was investigated using the gas-stripping technique. The logK COC coefficients determined for WRRF influent COC were 3.86, 3.89 and 3.19 for TeCB, PeCB and HCB, respectively and did not follow the expected trend (TeCB < PeCB < HCB) based on hydrophobicity predicted by octanol/water partitioning. COC increased the mass transfer of TeCB, PeCB and HCB with the primary effluent to the secondary biological stage by 8. 7%, 9.6% and 1.2%, respectively. In addition, COC also increased the solubility of TeCB, PeCB and HCB in the primary effluent by 14.4%, 22.0% and 6.5%, respectively (McPhedran et al., 2013) . The occurrence and removal of two groups of polycyclic aromatic hydrocarbons (PAHs) and polychlorinated biphenyls (PCBs) in landfill leachate (LL) treated in three constructed wetland systems (CWs) of different construction and flow regime were investigated. It was confirmed that the major mechanism of PCB and PAH removal in CW systems was adsorption to the bottom sediments (in the SF system) or substrate of the beds (in the SSF systems) as well as adsorption to suspended solids, followed by sedimentation. The compounds characterized by higher octanol/water partition coefficient were more effectively retained in the sediments (Wojciechowska, 2013) . A field study was conducted to determine the occurance and removal of short chain chlorinated paraffins (SCCPs) during the sewage treatment process in an advanced municipal WRRF in Beijing, China. SCCPs were detected in all sewage water and sludge samples, and 97% of the initial mass loading in raw sewage was found to be associated with suspended matter. After passing through treatment, 0.8% and 72.6% of the initial SCCP mass loading were ultimately found in the effluents and dewatered sludge, respectively, while the remaining 26.6% was biodegraded (Zeng et al., 2013) . Carbon nanofibers grown on the surface of a cordierite honeycomb monolith were tested as catalyst for the ozonation of atrazine (ATZ), bezafibrate, erythromycin, metolachlor, and nonylphenol. The process was evaluated both in laboratory and real conditions. It was shown that the use of carbon nonofibers slightly (by 2%) enhanced the mineralization of the organic pollutants tested compared to single ozonation (Derrouiche et al., 2013) . A study was conducted in order to understand the effects of model quinone compounds and humic acid (HA) on the degradation of 2,4,4'-trichlorobiphenyl (PCB28) by persulfate and the production of SO 4 center dot-from persulfate. It was found that quinones and HA can efficiently activate persulfate for the degradation of PCB28. In addition, the results indicated that production of SO4 center dot-from persulfate and quinones was semiquinone radical-dependent (Fang et al., 2013) . In a study, a quantitative model for the adsorption of atrazine onto GAC surface was developed using the results of potentiometric titrations and three types of adsorption experiments which have been carried out in order to determine the nature and distribution of the functional groups on the GAC surface. Potentiometric titrations indicated the existence of at least two different families of chemical groups on the GAC surface, including phenolic-and benzoic-type surface groups. Thermodynamic calculations suggested atrazine adsorption was mainly facilitated on benzoic-type surface groups on GAC (Grive et al., 2013) . A study carried out an economic assessment on treatment of a synthetic wastewater containing wastewater a mixture of five commercial pesticides by a solar photo-Fenton/MBR combined process. As Initial pesticide concentration tested was ranging from 500 mg/L to 50 mg/L, expressed as dissolved organic carbon concentration. The results suggested that the use of an MBR process permits lower photochemical oxidation requirements than other biological treatments, resulting in approximately 20% photo-Fenton cost reduction for highly polluted wastewater. Overall, 30% total cost reduction can be gained treating higher daily volumes depending on the pollution load with the proposed system . These results indicated that industrial wastewater was one of the major sources of PFOS contamination in the water systems (Boontanon et al., 2013) . Perfluoroalkyl sulfonates (PFASs) and perfluoroalkyl carboxylates (PFACs) were analyzed in sediment samples from the wastewater canal draining the industrial complex of Pancevo, Serbia which includes oil refinery, petrochemical plant, and fertilizer factory. The canal is directly connected to Europe's second largest river, the Danube, which drains its water into the Black Sea. PFOS up to 5.7 ng/g-dry weight (dw) and total perfluorinated compounds (PFCs) up to 6.3 ng/g-dw were detected. Compared to other reports, high levels of PFOS were found, even though PFCs are not used in the industrial production associated with this canal which indicates that PFCs have been transported from other sources (Beskoski et al., 2013) . Bioaccumulation of six kinds of perfluoroalkyl acids (PFAs) in water flea Daphnia magna was studied. The uptake rates of PFAs in D. magna ranged from 178 to 1338 L/kg.d, and they increased with increasing perfluoroalkyl chain length; the elimination rates ranged from 0.98 to 2.82 d -1 . The bioaccumulation factors (BAFs) of PFAs ranged from 91 to 380 L/kg in wet weight after 25 d exposure; they increased with increasing perfluoroalkyl chain length and had a significant positive correlation with the logK ow of PFAs. This indicated that the hydrophobicity of PFAs plays an important role in their bioaccumulation . (Loos et al., 2013) . The formation of PFASs from their precursors in waters is of concern. A study investigating the formation of PFASs through biodegradation of precursors in incubation tests showed that indigenous microorganisms in groundwater were able to biodegrade perfluorooctane sulfonamide (FOSA) to yield PFOS. A 42-d incubation test using sources of groundwater recharge showed that PFOS, perfluorooctanoate, and perfluorononanoate were significantly and remarkably (>= 1.5 x) formed from precursors in street runoff through biodegradation, but not in rainwater or wastewater effluent (Murakami et al., 2013) . were analyzed in sludge from WRRF from Nigeria. Measurements were performed using an analytical Water Environment Research, Volume 86, Number 10-Copyright © 2014 Water Environment Federation were not effectively removed during wastewater treatment. Elevated influent concentration ratios of perfluorobutanoic acid (PFBA) to PFOA and perfluorobutane sulfonate (PFBS) to PFOS in some WRRFs suggested that short chains substitution were adopted in these cities. Cluster analysis showed treatment processes had important impacts on PFASs profiles in effluent and sludge. Average concentration of total PFCAs in influent from each city and its gross domestic product (GDP) had significant positive correlation . 68.2% with a high defluorination efficiency of 54.9% after 12 h and few intermediates of short-chain perfluorinated carboxylic acids (PFCAs) were found. The removal and defluorination rates with the combined AC/PS system were approximately 12 and 19 times higher than those of the PSonly system, respectively. It was found that activated carbon not only removes PFOA through adsorption, but also activates PS to form sulfate radicals that accelerate the decomposition and mineralization of PFOA . In a study by Bisphenol-A (BPA) biodegradation was studied in a MBR under aerobic conditions (Seyhi et al., 2013) along with the effects of the initial BPA concentration and initial COD concentration on BPA biodegradation. The degradation process followed a first-order kinetic (more than 98% of BPA was removed) with a kinetic rate constant of 1.134 h -1 using an initial BPA concentration of 1.0 mg/L. The kinetic rate constant decreased to 0.611 h -1 when the initial BPA concentration increased to 5.0 mg/L while the initial COD concentration (400 and 2,000 mg/L) did not affect the biodegradation kinetic of BPA. The aim of the study by Bohdziewicz and Kaminska (2013) was to determine the sorption potential of carbon nanotubes (CNTs) to BPA contained in synthetic wastewater whose composition corresponds to biologically treated effluents. Their kinetics study indicated that adsorption of BPA on CNTs proceeded very fast, with the majority of the adsorbate being adsorbed in the first few seconds. The sorption capacity of nanotubes to BPA was the highest for single-walled CNTs. The work by Huang et al. (2013) Benzotriazole (BTri), 4-and 5-tolyltriazole (4-TTri, 5-TTri) were monitored by Herzog et al. (2014) over one year in three WRRFs with a MBR and two conventional activated sludge systems (CAS-E, CAS-M). 5-TTri was removed best (mean removal 80%) in the WRRF mainly by biodegradation followed by BTri (mean removal 45%) and 4-TTri (mean removal 15%) that showed a significant lower elimination. All three WRRF proved a point source for these BTs into the aquatic environment but its impact strongly depended on the upstream water quality within the receiving river system. In the study by Rakshita et al. (2013) , authors aimed to assess the sorption mechanisms of ciprofloxacin Application of mesoporous C-and C, N-codoped TiO 2 in the removal of diclofenac from water was studied by Buda and Czech (2013 was successfully correlated to physical-chemical properties or molecular structure. By mass loading, 95% of all measured micropollutants in the biologically treated hospital wastewater feeding the post-treatments consisted of iodinated contrast media (ICM) while for the total load of analyzed pharmaceuticals and metabolites excluding ICM the elimination by zonation, PAC, and UV at the same conditions was 90%, 86%, and 33%, respectively. Wastewater from a pharmaceutical formulation facility was treated with a biological activated-sludge system followed by ozonation (Lester et al., 2013) . Ozone efficiently degraded CBZ: at an O 3 dose-to-dissolved organic carbon ratio of 0.55 (O 3 /DOC), the concentration of CBZ was reduced by >99% while a lower removal rate was observed for Venlafaxine (VLX), which was decreased by States indicated that the model generated concentration estimates that were accurate to within at least one order of magnitude for a diverse set of drug compounds. A photocatalytically active stainless steel filter (P-SSF) was prepared by Ramasundaram et al. (2013) integrating electrospun TiO 2 nanofibers on SSF surface through a hot-press process where a poly(vinylidene fluoride) (PVDF) nanofibers interlayer acted as a binder. By quantifying the photocatalytic oxidation of cimetidine under ultraviolet radiation and assessing the stability of TiO 2 nanofibers integrated on the P-SSF against sonication, the optimum thickness of the TiO 2 and PVDF layer was determined. The main objective of the study by Rivera-Utrilla et al. (2013) The objective of the work by was to investigate the effectiveness of ultrasonic radiation for the degradation of tetracycline. Their results showed that the ultrasonic degradation of tetracycline followed pseudo first-order kinetics. The tetracycline degradation rate is highly pH-dependent and favored at higher pH. The study by Xiao et al. (2013) investigated the oxidative transformation kinetics of acetaminophen (APAP) by delta-MnO 2 under different conditions. APAP was rapidly oxidized by delta-MnO2 with the generation of Mn 2+ . The measured APAP reaction rate considerably increased with an increase in initial delta-MnO 2 and APAP concentration, but decreased as pH increased. In the study by Xu, Sheng et al. (2013) , the roles of EPS in the migration and removal of sulfamethazine (SMZ), in activated sludge process were investigated. Their results showed that removal of SMZ was influenced by interaction with EPS and SMZ could be effectively adsorbed on EPS, which accounted for up to 61.8% of total SMZ adsorbed by sludge at the initial adsorption stage and declined to around 35.3% at the subsequent biodegradation stage. The enrichment of SMZ by EPS was beneficial for SMZ removal and acquisition by microbes at the subsequent biodegradation stage. The study by reported the absolute rate constants for reaction of diclofenac sodium and model compound (2, 6-dichloraniline) with the two major AO/RP radicals: the hydroxyl radical (center dot OH) and hydrated electron (e aq -). The bimolecular reaction rate constants (M -1 s -1 ) for diclofenac for center dot OH was 9.29 ± 0.11 x 10 9 , and for e aq was 1.53 ± 0.03 x 10 9 . The paper by Zhao, Feng et al. (2013) investigated the effects of selected common chemical species in natural waters (HCO 3 -, NO 3 and humic acids (HA)) on the photodegradation of amoxicillin (AMO) under simulated irradiation using a 300 W xenon lamp. Their results indicated that AMO photodegradation followed pseudo-first-order kinetics. Bicarbonate, as a hydroxyl radical (center dot OH) scavenger, also adversely affected AMO photodegradation. Methods using biological analysis, Xenopus model for thyroid disruption and the medaka model for oestrogenic disruption, were used for assessing endocrine disruption potential of wastewater samples (Castillo et al., 2013) . Assays using the genetically modified organisms were conducted on 9 influent and 32 effluent samples. The thyroidal effect of wastewater was either reduced or removed by the treatment plant; no oestrogenic effect was detected in any of the wastewater samples. A fluidized bed reactor, filled with laccase-based beads, was employed to bioremediate aqueous solutions polluted by endocrine disruptors, octylphenol and nonylphenol (Catapane et al., 2013 Australian sewage treatment works and a receiving river were predicted (simulated) to be similar to those observed in the UK and Europe, exceeding the combined estradiol equivalent's predicted no effect concentration for feminization in wild fish. Furthermore, by 2050 a moderate increase in estrogenic contamination and the potential risk to wildlife was predicted with up to a 2-fold rise in concentrations. A real field water sample was fortified at the part-per-billion level (50 µg/L) with estrone-3-sulfate (E1-3S) before being ozonated (Bourgin et al., 2013) . The estrogenic activity of these water samples spiked with E1-3S before and after treatment was assessed by the ER-CALUX assay and was found to decrease significantly after 10 min of ozonation. This methodological strategy demonstrated its suitability and relevancy for revealing unknown compounds generated from water treatment, and permitted to generate new results regarding specifically the impact of ozonation on estrone-3-sulfate. The study by Mashtare et al. (2013) while Cland Fe 3+ inhibited that process (5.2% and 3.1%, respectively). A model for the photocatalytic degradation of EE2 was found to be in good agreement with experimental profiles. To assess the potential risks on this irrigation practice, the degradation kinetics and mechanisms of 17 alpha-estradiol-3-sulfate were systematically investigated in aqueous solutions blended with dairy wastewater by Zheng et al. (2013) (Chamorro et al., 2013) . oxalic acids were all identified as the degradation products of NP-10; however, the common carboxylic acid was found to be formic acid for every treatment processes tested. The percent relative inhibition towards Vibrio fischeri increased from 9% to 33% and 24% after 120 min-UV C and H 2 O 2 /UV C treatment, respectively. Complete NP-10 and 70% of its total organic carbon (TOC) content was removed by the photo-Fenton process, which ensured the fastest removal rates and lowest inhibitory effect (8% after 120 min treatment). The acute toxicity pattern being observed during H 2 O 2 /UV C and photo-Fenton treatment positively correlated with temporal evolution of the identified carboxylic acids, whereas unidentified oxidation products were the most likely origin of the acute toxicity in UV C photolysis (Karci et al., 2013) . (concentration that causes 50% inhibition of the response) values, the potential risks to aquatic, sediment-dwelling, and terrestrial organisms from these reported concentrations are low (Wang, Steer et al., 2013) In another study, the occurrence and fate of four and D5 in anaerobic compartments . In a study by Ducom et al. (2013) Engineered nanomaterials (ENMs) already occur in sewage and wastewater biosolids due to their release from commercial products (Westerhoff et al., 2013) . Increasing levels and diversity of nanomaterials may enter sewage and WRRFs in the future as they are released from products containing nanomaterials (e. g., coatings) embedded in products, or from industrial processes that use nanomaterials (e. g., polishing). Some metallic nanomaterials may dissolve (e. g., silver-, zinc-, or copperbased) or biodegrade (e. g., fullerenes) in wastewater, and subsequently sorb to settable biomass, precipitate as inorganic solids, or form stable aqueous complexes. WRRFs, leading to their removal from water, but accumulation in biosolids that are disposed to land surface spreading fields, landfills, or incineration where their fate needs to be further considered. Because of the dense biological communities in WRRF unit processes, under typical conditions, >90% of the nanomaterials may attach to biomass, which is removed within the WRRF. Additional research is needed to be able to monitor the transformation and removal of nanomaterials throughout WRRFs and biosolids treatment to assure they are not released into the environment where they may pose human or ecological risks. To better assess the potential risk of ENMs to the environment via input through WRRF effluents, a review by Neale et al. (2013) considered ENM detection methods, fate in WRRFs and potential effects on biota exposed to wastewater associated ENMs. Characterising ENMs in complex matrices presented many challenges, especially at low concentrations. Combining separation methods with techniques to assess particle size and chemical composition appeared to be the most suitable approach for wastewater. The removal performance of heavy metals, Be, Sc, V, Cr, Mn, Co, Ni, Cu, Zn, As, Mo, Cd, Ba, Sn, Sb, Pb and U, by two experimental full-scale membrane bioreactors (microfiltration and ultrafiltration) and the influence of activated sludge TSS concentration were studied by Arevalo et al. (2013) under real operational conditions. Removal efficiencies up to 80% were obtained regardless of whether microfiltration or ultrafiltration membranes were used, except for As, Mo and Sb. Authors found that the removal yields of different heavy metals can be strengthened by increasing the activated sludge TSS concentration, mainly at concentrations above 10 g/L. The study by Awual et al. (2013) (Rounsefell et al., 2013) . In a study, the use of low-cost, consumer level, UV based disinfection systems coupled to constructed wetlands for wastewater treatment in three constructed wetlands in Israel, Jordan and in the Palestinian Authority. Stabilized wetland system efficiently treated the COD. The UV system coupled with the wetland was able to inactivate indicator bacteria (fecal and E. coli) to levels suitable for irrigation even at low UV transmission (Azaizeh et al., 2013) . In another study conducted in Italy, the wastewater disinfection process with ozone applied to a medium size WRRF which has high organic and industrial load (45,000 Population Equivalents) was presented with a view to assessing the microbiological abatement efficacy and the presence of dangerous substances. Ozone disinfection applied was inefficient to satisfy discharge criterion set by EU Directive 2000/60/EC which is 5,000 CFU/100 mL (Ostoich et al., 2013) . (Fisher et al., 2013) . In a study by Schaar et al. (2013) , an ozonation plant designed mainly for micropollutant removal from tertiary effluent was tested also for its pathogen removal efficiency. At specific ozone consumptions of 0.6 and 0.9 g O 3 /g dissolved organic carbon (DOC) a 2-log colony forming unit (CFU) reduction was achieved for indigenous Escherichia coli and enterococci, and the limits of the European bathing water directive for the excellent quality of inland waters were met. In addition, the surrogate virus MS2 was reduced by 4-5 log while no significant inactivation was detected for B. subtilis spores (Schaar et al., 2013) . concern with regards to the presence of ARB and ARGs is their effective removal from wastewater (Bouki et al., 2013 (Chen and Zhang, 2013a) . Abundance of four tetracycline resistance genes (tetM, tetO, tetQ and tetW) and two sulfonamide resistance genes (still and sulII) were determined in 4 municipal and 8 rural WRRFs with different wastewater handling abilities and treatment processes using quantitative polymerase chain reaction (qPCR). Significant reductions (1-3 orders of magnitude) in ARGs were observed in municipal wastewater treatment systems, but a smaller reduction was found in the rural domestic sewage treatment systems (Chen and Zhang, 2013b (Fahrenfeld et al., 2013) . Enterococcus spp. from two poultry farms and proximate surface and ground water sites in an area of intensive poultry production were tested for resistance to 16 clinical antibiotics in study conducted by Furtula et al. (2013) . Resistance patterns were compared to assess trends and possible correlations for specific antimicrobials and levels of resistance. Overall, 86% of litter isolates, 58% of surface water isolates and 100% of ground water isolates were resistant to more than one antibiotic. The results suggested that antibiotic resistance in the water environment was mainly due to the presence of antibiotic residuals originated from the poultry farms (Furtula et al., 2013) . Changes in the total (intrinsic and acquired) resistance of bacteria in a river which is a receiver of treated wastewater were monitored. An increase in the populations of tetracycline-resistant and fluoroquinoloneresistant microorganisms was noted in downstream river water samples in comparison with upstream river water samples, but the above trend was not observed in bacteria resistant to macrolides and beta-lactams. The counts of doxycycline-resistant bacteria were significantly correlated with doxycycline levels which indicated that the presence of doxycycline-resistant bacteria is a robust indicator of anthropogenic stress in river water (Harnisz, 2013 (Johnning et al., 2013) . A study assessed the impact of the activated sludge process on fluoroquinolone resistance. Large collections of CIP-resistant Enterobacteriaceae strains from sludge (n = 112) and from raw sewage (n = 89) was screened for resistance genes and mobile genetic elements. Plasmid-mediated quinolone resistance determinants were readily detected in isolates from both environments. However, resistance determinants were more abundant in bacteria isolated from sludge than raw sewage which indicates resistance is disseminated in the activated sludge (Kaplan et al., 2013) . (Leclercq et al., 2013) . the wastewater from swine feedlots and the correspondingly impacted agricultural fields in Beijing were investigated using culture independent methods. Resistance genes were present in all samples, with the highest absolute concentrations of 1.50 x 10 6 copies/g in soil and 6.69 x 10 6 copies/mL in wastewater. Significant correlations were found between chloramphenicolresistance genes and chloramphenicol residues (r = 0.79, p = 0.0008) as well as between chloramphenicol-resistance genes in swine feedlots and corresponding agricultural soils and wastewater (Li, Shi et al., 2013) . lincomycin residues in water and soil samples collected from multiple sites near wastewater discharge areas were investigated. Sixteen lincomycin-resistance and 16S rRNA genes were detected using real-time PCR. A gradual reduction in the levels of lincomycin-resistance genes and lincomycin residues in the waters and soils were detected from multiple sites along the path of wastewater discharging to the surrounding environment from the swine farms. Significant correlations were found between levels of lincomycin-resistance genes in paired water and soil samples (r = 0.885, p= 0.019), and between lincomycinresistance genes and lincomycin residues (r = 0.975, p < 0.01). This study showed the potential risk of dissemination of lincomycin-resistance genes associated with lincomycin residues in surrounding environments adjacent to swine farms (Li, Sun et al., 2013) . Effect of WRRF discharges on the prevalence of ARGs and bacterial community composition in biofilm and sediment samples of a receiving river was investigated using culture-independent approaches such as quantitative Although secondary treatment seems to decrease the amount of KPC producers in sewage, multidrug-resistant isolates are continually disposed in the urban river (Picao et al., 2013) . To assess the extent of transmission of antibiotic resistances from human sources into the environment, the resistance patterns of Escherichia coli strains isolated from human patients were compared to those found in strains isolated from sewage sludge by Reinthaler et al. (2013) . The results showed that multi drug resistance was evolved parallel in the environment and human (Reinthaler et al., 2013) . A study investigated the resistance of environmental Rhodospirillaceae isolated in the catchment area of the river Swist (Germany) to antibiotics used in human medicine. In total, 614 isolates were tested for antibiotic susceptibility. Resistant Rhodospirillaceae were detected in wastewater effluent from a municipal sewage treatment plant, as well as in non-polluted upper reaches. The highest multi-resistance level was detected in small tributaries and it surprisingly decreased with an increasing influence of municipal wastewater which indicated that the detected resistances were acquired rather than intrinsic (Schreiber and Kistemann, 2013) . In another study, the diversity of culturable antibiotic resistant bacteria from treated and raw wastewaters was identified by a modified standard agar recovery method and subsequent pyrosequencing. . It has been suggested that laterally transferred genetic agents, such as integrons, play a role in the spread of resistant bacteria throughout ecosystems. The distribution of three integron classes throughout a coastal estuarine ecosystem was compared in a study by Uyaguri et al. (2013) . Integron distribution patterns were determined in the sediment and water collected at seven sites throughout two estuaries with different levels of anthropogenic input by qPCR. The results showed that all three integron classes were present in each sample. However, the relative abundance was different; with class 2 integrons significantly elevated in areas of high anthropogenic input and class I integrons elevated in areas of low input (Uyaguari et al., 2013) . In a study, the occurrence of vancomycin resistant enterococci (VRE) in a hospital effluent and in the receiving urban WRRF was investigated. Vancomycin and CIP resistant bacteria occurred in the hospital effluent and in raw municipal inflow at densities of 10 3 to 10 2 CFU/mL, being significantly more prevalent in the hospital effluent than in the urban wastewater. Most of the VRE isolated from the hospital effluent belonged to the species Enterococcus faecalis and Enterococcus faecium and presented multidrug-resistance phenotypes to CIP, tetracycline, erythromycin, and high-level gentamicin. Thus results suggested that hospital effluents discharged into urban WRRF may be a relevant source of resistance spread to the environment (Varela et al., 2013) . Occurrence, diversity and abundance of antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs) in aerobic and anaerobic sludge of a full-scale tannery WRRF were investigated using Illumina highthroughput sequencing. Sequencing reads from aerobic and anaerobic sludge revealed differences in the abundance of functional genes between both microbial communities. Genes coding for antibiotic resistance were identified in both communities. Aerobic and anaerobic sludge contained various ARGs with high abundance, such as sulfonamide resistance genes. Tetracycline resistance genes were highly rich in the anaerobic sludge compared to aerobic sludge. Over 70 types of insertion sequences were detected in each sludge sample, and class 1 integrase genes were prevalent in the WRRF . The IncF antibiotic resistance and virulence plasmid pRSB225, isolated from an unknown bacterium released with the treated wastewater from a municipal WRRF into the environment has been analyzed at the genomic level by pyrosequencing. The accessory modules of the plasmid mainly comprise genes conferring resistance to ampicillin, chloramphenicol, erythromycin, kanamycin and neomycin, streptomycin, sulphonamides, tetracycline and trimethoprim, as well as mercuric ions (Wibberg et al., 2013) The molecular architecture of class 2 integrons among gram-negative bacteria from wastewater environments was investigated in Jinan, China. Out of the 391 antibiotic-resistant bacteria isolated, 38 isolates harboring class 2 integrons encoding potentially transferrable genes that could confer antibiotic resistance were found. Results showed that water sources in the Jinan region harbored a diverse community of both typical and atypical class 2 integrons, raising concerns about the overuse of antibiotics and their careless disposal into the environment . In a study, the transfer discipline and dissemination of the RP4 plasmid in MBRs were investigated by the counting plate method, the MIDI microorganism identification system, and quantitative polymerase chain reaction (qPCR) techniques. The results showed that the average transfer frequency of the RP4 plasmid from the donor strain to cultivable bacteria in MBR system was greater than the transfer frequency in wastewater and conventional system reported previously. This suggests that antibiotic resistance can be disseminated faster in MBR systems . However, both disinfection processes were not effective in the inactivation of ARB, and the simultaneous release of ARB and antibiotics at sub-lethal concentrations into WRRF effluent may promote the development of resistance among bacteria in receiving water . Efficiency of two vertical flow constructed wetlands characterized by volcanic (CW1) and zeolite (CW2) respectively, at removing three common antibiotics (CIP HCl, oxytetracycline HCl, and sulfamethazine) and tetracycline resistance (tet) genes (tetM, tetO, and tetW) from swine wastewater was investigated. The result indicated that the two systems could significantly reduce the wastewater antibiotics content, and elimination rates were in the following sequence: oxytetracycline > CIP > sulfamethazine. The zeolite-medium system was superior to that of the volcanic-medium system both in antibiotic and resistance gene removal . Treatment of Wastewater Contaminated with Detergents and Mineral Oils Using Effective and Scalable Technology Performance of a Constructed Wetland in Grand Marais, Manitoba, Canada: Removal of Nutrients, Pharmaceuticals, and Antibiotic Resistance Genes from Municipal Wastewater Removal Performance of Heavy Metals in Mbr Systems and Their Influence in Water Reuse Selective Lanthanide Sorption and Mechanism Using Novel Hybrid Lewis Base Ligand Modified Constructed Wetlands Combined with UV Disinfection Systems for Removal of Enteric Pathogens and Wastewater Contaminants Photolytic Degradation of Norfloxacin, Enrofloxacin and Ciprofloxacin in Various Aqueous Media Complete Hydrodehalogenation of Polyfluorinated and Other Polyhalogenated Benzenes under Mild Catalytic Conditions Perfluorinated Compounds in Sediment Samples from the Wastewater Canal of Pancevo (Serbia) Industrial Area Identification of Viral Pathogen Diversity in Sewage Sludge by Metagenome Analysis Mass Loading and Fate of Linear and Cyclic Siloxanes in a Wastewater Treatment Plant in Greece Kinetics and Equilibrium of the Sorption of Bisphenol A by Carbon Nanotubes from Wastewater Behavior of Engineered Nanoparticles in Landfill Leachate Direct Photolysis of Human Metabolites of the Antibiotic Sulfamethoxazole: Evidence for Abiotic Back-Transformation Perfluorooctane Sulfonate in the Water Environment of Combined Effects of Biosolids Application and Irrigation with Reclaimed Wastewater on Transport of Pharmaceutical Compounds in Arable Soils Detection and Fate of Antibiotic Resistant Bacteria in Wastewater Treatment Plants: A Review Differential Chemical Profiling to Identify Zonation by-Products of Estrone-Sulfate and First Characterization of Estrogenicity in Generated Drinking Water Effect of Wastewater Colloids on Membrane Removal of Antibiotic Resistance Genes Preparation and Characterization of C,N-Codoped TiO 2 Photocatalyst for the Degradation of Diclofenac from Wastewater Aerobic Digestion Reduces the Quantity of Antibiotic Resistance Genes in Residual Municipal Wastewater Solids Air-Drying Beds Reduce the Quantities of Antibiotic Resistance Genes and Class 1 Integrons in Residual Municipal Wastewater Solids Continuous-Flow Photocatalytic Treatment of Pharmaceutical Micropollutants: Activity, Inhibition, and Deactivation of TiO 2 Photocatalysts in Wastewater Effluent Evaluating Nutrient Impacts in Urban Watersheds: Challenges and Research Opportunities In Vivo Endocrine Disruption Assessment of Wastewater Treatment Plant Effluents with Small Organisms Enzymatic Removal of Estrogenic Activity of Nonylphenol and Octylphenol Aqueous Solutions by Immobilized Laccase from Trametes Versicolor Pulp Mill Discharges Real-Time Forecasting of Hong Kong Beach Water Quality by 3D Degradation of Phenol by Using Magnetic Photocatalysts of Titania Evidence and Recommendations to Support the Use of a Novel Passive Water Sampler to Quantify Antibiotics in Wastewaters Preparation and Characterization of PbO 2 Electrode and Its Application in Electro-Catalytic Degradation of o-Aminophenol in Aqueous Solution Assisted by CuO-Ce2O3/Gamma-Al2O3 Catalyst Effects of Advanced Treatment Systems on the Removal of Antibiotic Resistance Water Environment Research Occurrence and Removal of Antibiotic Resistance Genes in Municipal Wastewater and Rural Domestic Sewage Treatment Systems in Eastern China Preparation and Characterization of Palladium Nano-Crystallite Decorated TiO2 Nano-Tubes Photoelectrode and Its Enhanced Photocatalytic Efficiency for Degradation of Diclofenac Colloidal Properties and Stability of Graphene Oxide Nanomaterials in the Aquatic Environment Electrochemical Degradation of M-Cresol Using Porous Carbon-Nanotube-Containing Cathode and Ti/SnO 2-Sb2O5-IrO2 Anode: Kinetics, Byproducts and Biodegradability Effect of Intermediate Compounds and Products on Wet Oxidation and Biodegradation Rates of Pharmaceutical Compounds Degradation of Pharmaceuticals in Non-Sterile Urban Wastewater by Trametes Versicolor in a Fluidized Bed Bioreactor Bioaccumulation and Uptake Routes of Perfluoroalkyl Acids in Daphnia Magna Modelling of E. coli Distribution in Coastal Areas Subjected to Combined Sewer Overflows Cofe2o4 Magnetic Nanoparticles as a Highly Active Heterogeneous Catalyst of Oxone for the Degradation of Diclofenac in Water Process Design for Wastewater Treatment: Catalytic Ozonation of Organic Pollutants Hydrolysis of Reductive Degradation of Oxygenated Polycyclic Aromatic Hydrocarbons Using an Activated Magnesium/Co-Solvent System Reclaimed Water as a Reservoir of Antibiotic Resistance Genes: Distribution System and Irrigation Implications Activation of Persulfate by Quinones: Free Radical Reactions and Implication for the Degradation of PCBs Nitrogen and Copper Doped Solar Light Active TiO 2 Photocatalysts for Water Decontamination Relative Importance of the Humic and Fulvic Fractions of Natural Organic Matter in the Aggregation and Deposition of Silver Nanoparticles Antimicrobial Resistance in Enterococcus spp. Isolated from Environmental Samples in an Area of Intensive Poultry Production Comparative Analysis of Effluent Water Quality from a Municipal Treatment Plant and Two on-Site Wastewater Treatment Systems The Influence of Light Exposure, Water Quality and Vegetation on the Removal of Electro-Fenton Method Oxidation of Salicylic Acid in Aqueous Solution with Graphite Electrodes Modeling of Steroid Estrogen Contamination in Uk and South Australian Rivers Predicts Modest Increases in Concentrations in the Future A Quantitative Speciation Model for the Adsorption of Organic Pollutants on Activated Carbon Adsorption and Fenton-Like Degradation of Naphthalene Dye Intermediate on Sewage Sludge Derived Porous Carbon Microbial Selectivity of Uv Treatment on Antibiotic-Resistant Heterotrophic Bacteria in Secondary Effluents of a Municipal Wastewater Treatment Plant Ultraviolet Reduction of Erythromycin and Tetracycline Resistant Heterotrophic Bacteria and Their Resistance Genes in Municipal Wastewater Biological Phosphorus Removal Inhibition by Roxarsone in Batch Culture Systems Novel Photo-Sulfite System: Toward Simultaneous Transformations of Inorganic and Organic Pollutants Total Resistance of Native Bacteria as an Indicator of Changes in the Water Environment The Effect of Hospital Effluent on Effects of Aggregate Structure on the Dissolution Kinetics of Citrate-Stabilized Silver Nanoparticles Modeling Approaches for Characterizing and Evaluating Environmental Exposure to Engineered Nanomaterials in Support of Risk-Based Decision Making Monitoring Benzotriazoles: A 1 Year Study on Concentrations and Removal Efficiencies in Three Different Wastewater Treatment Plants Differential Microbial Transformation of Nitrosamines by an Inducible Propane Monooxygenase Removal of Zno Nanoparticles in Simulated Wastewater Treatment Processes and Its Effects on Cod and Nh4+-N Reduction Persistence of Perfluoroalkyl Acid Precursors in AFFF-Impacted Groundwater and Soil Identifying New Persistent and Bioaccumulative Organics among Chemicals in Commerce. III: Byproducts, Impurities, and Transformation Products Assessment of the Fe(III)-Edds Complex in Fenton-Like Processes: From the Radical Formation to the Degradation of Bisphenol A Comparative and Integrative Environmental Assessment of Advanced Wastewater Treatment Processes Based on an Average Removal of Pharmaceuticals Biodegradation Characteristics and Size Fractionation of Landfill Leachate for Integrated Membrane Treatment Development of Chemical Reduction and Air Stripping Processes to Remove Mercury from Wastewater Precipitation of Heavy Metals from Coal Ash Leachate Using Biogenic Hydrogen Sulfide Generated from Fgd Gypsum Effects of Electrode Geometry on the Performance of Dielectric Barrier/Packed-Bed Discharge Plasmas in Benzene Degradation Enhanced Sorption of Naphthalene and p-Nitrophenol by Nano-SiO 2 Modified with a Cationic Surfactant Acquired Genetic Mechanisms of a Multiresistant Bacterium Isolated from a Treatment Plant Receiving Wastewater from Antibiotic Production Fate and Transformation of Silver Nanoparticles in Urban Wastewater Systems Fate of Stable Strontium in the Sewage Treatment Process as an Analog for Radiostrontium Released by Nuclear Accidents Characterization of Fluoroquinolone Resistance and Qnr Diversity in Enterobacteriaceae from Municipal Biosolids Oxidation of Nonylphenol Ethoxylates in Aqueous Solution by UV-C Photolysis, H 2O2/UV-C, Fenton and Photo-Fenton Processes: Are These Processes Toxicologically Safe? Single-Walled Carbon Nanotube Transport in Representative Municipal Solid Waste Landfill Conditions Removal of Carbamazepine from Water by a Novel TiO2-Coconut Shell Powder/Uv Process: Composite Preparation and Photocatalytic Activity Pharmaceuticals and Personal Care Products Removal in a Membrane Bioreactor Wastewater Treatment Plant Parameters Affecting the Occurrence and Removal of Polybrominated Diphenyl Ethers in Twenty Canadian Wastewater Treatment Plants Polybrominated Diphenyl Ethers in Sewage Sludge and Treated Biosolids: Effect Factors and Mass Balance Effects of Temperature and Predator on the Persistence of Host-Specific Bacteroides Prevotella Genetic Markers in Water Extended-Spectrum Beta-Lactamase (ESBL)-Positive Enterobacteriaceae in Municipal Sewage and Their Emission to the Environment Antibiotic Resistant Escherichia Coli in Hospital and Municipal Sewage and Their Emission to the Environment Number 10-Copyright © Elimination of Micropollutants During Post-Treatment of Hospital Wastewater with Powdered Activated Carbon, Ozone, and Uv TAML Activator/Peroxide-Catalyzed Facile Oxidative Degradation of the Persistent Explosives Trinitrotoluene and Trinitrobenzene in Mice Liar Solutions Fossil Organic Carbon in Wastewater and Its Fate in Treatment Plants Changes in Enterococcal Populations and Related Antibiotic Resistance Along a Promoted Degradation of Perfluorooctanic Acid by Persulfate When Adding Activated Carbon Biological Treatment of Pharmaceutical Wastewater from the Antibiotics Industry Treating Wastewater from a Pharmaceutical Formulation Facility by Biological Process and Ozone Effect of Chloride on the Dissolution Rate of Silver Nanoparticles and Toxicity to E. Coli Laccase Immobilized onto Poly(GMA-MAA) Microspheres for p-Benzenediol Removal from Wastewater Occurrence of Chloramphenicol-Resistance Genes as Environmental Pollutants from Swine Feedlots Adsorption Removal of Tetracycline from Aqueous Solution by Anaerobic Granular Sludge: Equilibrium and Kinetic Studies Transformation of Cefazolin During Chlorination Process: Products, Mechanism and Genotoxicity Assessment Quantification of Nanoscale Silver Particles Removal and Release from Municipal Wastewater Treatment Plants in Germany Quantification of Lincomycin Resistance Genes Associated with Lincomycin Residues in Waters and Soils Adjacent to Representative Swine Farms in China Different Nanostructured In 2O3 for Photocatalytic Decomposition of Perfluorooctanoic Acid (PFOA) Accelerated Reduction of Chlorinated Nitroaromatic Antibiotic Chloramphenicol by Biocathode Elimination of Veterinary Antibiotics and Antibiotic Resistance Genes from Swine Wastewater in the Vertical Flow Constructed Wetlands Response of Activated Sludge to the Treatment of Oxytetracycline Production Waste Stream Degradation of Sulfamethazine by Gamma Irradiation in the Presence of Hydrogen Peroxide EU-Wide Monitoring Survey on Emerging Polar Organic Contaminants in Wastewater Water Environment Research Fate of Triclocarban, Triclosan and Methyltriclosan During Wastewater and Biosolids Treatment Processes Fate of Arsenate Adsorbed on Nano-TiO2 in the Presence of Sulfate Reducing Bacteria New Insights on Degradation of Methylene Blue Using Thermocatalytic Reactions Catalyzed by Low-Temperature Excitation Sulfidation Mechanism for Zinc Oxide Nanoparticles and the Effect of Sulfidation on Their Solubility Influences of Solid Retention Time, Nitrification and Microbial Activity on the Attenuation of Pharmaceuticals and Estrogens in Membrane Bioreactors Prevalence of Antibiotic Resistance Genes and Bacterial Community Composition in a River Influenced by a Wastewater Treatment Plant Coupling Membrane Separation and Photocatalytic Oxidation Processes for the Degradation of Pharmaceutical Pollutants Transformation of 17 Alpha-Estradiol, 17 Beta-Estradiol, and Estrone in Sediments under Nitrate-and Sulfate-Reducing Conditions Hydrophobic Organic Compound (Hoc) Partitioning Behaviour to Municipal Wastewater Colloidal Organic Carbon Urban Wastewater Treatment Plants as Hotspots for the Release of Antibiotics in the Environment: A Review Antibiotic Resistance in Triclosan Tolerant Fecal Coliforms Isolated from Surface Waters near Wastewater Treatment Plant Outflows Effect of Silver Nanoparticles and Antibiotics on Antibiotic Resistance Genes in Anaerobic Digestion Inhibition and Biotransformation Potential of Naphthenic Acids under Different Electron Accepting Conditions Fate and Effect of Naphthenic Acids on Oil Refinery Activated Sludge Wastewater Treatment Systems Engineering Solutions to Improve the Removal of Fecal Indicator Bacteria by Bioinfiltration Systems During Intermittent Flow of Stormwater Fate of Arsenic During Microbial Reduction of Biogenic Versus Abiogenic as-Fe(III)-Mineral Coprecipitates Levels and Trends of the Emerging Contaminants HBCDs (Hexabromocyclododecanes) and PFCs (Perfluorinated Compounds) in Marine Shellfish Along French Coasts Formation of Perfluorinated Phase Distribution and Removal of Pharmaceuticals and Personal Care Products During Anaerobic Sludge Digestion A Review of the Detection, Fate and Effects of Number 10-Copyright © 2014 Water Environment Federation Engineered Nanomaterials in Wastewater Treatment Plants Removal of Trace Organic Contaminants by an Mbr Comprising a Mixed Culture of Bacteria and White-Rot Fungi Removal of Apis and Bacteria from Hospital Wastewater by Mbr Plus Theoretical and Experimental Insights into the Electrochemical Mineralization Mechanism of Perfluorooctanoic Acid Dynamics of Antibiotic Resistance Genes and Their Relationships with System Treatment Efficiency in a Horizontal Subsurface Flow Constructed Wetland Treatment of Heavy Metals by Iron Oxide Coated and Natural Gravel Media in Sustainable Urban Drainage Systems Effect of Wastewater Chlorination on Endocrine Disruptor Removal Antibiotic Resistance, Antimicrobial Residues and Bacterial Community Composition in Urban Wastewater Control of Evaluation of a Prediction Model for Influent Pharmaceutical Concentrations Oxidation of Dithiocarbamates to Yield N-Nitrosamines by Water Disinfection Oxidants Sol-Gel Synthesis of Mesoporous Mixed Fe 2O3/TiO2 Photocatalyst: Application for Degradation of 4-Chlorophenol Removal Characteristics of Engineered Nanoparticles by Activated Sludge Influence of Chloride and Fe(II) Content on the Reduction of Hg(II) by Magnetite Economic Evaluation of a Combined Photo-Fenton/Mbr Process Using Pesticides as Model Pollutant. Factors Affecting Costs The Route of Antimicrobial Resistance from the Hospital Effluent to the Environment: Focus on the Occurrence of KPC-Producing Aeromonas spp. And Enterobacteriaceae in Sewage Degradation of Endocrine-Disrupting Chemicals During Activated Sludge Reduction by Ozone A Comparison of Various Rural Wastewater Treatment Processes for the Removal of Endocrine-Disrupting Chemicals (Edcs) Mechanisms of Ciprofloxacin Removal by Nano-Sized Magnetite Titanium Dioxide Nanofibers Integrated Stainless Steel Filter for Photocatalytic Degradation of Pharmaceutical Compounds Resistance Patterns of Escherichia coli Isolated from Water Environment Federation Sewage Sludge in Comparison with Those Isolated from Human Patients in 2000 and Pharmaceuticals as Emerging Contaminants and Their Removal from Water Advanced Treatment of Urban Wastewater by UV Radiation: Effect on Antibiotics and Antibiotic-Resistant E. coli Strains Relationship between Phenol Degradation Efficiency and Microbial Community Structure in an Anaerobic SBR Fate of Pathogen Indicators in a Domestic Blend of Food Waste and Wastewater through a Two-Stage Anaerobic Digestion System Synthesis of Graphene-Zno-Au Nanocomposites for Efficient Photocatalytic Reduction of Nitrobenzene Fate of Selected Pharmaceuticals and Synthetic Endocrine Disrupting Compounds During Wastewater Treatment and Sludge Anaerobic Digestion Microorganism Inactivation by an Ozonation Step Optimized for Micropollutant Removal from Tertiary Effluent Antibiotic Resistance among Autochthonous Aquatic Environmental Bacteria Occurrence and Fate of Dissolved and Particulate Antimicrobials in Municipal Wastewater Treatment Biodegradation of Bisphenol-A in Aerobic Membrane Bioreactor Sludge Pyrosequencing Estimates of the Diversity of Antibiotic Resistant Bacteria in a Wastewater System Bioavailable and Biodegradable Dissolved Organic Nitrogen in Activated Sludge and Trickling Filter Wastewater Treatment Plants Per-and Polyfluoroalkyl Substances in Selected Sewage Sludge in Nigeria Dynamic Assessment of the Floc Morphology, Bacterial Diversity, and Integron Content of an Activated Sludge Reactor Processing Hospital Effluent Psychoactive Pharmaceuticals in Sludge and Their Emission from Wastewater Treatment Facilities in Korea Deashing Treatment on Biochar Structural Properties and Potential Sorption Mechanisms of Phenanthrene Levels, Profile and Distribution of Dechloran Plus (DP) and Polybrominated Diphenyl Ethers (PBDEs) in the Environment of Pakistan Haloacetic Acid Removal by Sequential Zero-Valent Iron Reduction and Biologically Active Carbon Degradation Magnetic TiO 2-Graphene Composite as a High-Performance and Recyclable Platform for Efficient Photocatalytic Removal of Herbicides from Water Major Pharmaceutical Residues in Wastewater Treatment Plants and Receiving Waters in Bangkok, Thailand, and Associated Ecological Risks Antibiotic Resistant Staphylococcus aureus in Water Environment Federation Hospital Wastewaters and Sewage Treatment Plants with Special Reference to Methicillin-Resistant Staphylococcus aureus (MRSA) Sustainable Biodegradation of Phenolic Endocrine-Disrupting Chemicals by Phragmites Australis-Rhizosphere Bacteria Association Degradation of Caffeine by Photo-Fenton Process: Optimization of Treatment Conditions New Biodegradable Organic-Soluble Chelating Agents for Simultaneous Removal of Heavy Metals and Organic Pollutants from Contaminated Media Removal of Pharmaceuticals from a Wwtp Secondary Effluent by Abundance of Class 1-3 Integrons in South Carolina Estuarine Ecosystems under High and Low Levels of Anthropogenic Influence Calibration and Field Test of the Polar Organic Chemical Integrative Samplers for the Determination of 15 Endocrine Disrupting Compounds in Wastewater and River Water with Special Focus on Performance Reference Compounds (Prc) Vancomycin Resistant Enterococci: From the Hospital Effluent to the Urban Wastewater Treatment Plant National Inventory of Alkylphenol Ethoxylate Compounds in U.S. Sewage Sludges and Chemical Fate in Outdoor Soil Mesocosms National Inventory of Perfluoroalkyl Substances in Archived Us Biosolids from the 2001 Epa National Sewage Sludge Survey Performance of a Biofilter System with Agave Fiber Filter Media for Municipal Wastewater Treatment The Use of Hybrid Constructed Wetlands for Wastewater Treatment with Special Attention to Nitrogen Removal: A Review of a Recent Development Review of Recent Advances in Research on the Toxicity, Detection, Occurrence and Fate of Cyclic Volatile Methyl Siloxanes in the Environment Concentrations of Cyclic Volatile Methylsiloxanes in Biosolid Amended Soil, Influent, Effluent, Receiving Water, and Sediment of Wastewater Treatment Plants in Canada Modeling of Quantitative Effects of Water Components on the Photocatalytic Degradation of 17 Alpha-Ethynylestradiol in a Modified Flat Plate Serpentine Reactor First Report of a Chinese PFOS Alternative Overlooked for 30 Years: Its Toxicity, Persistence, and Presence in the Environment Schwertmannite as a New Fenton-Like Catalyst in the Oxidation of Phenol by H 2O2 Fe3O4 Nanoparticles as an Efficient Heterogeneous Fenton Catalyst for Phenol Removal at Relatively Wide pH Values Degradation of Tetracycline in Water by Ultrasonic Irradiation Metagenomic Profiling of Antibiotic Resistance Genes and Mobile Genetic Elements in a Tannery Wastewater Treatment Plant Distinct Photolytic Mechanisms and Products for Different Dissociation Species of Ciprofloxacin Nanomaterial Removal and Transformation During Biological Wastewater Treatment The IncF Plasmid PRSB225 Isolated from a Municipal Wastewater Treatment Plant's on-Site Preflooder Combining Antibiotic Resistance and Putative Virulence Functions is Highly Related to Virulence Plasmids Identified in Pathogenic E. coli Isolates Removal of Persistent Organic Pollutants from Landfill Leachates Treated in Three Constructed Wetland Systems Occurrence and Removal Efficiency of Six Polycyclic Aromatic Hydrocarbons in Different Wastewater Treatment Plants Molecular Diversity of Class 2 Integrons in Antibiotic-Resistant Gram-Negative Bacteria Found in Wastewater Environments in China Transformation of Acetaminophen Using Manganese Dioxide -Mediated Oxidative Processes: Reaction Rates and Pathways Roles of Extracellular Polymeric Substances (EPS) in the Migration and Removal of Sulfamethazine in Activated Sludge System Source Apportionment of Perfluorinated Compounds (PFCs) in Sediments: Using Three Multivariate Factor Analysis Receptor Models Occurrence and Fate of Volatile Siloxanes in a Municipal Wastewater Treatment Plant of Beijing Selective Removal of Arsenic and Monovalent Ions from Brackish Water Reverse Osmosis Concentrate Horizontal Transfer of Antibiotic Resistance Genes in a Membrane Bioreactor Oxidation of Bisphenol A by Permanganate: Reaction Kinetics and Removal of Estrogenic Activity Competitive Removal of Two Contaminants in a Goethite-Catalyzed Fenton Process at Neutral pH Fate of Bulk and Trace Organics During a Simulated Aquifer Recharge and Recovery (ARR)-Ozone Hybrid Process Occurrence and Fate of N-Nitrosamines and Their Formation Potential in Three Wastewater Treatment Plants in Japan Comprehensive Assessment of Hormones, Phytoestrogens, and Estrogenic Activity in an Anaerobic Swine Waste Lagoon Degradation of Diclofenac by Advanced Oxidation and Reduction Processes: Kinetic Studies, Degradation Pathways and Toxicity Assessments Efficient Degradation of Contaminants of Emerging Concerns by a New Electro-Fenton Process with Reaction of Silver Nanoparticles in the Disinfection Process Nanofiltration Membrane Bioreactor for Removing Pharmaceutical Compounds Behavior, Fate, and Mass Loading of Short Chain Chlorinated Paraffins in an Advanced Municipal Sewage Treatment Plant The Heavy Metal Partition in Size-Fractions of the Fine Particles in Agricultural Soils Contaminated by Waste Water and Smelter Dust Distribution and Fate of Perfluoroalkyl Substances in Municipal Wastewater Treatment Plants in Economically Developed Areas of China The Effects of Operating Parameters on Spiramycin Removal by Nanofiltration Membrane Photodegradation of Amoxicillin in Aqueous Solution under Simulated Irradiation: Influencing Factors and Mechanisms Fate of Estrogen Conjugate 17 Alpha-Estradiol-3-Sulfate in Dairy Wastewater: Comparison of Aerobic and Anaerobic Degradation and Metabolite Formation Nutrient Removal and Biodiesel Production by Integration of Freshwater Algae Cultivation with Piggery Wastewater Treatment