Isolation and genome-wide analysis of the novel Acinetobacter baumannii bacteriophage vB_AbaM_AB3P2.

A lytic Acinetobacter baumannii phage, isolate vB_AbaM_AB3P2, was isolated from a sewage treatment plant in China. A. baumannii phage vB_AbaM_AB3P2 has a dsDNA genome that is 44,824 bp in length with a G + C content of 37.75%. Ninety-six open reading frames were identified, and no genes for antibiotic resistance or virulence factors were found. Genomic and phylogenetic analysis of this phage revealed that it represents a new species in the genus Obolenskvirus. Phage vB_AbaM_AB3P2 has a short latent period (10 min) and high stability at 30-70°C and pH 2-10 and is potentially useful for controlling multi-drug-resistant A. baumannii.

Effect of the residual levofloxacin on hydroponic vegetables with sewage treatment plant tailwater: Microbial community, discharge risk and control strategy.

Tailwater-based hydroponic vegetable is a promising strategy for domestic wastewater recycling. However, the effect of residual antibiotics on the hydroponic vegetable system and the relation between hydroponic culture parameters and the residual water quality are still unclear. Here, the typical antibiotic Levofloxacin (LVFX) was employed, and the effect of LVFX (5 mg/L) on the residual water quality, plant growth and microbial community of water spinach hydroponic culture system were investigated under different hydraulic residence times (HRT). Obvious toxic effects on water spinach were observed, and the highest removal rate of LVFX (about 6 %) and TN (25.67±1.43 %) was observed when HRT was 7 days. Hydroponic culture increased the microbial abundance, diversity, and microbial community stability. To optimize the hydroponic culture, actual sewage plant tailwater spiked with 20 µg/L LVFX, along with three common planting substrates (sponge, ceramsite, and activated carbon) were used for the hydroponic culture of lettuce (seasonal reasons). The inhibition effect of LVFX on the removal of NO3--N and TN was observed even as the LVFX concentration decreased significantly (from 14.62 ± 0.44 µg/L to 0.65 ± 0.07 µg/L). The best growth situation of lettuce and removal rates of NH4+-N, NO3--N, TN, especially LVFX (up to 95.65 ± 0.54 %) were observed in the activated carbon treated group. The overall results indicate the negative effect of residual antibiotics on the hydroponic vegetable systems, and adding activated carbon as substrate is an effective strategy for supporting plant growth and controlling discharged risk.

Comparative assessment of microbiome and resistome of influent and effluent of sewage treatment plant and common effluent treatment plant located in Delhi, India using shotgun approach.

Antimicrobial resistance (AMR) is a significant threat that demands surveillance to identify and analyze trends of the emerging antibiotic resistance genes (ARGs) and potential microbial carriers. The influent of the wastewater treatment plants (WWTPs) reflects the microbes derived from the population and effluent being the source of dissemination of potential pathogenic microbes and AMR. The present study aimed to monitor microbial communities and antibiotic resistance genes in WWTPs employing a whole metagenome shotgun sequencing approach. The samples were collected from a sewage treatment plant (STP) and a common effluent treatment plant (CETP) in Delhi, India. The results showed the influent of STP to be rich in Bifidobacterium, Bacteroides, Escherichia, Arcobacter, and Pseudomonas residents of gut microbiota and known to cause diseases in humans and animals; whereas the CETP sample was abundant in Aeromonas, Escherichia, and Shewanella known to be involved in the degradation of different compounds. Interestingly, the effluent samples from both STPs and CETP were rich in microbial diversity, comprising organic and xenobiotic compound degrading and disease-causing bacteria, indicating the effluent being the source of dissemination of concerning bacteria to the environment. The functional profile at both sites displayed similarity with an abundance of housekeeping function genes as analyzed by Clusters of Orthologous Genes (COG), KEGG Orthology (KO), and subsystem databases. Resistome profiling by MEGARes showed the dominance of ARGs corresponding to beta-lactams having relative abundance ranging from 16% to 34% in all the metagenome datasets, followed by tetracycline (8%-16%), aminoglycosides (7%-9%), multi-drug (5%-9%), and rifampin (3%-9%). Also, AMR genes oxa, ant3-DPRIME, and rpoB, which are of clinical importance were predominantly and most prevalently present in all the samples. The presence of AMR in effluents from both types of treatment plants indicates that wastewater from both sources contributes to the spread of pathogenic bacteria and resistance genes, increasing the environmental AMR burden and therefore requires tertiary treatment before discharge. This work will facilitate further research towards the identification of suitable biomarkers for monitoring antibiotic resistance.

A unified modelling framework for type I (discrete) settling and rising of microplastics in primary sedimentation tanks.

Sewage treatment plants (STPs) are considered as a significant source of microplastic pollution into the terrestrial and aquatic environment. Existing observations suggest that primary treatment accounts for major microplastics removal in STPs, though with high variability due to the complex nature of the polymer compositions, abundance, and sizes in the incoming sewage. Here, we develop a unified modelling framework to simulate the Type I (or discrete) settling or rising behaviour of microplastics to predict their eventual fate in Primary Sedimentation Tank (PST). The model was developed as per the conventional design protocol for PST involving Stokes equation and modifications as per flow regime for settling of nylon and polystyrene microplastics. It was subsequently validated with independent column experiments for both settling (nylon and polystyrene) and rising (low-density polyethylene and polypropylene) microplastics in different size ranges. The validated model was then applied for multiple realistic scenarios of polymer compositions, relative abundance, and size distributions in the incoming sewage. The model predicts removals ranging from 12% to 94% for a mixture of microplastics in the size fraction 0-500 µm. Model simulations also suggest better microplastics removal with the integration of skimming in PST, and optimization of surface overflow velocity.

Modeling and optimizing of an actual municipal sewage plant: A comparison of diverse multi-objective optimization methods.

The activated sludge process of an actual municipal sewage treatment plant was systematically modeled, calibrated, and verified in this study. Identified multi-objective optimization (MOO) methods were employed to optimize the process parameters of the validated model, and the optimal MOO algorithm was obtained by comparing Pareto solution sets. The optimization model consisted of three key evaluation indicators (objective functions), which are the average effluent quality (AEQ), overall cost index (OCI), and total volume (TV) of the biochemical tank, along with 12 more process parameters (decision variables). Three optimization algorithms, i.e., adaptive non-dominated sorting genetic algorithm III (ANSGA-III), non-dominated sorting genetic algorithm II (NSGA-II), and particle swarm algorithm (PSO), were adopted using MATLAB. The comparison of these algorithms demonstrated that the ANSGA-III algorithm had better Pareto solution sets under the triple objective optimization, and the effluent quality of COD, TN, NH4+-N, and TP after optimization decreased by 2.22, 0.47, 0.13, and 0.02 mg/L, respectively. Additionally, the simulated AEQ was reduced by 13% compared to the original effluent, and the OCI and TV decreased from 21,023 kWh d-1 and 17,065 m3 to 20,226 kWh d-1 and 16,530 m3, respectively. The reported ANSGA-III algorithm and the proposed multi-objective method have a promising ability for energy conservation, emission reduction, and upgrading of municipal sewage treatment plants.

Identification by Liquid Chromatography-Tandem Mass Spectrometry and Liquid Chromatography-Quadrupole Time-of-Flight Mass Spectrometry of the Contributor to the Thyroid Hormone Receptor Agonist Activity in Effluents from Sewage Treatment Plants.

3,3',5-Triiodothyroacetic acid (TRIAC) was identified as a major contributor to the activity of thyroid hormone receptor (TR) agonists in environmental water. TRIAC contributed 60-148% of the TR-agonist activity in effluents from sewage treatment plants (STPs). Meanwhile, the contributions of 3,5,3'-triiodothyronine (T3), 3,3',5,5'-tetraiodothyronine (T4), and analogues were <1%. TRIAC concentrations in the range of 0.30-4.2 ng/L are likely enough to cause disruption of the thyroid system in living aquatic organisms. The origin of TRIAC in the STP effluents was investigated by analyzing both STP influents and effluents. Relatively high concentrations of T3 and T4 (2.5 and 6.3 ng/L, respectively) were found only in the influents. TRIAC was identified only in the effluents. These findings suggested that T3 and T4 in STP influents were potentially converted into TRIAC during activated sludge treatment or by other means. The evaluation of TRIAC at relevant environmental concentrations by in vivo assays and an appropriate treatment to reduce the TR activity in sewage are needed.

Characterization and removal of microplastics in a sewage treatment plant from urban Nagpur, India.

Sewage treatment plant (STP) acts as a potential source of microplastic contamination in the environment. The presence of microplastics in the sewage treatment plant is reported over the globe in varying concentrations. Hence, the current study is intended to evaluate the presence and abundance of microplastics occurring in sewage treatment plants in India. The samples were processed through digestion and density separation, followed by microscopic and polymer identification through Fourier transform infrared spectroscopy. Also, different wastewater parameters were studied to analyze their influence. High microplastic concentrations were detected in the influent (1860 ± 265 MPs/L), which reduced by > 90%, to around 148 ± 51 MPs/L in the effluent. The concentration of microplastics in sewage sludge was 830 MPs/kg. The prominent plastic types identified include low-density polyethylene, polypropylene, polyurethane, polyvinyl chloride, and rayon. The smaller particles prevail in the effluent, releasing around 30 billion particles per day to the environment. This suggests that the current STP is efficient in removing the majority of the particles, but considerations are needed to avoid the ecological risks associated.

Efficiency evaluation of sewage treatment plants in Delhi, India, using tolerance-based data envelope analysis.

Correct and effective performance evaluation of wastewater treatment plants is a tough task because of the complex biological, physico-chemical, and biochemical processes and associated variables affecting their performance. Conventionally, the efficiency of sewage treatment plants (STPs) are obtained using some index relating pollutant removal efficiency with energy used or costs. These indicators consider only one variable at a time. This leads to incorrect assessment of efficiency, which in turn could adversely affect decision-making of the regulatory authorities. The data envelope analysis (DEA) method utilizes a Linear programming technique which can handle multiple input/output variables without requiring the cost function. This makes it an appropriate tool for assessing the relative efficiency of treatment plants. The present study assess the efficiency of 30 STPs in Delhi, India, using the tolerance-based DEA model utilizing the variable return of scale (VRS). The uncertainty was incorporated into the model using the tolerance measure. The model is solved using the "Add on" option in spreadsheet toolbox of excel solver. Results reveal that out of the 30 plants considered for the study, 6 are performing well (20%). Further, it was observed that a slight change in the input data leads to instability of the efficiency results. Lastly, the ranking is used to determine the treatment plant with best efficiency under all scenarios for the larger period of the year. Such studies will help in chalking out the best management practices that could be adopted by other regulatory authorities.

Seasonal concentration variation and potential influencing factors of organophosphorus flame retardants in a wastewater treatment plant.

Organophosphate flame retardants (OPFRs) in both of water and sludge phase of influent and effluent of the STP were investigated in Beijing of China in five seasons. Total OPFRs concentrations in water phase of influent in five seasons were between 600 and 838 ng/L, where total OPFRs concentration was the lowest in summer of 2018. In water phase of influent and effluent, two chlorinated OPFRs (TCEP and TCPP) were major. Alkyl OPFRs decreased the most in water phase from influent to effluent. In sludge phase, the OPFRs amounts in winter were the lowest. The main OPFRs in sludge phase were TEHP and EHDP, which can be explained by the two OPFRs properties (log Kow and log Koc). Higher the values of the log Kow and log Koc of OPFRs, more amounts in sludge phase. The mass flow of OPFRs in influent were analysed by Principal Component Analysis (PCA), indicating that the influent amounts of TCEP, TDCP, TCPP and DCP were main OPFRs in four seasons to influence the characteristics of influent. Compared to OPFRs reduction in some STPs in other countries, alkyl and aryl OPFRs reduction rates were higher than chlorinated OPFRs. TBEP, TEHP and TPHP can always be effectively removed in different seasons and different STPs. The analysis methods of Pearson correlation and linear correlation were processed to check the possible factors affecting OPFRs reduction in STP. OPFRs reduction was related to some STP working parameters. Significant correlation also was found between OPFRs properties and reduction.

SARS-CoV-2 in environmental perspective: Occurrence, persistence, surveillance, inactivation and challenges.

The unprecedented global spread of the severe acute respiratory syndrome (SARS) caused by SARS-CoV-2 is depicting the distressing pandemic consequence on human health, economy as well as ecosystem services. So far novel coronavirus (CoV) outbreaks were associated with SARS-CoV-2 (2019), middle east respiratory syndrome coronavirus (MERS-CoV, 2012), and SARS-CoV-1 (2003) events. CoV relates to the enveloped family of Betacoronavirus (ßCoV) with positive-sense single-stranded RNA (+ssRNA). Knowing well the persistence, transmission, and spread of SARS-CoV-2 through proximity, the faecal-oral route is now emerging as a major environmental concern to community transmission. The replication and persistence of CoV in the gastrointestinal (GI) tract and shedding through stools is indicating a potential transmission route to the environment settings. Despite of the evidence, based on fewer reports on SARS-CoV-2 occurrence and persistence in wastewater/sewage/water, the transmission of the infective virus to the community is yet to be established. In this realm, this communication attempted to review the possible influx route of the enteric enveloped viral transmission in the environmental settings with reference to its occurrence, persistence, detection, and inactivation based on the published literature so far. The possibilities of airborne transmission through enteric virus-laden aerosols, environmental factors that may influence the viral transmission, and disinfection methods (conventional and emerging) as well as the inactivation mechanism with reference to the enveloped virus were reviewed. The need for wastewater epidemiology (WBE) studies for surveillance as well as for early warning signal was elaborated. This communication will provide a basis to understand the SARS-CoV-2 as well as other viruses in the context of the environmental engineering perspective to design effective strategies to counter the enteric virus transmission and also serves as a working paper for researchers, policy makers and regulators.

How much of antibiotics can enter surface water with treated wastewater and how it affects the resistance of waterborne bacteria: A case study of the Bialka river sewage treatment plant.

This study aimed to gain insight into the presence of antibiotics, occurrence of antimicrobial resistance and prevalence of extended-spectrum ß-lactamase (ESBL) genes in Escherichia coli in surface water, based on the example of the Bialka river, located in one of the most attractive tourist destinations in Poland. Water samples were collected in three sites: in the Tatra National Park (TNP), by the sewage discharge from the local treatment plant (STP) and c.a. 3 km downstream (DSTP). The analyses included determination of antibiotic content, enumeration of bacterial indicators of poor water quality, isolation and identification of Escherichia coli, which was subjected to antimicrobial susceptibility tests and assessment of ESBL-determining genes. Fourteen antimicrobials out of 24 tested were detected in river waters in varying concentrations. Trimethoprim and ofloxacin were most frequently detected. Most antibiotics were absent in the TNP, the highest numbers and the highest concentrations of antibiotics were observed by the STP discharge to decrease their content downstream. Culture-based tests of microbiological contamination showed similar results. Resistance to ampicillin was most frequent (64.5% strains), followed by cefazolin (50%). 20.6% of strains were ESBL-positive, while ESBL-determining gene, blaTEM was detected in 23.8% of E. coli strains. The largest percentage of antibiotic resistant and MDR E. coli strains was detected nearby the STP, indicating that malfunctioning STP may contribute largely to river water contamination downstream, also having significant environmental and economic impact.

Emerging contaminants in aquatic environments and coastal waters affected by urban wastewater discharge in Thailand: An ecological risk perspective.

Emerging contaminants such as synthetic musks and UV-filters as ingredients personal care products were widely used in human daily life in Thailand. The occurrence and fate of four synthetic musks and nine UV-filters were investigated in eight full-scale sewage treatment plants (STPs) and their receiving aquatic environments in Bangkok and Pattaya, Thailand. All target compounds were detected in every single sample from STPs and surface water with magnitude from ng/L to µg/L. HHCB-lactone and HMS were found as the predominant musk and UV filter in influent and effluent of STPs, respectively. HHCB-lactone was also found with the highest concentration up to 79501 ng/g (dw) in the sludge. Low removal efficiency range from -37% (HHCB-lactone) to 58% (AHTN) were found for four musks in the STPs. The total emission of Σ4musks and Σ9UV-filters were estimated to be up to 16.7 mg/person/day and 0.28 mg/person/day by the STPs. Three synthetic musks and seven UV-filters were detected in fish from the receiving river. Concentration and emission of musks and UV filters found in this study from Thailand were much higher than those reported in many other countries worldwide. The preliminary ecological risk assessment showed that Musk xylene, 4-MBC and OC may pose high risk to aquatic organisms in the riverine and estuarine environment in Thailand.

Spatial distribution of perfluoroalkyl acids (PFAAs) and their precursors and conversion of precursors in seawater deeply affected by a city in China.

Conversion of perfluoroalkyl acid (PFAA) precursors in the environment has been a hotspot research in recent years. This study firstly determined the spatial distribution of PFAAs and their precursors including 8:2 fluorotelomer unsaturated acid (8:2 FTUCA), perfluorooctane sulfoneamide (FOSA), and diperfluorooctane sulfonamido ethanol-based phosphate (di-SAmPAP), then investigated the conversion of the potential precursors in the seawater and sewage treatment plants (STPs) effluents. The results indicated that the target pollutants showed a typical concentration gradient from nearshore to offshore. And the obviously increased concentration of perfluorinated carboxylic acids (△[PFCAs]) after oxidation treatment can verify the existence of PFAA precursors in the seawater and STP effluents. The concentrations of PFCAs with carbon atom numbers 4-9 (PFCAC4-C9) revealed the most increase. Moreover, the levels of △[PFCAs] and the ratios of △[PFCAs] to their concentration before oxidation (△[PFCA]/[PFCA]before oxidation) indicated obvious spatial variations in the seawater and STP effluents. The higher levels of △[PFCAC4-C12] and the lower ratios of ∑△[PFCAC4-C12]/∑[PFAA]before oxidation were observed in the STP effluents, which implied that precursors might be decomposed during the sewage treatment process. These results suggested the STP effluents might have an important effect on the PFAAs levels of seawater.

Degradation mechanism of fipronil and its transformation products, matrix effects and toxicity during the solar/photo-Fenton process using ferric citrate complex.

This study presents the degradation of fipronil in sewage treatment plant (STP) effluent by photo-Fenton at near neutral pH (pH 6.0) using Fe3+/Citrate complex. 83% of fipronil degradation was reached using a molar iron/citrate ratio of 1:3 (192 µmol L-1 of Fe3+/576 µmol L-1 of citrate). Photo-Fenton reduced the toxicity of treated solutions as according to the survival of Drosophila melanogaster exposed to non-treated and treated samples. Control experiments performed in distilled water using 32 µmol L-1 of Fe3+/96 µmol L-1 of citrate achieved 98% of fipronil degradation within 100 kJ m-2 (UV-A radiation, k = 30 × 10-3 kJ-1 m2 and t1/2 = 23 kJ m-2), thus indicating that fipronil degradation is impaired by natural organic matter and inorganic ions present in STP effluent. Degradation was faster under solar radiation, as the same efficiency (98%) was obtained after 75 kJ m-2 (k = 63 × 10-3 kJ-1 m2 and t1/2 = 11 kJ m-2). In addition, pathways of fipronil degradation using Fe3+/Citrate under solar and UV-A radiation were investigated and transformation products proposed. Results revealed that the HO• attack occurred preferentially in the pyrazole ring. Eight transformation products were identified by UHPLC-Q-TOF-MS and four are unprecedented in the literature. Control experiments in distilled water demonstrated that toxicity reduction is related to fipronil degradation and that transformation products are less toxic than fipronil. Furthermore, toxicity of STP fortified with fipronil was reduced after photo-Fenton. These results demonstrate the feasibility of applying this process using Fe3+/Citrate complex for fipronil degradation in a real matrix.

Distribution and ecological risk of pharmaceuticals in surface water of the Yeongsan river, Republic of Korea.

This study examined the distribution of pharmaceuticals in Yeongsan River and at point sources (PSs) in the associated water system, and performed a risk assessment based on our findings. The samples included effluents collected from three sewage treatment plants (PS1, PS2, and PS3) and two industrial complexes (PS4 and PS5) as well as surface water collected from seven mainstreams and 11 tributaries of the river. The target pharmaceuticals were acetylsalicylic acid, carbamazepine, clarithromycin, naproxen, sulfamethazine, sulfamethoxazole, sulfathiazole, and trimethoprim, which were detected by liquid chromatography-tandem mass spectrometry. All pharmaceuticals except acetylsalicylic acid and sulfathiazole were found in PS1, PS2, and PS3 samples, whereas acetylsalicylic acid, carbamazepine, sulfamethazine, and sulfamethoxazole were found in PS4, most of the pharmaceuticals were not present in PS5. The rank order of pharmaceutical concentration in surface water was carbamazepine (97.2%, 0.2067 µg/L) > sulfamethoxazole (88.9%, 0.1132 µg/L) > naproxen (51.4%, 0.0516 µg/L) > clarithromycin (43.1%, 0.0427 µg/L). The distribution of pharmaceuticals in the Yeongsan River at PSs and non-PSs differed, and higher concentrations of human pharmaceuticals were detected in upstream and midstream areas whereas higher concentrations of animal pharmaceuticals were found downstream. Hazard quotients (HQs) evaluated at each sites based on mean concentration and 95% upper confidence limits (95% UCLs) were all less than one, indicating a low risk of toxicity. The findings of this study are expected to be useful for risk assessment of aquatic ecosystems.

Planning for achieving low carbon and integrated resources recovery from sewage treatment plants in Minas Gerais, Brazil.

There is an enormous deficit in sanitation infrastructure in most Brazilian cities. To tackle this challenge, it is crucial to conceive the new sanitation infrastructure based on sustainability principles, including an integrated approach for the management of the liquid, solid and gaseous phases. This study aimed at developing sustainable sewage treatment flowsheets for different scales and regional scenarios in the state of Minas Gerais. Two watersheds were chosen as study areas, due to their remarkable regional importance and socioeconomic and environmental diversity, i.e. Rio das Velhas and Jequitaí-Pacuí. Currently available processes for sewage treatment and resources recovery were assessed based on: literature review and benchmarking of operational practices, experiences reported by sanitation companies, techno-economic feasibility of resource recovery and carbon footprint assessment of anaerobic-based technologies. Social acceptance was also considered. A total of 15 sustainable flowsheets were proposed, comprising passive/natural systems (stabilization ponds, constructed wetlands and controlled land application), anaerobic process combined with natural systems (UASB reactors followed by controlled land application, constructed wetlands or polishing ponds) and compact anaerobic/aerobic systems (UASB reactors followed by activated sludge or trickling filters). Processes selected for small-scale sewage treatment plants (STPs) (people-equivalent - PE < 10,000 inhab.) intended to be integrated into local communities and economic activities. Large-scale STPs (especially those with PE > 100,000 inhab.) were conceived as industries, where a wide range of resources (e.g. sand for non-structural concrete, biogas for electricity, sludge for thermal energy) could be recovered from the influent sewage. Results obtained from the current study could serve as support for decision-making on the planning and implementation of new sustainable sanitation solutions in the state of Minas Gerais and possibly in other regions of Brazil and other developing countries.

Elimination of bacterial contaminations by treatment of water with boron-doped diamond electrodes.

Boron-doped diamond electrodes can be used to generate reactive oxygen species directly at the electrode's surface. This property was used in this study for in-situ electrochemical oxidation to eliminate different bacteria, i.e. Escherichia coli, Pseudomonas fluorescens and Pseudomonas aeruginosa, as well as Bacillus subtilis spores from water samples. Application of low voltages in the rage from 4 to 10 V and short incubation times in the range of minutes allowed a complete disinfection of water contaminated with enterobacteria and freshwater microbes including nosocomial pathogens as well as a significant reduction of spores. A pilot reactor was constructed, which allowed to decrease microbial contamination of sewage plant effluent drastically. Boron-doped diamond electrodes allow efficient reduction of bacterial contaminations in water samples.

Free-living bacteria and potential bacterial pathogens in sewage treatment plants.

To comprehensively understand the profile of free-living bacteria and potential bacterial pathogens in sewage treatment plants (STPs), this study applied high-throughput sequencing-based metagenomics approaches to investigate the effects of activated sludge (AS) treatment process and ultraviolet (UV) disinfection on the community of bacterial pathogens in two full-scale STPs. A total of 23 bacterial genera were identified as free-living bacteria, and 243 species/OTU97% were identified as potential bacterial pathogens, 6 of which were confidently detected in the STPs (with the total abundances ranging from 0.02 to 14.19%). Both diversity and relative abundance of the detected bacterial pathogens decreased obviously after AS treatment process (p < 0.05), and increased slightly after sedimentation (p < 0.05). UV disinfection shows no obvious effects on the total relative abundance of the free-living pathogenic bacteria in sewage. Although large amounts of the particle-bound pathogens were eliminated through the sewage treatment process, the STPs could not effectively remove the free-living bacterial pathogens, and some pathogenic bacteria (e.g., Pseudomonas aeruginosa) present in the effluent had higher relative abundance after UV disinfection. Overall, the results extend our knowledge regarding the community of potential pathogens (especially free-living pathogens) in STPs.

Evaluation of metal removal efficiency and its influence in the physicochemical parameters at two sewage treatment plants.

In sewage treatment plants, physicochemical parameters are highly controlled since treated sewage can be returned to water bodies or reused. In addition, pollutants such as heavy metals also deserve attention due to their potential toxicity. In general, these characteristics of sewage and treated water are evaluated independently, with the support of Brazilian legislation that does not require a routine for the analysis of metals as frequent as for the physicochemical parameters. In this work, 66 samples of raw sewage, treated sewage, and effluents from two treatment plants in the city of Bauru, São Paulo, Brazil, were evaluated to assess the efficiency of the treatment plants in the removal of metals. In addition, the influence of these pollutants on the quantification of physicochemical parameters was evaluated. The quantification of metals was performed using inductively coupled plasma optical spectroscopy (ICP-OES), and Spearman's test was applied to evaluate correlation between physicochemical parameters and metal content. The main metals found in the samples were Ba, Mn, Zn, Cu, Se, Fe, and Al. The results indicate that concentrations of metals in the aquatic environment can significantly affect the physicochemical parameters, since high concentrations of metals can interfere mainly in the pH, chemical oxygen demand, and dissolved oxygen.

Tessaracoccus defluvii sp. nov., isolated from an aeration tank of a sewage treatment plant.

A Gram-positive, non-motile, aerobic, coccus-shaped bacterium, designated strain LNB-140T, was isolated from a sewage treatment plant in the Republic of Korea and was characterised using a polyphasic taxonomic approach. Comparative 16S rRNA gene sequence analysis showed that strain LNB-140T belongs to genus Tessaracoccus in the family Propionibacteriaceae of the phylum Actinobacteria. The 16S rRNA gene sequence similarities between strain LNB-140T and type strains of the genus, Tessaracoccus flavescens SST-39T and Tessaracoccus rhinocerotis YIM101269T are 97.8 and 97.4 %, respectively. The chemotaxonomic properties of strain LNB-140T are consistent with those of members of the genus Tessaracoccus: a quinone system with MK-9(H4) as the predominant menaquinone; anteiso-C15:0 and iso C15:0 as the predominant cellular fatty acids; and LL-2,6-diaminopimelic acid as the diagnostic peptidoglycan diamino acid. The major polar lipids were identified as diphosphatidylglycerol and phosphatidylethanolamine. The G+C content of the genomic DNA was determined to be 67.1 mol%. Differential phenotypic properties along with low DNA-DNA relatedness (<30 ± 3.2 %) with closely related type strains show that strain LNB-140T is distinct from previously described members of the genus Tessaracoccus and represents a novel species in this genus, for which the name Tessaracoccus defluvii sp. nov. is proposed. The type strain is LNB-140T (=KEMB 5401-076T = JCM 17540T).