Urban Wastewater Treatment Plants Research Articles

Population-based variations of a core resistome revealed by urban sewage metagenome surveillance

Sewage-based surveillance is widely employed to understand the occurrence and distribution of antimicrobial resistance (AMR) in urban community. However, there are limited studies which investigated the sewage of different sources within community. The present study used metagenomics to decipher the AMR profiles in five sources: local residence’s source, animal source, migrant workers’ source, clinical source , and urban wastewater treatment plant influent. A core resistome of ARGs was found across all samples, accounting for 81.4%-93.3% of the abundance of total resistome with only 17.3% diversity, irrespective of the sewage sources. Clinically relevant ARGs were identified in the core resistome across all wastewater sources. This included genes conferring resistance to beta-lactams as biomarkers of hospital sewage. The pet center wastewater showed a high abundance of genes encoding resistance to tetracycline, which is a commonly used veterinary antibiotic. The resistome profile of sewage from the migrant workers’ dormitories showed a slight variation to that of the local residential population, suggesting possible differences in the human gut resistome of the foreign/migrant population, with biomarkers of genes encoding resistance to fosfomycin, fosmidomycin, kasugamycin, MLS, and polymyxin. The co-localization of ARGs and plasmid, MGEs and integrative and conjugative elements (ICEs) could explain variations in the core resistome, presumably a result of high antibiotic selection pressure. Further analysis showed a specific host-associated resistance pattern, in which core hosts mediated the core resistome profile. The core BMRGs were also co-localized with MGEs/ICEs and carried by core potential bacterial hosts. Local healthy population carried the lowest ARG load (copy number discharged by each person per day) but contributed the highest ARG burden (copy number discharged by the population). This study elucidates population-based variations of a core resistome, and further provides important insights into source tracking and management of AMR in urban environments.

Synergistic effect of sulfidated nanoscale zerovalent iron in donor and recipient bacterial inactivation and gene conjugative transfer inhibition

Antibiotic resistance genes (ARGs) and antibiotic resistant bacteria (ARB) are widespread in urban wastewater treatment plants (UWTPs). In this research, a horizontal transfer model of recipient (Pseudomonas. HLS-6) and donor (Escherichia coli DH5α carries RP4 plasmid) was constructed to explore the effect of sulfidated nanoscale zerovalent iron (S-nZVI) on the efficiency of plasmid-mediated horizontal transfer. When the S/Fe was 0.1, the inactivation efficiency of 1120 mg/L S-nZVI on the donor and recipient bacteria were 2.36 ± 0.03 log and 3.50 ± 0.17 log after 30 min, respectively (initial ARB concentration ≈ 5 ×107 CFU/mL). Effects of treatment time, S/Fe molar ratio, S-nZVI dosage and initial bacterial concentration were systemically studied. S-nZVI treatment could increase the extracellular alkaline phosphatase and malondialdehyde content of the ARB, cause oxidative stress in the bacteria, destroy the cell structure and damage the intracellular DNA. This study provided evidence and insights into possible underlying mechanisms for reducing conjugative transfer, such as hindering cell membrane repair, inducing the overproduction of reactive oxygen species, inhibiting the SOS response, reducing the expression of ARGs and related transfer genes. S-nZVI could inhibit the gene conjugative transfer while inactivating the ARB. The findings provided an alternative method for controlling antibiotic resistance.

Impact of nitrate addition on the resistome and mobilome from a full-scale sewer

Oxidative chemicals, such as nitrate, are periodically added to sewer systems to mitigate sulfide production and its accumulation but data are lacking on how these treatments affect sewage microbiota and alter their gene expression and mobilization. The present study investigated such effects on the biofilm of a full-scale sewer collected at two different locations, namely a pumping station and at the inlet of an urban wastewater treatment plant (WWTP), before and 15 days after nitrate dosage using a combination of culture-dependent and -independent approaches. Nitrate dosing resulted ineffective on the concentration of antibiotic-resistant Escherichia coli (AR-EC) in biofilms but greatly affected the composition of biofilm bacterial communities and the associated resistome and mobilome, especially at the pumping station where nitrate was dosed. Such responses consisted of a clear reduction on strict anaerobes; an almost twofold increase on the expression of recA gene (stress-response marker); and a significant increase on the relative abundance of most antibiotic resistance genes (ARGs) and mobile genetic elements (MGEs). In turn, the effects of nitrate dosing at the WWTP inlet were barely visible, suggesting that they vanished into the distance from the pumping site (2.4 km). Remarkably, however, the relative abundance of both resistance and mobilization gene biomarkers at the inlet of the studied WWTP clearly oversized that at the pumping station confirming that these facilities are sinks where these resistance determinants accumulate and propagate. Considering the abundance of resistant bacteria and genes in urban sewage, the effects of dosing chemicals should be carefully assessed to lessen the load of such biological pollutants into WWTPs.

Solar photo-Fenton at circumneutral pH using Fe(III)-EDDS compared to ozonation for tertiary treatment of urban wastewater: Contaminants of emerging concern removal and toxicity assessment

• Solar photo-Fenton compared to ozonation at pilot plant scale. • Successful CEC removal was achieved (>80%) but less treatment time was required by ozonation. • Acute and Chronic toxicity tests did not provide conclusive results. Solar photo-Fenton (SPF) at circumneutral pH with ethylenediamine-N,N'-disuccinic acid (EDDS) in raceway pond reactor was compared to a well-stablished process (ozonation) in the degradation of five contaminant of emerging concern (CECs, namely Caffeine, Carbamazepine, Diclofenac, Sulfamethoxazole and Trimethoprim) at the initial concentration of 100 μg/L each in urban wastewater treatment plant secondary effluent (UWWE) at pilot scale with natural sunlight. Both were found to be effective in the removal of the target CECs. Ozonation treatment was faster being able to degrade 80% of each CEC in UWWE within the early 15 min (18.0 mgO 3 /L consumed). Acute (using activated sludge, Vibrio fischeri and Daphnia magna) and chronic (using activated sludge at 72 h of sample contact and V. fischeri at 24 h of sample contact) toxicity were also evaluated. Acute toxicity evaluated by activated sludge did not show any toxic effect. V. fischeri gave less sensitive results compared to D. magna tests. Lower toxicity levels for SPF were observed. Highest acute toxicity was observed for D. magna in UWWE treated by ozonation. Relevant chronic toxicity assessed by activated sludge and V. fischeri was observed in almost all analysed samples, despite 80% of the CECs were eliminated. Successful performance of AOPs for CECs removal is not a guarantee of obtaining safe alternative water sources.

RECOMMENDATIONS FOR INCREASING THE EFFICIENCY OF WASTEWATER SLUDGE TREATMENT IN THE CITY OF BREST AT THE MECHANICAL AND BIOLOGICAL FACILITIES OF THE BREST WASTE PROCESSING PLANT (BWPP)

The implementation of technological schemes for the removal of biogenic elements at urban wastewater treatment plants requires an individual approach to the treatment of sludge. The article is devoted to the problems that arise during the treatment of urban sewage sludge at existing facilities for the treatment of sludge from primary settling tanks and excess activated sludge using flow type digesters. The latest developments in the field of aerobic and anaerobic digestion of sludge generated at urban wastewater treatment plants are also considered, which make it possible to make the process of sludge processing energy and resource-saving, as well as to ensure the purification of return flows from nitrogen compounds using the Anammox technology and the removal of phosphorus compounds with the production of mineral fertilizer - struvite. Information is also provided to compare the effectiveness of various regimes of reagentless pressure flotation with reagent sedimentation. The influence of temperature and compaction of sediments on the process of anaerobic digestion was analyzed. An improved technological scheme for the treatment of sludge coming from sewage treatment plants is proposed, which combines the processes of aerobic and anaerobic sludge digestion while maintaining optimal temperature and humidity.

Techno-Economic Evaluation of Ozone Application to Reduce Sludge Production in Small Urban WWTPs

In Chile, small wastewater treatment plants (WWTPs) (treatment capacity of less than 4,800 m3/d) are normally not designed with consideration for the potential valorization of generated sludge. For this reason, they are generally operated at high solids residence times (SRT) (15 d) to promote the decay of biomass, promoting less sludge production and reducing the costs associated with biomass management. Operation at high SRT implies the need for a larger activated sludge system, increasing capital costs. The implementation of a sludge-disintegration unit by ozonation in future WWTPs could enable operation at an SRT of 3 d, with low sludge generation. In this work, we evaluate how the implementation of a sludge-ozonation system in small WWTPs (200–4000 m3/d) would affect treatment costs. Four scenarios were studied: (1) a current WWTP operated at an SRT of 15 d, without a sludge ozonation system; (2) a WWTP operated at an SRT of 15 d, with a sludge-ozonation system that would achieve zero sludge production; (3) a WWTP operated at an SRT of 3 d, with a sludge-ozonation system that would provide the same sludge production as scenario 1; (4) a WWTP operated at an SRT of 15 d, with a sludge-ozonation system that would achieve zero sludge production. Economic analysis shows that the treatment costs for scenarios 1 and 2 are similar, while a reduction in cost of up to 47% is obtained for scenarios 3 and 4.

IncHI1A plasmids potentially facilitate horizontal flow of antibiotic resistance genes to pathogens in microbial communities of urban residential sewage.

Horizontal gene transfer via plasmids is important for the dissemination of antibiotic resistance genes among medically relevant pathogens. Specifically, the transfer of IncHI1A plasmids is believed to facilitate the spread of antibiotic resistance genes, such as carbapenemases, within the clinically important family Enterobacteriaceae. The microbial community of urban wastewater treatment plants has been shown to be highly permissive towards conjugal transfer of IncP1 plasmids. Here, we tracked the transfer of the P1 plasmid pB10 and the clinically relevant HI1A plasmid R27 in the microbial communities present in urban residential sewage entering full-scale wastewater treatment plants. We found that both plasmids readily transferred to these communities and that strains in the sewage were able to further disseminate them. Furthermore, R27has a broad potential host range, but a low host divergence. Interestingly, although the majority of R27 transfer events were to members of Enterobacteriaceae, we found a subset of transfer events to other families, even other phyla. This indicates that HI1A plasmids facilitate horizontal gene transfer both within Enterobacteriaceae, but also across families of, in particular, Gammaproteobacteria, such as Moraxellaceae, Pseudomonadaceae and Shewanellaceae. pB10 displayed a similar potential host range to R27. In contrast to R27, pB10had a high host divergence. By culture enrichment of the transconjugant communities, we show that sewage strains of Enterobacteriaceae and Aeromonadaceae can stably maintain R27 and pB10, respectively. Our results suggest that dissemination in the urban residual water system of HI1A plasmids may result in an accelerated acquisition of antibiotic resistance genes among pathogens.

Changes in Wastewater Treatment Performance and the Microbial Community during the Bioaugmentation of a Denitrifying Pseudomonas Strain in the Low Carbon–Nitrogen Ratio Sequencing Batch Reactor

The low carbon–nitrogen ratio (C/N) of influent wastewater results in the insufficient carbon source for the process of denitrification in urban wastewater treatment plants (WWTPs). A denitrifying bacterial strain, Pseudomonas sp. JMSTP, was isolated and demonstrated effective denitrification ability under a low C/N ratio of 1.5–4 (w/w) in anoxic conditions. Sequencing batch reactor (SBR) studies were conducted to test the bioaugmentation of JMSTP on total nitrogen (TN) removal under the influent COD/N ratio of 3/1. After the second bioaugmentation, the TN of effluent in the bioaugmented SBR was significantly lower than that in the control SBR. Redundancy analysis results showed that there was a positive correlation between Pseudomonas sp. abundance and TN removal in the bioaugmented SBR. Microbial community analysis showed that, especially after the second bioaugmentation, the abundance of Pseudomonas sp. decreased rapidly, but it was still much higher than that in the control SBR. Correlation network analysis showed that after the addition, Pseudomonas sp. had no significant co-occurrence relationship with other native bacteria, owing to the quick increase and decrease. Our results suggest that JMSTP shows the potential to enhance TN removal through bioaugmentation. Since the effect of bioaugmentation gradually diminishes, further research is still needed to investigate its long-lasting applications.

UVA LEDs and solar light photocatalytic oxidation/ozonation as a tertiary treatment using supported TiO2: With an eye on the photochemical properties of the secondary effluent

Photocatalytic oxidation/ozonation of a mixture of eight pharmaceuticals added to a secondary effluent, SE, of an urban wastewater treatment plant has been studied using TiO2 supported on commercial Al2O3/SiO2 ceramic foams. As radiation source UVA LEDs (365 nm) or solar radiation was used. Pharmaceuticals were added at high (1 mg L−1 each) or relatively low (50 μg L−1 each) concentration, contributing 25% and 1.5% to the initial TOC, respectively. Under both types of radiation, the photolysis of SE generated reactive species capable of degrading the contaminants (indirect photolysis), this effect being greater at lower initial concentration of pollutants. Lower concentration of contaminants also favoured their degradation and the SE mineralization by photocatalytic oxidation, whereas its effect on ozonation was low. The best results were obtained by photocatalytic ozonation, especially in terms of COD removal, without observing any synergism or antagonism between O3/Radiation and TiO2/Radiation systems. In SE, the performance of the supported catalyst resulted much better than that of suspended TiO2 P25, which showed almost no activity in this matrix. Through different cycles of reuse, the stability of the supported catalyst was confirmed.

Valorization of UWWTP effluents for ammonium recovery and MC elimination by advanced AOPs

The main objective of this study was to generate ready-to-use revalorized irrigation water for fertilization from urban wastewater treatment plant (UWWTP) effluents. The focus was on controlled retention of NH4+ and microcontaminants (MC), using nanofiltration. Retentates generated were treated by solar photo-Fenton at circumneutral pH using Ethylenediamine-N, N′-disuccinic acid (EDDS) iron complexing agent. Solar photo-Fenton degradation efficacy was compared with electrooxidation processes as anodic oxidation, solar-assisted anodic oxidation, electro-Fenton and solar photoelectro Fenton. Finally, phytotoxicity and acute toxicity tests were performed to demonstrate the potentially safe reuse of treated wastewater for crop irrigation. Nanofiltration was able to produce a ready-to-use permeate stream containing recovered NH4+. (valuable nutrient). Solar photo-Fenton treatment at circumneutral pH would only be of interest for rapid degradation of contaminants at less than 1 mg/L in nanofiltration retentates. Other alternative tertiary treatments, such as electrooxidation processes, are a promising alternative when a high concentration of MC requires longer process times. Anodic oxidation was demonstrated to be able to eliminate >80% of microcontaminants and solar-assisted anodic oxidation significantly reduced the electricity consumption. Electro-Fenton processes were the least efficient of the processes tested. Phytotoxicity results showed that irrigation with the permeates reduced germination, root development was mainly promoted and shoot development was positive only at low retention rate (concentration factor = 2). Acute and chronic Daphnia magna toxicity studies demonstrated that the permeate volumes should be diluted at least 50% before direct reuse for crop irrigation.

Tracking antibiotic resistance through the environment near a biosolid spreading ground: Resistome changes, distribution, and metal(loid) co-selection

The application of urban wastewater treatment plants (WWTPs) products to agricultural lands has contributed to the rising level of antibiotic resistance and drawn a critical public health concern. It has not been thoroughly investigated at which spatial scales a biosolid applied area as a potentially predominant source affects surrounding soil resistomes. This study investigated distribution and impact of WWTP biosolids treated with anaerobic digestion on an agricultural area. Heterotrophic plate counts (HPCs) and quantitative polymerase chain reaction (qPCR) were performed for detection of selected antibiotic-resistant bacteria (ARB), selected antibiotic resistance genes (ARGs), intI1 genes, and 16S rRNA genes. Biosolid samples contained significantly higher levels of selected ARGs than the raw agricultural soils (p < 0.05). The average relative abundances of intI1, sul1, blaSHV, and ermB genes were significantly higher in biosolid-amended soils than nearby agricultural soils (p < 0.05). Spatial interpolation analysis of relative gene abundances of intI1, sul1, sul2, and tetW across the studied area further indicated directional trends towards the northwest and southeast directions, highlighting possible airborne spread. Concentrations of Co, Cu, Ni, and Fe were found to be significantly and positively correlated with relative abundances of intI1, sul1, and tetW genes (p < 0.05). The resistance ratios of culturable antibiotic-resistant bacteria in agricultural soils with biosolid amendments were generally identical to those without biosolid amendments. This study will advance the understanding of the antibiotic resistome in agricultural soils impacted by long-term waste reuse and inform the evaluation strategies for future biosolids application and management.

PET particles raise microbiological concerns for human health while tyre wear microplastic particles potentially affect ecosystem services in waters

Although abundant and chemically peculiar, tyre wear microplastic particles (TWP) and their impact on the microbial communities in water are largely understudied. We tested in laboratory based semi-continuous cultures the impact of TWP and of polyethylene terephthalate (PET) derived particles (following a gradient of relative abundance) on the pathobiome (the group of potential human pathogenic bacteria) of a freshwater microbial community exposed to contamination by the effluent of a urban wastewater treatment plant, for a period of 28 days. We could define the modulated impact of the two types of microplastic particles: while PET does not favour bacterial growth, it offers a refuge to several potential pathogens of allochthonous origin (from the treated sewage effluent), TWP act as an additional carbon source, promoting the development and the massive growth of a biofilm composed by fast-growing bacterial genera including species potentially harmful and competitive in abating biodiversity in surface waters. Our results demonstrate the different ecological role and impact on freshwater environments of TWP and PET particles, and the need to approach the study of this pollutant not as a whole, but considering the origin and the chemical composition of the different particles.

Understanding the bioaccumulation of pharmaceutical active compounds by clams Ruditapes decussatus exposed to a UWWTP discharge

Twenty-four pharmaceutical active compounds (PhACs) were evaluated in the soft tissues of clams Ruditappes decussatus exposed along a 1.5-km dispersal gradient of the treated effluent from an urban wastewater treatment plant discharging in Ria Formosa, and compared with those in the marine waters and discharged effluents. The clams were exposed for 1 month, in June–July 2016, 2017 and 2018. PhACs were quantified by high performance liquid chromatography coupled to tandem mass spectrometry after the quick, easy, cheap, effective, rugged and safe (QuEChERS) method (clams) or solid-phase extraction (water samples). The most representative PhACs in the effluents and receiving waters (regardless of the tidal dilution effect) were diclofenac, carbamazepine and caffeine (on average ≤ 2 μg/L) and only caffeine exhibited significant inter-annual differences, with higher values in 2017. In turn, the most bioaccumulated PhACs in clams were caffeine (0.54–27 ng/g wet weight, significantly higher in 2016) and acetaminophen (0.37–3.7 ng/g wet weight, significant lower in 2016). A multivariate principal component analysis showed (i) PhAC bioaccumulation primarily depended on biotic factors (clams length and weight), (ii) PhAC physicochemical properties Log Kow, pKa and water solubility interplaying with water abiotic variables were more relevant for explaining data variability in water than the physical dilution/tidal mixing, (iii) this process, reflected by the salinity gradient, had a tertiary role in data variation, responsible for spatial discrimination of marine waters. This study provides a better understanding of PhACs bioaccumulation by clams Ruditapes decussatus in real environmental conditions, under the influence of urban treated effluent dispersal in Ria Formosa coastal lagoon, a major producer of bivalves, ultimately disentangling key factors of PhAC bioaccumulation.

Tracking Cryptosporidium in urban wastewater treatment plants in a cold region: Occurrence, species and infectivity

Tracking Cryptosporidium in urban wastewater treatment plants in a cold region: Occurrence, species and infectivity

Longitudinal Chemical Gradients and the Functional Responses of Nutrients, Organic Matter, and Other Parameters to the Land Use Pattern and Monsoon Intensity

River water quality degradation is one of the hottest environmental issues worldwide. Therefore, monitoring water quality longitudinally and temporally is crucial for effective water management and contamination control. The main aim of this study was to assess the longitudinal variations in water quality in the mainstream of the Han River, Korea, from 2015 to 2019. The trophic state classification (TSC), microbial pollution indicator (MPI), and river pollution index (RPI) were calculated to characterize river water quality and revealed more serious pollution toward the downstream zone (Dz) due to agricultural and urban-dominated areas. The biodegradability index (BI) indicated that non-biodegradable organic pollutants are increasing in the water body from the urban and animal wastewater treatment plants. Nutrients, organic matter contents, total suspended solids, ionic factors, and algal chlorophyll were higher in the Dz than in any other zones and were markedly influenced by the summer monsoon. Empirical analysis showed that nutrients and organic matter had positive linear functional relations with agricultural and urban coverage and negative linear relations with forest coverage. The pollutant-transport function suggested that suspended solids act as TP and TN carriers. Regression analysis indicated that TP (R2 = 0.47) has more positive functional relations with algal growth than TN (R2 = 0.22). Our findings suggest that a combination of empirical models and pollution indices might be utilized to assess river water quality and that the resulting information could aid policymakers in managing the Han River.

Occurrence and fate of poly- and perfluoroalkyl substances (PFAS) in urban waters of New Zealand

Information on the occurrence of PFAS in aquatic matrices of countries with no PFAS manufacturing, e.g., New Zealand, is limited. Also, the fingerprint of PFAS along an urban water cycle, following water path from wastewater treatment plant (WWTP) effluent to treated drinking water has not been widely assessed. Hence, 38 long-, short-, ultrashort-chain PFAS and fluorinated alternatives (including precursors) were monitored in this study by collecting composite samples from two urban WWTPs of New Zealand and grab samples from the water bodies receiving the WWTPs’ effluents and a drinking water treatment plant, whose source water received the effluent of one of the studied WWTPs. ∑PFAS at concentrations 0.1 – 13 ng/L were detected in all wastewater samples, including influents and different treatment stages of the two WWTPs (WW1 and WW2). The fate of most PFAS was similar in the two WWTPs, despite large differences in WWTPs’ PFAS loads in the influents, serving populations (1.6 vs 0.16 million), total capacities (300 vs 54 million liters per day), and designs (aerobic and anoxic secondary treatment vs aerobic only). The fate of PFAS in WWTPs appeared to be driven by a range of processes. For instance, a simultaneous increase (41.6%) in short-chain perfluorohexanoic acid (PFHxA) concentrations and decrease (49.7%) in precursor 6:2 fluorotelomer sulfonate (6:2 FTS) concentrations after secondary biological treatment suggested possible transformation of 6:2 FTS into PFHxA during the treatment. In contrast, the reason behind an average decrease of 35% in ultrashort-chain perfluoropropionic acid (PFPrA) concentrations after treatment was unclear, and further studies are recommended. The concentrations of a linear isomer of long-chain perfluorosulfonic acid (PFOS-L) decreased (48%) in the effluent, possibly due to its partitioning to sludge. Although the concentrations of PFAS in coastal waters suggested that the WW1 effluent is a potential source of PFAS, earlier dispersion model and no detection of PFAS in the receiving waters of WW2 implied that other sources, such as septic systems, peripheral industries, and the airport, could also be contributing to PFAS in coastal waters. The source of ultrashort-chain PFPrA (5.5 ng/L) detected in the treated drinking water produced from that river was unclear. The monitoring results confirm incomplete removal of PFAS in WWTPs, indicate a possible transformation of unknown precursors present in wastewater into short-chain perfluoroalkylcarboxylic acids (PFCAs) during biological treatment, and reveal a possible accumulation of perfluoroalkylsulfonic acids (PFSAs) in the sludge, overall suggesting the circulation of PFAS in urban water systems.

Discrimination and surveillance of infectious severe acute respiratory syndrome Coronavirus 2 in wastewater using cell culture and RT-qPCR

Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) RNA has been extensively detected in raw wastewater in studies exploring wastewater-based epidemiology (WBE) for early warning purposes. Nonetheless, only a few limited studies investigated the presence of SARS-CoV-2 in treated wastewaters to determine the potential health risks across the water cycle. The detection of SARS-CoV-2 has been done mostly by RT-qPCR and ddPCR, which only provides information on the presence of nucleic acids rather than information on potential infectivity. In this study, we set to develop and evaluate the use of viability RT-qPCR for the selective discrimination and surveillance of infectious SARS-CoV-2 in secondary-treated wastewater. Enzymatic (nuclease) and viability dye (Reagent D) pretreatments were applied to infer infectivity through RT-qPCR using porcine epidemic diarrhea virus (PEDV) as a CoV surrogate. Infectivity tests were first performed on PEDV purified RNA, then on infectious and heat-inactivated PEDV, and finally on heat inactivated PEDV spiked in concentrated secondary-treated wastewater. The two viability RT-qPCR methods were then applied to 27 secondary-treated wastewater samples positive for SARS-CoV-2 RNA at the outlet of five large urban wastewater treatment plants in Portugal. Reagent D pretreatment showed similar behavior to cell culture for heat-inactivated PEDV and both viability RT-qPCR methods performed comparably to VERO E6 cell culture for SARS-CoV-2 present in secondary-treated wastewater, eliminating completely the RT-qPCR signal. Our study demonstrated the lack of infectious SARS-CoV-2 viral particles on secondary-treated wastewater through the application of two pretreatment methods for the rapid inference of infectivity through RT-qPCR, showing their potential application in environmental screening. This study addressed a knowledge gap on the public health risks of SARS-CoV-2 across the water cycle.

Pharmaceutical residues in digested sewage sludge: Occurrence, seasonal variation and risk assessment for soil

The occurrences, temporal variations and ecotoxicological risks of 38 selected pharmaceuticals from 7 therapeutic classes (i.e. antibiotics, analgesics, anti-inflammatories, beta-blockers, lipid regulators, anticancer agents, and psychiatric drugs) have been observed in the anaerobically treated sludge of the urban wastewater treatment plant (WWTP) in Konya, Turkey. Sampling was carried out to assess the seasonal variations in one year. The total daily wastewater flow rate of the WWTP was approximately 200,000 m3/day, and 140 tons/day of treated sludge were produced. The total concentrations of all pharmaceutical compounds ranged from 280 to 4898 μg/kg of dry matter (dm). The dominant therapeutic class was analgesics and anti-inflammatories (49%), which was followed by antibiotics (31%). Clarithromycin and azithromycin were the most abundant compounds, with concentrations of 1496 μg/kg dm. The total daily pharmaceutical load in the treated sludge was as high as 1.002 kg/day in the winter season, while the annual pharmaceutical mass load that was discharged into the environment was estimated to be approximately 71.6 kg. The use of treated sludge as fertilizer in agricultural lands causes continuous contamination of the terrestrial environment by pharmaceuticals. Five antibiotics (i.e., azithromycin, clarithromycin, erythromycin, sulfamethoxazole, and doxycycline), one analgesic (acetylsalicylic acid) and one beta-blocker (atenolol) in the digested sludge pose acute and short chronic high risks to environment. The highest short chronic risk in the digested sludge-amended soils was determined for azithromycin (RQ: 54.9). To reduce the potential environmental impact of pharmaceuticals, digested sludge should be monitored in terms of the pharmaceutical contents before being applied to soil.

Recovery of Ammonia from Centrate Water in Urban Waste Water Treatment Plants Via Direct Contact Membrane Distillation: Process Performance in Long-Term Pilot-Scale Operation

Recovery of Ammonia from Centrate Water in Urban Waste Water Treatment Plants Via Direct Contact Membrane Distillation: Process Performance in Long-Term Pilot-Scale Operation

The use of soil based on sewage sludge from urban wastewater treatment plants in the greening of urban areas

The use of soil based on sewage sludge from urban wastewater treatment plants in the greening of urban areas