Large Wastewater Treatment Plant Research Articles

Impact of reduced sampling frequency of illicit drug wastewater monitoring in the Netherlands

Drug consumption estimates are traditionally based on surveys or information from police seizures. Alternatively, residues of illicit drugs in untreated wastewater (influent) can be used to calculate mass loads and subsequently estimate drug consumption in the community throughout the week. For this purpose, wastewater is commonly sampled for seven consecutive days within the Sewage analysis CORe group Europe (SCORE), while other sampling schemes may be implemented in long-term studies outside this consortium. The current study demonstrates how sampling frequency of illicit drug residues in the influent of wastewater treatment plants (WWTPs) affects the derived weekly average. Thirty WWTPs were sampled over the course of 12 years and influents were analyzed for five drugs (metabolites): 3,4-methylenedioxymethamphetamine (MDMA), methamphetamine, amphetamine, benzoylecgonine (a metabolite of cocaine), and 11-nor-9-Carboxy tetrahydrocannabinol (THC-COOH). Subsequently, small and large WWTPs were grouped with a threshold of 100,000 inhabitants. After data curation, standardized loads were calculated (mg/d per 1000 inhabitants). Weekly averages of loads of the drug residues were calculated based on six scenarios (sampling one to six weekdays) and compared to the weekly average in the control situation (sampling seven weekdays) in a Monte Carlo simulation. Results indicate that drug residues with more dynamic loads over a week require more frequent sampling. The analysis illustrates that a decreased sampling frequency (4 or 5 days per week) still leads to a representative weekly average for all drugs tested when a deviation up to a factor of 1.25 is deemed acceptable. However, knowledge on typical levels is necessary to define outliers. We therefore recommend to study dynamics in drug residue loads for WWTPs before reducing sampling frequency in long term monitoring programs.

Simultaneous biomass concentration and subsequent quantitation of multiple infectious disease agents and antimicrobial resistance genes from community wastewater

Wastewater-based surveillance (WBS) of infectious disease agents is increasingly seen as a reliable source of population health data. To date, wastewater-based surveillance efforts have largely focused on individual pathogens. However, given that wastewater contains a broad range of pathogens circulating in the population, a more comprehensive approach could enhance its usability. We focused on the simultaneous detection of SARS-CoV-2, sapovirus, Campylobacter jejuni, Campylobacter coli, Salmonella spp., pathogenic Escherichia coli, Cryptosporidium spp., Giardia spp. and antimicrobial resistance genes (ARGs) of clinical relevance. To achieve this goal, biomass concentration and nucleic acid extraction methods were optimized, and samples were analyzed by using a set of (RT)-qPCR and (HT)-qPCR methods. We determined the prevalence and the spatial and temporal trends of the targeted pathogens and collected novel information on ARGs in Finnish wastewater. In addition, the use of different wastewater concentrates, namely the ultrafiltered concentrate of the supernatant and the centrifuged pellet, and the effect of freezing and thawing wastewater prior to sample processing were investigated with the indicator microbe crAssphage. Freeze-thawing of wastewater decreased the gene copy count of crAssphage in comparison to analyzing fresh samples (p < 0.001). Campylobacters were most abundant in two of the four studied summer months (30 % detection rate) and in wastewaters from regions with intensive animal farming. Salmonella, however, was detected in 40 % of the samples without any clear seasonal trends, and the highest gene copy numbers were recorded from the largest wastewater treatment plants. Beta-lactamase resistance genes that have commonly been detected in bacteria isolated from humans in Finland, namely blaCTX-M, blaOXA48, blaNDM, and blaKPC, were also frequently detected in wastewaters (100, 98, 98, and 70 % detection rates, respectively). These results confirm the reliability of using wastewater in public health surveillance and demonstrate the possibility to simultaneously perform WBS of multiple pathogens.

Impact of Design and Mixing Strategies on Biogas Production in Anaerobic Digesters

Anaerobic digestion (AD) is a biological process that breaks down organic matter in the absence of oxygen, producing biogas and nutrient-rich digestate. Various reactor designs and mixing strategies are well-established in AD processes, each with their own advantages and benefits. The presented study summarizes and investigates the state of the art of AD in domestic wastewater treatment plants (WWTPs) in an Austrian alpine region, with a primary focus on finding similarities among the most efficient plants regarding digester design, mixing approaches, and biogas production. By combining surveys and detailed field studies in cooperation with 34 WWTPs, the study provides a comprehensive overview of common AD practices, reactor shapes, and inherent mixing methods, highlighting their potential regarding energetic efficiency and biogas production. The results of the survey reveal qualitative trends in efficient AD design alongside detailed quantitative data derived from the supervised in-field optimization studies. Notably, one of the studies demonstrated energetic savings of 52% with no decrease in biogas production, achieved by transitioning from gas injection to mechanical agitation. Redundant impeller-based overmixing was also practically investigated and demonstrated in another field study. After optimization, the adaptations also resulted in energy savings of 30%, still proving sufficient substrate mixing with biomethane potential analysis. In conclusion, this research emphasizes the economic and environmental importance of energy-refined practices and optimized processes while highlighting the sustainability of AD, particularly for large domestic WWTPs but also for different comparable applications.

Occurrence and analysis of microplastics in municipal wastewater, Poland

Microplastics are a growing environmental threat and wastewater treatment plants have been identified as significant conduits for these pollutants. This study addresses microplastic loading in the influent of a large urban wastewater treatment plant, presenting a detailed analysis of their prevalence and characteristics. Our findings reveal a concentration of 4.09 microplastic particles per litre in the tributary. We performed a detailed statistical comparison of the microplastic particles, categorising them by shape, size, colour, and polymer type. Using Fourier transform total reflectance infrared spectroscopy, we identified 13 different polymer types, with polyethylene terephthalate, rubber, and polyethylene predominating. The analysis showed that textile fibres, mainly from clothing, are the most prevalent form of microplastic in wastewater, followed by fragments from the breakdown of larger plastic objects and films. This research highlights the critical need for strategic interventions to mitigate microplastic pollution at municipal sources.

The role of microalgae in effective instream agricultural wastewater treatment

ABSTRACT The Egyptian water crisis has encouraged the exploration of innovative solutions for wastewater treatment. One promising approach is using treated agricultural drainage water for its large amount per year and low pollution. There are many methods used for the treatment of wastewater, but this research focused on a new one which is the use of microalgae for in-situ treatment of wastewater, due to its ability to uptake and adsorb pollutants, aerate water, and produce biomass for potential use as a biofuel or fertilizer. Microalgae have shown great potential for removing various pollutants from wastewater, including organic matter, nutrients, heavy metals, and pathogens. Moreover, the use of microalgae for wastewater treatment can be more cost-effective and sustainable than traditional wastewater treatment methods, which often require large and expensive infrastructure. This study aimed to investigate the effectiveness of using microalgae for in-situ treatment of agricultural drainage wastewater of Bahr El-Baqar drain. The results revealed that the removal efficiencies were 29% for BOD (biochemical oxygen demand), 46.9% for COD (chemical oxygen demand), 56.1% for TSS (total suspended solids), 31% for HM (Heavy Metal) removal, and 86% increment in DO (Dissolved Oxygen) concentration. This experiment provided evidence that microalgae could be a promising and cost-effective solution for in-situ treatment of agricultural drainage wastewater, with high removal efficiencies for pollutants in wastewater and the potential to reduce the need for constructing large and expensive wastewater treatment plants.

Metagenomic Investigation of the Short-Term Temporal and Spatial Dynamics of the Bacterial Microbiome and the Resistome Downstream of a Wastewater Treatment Plant in the Iskar River in Bulgaria.

Waste Water Treatment Plants (WWTP) aim to reduce contamination in effluent water; however, studies indicate antimicrobial resistance genes (ARGs) persist post-treatment, potentially leading to their spread from human populated areas into the environment. This study evaluated the impact of a large WWTP serving 125,000 people on the Iskar River in Bulgaria, by characterizing the spatial and short-term temporal dynamics in bacterial community dynamics and resistance profiles of the surface water. Pairs of samples were collected biweekly on four dates from two different locations, one about 800 m after the WWTP effluents and the other 10 km downstream. Taxonomic classification revealed the dominance of Pseudomonodota and Bacteriodota, notably the genera Flavobacterium, Aquirufa, Acidovorax, Polynucleobacter, and Limnohabitans. The taxonomic structure corresponded with both lentic and lotic freshwater habitats, with Flavobacterium exhibiting a significant decrease over the study period. Principal Coordinate Analysis revealed statistically significant differences in bacterial community composition between samples collected on different dates. Differential abundance analysis identified notable enrichment of Polynucleobacter and Limnohabitans. There were shifts within the enriched or depleted bacterial taxa between early and late sampling dates. High relative abundance of the genes erm(B), erm(F), mph(E), msr(E) (macrolides); tet(C), tet(O), tet(W), tet(Q) and tet(X) (tetracyclines); sul1 and sul2 (sulphonamides); and cfxA3, cfxA6 (beta-lactams) were detected, with trends of increased presence in the latest sampling dates and in the location closer to the WWTP. Of note, genes conferring resistance to carbapenems blaOXA-58 and blaIMP-33-like were identified. Co-occurrence analysis of ARGs and mobile genetic elements on putative plasmids showed few instances, and the estimated human health risk score (0.19) according to MetaCompare2.0 was low. In total, 29 metagenome-assembled genomes were recovered, with only a few harbouring ARGs. This study enhances our understanding of freshwater microbial community dynamics and antibiotic resistance profiles, highlighting the need for continued ARGs monitoring.

Chemical-Saving Potential for Membrane Bioreactor (MBR) Processes Based on Long-Term Pilot Trials.

Membrane bioreactors (MBRs) have gained attraction in municipal wastewater treatment because of their capacity to meet strict water quality standards and support water reuse. Despite this, their operational sustainability is often compromised by high resource consumption, especially regarding the use of chemicals for membrane cleaning. This study explores innovative membrane-cleaning strategies to enhance the sustainability of MBR processes. Through long-term pilot trials at Stockholm's largest wastewater treatment plant, this study showed that alternative cleaning strategies can reduce chemical use by up to 75% without sacrificing treatment performance. The results further suggest that these alternative strategies could result in cost reductions of up to 70% and a reduction in environmental impacts by as much as 95% for certain indicators. Given that MBRs play a crucial role in addressing increasing treatment demands and advancing circular water management, the outcomes of this study are beneficial for the broader adoption of MBR processes. These results also have implications for existing installations, offering a pathway to more sustainable wastewater treatment. Moreover, the presented cleaning strategies provide significant opportunities for lowering operational costs and reducing the environmental footprint of new and existing MBR installations.

Leveraging wastewater: Validating the national-scale SARS-CoV-2 surveillance system in Cyprus for elevated public health surveillance and enhanced epidemiological insight

The validation of a cross-country, national-scale SARS-CoV-2 wastewater surveillance system for the monitoring of public health in the Republic of Cyprus, took place during October 2021-September 2022. The chronicle of SARS-CoV-2 genetic marker concentrations and prevailing Variants of Concern (VoCs) in all large Wastewater Treatment Plants (WWTPs) of Cyprus for a continuous period of 1 year, was recorded through an integrated, multi-disciplinary sewage-based surveillance system set up to track, visualize and make the collected information and statistical analysis outcomes, publicly available. Composite sampling and physicochemical parameter normalization of Population Equivalents (PE) and SARS-CoV-2 genetic marker concentration loads were utilized.Chemical Oxygen Demand (COD) was selected for normalization of genetic fragment loads. The selection of a normalization method should be tailored according to the characteristics of each individual city/WWTP population structure, flows and wastewater origin. Metagenomic sequencing showed the transition of the SARS-CoV-2 genome from the Delta to the Omicron variant prevalence, in agreement with changes in wastewater gene concentrations. Differences in the early detection of SARS-CoV-2 genetic markers were found among cities. The established system was able to track and monitor the trend of SARS-CoV-2, even in times of absence of other public health measures such as tracing of confirmed COVID-19 cases, showing the capacity of the wastewater system to quickly capture shifts in infections.The work done herein, confirmed the ability of the national-scale system to timely observe pandemic trends, evaluate effects of control measures implemented and monitor the burden of infected patients that shed SARS-CoV-2 fragments.

Treating wastewater for microplastics to a level on par with nearby marine waters

Retention of microplastics (MPs) at the third largest wastewater treatment plant (WWTP) in Sweden was investigated. The plant is one of the most modern and advanced of its kind, with rapid sand filter for tertiary treatment in combination with mechanical, biological, and chemical treatment. It achieved a significantly high treatment efficiency, which brought the MP concentration in its discharge on par with concentrations measured in marine waters of the same region. This novel data shows that properly designed modern WWTPs can reduce the MP content of sewage down to background levels measured in the receiving aquatic environment. Opposite to current understanding of the retention of MP by WWTPs, a modern and well-designed WWTP does not have to be a significant point source for MP. MPs were quantified at all major treatment steps, including digester inlet and outlet sludge. MPs sized 10–500 µm were analyzed by a focal plane array based micro-Fourier transform infrared (FPA-µFTIR) microscopy, a hyperspectral imaging technique, while MPs above 500 µm were analyzed by Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) spectroscopy. Mass was estimated from the hyperspectral images for MPs <500 µm and from microscope images >500 µm. The overall treatment efficiency was in terms of MP counts 99.98 %, with a daily input of 6.42 × 1010 and output of 1.04 × 107 particles. The mass removal efficiency was 99.99 %. The mechanical part of the treatment, the pre-treatment, and primary stages, reduced both the MP counts and mass by approximately 71 %. The combined biological treatment, secondary settling, and final polishing with rapid sand filtration removed nearly all the remaining 29 %. MPs became successively smaller as they passed the different treatment steps. The digester inlet received 1.04 × 1011 MPs daily, while it discharged 9.96 × 1010 MPs, causing a small but not significant decrease in MP counts, with a corresponding MP mass reduction of 9.56 %.

Biochar from recovered cellulose as new admixture in constructed wetlands for micropollutant removal: A circular approach

This study aimed to evaluate the suitability of biochar produced by pyrolysis from recovered wastewater cellulose and activated biologically as an admixture in Constructed Wetlands (CWs) when applied as a post-treatment step to remove micropollutants (MPs) from municipal wastewater effluent. Two planted vertical flow mesocosm CWs with cellulose-based admixtures of different origins (plant residue and recovered toilet paper) were fed with a municipal wastewater effluent representative for rural catchments. The results showed an average MPs elimination of 89.1 % for the activated biochar produced from recovered cellulose when 15 relevant compounds are considered and a reduction of the risk from compounds cocktail below the maximum acceptable level having diclofenac, carbamazepine, PFOS, ciprofloxacin and clarithromycin as main risk drivers (Risk Quotient > 1). The implementation of a circular approach to reduce MPs was finally conducted for the Blies catchment (Saarland region in Germany) characterized by low population density and small, sensitive water bodies. This approach demonstrates the feasibility of combining cellulose recovery with a fine sieve in large wastewater treatment plants (WWTPs) and providing biochar produced from recovered cellulose as an admixture to small WWTP where CW is an affordable solution for MP mitigation.

Using the fish plasma model to evaluate potential effects of pharmaceuticals in effluent from a large urban wastewater treatment plant

Several pharmaceuticals and personal care products (PPCPs) were evaluated using the fish plasma model (FPM) for juvenile Chinook salmon exposed to effluent from a large urban wastewater treatment plant. The FPM compares fish plasma concentrations to therapeutic values determined in human plasma as an indication of potential adverse effects. We used human Cmax values, which are the maximum plasma concentration for a minimum therapeutic dose. Observed and predicted plasma concentrations from juvenile Chinook salmon exposed to a dilution series of whole wastewater effluent were compared to 1%Cmax values to determine Response Ratios (RR) ([plasma]/1%Cmax) for assessment of possible adverse effects. Several PPCPs were found to approach or exceed an RR of 1, indicating potential effects in fish. We also predicted plasma concentrations from measured water concentrations and determined that several of the values were close to or below the analytical reporting limit (RL) indicating potential plasma concentrations for a large number of PPCPs that were below detection. Additionally, the 1%Cmax was less than the RL for several analytes, which could impede predictions of possible effect concentrations. A comparison of observed and predicted plasma concentrations found that observed values were frequently much higher than values predicted with water concentrations, especially for low log10Dow compounds. The observed versus predicted values using the human volume of distribution (Vd), were generally much closer in agreement. These data appear to support the selection of whole-body concentrations to predict plasma values, which relies more on estimating simple partitioning within the fish instead of uptake via water. Overall, these observations highlight the frequently underestimated predicted plasma concentrations and potential to cause adverse effects in fish. Using measured plasma concentrations or predicted values from whole-body concentrations along with improved prediction models and reductions in analytical detection limits will foster more accurate risk assessments of pharmaceutical exposure for fish.

A holistic approach for performance evaluation of wastewater treatment plants: integrating grey water footprint and life cycle impact assessment.

Wastewater treatment plants (WWTPs) have positive and negative impacts on the environment. Therefore, life cycle impact assessment (LCIA) can provide a more holistic framework for performance evaluation than the conventional approach. This study added water footprint (WF) to LCIA and defined ϕ index for accounting for the damage ratio of carbon footprint (CF) to WF. The application of these innovations was verified by comparing the performance of 26 WWTPs. These facilities are located in four different climates in Iran, serve between 1,900 and 980,000 people, and have treatment units like activated sludge, aerated lagoon, and stabilization pond. Here, grey water footprint (GWF) calculated the ecological impacts through typical pollutants. Blue water footprint (BWF) included the productive impacts of wastewater reuse, and CF estimated CO2 emissions from WWTPs. Results showed that GWF was the leading factor. ϕ was 4-7.5% and the average WF of WWTPs was 0.6 m3/ca, which reduced 84%, to 0.1 m³/ca, through wastewater reuse. Here, wastewater treatment and reuse in larger WWTPs, particularly with activated sludge had lower cumulative impacts. Since this method takes more items than the conventional approach, it is recommended for integrated evaluation of WWTPs, mainly in areas where the water-energy nexus is a paradigm for sustainable development.

Metagenomic insights into the wastewater resistome before and after purification at large‑scale wastewater treatment plants in the Moscow city

Wastewater treatment plants (WWTPs) are considered to be hotspots for the spread of antibiotic resistance genes (ARGs). We performed a metagenomic analysis of the raw wastewater, activated sludge and treated wastewater from two large WWTPs responsible for the treatment of urban wastewater in Moscow, Russia. In untreated wastewater, several hundred ARGs that could confer resistance to most commonly used classes of antibiotics were found. WWTPs employed a nitrification/denitrification or an anaerobic/anoxic/oxic process and enabled efficient removal of organic matter, nitrogen and phosphorus, as well as fecal microbiota. The resistome constituted about 0.05% of the whole metagenome, and after water treatment its share decreased by 3–4 times. The resistomes were dominated by ARGs encoding resistance to beta-lactams, macrolides, aminoglycosides, tetracyclines, quaternary ammonium compounds, and sulfonamides. ARGs for macrolides and tetracyclines were removed more efficiently than beta-lactamases, especially ampC, the most abundant ARG in the treated effluent. The removal efficiency of particular ARGs was impacted by the treatment technology. Metagenome-assembled genomes of multidrug-resistant strains were assembled both for the influent and the treated effluent. Ccomparison of resistomes from WWTPs in Moscow and around the world suggested that the abundance and content of ARGs depend on social, economic, medical, and environmental factors.

Enhancing compound confidence in suspect and non-target screening through machine learning-based retention time prediction

The retention time (RT) of contaminants of emerging concern (CECs) in liquid chromatography-high-resolution mass spectrometry (LC-HRMS) is crucial for database matching in non-targeted screening (NTS) analysis. In this study, we developed a machine learning (ML) model to predict RTs of CECs in NTS analysis. Using 1051 CEC standards, we evaluated Random Forest (RF), XGBoost, Support Vector Regression (SVR), and Artificial Neural Network (ANN) with molecular fingerprints and chemical descriptors to establish an optimal model. The SVR model utilizing chemical descriptors resulted in good predictive capacity with R2ext = 0.850 and r2 = 0.925. The model was further validated through laboratory NTS compound characterization. When applied to examine CEC occurrence in a large wastewater treatment plant, we identified 40 level S1 CECs (confirmed structure by reference standard) and 234 level S2 compounds (probable structure by library spectrum match). The model predicted RTs for level S2 compounds, leading to the classification of 153 level S2 compounds with high confidence (ΔRT <2 min). The model served as a robust filtering mechanism within the analytical framework. This study emphasizes the importance of predicted RTs in NTS analysis and highlights the potential of prediction models. Our research introduces a workflow that enhances NTS analysis by utilizing RT prediction models to determine compound confidence levels.

Using Surrogate Parameters to Enhance Monitoring of Community Wastewater Management System Performance for Sustainable Operations.

Community wastewater management systems (CWMS) are small-scale wastewater treatment systems typically in regional and rural areas with less sophisticated treatment processes and often managed by local governments or communities. Research and industrial applications have demonstrated that online UV-Vis sensors have great potential for improving wastewater monitoring and treatment processes. Existing studies on the development of surrogate parameters with models from spectral data for wastewater were largely limited to lab-based. In contrast, industrial applications of these sensors have primarily targeted large wastewater treatment plants (WWTPs), leaving a gap in research for small-scale WWTPs. This paper demonstrates the suitability of using a field-based online UV-Vis sensor combined with advanced data analytics for CWMSs as an early warning for process upset to support sustainable operations. An industry case study is provided to demonstrate the development of surrogate monitoring parameters for total suspended solids (TSSs) and chemical oxygen demand (COD) using the UV-Vis spectral data from an online UV-Vis sensor. Absorbances at a wavelength of 625 nm (UV625) and absorbances at a wavelength of 265 nm (UV265) were identified as surrogate parameters to measure TSSs and COD, respectively. This study contributes to the improvement of WWTP performance with a continuous monitoring system by developing a process monitoring framework and optimization strategy.

Change characteristics, bacteria host, and spread risks of bioaerosol ARGs/MGEs from different stages in sewage and sludge treatment process

The spread of antibiotic resistance genes (ARGs) in the atmospheric environment has seriously threatened human health. Wastewater treatment plants (WWTPs) are an important source of aerosol ARGs. A large WWTP, including sewage treatment process (SWP) and sludge treatment process (SDP), was selected in North China for sampling in this study. The content of ARGs, mobile genetic elements (MGEs), and bacterial genera in sewage/sludge and aerosols from different process stages was detected. The possible correlation between ARGs/ MGEs and bacteria was analyzed. The risk of antibiotic-resistant bacteria was evaluated and the diffusion of ARGs/MGEs was simulated. The results showed that the concentration of ARGs/MGEs varied as the process progressed, and which in the aeration tank was relatively high. The ARGs/MGEs content in SWP aerosol (8.35–163.27 copies/m3) was higher than that in SDP (5.52–16.36 copies/m3). The main ARGs/MGEs detected in SWP aerosol were tnpA-05, tnpA-04, and ermF, while the main ARGs/MGEs detected in SDP aerosol were sul1, ermF, and blaPAO. ARGs were positively correlated with most bacteria and Escherichia coli with ARGs carries higher cytotoxicity. ARGs/MGEs mainly diffused towards the southeast, which may cause harm to urban residents with the diffusion of aerosols. This study provides clues and theoretical basis for preventing the hazards of ARGs from WWTP sources.

Microparticles in Wild and Caged Biota, Sediments, and Water Relative to Large Municipal Wastewater Treatment Plant Discharges.

Anthropogenically modified microparticles including microplastics are present in municipal wastewater treatment plant (WWTP) effluents; however, it is unclear whether biotic exposures are elevated downstream of these outfalls. In the fall of 2019, the present study examined whether microparticle levels in resident fish, environmental samples, and caged organisms were elevated near the Waterloo and Kitchener WWTP outfalls along the Grand River, Ontario, Canada. Wild rainbow darters (Etheostoma caeruleum) were collected from a total of 10 sites upstream and downstream of both WWTPs, along with surface water and sediment samples to assess spatial patterns over an approximately 70-km river stretch. Amphipods (Hyalella azteca), fluted-shell mussels (Lasmigona costata), and rainbow trout (Oncorhynchus mykiss) were also caged upstream and downstream of one WWTP for 14 or 28 days. Whole amphipods, fish digestive tracts, and mussel tissues (hemolymph, digestive glands, gills) were digested with potassium hydroxide, whereas environmental samples were processed using filtration and density separation. Visual identification, measurement, and chemical confirmation (subset only) of microparticles were completed. Elevated abiotic microparticles were found at several upstream reference sites as well as at one or both wastewater-impacted sites. Microparticles in amphipods, all mussel tissues, and wild fish did not show patterns indicative of increased exposures downstream of effluent discharges. In contrast, elevated microparticle counts were found in trout caged directly downstream of the outfall. Across all samples, cellulose fibers (mainly blue and clear colors) were the most common. Overall, results suggest little influence of WWTP effluents on microparticles in biota but rather a ubiquitous presence across most sites that indicates the importance of other point and nonpoint sources to this system. Environ Toxicol Chem 2024;43:1047-1061. © 2024 His Majesty the King in Right of Canada and The Authors. Environmental Toxicology and Chemistry published by Wiley Periodicals LLC on behalf of SETAC. Reproduced with the permission of the Minister of Environment and Climate Change Canada.

Direct application of chemically enhanced primary treatment in a municipal wastewater treatment plant: A case study

A feasible and efficient implementation of an Fe-based chemically enhanced primary treatment (CEPT) in a large conventional wastewater treatment plant (WWTP) was thoroughly evaluated. The influence of the velocity gradient and hydraulic retention time in the coagulation and flocculation stages, as well as the coagulant (FeCl3) dosage, were evaluated at lab-scale. Standard Jar Tests were performed to simulate CEPT, and the results were compared with those obtained by primary settling without coagulant. The increase in FeCl3 dosage and flocculation hydraulic retention time (HRTF) increased the primary settling COD removal capacity between 6.6% and 18.1%, highlighting its effect on the easily biodegradable COD fraction. The COD removal capacity increased up to 16.8% when working with an HRTF of less than 4 min, facilitating CEPT direct application in conventional WWTPs, avoiding the need to incorporate flocculation chamber, with a corresponding decrease in the associated implementation cost. The presence of residual Fe in the primary settling effluent and an increase in the primary sludge volume were the main drawbacks of the process. The coagulation and flocculation velocity gradients or the coagulation hydraulic retention time did not significantly influence the process.

One-Year Investigation of Hepatitis A Virus and Rotavirus in Two Waste Water Treatment Plants in Egypt

Background: Waterborne enteric viruses are evolving source of disease outbreaks and represent a major threat to global public health. The repetitive assessment of water environments is necessary to manage enteric virus-mediated fecal infection and the probable emergence of different variants. Methods: Here, we detected human rotavirus and hepatitis A virus circulating in two wastewater treatment plants, for one year in sewage and sludge samples from two largest wastewater treatment plant (El-Gabal El-Asfar and Zenin) located in Egypt. For this purpose, we examine predefined viruses' prevalence in 72 samples (24 raw sewage samples, 24 treated effluent samples, and 24 sludge) collected from August 2022 to July 2023. Viral RNA was extracted and detected by nested Reverse Transcriptase-Polymerase Chain Reaction (RT-PCR) in case of HAV and by multiplex semi nested RT-PCR In case of rotavirus with the Results: Percentage of detection rate 58.3%, 25% 41.6%, 50%, 16.6%58.6%, 41.6%, 8.3%, 41.6%41.6%, 8.3% and 41.6% for inlet, outlet, sludge in WWTP zenin and WWTP El-Gabal El-Asfar for HAV, RV respectively. Using generic primer result indicated G1P8 was the most common although G2P [4], G1, G2, G3P? G9P [8], G9P [11], G1 P [4] were detected with different percentage. Conclusion: These results demonstrated that HAV and RV still remains in the environment after sewage treatment and could play an important role in maintaining the endemicity of HAV and RV infection. Routine and continuous monitoring of waterborne viruses are most useful approach to understand disease occurrence in communities.

Wastewater-based epidemiology applied at the building-level reveals distinct virome profiles based on the age of the contributing individuals

BackgroundHuman viruses released into the environment can be detected and characterized in wastewater. The study of wastewater virome offers a consolidated perspective on the circulation of viruses within a population. Because the occurrence and severity of viral infections can vary across a person’s lifetime, studying the virome in wastewater samples contributed by various demographic segments can provide valuable insights into the prevalence of viral infections within these segments. In our study, targeted enrichment sequencing was employed to characterize the human virome in wastewater at a building-level scale. This was accomplished through passive sampling of wastewater in schools, university settings, and nursing homes in two cities in Catalonia. Additionally, sewage from a large urban wastewater treatment plant was analysed to serve as a reference for examining the collective excreted human virome.ResultsThe virome obtained from influent wastewater treatment plant samples showcased the combined viral presence from individuals of varying ages, with astroviruses and human bocaviruses being the most prevalent, followed by human adenoviruses, polyomaviruses, and papillomaviruses. Significant variations in the viral profiles were observed among the different types of buildings studied. Mamastrovirus 1 was predominant in school samples, salivirus and human polyomaviruses JC and BK in the university settings while nursing homes showed a more balanced distribution of viral families presenting papillomavirus and picornaviruses and, interestingly, some viruses linked to immunosuppression.ConclusionsThis study shows the utility of building-level wastewater-based epidemiology as an effective tool for monitoring the presence of viruses circulating within specific age groups. It provides valuable insights for public health monitoring and epidemiological studies.