Sensitivity of wastewater-based epidemiology for detection of SARS-CoV-2 RNA in a low prevalence setting

To assist public health responses to COVID-19, wastewater-based epidemiology (WBE) is being utilised internationally to monitor SARS-CoV-2 infections at the community level. However, questions remain regarding the sensitivity of WBE and its use in low prevalence settings. In this study, we estimated the total number of COVID-19 cases required for detection of SARS-CoV-2 RNA in wastewater. To do this, we leveraged a unique situation where, over a 4-month period, all symptomatic and asymptomatic cases, in a population of approximately 120,000, were precisely known and mainly located in a single managed isolation and quarantine facility (MIQF) building. From 9 July to 6 November 2020, 24-hr composite wastewater samples (n = 113) were collected daily from the sewer outside the MIQF, and from the municipal wastewater treatment plant (WWTP) located 5 km downstream. New daily COVID-19 cases at the MIQF ranged from 0 to 17, and for most of the study period there were no cases outside the MIQF identified. SARS-CoV-2 RNA was detected in 54.0% (61/113) at the WWTP, compared to 95.6% (108/113) at the MIQF. We used logistic regression to estimate the shedding of SARS-CoV-2 RNA into wastewater based on four infectious shedding models. With a total of 5 and 10 COVID-19 infectious cases per 100,000 population (0.005 % and 0.01% prevalence) the predicated probability of SARS-CoV-2 RNA detection at the WWTP was estimated to be 28 and 41%, respectively. When a more realistic proportional shedding model was used, this increased to 58% and 87% for 5 and 10 cases, respectively. In other words, when 10 individuals were actively shedding SARS-CoV-2 RNA in a catchment of 100,000 individuals, there was a high likelihood of detecting viral RNA in wastewater. SARS-CoV-2 RNA detections at the WWTP were associated with increasing COVID-19 cases. Our results show that WBE provides a reliable and sensitive platform for detecting infections at the community scale, even when case prevalence is low, and can be of use as an early warning system for community outbreaks.

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Assessment of Microplastics in a Municipal Wastewater Treatment Plant with Tertiary Treatment: Removal Efficiencies and Loading per Day into the Environment

Water ◽

10.3390/w13101339 ◽

2021 ◽

Vol 13 (10) ◽

pp. 1339

Author(s):

Javier Bayo ◽

Sonia Olmos ◽

Joaquín López-Castellanos

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Municipal Wastewater ◽

Removal Rate ◽

Treatment Plant ◽

Source Control ◽

Municipal Wastewater Treatment ◽

Tertiary Treatment ◽

Stable Performance ◽

Wastewater Samples

This study investigates the removal of microplastics from wastewater in an urban wastewater treatment plant located in Southeast Spain, including an oxidation ditch, rapid sand filtration, and ultraviolet disinfection. A total of 146.73 L of wastewater samples from influent and effluent were processed, following a density separation methodology, visual classification under a stereomicroscope, and FTIR analysis for polymer identification. Microplastics proved to be 72.41% of total microparticles collected, with a global removal rate of 64.26% after the tertiary treatment and within the average retention for European WWTPs. Three different shapes were identified: i.e., microfiber (79.65%), film (11.26%), and fragment (9.09%), without the identification of microbeads despite the proximity to a plastic compounding factory. Fibers were less efficiently removed (56.16%) than particulate microplastics (90.03%), suggesting that tertiary treatments clearly discriminate between forms, and reporting a daily emission of 1.6 × 107 microplastics to the environment. Year variability in microplastic burden was cushioned at the effluent, reporting a stable performance of the sewage plant. Eight different polymer families were identified, LDPE film being the most abundant form, with 10 different colors and sizes mainly between 1–2 mm. Future efforts should be dedicated to source control, plastic waste management, improvement of legislation, and specific microplastic-targeted treatment units, especially for microfiber removal.

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Prevalence of Antibiotic-Resistant Bacteria ESKAPE among Healthy People Estimated by Monitoring of Municipal Wastewater

Antibiotics ◽

10.3390/antibiotics10050495 ◽

2021 ◽

Vol 10 (5) ◽

pp. 495

Author(s):

Masateru Nishiyama ◽

Susan Praise ◽

Keiichi Tsurumaki ◽

Hiroaki Baba ◽

Hajime Kanamori ◽

...

Keyword(s):

Antibiotic Resistance ◽

General Population ◽

Municipal Wastewater ◽

Treatment Plant ◽

Multidrug Resistant ◽

Resistant Bacteria ◽

Municipal Wastewater Treatment ◽

Antibiotic Resistant ◽

Carbapenem Resistant ◽

Wastewater Samples

There is increasing attention toward factors that potentially contribute to antibiotic resistance (AR), as well as an interest in exploring the emergence and occurrence of antibiotic resistance bacteria (ARB). We monitored six ARBs that cause hospital outbreaks in wastewater influent to highlight the presence of these ARBs in the general population. We analyzed wastewater samples from a municipal wastewater treatment plant (MWWTP) and hospital wastewater (HW) for six species of ARB: Carbapenem-resistant Enterobacteria (CARBA), extended-spectrum β-lactamase producing Enterobacteria (ESBL), multidrug-resistant Acinetobacter (MDRA), multidrug-resistant Pseudomonas aeruginosa (MDRP), methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant Enterococci (VRE). We registered a high percentage of ARBs in MWWTP samples (>66%) for all ARBs except for MDRP, indicating a high prevalence in the population. Percentages in HW samples were low (<78%), and no VRE was detected throughout the study. CARBA and ESBL were detected in all wastewater samples, whereas MDRA and MRSA had a high abundance. This result demonstrated the functionality of using raw wastewater at MWWTP to monitor the presence and extent of ARB in healthy populations. This kind of surveillance will contribute to strengthening the efforts toward reducing ARBs through the detection of ARBs to which the general population is exposed.

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Development of wastewater pooled surveillance of SARS-CoV-2 from congregate living settings

Applied and Environmental Microbiology ◽

10.1128/aem.00433-21 ◽

2021 ◽

Author(s):

Lisa M. Colosi ◽

Katie E. Barry ◽

Shireen M. Kotay ◽

Michael D. Porter ◽

Melinda D. Poulter ◽

...

Keyword(s):

Municipal Wastewater ◽

Treatment Plant ◽

Warning System ◽

Practical Method ◽

Diagnostic Methods ◽

Molecular Diagnostic ◽

Clinical Testing ◽

Municipal Wastewater Treatment ◽

Sample Collection ◽

Future Work

Wastewater-based monitoring for SARS-CoV-2 at individual building-level could be an efficient, passive means of early detection of new cases in congregate living settings, but this approach has not been validated. Preliminary samples were collected from a hospital and a local municipal wastewater treatment plant. Molecular diagnostic methods were compared side-by-side to assess feasibility, performance and sensitivity. Refined sample collection and processing protocols were then used to monitor two occupied dormitory complexes (n = 105 and 66) over eight weeks. Wastewater results were validated using known case counts from external clinical testing of building occupants. Results confirm that ultracentrifugation from a 24 hour composite collection had a sensitivity of 96.2% and a specificity of 100%. However, the method could not distinguish new infectious cases from persistent convalescent shedding of SARS-CoV-2 RNA. If the detection of convalescent shedding is considered a false positive, then the sensitivity is 100% and specificity drops to 45%. It was determined that the proposed approach constitutes a highly sensitive wastewater surveillance method for detecting SARS-CoV-2, but it could not distinguish new infectious cases from persistent convalescent shedding. Future work must focus on approaches to distinguish new infections from convalescent shedding to fully realize the potential of building wastewater as a surveillance tool for congregate living. Importance Some of the most severe outbreaks of COVID-19 have taken place in places where persons live together, such as a nursing homes. Wastewater testing from individual buildings could be used for frequent pooled surveillance of virus from all occupants, including those who are contagious with or without symptoms. This work provides a sensitive practical method for detecting infected individuals, as validated in two building complexes housing occupants who underwent frequent clinical testing performed by external entities. Although this sensitive method could be deployed now for pooled surveillance as an early warning system to limit outbreaks, the study shows that the approach will require further refinement to differentiate between contagious newly infected individuals from persons who have persistent viral fragments shedding in their stool outside the contagious period.

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Assessment of Microplastics in a Municipal Wastewater Treatment Plant With Tertiary Treatment: Removal Efficiencies and Loading Per Day Into the Environment

10.21203/rs.3.rs-258840/v1 ◽

2021 ◽

Author(s):

Javier Bayo ◽

Sonia Olmos ◽

Joaquín López-Castellanos

Keyword(s):

Wastewater Treatment ◽

Wastewater Treatment Plant ◽

Municipal Wastewater ◽

Removal Rate ◽

Treatment Plant ◽

Source Control ◽

Municipal Wastewater Treatment ◽

Tertiary Treatment ◽

Stable Performance ◽

Wastewater Samples

Abstract This study investigates the removal of microplastics from wastewater in an urban wastewater treatment plant located in Southeast Spain, including an oxidation ditch, rapid sand filtration, and ultraviolet disinfection. A total of 146.73 L of wastewater samples from influent and effluent were processed, following a density separation methodology, visual classification under a stereomicroscope, and FTIR analysis for polymer identification. Microplastics proved to be 72.41% of total microparticles collected, with a global removal rate of 64.26% after the tertiary treatment and within the average retention for European WWTPs. Three different shapes were identified: i.e., microfiber (79.65%), film (11.26%), and fragment (9.09%), without the identification of microbeads despite the proximity to a plastic compounding factory. Fibers were less efficiently removed (56.16%) than particulate microplastics (90.03%), suggesting that tertiary treatments clearly discriminate among forms, and reporting a daily emission of 1.6 x 107 microplastics to the environment. Year variability in microplastic burden was cushioned at the effluent, reporting a stable performance of the sewage plant. Eight different polymer families were identified, LDPE film being the most abundant form. Future efforts should be carried on source control, plastic waste management, improvement of legislation, and specific microplastic-targeted treatment units, especially for microfiber removal.

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Fate of triclosan in tertiary wastewater treatment: chlorination

Water Quality Research Journal ◽

10.2166/wqrjc.2013.108 ◽

2013 ◽

Vol 48 (4) ◽

pp. 333-343 ◽

Cited By ~ 1

Author(s):

Jennifer Pape ◽

Million B. Woudneh ◽

Richard Grace ◽

A. Ronald MacGillivray ◽

Thomas Fikslin ◽

...

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Wastewater Treatment Plants ◽

Treatment Plant ◽

Transformation Products ◽

Residual Chlorine ◽

Municipal Wastewater Treatment ◽

Delaware River ◽

Before And After ◽

Wastewater Samples

Behavior of the antimicrobial triclosan (5-chloro-2-(2,4-dichlorophenoxy)phenol) was investigated under laboratory chlorination conditions and in a wastewater treatment plant discharging 380 million liters daily to the Delaware River, USA. Reactions of triclosan with chlorine were investigated using concentrations and exposure time typical of municipal wastewater treatment plants, i.e., 1 h contact time and average 1–2 mg/L residual chlorine. In reagent water, triclosan reacted quickly, transforming into mono- and dichlorinated species and further into dichlorophenol and trichlorophenol. However, triclosan remained stable for up to 2 h in wastewater samples chlorinated under these conditions. To confirm observed behavior under field conditions, a liquid chromatography tandem mass spectrometry-based analytical method capable of monitoring triclosan and its transformation products in wastewater was developed. Qualitative and quantitative wastewater characterization before and after chlorination are presented. Triclosan was present at the same concentration (P > 0.05) in pre-chlorination and post-chlorination aqueous wastewater samples (mean 368 ng/L). This finding is consistent with the non-detection of specific triclosan transformation products above sample reporting limits (30.0–100 ng/L), but contrasts markedly with detection of chlorination transformation products reported in reagent water. These data suggest the importance of influent matrix components in chlorination reactions of triclosan in contaminated wastewater under treatment plant conditions.

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WASTEWATER DISINFECTION BY UV AT TRANI MUNICIPAL PLANT

Water Science & Technology ◽

10.2166/wst.1994.0173 ◽

1994 ◽

Vol 30 (4) ◽

pp. 125-132 ◽

Cited By ~ 2

Author(s):

D. Carnimeo ◽

E. Contini ◽

R. Di Marino ◽

F. Donadio ◽

L. Liberti ◽

...

Keyword(s):

Wastewater Treatment ◽

Municipal Wastewater ◽

Treatment Plant ◽

Continuous Operation ◽

Secondary Effluent ◽

Municipal Wastewater Treatment ◽

South Italy ◽

Wastewater Disinfection ◽

Pilot Investigation ◽

Effluent Characteristics

The pilot investigation on the use of UV as an alternative disinfectant to NaOCI was started in 1992 at Trani (South Italy) municipal wastewater treatment plant (335 m3/h). The results collected after six months continuous operation enabled us to compare UV and NaOCl disinfection effectiveness on the basis of secondary effluent characteristics, quantify photoreactivation effects, evidence possible DBP formation and assess costs.

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Performance of hybrid small wastewater treatment system consisting of jet mixed separator and rotating biological contactor

Water Science & Technology ◽

10.2166/wst.1997.0244 ◽

1997 ◽

Vol 35 (6) ◽

pp. 63-70 ◽

Cited By ~ 3

Author(s):

Yoshimasa Watanabe ◽

Yoshihiko Iwasaki

Keyword(s):

Wastewater Treatment ◽

Electric Power ◽

Hybrid System ◽

Municipal Wastewater ◽

Treatment Plant ◽

Treatment System ◽

Municipal Wastewater Treatment ◽

Wastewater Treatment System ◽

Pre Treatment ◽

Organic Particles

This paper describes a pilot plant study on the performance of a hybrid small municipal wastewater treatment system consisting of a jet mixed separator(JMS) and upgraded RBC. The JMS was used as a pre-treatment of the RBC instead of the primary clarifier. The treatment capacity of the system was fixed at 100 m3/d, corresponding to the hydraulic loading to the RBC of 117 L/m2/d. The effluent from the grid chamber at a municipal wastewater treatment plant was fed into the hybrid system. The RBC was operated using the electric power produced by a solar electric generation panel with a surface area of 8 m2 under enough sunlight. In order to reduce the organic loading to the RBC, polyaluminium chloride(PAC) was added to the JMS influent to remove the colloidal and suspended organic particles. At the operational condition where the A1 dosage and hydraulic retention time of the JMS were fixed at 5 g/m3 and 45 min., respectively, the average effluent water quality of hybrid system was as follows: TOC=8 g/m3, Total BOD=8 g/m3, SS=8 g/m3, Turbidity=6 TU, NH4-N=7 g/m3, T-P=0.5 g/m3. In this operating condition, electric power consumption of the RBC for treating unit volume of wastewater is only 0.07 KWH/m3.

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Treatment of Rural Domestic Sewage by Solar Ozonic Ecological Sewage Treatment Plant

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.955-959.3393 ◽

2014 ◽

Vol 955-959 ◽

pp. 3393-3399 ◽

Cited By ~ 1

Author(s):

Wei Zheng ◽

Yan Ming Yang ◽

Yun Long Li ◽

Jian Qiu Zheng

Keyword(s):

Municipal Wastewater ◽

Operating Cost ◽

Sewage Treatment ◽

Sewage Treatment Plant ◽

Treatment Plant ◽

Domestic Sewage ◽

Design Parameters ◽

Small Scale ◽

Municipal Wastewater Treatment ◽

Average Percentage

The process technique and design parameters of project of Solar Ozonic Ecological Sewage Treatment Plant (short for SOESTP) which consists of anaerobic reactor, horizontal subsurface flow (HSSF) constructed wetlands(CWs) and the combination of solar power and ozone disinfection are described, the paper further examines the removal efficiency for treating rural domestic sewage, running expense and recycling ability of product water. The results show that the average percentage removal values of CODcr，BOD5，SS，TN，NH3-N，TP range from 95.6% to 98.0%, 96.0% to 98.7%, 93.1% to 96.1%, 97.0% to 98.9%, 96.9% to 99.5%, 98.2% to 99.6%, respectively, the reduction of fecal coliform (FC) reaches 99.9%, the effluent quality meets the first level A criteria specified in Discharge Standard of Pollutants for Municipal Wastewater Treatment Plant（GB18918-2002）. The running cost of SOESTP is 0.063yuan/ m3, saves much more than traditional sewage treatment, and the ozone water obtained from the reservoir will be an ideal choice for disinfection .The system has characteristics of easy manipulation, low operating cost, achieving advanced water, energy conservation and environment protection, is thought to be very suitable for use as the promotion of rural small - scale sewage treatment.

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