COVID-19 trends at the University of Tennessee: predictive insights from raw sewage SARS-CoV-2 detection and evaluation and PMMoV as an indicator for human waste.

Wastewater-based epidemiology (WBE) has become a valuable tool for monitoring the prevalence of SARS-CoV-2 on university campuses. However, concerns about effectiveness of raw sewage as a COVID-19 early warning system still exist, and it's not clear how useful normalization by simultaneous comparison of Pepper Mild Mottle Virus (PMMoV) is in addressing variations resulting from fecal discharge dilution. This study aims to contribute insights into these aspects by conducting an academic-year field trial at the student residences on the University of Tennessee, Knoxville campus, raw sewage. This was done to investigate the correlations between SARS-CoV-2 RNA load, both with and without PMMoV normalization, and various parameters, including active COVID-19 cases, self-isolations, and their combination among all student residents. Significant positive correlations between SARS-CoV-2 RNA load a week prior, during the monitoring week, and the subsequent week with active cases. Despite these correlations, normalization by PMMoV does not enhance these associations. These findings suggest the potential utility of SARS-CoV-2 RNA load as an early warning indicator and provide valuable insights into the application and limitations of WBE for COVID-19 surveillance specifically within the context of raw sewage on university campuses.

A snapshot of SARS-CoV-2 viral RNA throughout wastewater treatment plants in Arkansas.

The severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) can spread the viral RNA in wastewater by the feces of those experience COVID-19 symptoms. While wastewater monitoring of SARS-CoV-2 in the raw sewage has been confirmed as an effective tool to predict COVID-19 infection, the goal of this study is to assess the presence of SARS-CoV-2 viral RNA throughout various wastewater treatment processes. Wastewater samples were collected from wastewater treatment plants (WWTPs) in the state of Arkansas from August 2020 to June 2021 and measured for the relative concentration of SARS-CoV-2 viral RNA using RT-qPCR. The gene concentrations in the raw wastewater measured in this study were similar to other published studies, targeting the N1 and N2 genes of the virus. The viral RNA concentration was measured after each wastewater treatment step within WWTPs, including primary sedimentation, activated sludge, filtration and disinfection. Results show the most viral RNA removal occurred in the secondary treatment (activated sludge). The viral RNA was only occasionally detected after disinfection (chlorination or UV disinfection). Overall, WWTPs can remove the SARS-CoV-2 viral RNA at an average of 98.7%, while complete removal was achieved on 82% of the sampling days. Further investigation is required to ensure complete viral RNA removal from wastewater such as improving existing treatment process or supplementing with additional treatment steps. PRACTITIONER POINTS: The viral RNA of SARS-CoV-2 was detected in Arkansas wastewater treatment plants. SARS-CoV-2 was rarely detected in treated effluent from wastewater treatment plants. Activated sludge was effective removing SARS-CoV-2 viral RNA from wastewater. This study was limited by the direct RNA extraction from wastewater, which lowered the sensitivity of detection.

Soil fertility and agro-physiological responses of maize (Zea mays) irrigated by treated domestic wastewater by hybrid multi-soil-layering technology.

The depletion of water resources has gained global attention, particularly in arid climates, where there is growing interest in reusing treated wastewater for irrigation. This study focuses on the impact of irrigating treated wastewater using a hybrid multi-soil-layering (MSL) technology on soil physicochemical properties and the agro-physiological characteristics of maize (Zea mays) cultivated in Morocco, a region characterized by arid conditions. To achieve this research goals, three plots were cultivated with Zea mays and subjected to irrigation with water of varying qualities: raw wastewater (RWW), treated wastewater (TWW), and well water (WW). This experiment ran for five months, covering one crop season. The physicochemical and microbiological parameters in the soil and water were investigated, and the agro-physiological characteristics of the maize crops were assessed. The findings revealed significant differences in physicochemical and microbial parameters within both water and soil, as well as in the physiological responses of the maize crop, among the three water treatments. TWW's quality met the permissible limits for direct wastewater discharge, as prescribed by Moroccan norms, making it suitable for potential irrigation reuse. Moreover, the higher content of key elements (Na, K, Ca, and Mg) in WW indicated that TWW was more suitable for irrigation. Zea mays irrigated with RWW and TWW exhibited a higher accumulation of protein and sugar content compared to WW irrigation. Furthermore, the biomass parameters, including root, aerial, and grain dry weight, showed a positive effect on Zea mays irrigated with RWW and TWW compared to WW. Total chlorophyll content, on the other hand, was highest in plants irrigated with WW, followed by TWW. Plants irrigated with RWW produced the highest amounts of nitrogen, phosphorus, and potassium. Conversely, plants irrigated with WW had a higher content of Ca, Na, and Mg. TWW yielded medium concentrations of N, P, K, Ca, Mg, and Na compared to RWW and WW, attributed to the nutrients provided by irrigation with TWW using the hybrid MSL technology. In conclusion, aside from their use as irrigation water, treated wastewater emerges as a valuable source of plant nutrients and soil fertilizers. They offer significant nutritive value, enhancing plant growth, reducing the need for additional fertilizer application, lowering mineral fertilization costs, and increasing the productivity of infertile soils. This highlights the potential of treated wastewater to improve agricultural sustainability in arid regions like Morocco.

SARS-CoV-2 raw wastewater surveillance from student residences on an urban university campus.

The COVID-19 pandemic brought about an urgent need to monitor the community prevalence of infection and detect the presence of SARS-CoV-2. Testing individual people is the most reliable method to measure the spread of the virus in any given community, but it is also the most expensive and time-consuming. Wastewater-based epidemiology (WBE) has been used since the 1960s when scientists implemented monitoring to measure the effectiveness of the Polio vaccine. Since then, WBE has been used to monitor populations for various pathogens, drugs, and pollutants. In August 2020, the University of Tennessee-Knoxville implemented a SARS-CoV-2 surveillance program that began with raw wastewater surveillance of the student residence buildings on campus, the results of which were shared with another lab group on campus that oversaw the pooled saliva testing of students. Sample collection began at 8 am, and the final RT-qPCR results were obtained by midnight. The previous day's results were presented to the campus administrators and the Student Health Center at 8 am the following morning. The buildings surveyed included all campus dormitories, fraternities, and sororities, 46 buildings in all representing an on-campus community of over 8,000 students. The WBE surveillance relied upon early morning "grab" samples and 24-h composite sampling. Because we only had three Hach AS950 Portable Peristaltic Sampler units, we reserved 24-h composite sampling for the dormitories with the highest population of students. Samples were pasteurized, and heavy sediment was centrifuged and filtered out, followed by a virus concentration step before RNA extraction. Each sample was tested by RT-qPCR for the presence of SARS-CoV-2, using the CDC primers for N Capsid targets N1 and N3. The subsequent pooled saliva tests from sections of each building allowed lower costs and minimized the total number of individual verification tests that needed to be analyzed by the Student Health Center. Our WBE results matched the trend of the on-campus cases reported by the student health center. The highest concentration of genomic copies detected in one sample was 5.06 × 107 copies/L. Raw wastewater-based epidemiology is an efficient, economical, fast, and non-invasive method to monitor a large community for a single pathogen or multiple pathogen targets.

The Effects of Wastewater Treatment Plant Failure on the Gulf of Gdansk (Southern Baltic Sea).

In August 2019 and during August/September 2020, the main collection system of the Wastewater Treatment Plant (WWTP) in Warsaw, Poland, malfunctioned. During that system failure, over 4.8 million m3 of untreated wastewater was dropped directly into the Vistula River in just a few days. It is currently considered as one of the largest known failures of WWTP worldwide. In order to assess the environmental impact, water samples were collected from 2 spots at the Vistula river estuary (406 and 415 km from the discharge location, respectively), and 4 spots at the Gulf of Gdansk, situated on the southern shore of the Baltic Sea. The sampling was conducted before the wastewater wave reached the Vistula river's mouth, followed by daily sampling during 21 days after the malfunction occurred. The study showed the decline in water quality at the Vistula river estuary and the Baltic shore waters as the wave of wastewater reached those points, despite being situated over 400 km downstream from the place of the accident. Those changes included the reduction in the dissolved oxygen content (by 0.69-fold at its peak), the increase in Total Organic Carbon (TOC) (by 1.28-fold at its peak), nitrate-nitrogen (N-NO3) (by 1.68-fold at its peak), phosphorous (P) (by 2.41-fold at its peak), conductivity (by 16.8-fold at its peak), and Chemical Oxygen Demand (COD) (by 1.84-fold). In the samples from the Vistula river, the decline in water quality was seen as incidental and lasted 2-3 days. Subsequently, the levels of physical and chemical parameters returned to the levels from before the accident. However, the changes in the Gulf of Gdansk lasted significantly longer, especially on the West side of the Vistula river, where, even after 21 days from the initial accident, some parameters remained altered.

Development of green polylactic acid asymmetric ultrafiltration membranes for nutrient removal.

Polylactides are a prominent class of biocompatible and biodegradable polymers that can be used to fabricate membranes for wastewater treatment. Excessive nutrient (phosphorus and nitrogen) concentrations in water bodies are a serious concern that has resulted in widespread health problems and potable water shortages. In this study, ultrafiltration (UF) membranes were prepared from polylactic acid (PLA) using the phase inversion method. Scanning electron microscope (SEM), thermogravimetric analyzer (TGA), and Fourier-transform infrared (FTIR) analysis were used to characterize the membranes. The hydrophilicity of the membrane surface was investigated by analyzing the water contact angle (CA). The results showed that the PLA membranes had a finger-like asymmetric morphology and various dense pore sizes. When the concentration of the PLA polymer increased from 15% to 20%, the removal of ammonium­nitrogen (NH4+-N) increased from 41.9 ± 1.3% to 95.9 ± 3.1% and from 50% to 87% for synthetic and raw wastewater samples, respectively. Up to 52% removal rates of phosphates (PO43--P) were achieved using PLA membranes. This study revealed a great opportunity to develop green, efficient, and sustainable PLA membranes for the treatment of wastewater with high nutrient content.

Novel techniques to determine dilution ratios of raw wastewater and wastewater treatment plant effluent in the 5-day biochemical oxygen demand test.

The current 5-day biochemical oxygen demand (BOD5) test methods lack detailed information on sample dilution, which typically leads to an incorrect dilution ratio of samples and failed BOD5 testing. This study proposed an improved dilution technique that effectively determines the dilution ratios for raw wastewater and wastewater treatment plants (WWTPs) effluent. The numbers of raw wastewater and WWTPs effluent samples used in the BOD5 tests were 201 and 61, respectively. The experimental results demonstrated that both the raw wastewater and WWTPs effluent varied in BOD5 values with the sample dilution ratio, and these changes were more noticeable when the dissolved oxygen consumption ratio (DOCR) was less than 20% or when the dilution ratio was large. Assuming that the BOD5 value over the DOCR range of 40%-70% was true, the optimal DOCR range was 40%-90% for the raw wastewater and 40%-70% and 80%-90% for the WWTPs effluent, where the relative error of BOD5 values in these DOCR ranges was less than 10% depending on the dilution ratio. The correlation between the sample dilution ratio and the BOD5 value over the optimal DOCR range was considerably higher than that over the entire DOCR range. This was combined with the correlation equation between BOD5 and chemical oxygen demand to propose an equation that could determine more accurate sample dilution ratios for raw wastewater and WWTPs effluent compared to the conventional sample dilution methods for the BOD5 test.

A review on occurrence of emerging pollutants in waters of the MENA region.

Little is known about the occurrence of emerging pollutants (EPs) in waters in the Middle East and North Africa (MENA) region despite the extensive use of low-quality water there. Available data dealing with the sources, occurrence and removal of EPs within the MENA region in different categories of water is collected, presented and analyzed in this literature review. According to the collected database, the occurrence and removal efficiency of EPs in the water matrix in the MENA region is available, respectively, for 13 and six countries of the 18 in total; no available data is registered for the rest. Altogether, 290 EPs have been observed in different water matrices across the MENA countries, stemming mainly from industrial effluents, agricultural practices, and discharge or reuse of treated wastewater (TWW). Pharmaceutical compounds figure among the most frequently reported compounds in wastewater, TWW, surface water, and drinking water. Nevertheless, pesticides are the most frequently detected pollutants in groundwater. Worryingly, 57 cases of EPs have been reported in different fresh and drinking waters, exceeding World Health Organization (WHO) and European Commission (EC) thresholds. Overall, pharmaceuticals, organic compounds, and pesticides are the most concerning EP groups. The review revealed the ineffectiveness of treatment processes used in the region to remove EPs. Negative removals of some EPs such as carbamazepine, erythromycin, and sulfamethoxazole were recorded, suggesting their possible accumulation or release during treatment. This underlines the need to set in place and strengthen control measures, treatment procedures, standards, and policies for such pollutants in the region.

Wastewater-based epidemiology to assess human exposure to personal care and household products - A review of biomarkers, analytical methods, and applications.

Humans are nowadays exposed to numerous chemicals in our day-to-day life, including parabens, UV filters, phosphorous flame retardants/plasticizers, bisphenols, phthalates and alternative plasticizers, which can have different adverse effects to human health. Estimating human's exposure to these potentially harmful substances is, therefore, of paramount importance. Human biomonitoring (HBM) is the existing approach to assess exposure to environmental contaminants, which relies on the analysis of specific human biomarkers (parent compounds and/or their metabolic products) in biological matrices from individuals. The main drawback is its implementation, which involves complex cohort studies. A novel approach, wastewater-based epidemiology (WBE), involves estimating exposure from the analysis of biomarkers in sewage (a pooled urine and feces sample of an entire population). One of the key challenges of WBE is the selection of biomarkers which are specific to human metabolism, excreted in sufficient amounts, and stable in sewage. So far, literature data on potential biomarkers for estimating exposure to these chemicals are scattered over numerous pharmacokinetic and HBM studies. Hence, this review provides a list of potential biomarkers of exposure to more than 30 widely used chemicals and report on their urinary excretion rates. Furthermore, the potential and challenges of WBE in this particular field is discussed through the review of pioneer WBE studies, which for the first time explored applicability of this novel approach to assess human exposure to environmental contaminants. In the future, WBE could be potentially applied as an "early warning system", which could promptly identify communities with the highest exposure to environmental contaminants.

Occurrence of coliphage in raw wastewater and in ambient water: A meta-analysis.

Coliphage have been proposed as indicators of fecal contamination in recreational waters because they better reflect the persistence of pathogenic viruses in the environment and through wastewater treatment than traditional fecal indicator bacteria. Herein, we conducted a systematic literature search of peer-reviewed publications to identify coliphage density data (somatic and male-specific, or MSC) in raw wastewater and ambient waters. The literature review inclusion criteria included scope, study quality, and data availability. A non-parametric two-stage bootstrap analysis was used to estimate the coliphage distributions in raw wastewater and account for geographic region and season. Additionally, two statistical methodologies were explored for developing coliphage density distributions in ambient waters, to account for the nondetects in the datasets. In raw wastewater, the analysis resulted in seasonal density distributions of somatic coliphage (SC) (mean 6.5 log10 plaque forming units (PFU)/L; 95% confidence interval (CI): 6.2-6.8) and MSC (mean 5.9 log10 PFU/L; 95% CI: 5.5-6.1). In ambient waters, 49% of MSC samples were nondetects, compared with less than 5% for SC. Overall distributional estimates of ambient densities of coliphage were statistically higher for SC than for MSC (mean 3.4 and 1.0 log10 PFU/L, respectively). Distributions of coliphage in raw wastewater and ambient water will be useful for future microbial risk assessments.

Monitoring population exposure to pesticides based on liquid chromatography-tandem mass spectrometry measurement of their urinary metabolites in urban wastewater: A novel biomonitoring approach.

Biomonitoring studies have documented the high exposure of the population to pesticides which are widely used for crop protection, industrial and household purposes. This is the first study which has measured human urinary metabolites of pesticides in urban wastewater as biomarkers of population exposure. A liquid chromatography-tandem mass spectrometry (LC-MS/MS) method was developed to measure fifteen urinary metabolites selected from the major classes of pesticides. Raw wastewater samples were processed by solid phase extraction (SPE) or direct injection into the LC-MS/MS system. Recoveries ranged from 75 to 115% and the limits of quantification were 1-15ng/L for the SPE method and 40-800ng/L for direct injection. The method was employed for the analysis of 44 composite 24-h wastewater samples collected in seven Italian cities. Most of the target substances were detected at concentrations ranging from 1.1ng/L to 1.6µg/L. The highest concentrations were for some common metabolites of alkyl phosphates and pyrethroids and the specific metabolite of chlorpyrifos and chlorpyrifos-methyl (3,5,6-trichloro-2-pyridinol). The frequency of detection and abundance of most of the measured metabolites were in line with the profiles reported in urine biomonitoring studies. This method is therefore proposed as a novel "biomonitoring approach" for obtaining objective, direct information on the levels of exposure of a specific population to pesticides, and current research is addressed to validate the method identifying the most reliable biomarkers.

Disinfection of raw wastewater and activated sludge effluent using Fenton like reagent.

BACKGROUND AND OBJECTIVES: Water shortage problems have led to find either new water resources or improve wastewater treatment technologies in order to reuse. Due to less performance of previous units in microbial removal, disinfection has become a necessary step in wastewater treatment plants. In the present study performance of hydrogen peroxide (HP) and modified Fenton's reagent (HP + Cu(++)) was considered for the disinfection of raw wastewater (RW) and activated sludge effluent (ASE). MATERIALS AND METHODS: Plastic containers of 10-liter volume each were used for RW and ASE sampling. Microbiological analyses of the RW and ASE were performed in triplicate; before and after the disinfection process. Fecal coliforms were analyzed by the direct (without enrichment) multiple fermentation tube procedure. RESULTS: The results showed that using HP alone did not have any significant disinfection capability. In RW and ASE, the highest dose used in this study could reduce fecal coliforms (FC)s by only 1.54 and 1.16 log-inactivation, respectively. However, Maximum removal efficiency of modified Fenton in RW and ASE was 4.63 and 3.41 log-inactivation, respectively. The results suggested that Cu(++) ions used in combination with H2O2 produced very rigorous synergistic effect, and HP disinfection capacity increased significantly. CONCLUSION: Hydrogen peroxide, when applied alone, was not successful in disinfecting of either RW or ASE, and neither the WHO guideline nor the Iranian standard could be met. However, modified Fenton showed very significant disinfection potential and could reduce FCs under World Health Organization (WHO) guideline and Iranian national standard for agricultural irrigation.