Wastewater-based Epidemiology Studies Research Articles

Viral concentration method biases in the detection of viral profiles in wastewater.

Viral detection methodologies used for wastewater-based epidemiology (WBE) studies have a broad range of efficacies. The complex matrix and low viral particle load in wastewater emphasize the importance of the concentration method. This study focused on comparing three commonly used virus concentration methods: polyethylene glycol precipitation (PEG), immuno-magnetic nanoparticles (IMNP), and electronegative membrane filtration (EMF). Influent and effluent wastewater samples were processed by the methods and analyzed by DNA/RNA quantification and sequencing for the detection of human viruses. SARS-COV-2, Astrovirus, and Hepatitis C virus were detected by all the methods in both sample types. PEG precipitation resulted in the detection of 20 types of viruses in influent and 16 types in effluent samples. The corresponding number of virus types detected was 21 and 11 for IMNP, and 16 and 8 for EMF. Certain viruses were unique to only one concentration method. For example, PEG detected three types of viruses in influent and six types in effluent compared to IMNP, which detected seven types in influent and one type in effluent samples. However, the EMF method appeared to be the least effective, detecting three types in influent and none in effluent samples. Rotavirus was detected in influent sample using IMNP method, whereas EMF and PEG methods failed to yield a similar outcome. Consequently, the potential false negative results pose a risk to the credibility of WBE applications. Therefore, implementation of a proper concentration technique is critical to minimize method biases and ensure accurate viral profiling in WBE studies.IMPORTANCEIn recent years, significant research efforts have been focused on the development of viral detection methodology for wastewater-based epidemiology studies, showing a range of variability in detection efficacies. A proper methodology is essential for an appropriate evaluation of disease prevalence and community health in such studies and necessitates designing a concentration method based on the target pathogenic virus. There remains a need for comparative performance evaluations of methods in the context of detection efficiencies. This study highlights the significant impact of sample matrix, viral structure, and nucleic acid composition on the efficacy of viral concentration methods. Assessing WBE techniques to ensure accurate detection and understanding of viral presence within wastewater samples is critical for revealing viral profiles in municipality wastewater samples.

Multi-biomarker approach for estimating population size in a national-scale wastewater-based epidemiology study

This study identifies biochemical markers (BCIs) that can be used as population markers in wastewater-based epidemiology (WBE) and compares their estimates with other established population size estimation (PE) methods, including census data (PECEN). Several groups of BCIs (64 targets: genetic and chemical markers) were investigated in an intercity study, including 10 cities/towns within England equating to a population of ∼7 million people. Several selection criteria were applied to identify the best BCIs to provide robust estimation of population size at a catchment level: (1) excellent performance with analytical methods; (2) excellent fit of the linear regression model which indicates PE-driven BCI daily loads; (3) low temporal variability in usage; (4) human-linked origin. Only a few tested BCIs showed a strong positive linear correlation between daily BCI loads and PE indicating their low spatiotemporal variability. These are: cimetidine, clarithromycin, metformin, cotinine, bezafibrate, metronidazole and hydroxymetronidazole, diclofenac, and benzophenone 1. However, only high/long term usage pharmaceuticals: cimetidine and metformin as well as cotinine (metabolite of nicotine) performed well when tested in two independent datasets and catchments accounting for both spatial and temporal scales. Strong seasonal usage trends were observed for antihistamines, NSAIDs (anti-inflammatories), antibiotics and UV filters, invalidating them as PE markers. Key conclusions from the study are: (1) Cimetidine is the best performing BCI; (2) Chemical markers outperform genetic markers as PE BCIs; (3) Water utility PE estimates (PEWW) align well with PECEN and PEBCI values; (4) Ammonium/orthophosphate as well as viral PE markers suffer from high temporal variability, hence, they are not recommended as PEBCI markers, and, most importantly, (5) PEBCI calibration/validation at the country/region level is advised in order to establish the best PE markers suited for local/national needs and accounting for site/region specific uncertainties.

Hepatitis A in Latin America: The current scenario.

This review aims to gather and disseminate updated information regarding hepatitis A virus (HAV) in Latin America (LA) in the last 11years, including seroprevalence, post-vaccination studies, virus detection in aqueous matrices and food samples, and outbreak reports. Only 24 seroprevalence studies were published between 2012 and 2023 with 55%-100% reported prevalences of anti-HAV IgG. Among the 25 LA countries, only eight of them have introduced HAV vaccines into their immunisation programs. Outbreaks of hepatitis A occurred between 2017-2019, mainly affecting men who have sex with men in Argentina, Brazil and Chile, probably as a consequence of the abrupt decline of young adults' immunity. This could be due to that young adult have never been infected in childhood (due to socio-health improvements) and are above the cut-off ages to be included when the vaccination programs were introduced. Although scarce, studies focused on environmental and food HAV surveillance have shown viral presence in these samples. Surface waters presented HAV detections between 1.2% and 86.7%, and untreated wastewaters between 2.8% and 70.9%. Genotypes found in all cases were IA and IC. The only wastewater-based epidemiology study showed to be a useful tool as a complement of traditional epidemiological surveillance. Only four LA countries have looked for HAV in food samples, with genome detection rates between 9% and 33%. Latin American HAV circulation scenario is changing. In countries where socioeconomic and sanitary conditions have not improved, the virus persists with high endemicity and the access to the vaccine should be re-evaluated by local governments. In countries where access to clean water, better sanitary conditions and HAV immunisation programs have been implemented, the number of cases among young adults seems to be increasing, alerting health authorities.

Heavy metal contamination in Sungai Petani, Malaysia: a wastewater-based epidemiology study

ABSTRACT The aim of this study was to investigate the use of wastewater-based epidemiology (WBE) to estimate heavy metal exposure in Sungai Petani, Malaysia. Atomic absorption spectroscopy was used to detect copper (Cu), nickel (Ni), zinc (Zn), iron (Fe), and cadmium (Cd) in wastewater from eight sewage treatment facilities in Sungai Petani in January 2022. The heavy metal concentrations were measured in both influent and effluent, and the mean concentrations in the wastewater were found to be in the following order: Fe > Ni > Zn > Cd > Cu, with a 100% detection frequency. The results of WBE estimation showed that Fe, Ni, and Zn had the highest estimated per population exposure levels, while Cd had the lowest. Compared to a similar study conducted in Penang, Malaysia, all metals except Cu were found to have higher concentrations in Sungai Petani, even though it is a non-industrial district. These findings highlight the importance of addressing heavy metal contamination in Sungai Petani and implementing effective risk management and prevention strategies.

A Review of Wastewater-Based Epidemiology Studies for the Assessment of Over-the-Counter Medicines Used as Recreational Drugs: The Example of Dextromethorphan.

The 'recreational use' of selected over-the-counter (OTC) medicines is an unofficial activity. The traditional surveys assessing the use of drugs are affected by the bias of underreporting and are thus unreliable. The development of analytical techniques helps to monitor the substances at trace levels, such as in wastewater, and might be applied to estimate the consumption of an analyte of interest and ensure additional, evidence-based information complementary to population surveys. We reviewed studies focused on evaluating the estimated consumption of drugs as a reliable and unbiased source of evidence-based information (called wastewater-based epidemiology, WBE) to monitor the scale of this phenomenon. We found there is a need to test not only narcotics in the environment but also medicines that may be abused or recreationally used. The reviewed studies show methods that might provide reliable information about consumption of drugs, narcotics, and OTC medications for proposing targeted, preventive actions. Moreover, as all the selected studies were based on mass spectrometry, there is a potential to include the dextromethorphan and/or related compounds as part of the screening for narcotics and OTC drugs that can be socially harmful, overused, or misused. This article reviews the analytical methods for detecting dextromethorphan and/or its transformation products in environmental water samples.

Target and Nontarget Screening to Support Capacity Scaling for Substance Use Assessment through a Statewide Wastewater Surveillance Network in New York.

Wastewater-based epidemiology (WBE) has been widely implemented around the world as a complementary tool to conventional surveillance techniques to inform and improve public health responses. Currently, wastewater surveillance programs in the U.S. are evaluating integrated approaches to address public health challenges across multiple domains, including substance abuse. In this work, we demonstrated the potential of online solid-phase extraction coupled with liquid chromatography-high-resolution mass spectrometry to support targeted quantification and nontargeted analysis of psychoactive and lifestyle substances as a step toward understanding the operational feasibility of a statewide wastewater surveillance program for substance use assessment in New York. Target screening confirmed 39 substances in influent samples collected from 10 wastewater treatment plants with varying sewershed characteristics and is anticipated to meet the throughput demands as the statewide program scales up to full capacity. Nontarget screening prioritized additional compounds for identification at three confidence levels, including psychoactive substances, such as opioid analgesics, phenethylamines, and cathinone derivatives. Consumption rates of 12 target substances detected in over 80% of wastewater samples were similar to those reported by previous U.S.-based WBE studies despite the uncertainty associated with back-calculations. For selected substances, the relative bias in consumption estimates was sensitive to variations in monitoring frequency, and factors beyond human excretion (e.g., as indicated by the parent-to-metabolite ratios) might also contribute to their prevalence at the sewershed scale. Overall, our study marks the initial phase of refining analytical workflows and data interpretation in preparation for the incorporation of substance use assessment into the statewide wastewater surveillance program in New York.

Environmental virology linked to waterborne diseases and foodborne pathogens: Human and animal food viruses

Foodborne illnesses constitute a serious global one health issue. The transmission of foodborne viruses can occur due to inadequate hygiene of food, lack of basic sanitation, poor personal hygiene and consumption of raw or undercooked food. This study aims overview about environmental virology linked to waterborne diseases and foodborne pathogens in human and animal food viruses. Thus, epidemiological studies have proposed some emerging pathogens as possible transmitters of contaminated water ingestion based on biochemical properties and viral structures such as: Picornaviridae (polioviruses, enteroviruses, coxsakiviruses, hepatitis A viruses and echoviruses), Adenoviridae (adenoviruses), Caliciviridae (noroviruses, caliciviruses, astroviruses), and Reoviridae (reoviruses and rotaviruses). These viruses can cause gastrointestinal, liver and central nervous system disorders. In controlling foodborne infections, accurately identifying sources of contamination is a significant challenge, given the complexity of the food production chain. The lack of adequate monitoring and neglect of good health practices contribute to the spread of these infections. Large-scale immunization has contributed to the reduction of enteric outbreaks and eradication of cases in many regions of the world as a prevention of hepatitis A and poliomyelitis. However, challenges such as the lack of effectiveness in inspecting viruses in food increase the risk of outbreaks and epidemics, with emphasis on Noroviruses as the main causes of these infections today. Investment in vaccine research and development has been a fundamental strategy to reduce these statistics, especially in vulnerable groups. Moreover, the implementation molecular-based tools and wastewater-based epidemiology studies to high-throughput for aquatic biomonitoring should be up to date to avoid the risk and impact on public health and aquatic environments. Novel perspectives to control of waterborne viruses has been introduced in continuous surveillance programs for ecosystems monitoring.

Refining the correction factor for a better monitoring of antidepressant use by wastewater-based epidemiology: A case study of amitriptyline

Wastewater-based epidemiology (WBE) is proposed as a cost-effective approach to objectively monitor the antidepressant use but it requires more accurate correction factors (CF) than what had been used in previous studies. Amitriptyline is a popular prescription medicine for treating depression and nerve pain, which could be prone to misuse and need monitoring. The CF of amitriptyline employed in previous WBE studies varied from 10 to 100, leading to substantial disparities between WBE estimates and expected mass of antidepressants in wastewater. Hence, this study aimed to take amitriptyline as a case study and refine the CF by correlating mass loads measured in wastewater from 12.2 million inhabitants collected during the 2016 Census with corresponding annual sales data. The triangulation of WBE data and sales data resulted in a newly-derived CF of 7, which is significantly different from the CF values used in previous studies. The newly derived CF was applied to a secondary, multi-year (2017 to 2020) WBE dataset for validation against sales data in the same period, demonstrating the estimated amitriptyline use (380 ± 320 mg/day/1000 inhabitants) is consistent with sales data (450 ± 190 mg/day/1000 inhabitants). When we applied the new CF to previous studies, the wastewater consumption loads matched better to prescription data than previous WBE estimations. The refined CF of amitriptyline can be used in future WBE studies to improve the accuracy of the consumption estimates.

Exposure to environmental pollutants: A mini-review on the application of wastewater-based epidemiology approach.

Wastewater-based epidemiology (WBE) is considered an innovative and promising tool for estimating community exposure to a wide range of chemical and biological compounds by analyzing wastewater. Despite scholars' interest in WBE studies, there are uncertainties and limitations associated with this approach. This current review focuses on the feasibility of the WBE approach in assessing environmental pollutants, including pesticides, heavy metals, phthalates, bisphenols, and personal care products (PCPs). Limitations and challenges of WBE studies are initially discussed, and then future perspectives, gaps, and recommendations are presented in this review. One of the key limitations of this approach is the selection and identification of appropriate biomarkers in studies. Selecting biomarkers considering the basic requirements of a human exposure biomarker is the most important criterion for validating this new approach. Assessing the stability of biomarkers in wastewater is crucial for reliable comparisons of substance consumption in the population. However, directly analyzing wastewater does not provide a clear picture of biomarker stability. This uncertainty affects the reliability of temporal and spatial comparisons. Various uncertainties also arise from different steps involved in WBE. These uncertainties include sewage sampling, exogenous sources, analytical measurements, back-calculation, and estimation of the population under investigation. Further research is necessary to ensure that measured pollutant levels accurately reflect human excretion. Utilizing data from WBE can support healthcare policy in assessing exposure to environmental pollutants in the general population. Moreover, WBE seems to be a valuable tool for biomarkers that indicate healthy conditions, lifestyle, disease identification, and exposure to pollutants. Although this approach has the potential to serve as a biomonitoring tool in large communities, it is necessary to monitor more metabolites from wastewater to enhance future studies.

A retrospective longitudinal study of adenovirus group F, norovirus GI and GII, rotavirus, and enterovirus nucleic acids in wastewater solids at two wastewater treatment plants: solid-liquid partitioning and relation to clinical testing data.

Enteric infections are important causes of morbidity and mortality, yet clinical surveillance is limited. Wastewater-based epidemiology (WBE) has been used to study community circulation of individual enteric viruses and panels of respiratory diseases, but there is limited work studying the concurrent circulation of a suite of important enteric viruses. A retrospective WBE study was carried out at two wastewater treatment plants located in California, United States. Using digital droplet polymerase chain reaction (PCR), we measured concentrations of human adenovirus group F, enteroviruses, norovirus genogroups I and II, and rotavirus nucleic acids in wastewater solids two times per week for 26 months (n = 459 samples) between February 2021 and mid-April 2023. A novel probe-based PCR assay was developed and validated for adenovirus. We compared viral nucleic acid concentrations to positivity rates for viral infections from clinical specimens submitted to a local clinical laboratory to assess concordance between the data sets. We detected all viral targets in wastewater solids. At both wastewater treatment plants, human adenovirus group F and norovirus GII nucleic acids were detected at the highest concentrations (median concentrations greater than 105 copies/g), while rotavirus RNA was detected at the lowest concentrations (median on the order of 103 copies/g). Rotavirus, adenovirus group F, and norovirus nucleic acid concentrations were positively associated with clinical specimen positivity rates. Concentrations of tested viral nucleic acids exhibited complex associations with SARS-CoV-2 and other respiratory viral nucleic acids in wastewater, suggesting divergent transmission patterns.IMPORTANCEThis study provides evidence for the use of wastewater solids for the sensitive detection of enteric virus targets in wastewater-based epidemiology programs aimed to better understand the spread of enteric disease at a localized, community level without limitations associated with testing many individuals. Wastewater data can inform clinical, public health, and individual decision-making aimed to reduce the transmission of enteric disease.

Wastewater-based Epidemiology to Investigate Spatio-Temporal Trends in Alcohol Consumption in Aotearoa, New Zealand.

Alcohol is an influential drug that has extensive societal impact. In Aotearoa New Zealand, there are a number of worrying trends related to alcohol consumption including rates of alcohol-related harm and violence and heavy episodic drinking. To understand and address these issues, alcohol consumption rates and related trends need to be understood. A wastewater-based epidemiology study was carried out over the course of six months (April-September 2021), sampling one week per month from ten catchment areas covering ~40 % of the national population. The average alcohol consumption was found to be 12.2 mL/person/day. Temporal and geographical trends in alcohol consumption were found; there was higher alcohol consumption on the weekends compared to weekdays, alcohol consumption was inversely related to settlement size, there was increased alcohol consumption due to public holidays and alcohol consumption was not seen to increase during COVID restrictions, however there was a notable change in the weekly trend during lockdowns. This application of alcohol WBE to Aotearoa New Zealand represents a comprehensive national study to understand alcohol consumption and its influences. The knowledge obtained will allow appropriate services and public policies to be reviewed to best serve communities.

Real-Time On-Site Monitoring of Viruses in Wastewater Using Nanotrap® Particles and RICCA Technologies.

Wastewater-based epidemiology (WBE) is an effective and efficient tool for the early detection of infectious disease outbreaks in a community. However, currently available methods are laborious, costly, and time-consuming due to the low concentration of viruses and the presence of matrix chemicals in wastewater that may interfere with molecular analyses. In the present study, we designed a highly sensitive "Quick Poop (wastewater with fecal waste) Sensor" (termed, QPsor) using a joint approach of Nanotrap microbiome particles and RICCA (RNA Isothermal Co-Assisted and Coupled Amplification). Using QPsor, the WBE study showed a strong correlation with standard PEG concentrations and the qPCR technique. Using a closed format for a paper-based lateral flow assay, we were able to demonstrate the potential of our assay as a real-time, point-of-care test by detecting the heat-inactivated SARS-CoV-2 virus in wastewater at concentrations of 100 copies/mL and within one hour. As a proof-of-concept demonstration, we analyzed the presence of viral RNA of the SARS-CoV-2 virus and PMMoV in raw wastewater samples from wastewater treatment plants on-site and within 60 min. The results show that the QPsor method can be an effective tool for disease outbreak detection by combining an AI-enabled case detection model with real-time on-site viral RNA extraction and amplification, especially in the absence of intensive clinical laboratory facilities. The lab-free, lab-quality test capabilities of QPsor for viral prevalence and transmission in the community can contribute to the efficient management of pandemic situations.

Wastewater surveillance for antibiotics and resistance genes in a river catchment: Spatiotemporal variations and the main drivers

Wastewater-based epidemiology (WBE) is used for mining information about public health such as antibiotics resistance. This study investigated the distribution profiles of six types of antibiotic resistance genes (ARGs) in wastewater and rivers in Wuhu City, China. The levels of ARGs found in the Qingyijiang River were significantly higher than other rivers, and were comparable to effluent levels. Among the ARGs, sulfonamides ARGs and intI1 were the predominant in both wastewaters and rivers. Additionally, the concentrations of ARGs were higher on weekends as opposed to weekdays. Their distribution patterns remained consistent inter-week and inter-season using linear regression analysis (p < 0.001). Interestingly, the occurrence levels of ARGs in wastewaters during spring were significantly higher than in autumn, although insignificant in rivers. The apparent removal rate of ARGs in domestic wastewater sources ranged from 61.52–99.29%, except for qepA (-1.91% to 81.09%), whereas the removal rates in mixed domestic and industrial wastewaters showed a marked decrease (-92.94% to 76.67%). A correlation network analysis revealed that azithromycin and erythromycin were key antibiotics, while blaNDM-1, tetM, tetB, and ermB were identified as key ARGs. Sulfonamide and fluoroquinolone antibiotics, and tetracycline and macrolide ARGs were the primary contributors. Linear mixed models demonstrated that socio-economic variables positively impacted the occurrence levels of ARGs, whereas wastewater flow and river runoff were the negative drivers for their concentrations in wastewaters and surface waters, respectively. Overall, this WBE study contributes to the understanding of spatiotemporal profiles and main drivers of the occurrence of ARGs in wastewater and receiving water.

Retrospective spatiotemporal study of antidepressants in Slovenian wastewaters

This study utilizes wastewater-based epidemiology (WBE) to evaluate spatiotemporal changes in the consumption of antidepressants before and during the COVID-19 pandemic in Slovenia. Composite 24-h influent wastewater samples (n = 210) were collected from six wastewater treatment plants between summer 2019 and spring 2021. The samples were extracted using 96-well solid-phase extraction and analysed by liquid chromatography-tandem mass spectrometry. The measured concentrations of target antidepressant biomarkers were then converted to population-normalised mass loads (PNMLs), taking into account flow rate and catchment population. Ten biomarkers, including amitriptyline, bupropion, bupropion-OH, citalopram, norcitalopram, normirtazapine, venlafaxine, O-desmethylvenlafaxine, trazodone, and moclobemide, were above the lower limit of quantification and were included in the spatiotemporal temporal assessment. The highest PNMLs were detected for O-desmethylvenlafaxine (mean ± SD: 82.1 ± 21.2 mg/day/1000 inhabitants) and venlafaxine (38.0 ± 10.6 mg/day/1000 inhabitants), followed by citalopram (27.0 ± 10.7 mg/day/1000 inhabitants). In addition, the mean metabolite/parent compound ratios were comparable with other WBE studies indicating consumption rather than direct disposal. Overall, the results indicated significant spatiotemporal variations depending on the location, and the PNMLs of most biomarkers increased during the first wave of the COVID-19 pandemic (spring of 2020). However, no clear spatial patterns were revealed related to the pandemic.

Designing a Wastewater-Based Epidemiology Study at the U.S. Air Force Academy: Using Severe Acute Respiratory Syndrome Coronavirus 2 to Test a Sentinel System forEarly Disease Outbreak Detection.

The presence of severe acute respiratory syndrome coronavirus 2 (SARS-CoV2) in wastewater has been proposed as a sentinel surveillance epidemiological tool for detection of infectious disease at a community level and as a complementary approach to syndromic surveillance of infectious disease outbreaks. We have designed a study to test the presence and quantity of SARS-CoV2, the virus responsible for COVID19, in the wastewater treatment facility (WWTF) of the U.S. Air Force Academy. Wastewater samples were tested in the laboratory to quantify the amount of SARS-CoV2 RNA using reverse transcription-quantitative polymerase chain reaction. Raw SARS-CoV2 viral titer in wastewater was normalized to the viral titer of a fecal marker, pepper mild mottle virus, to correct for dilutions. Temporal and spatial trends of COVID19 were analyzed. Furthermore, we compared wastewater analysis results against clinical data to assist public health decisions. Preliminary data suggest that wastewater analysis can provide temporal and spatial trends of COVID19. The geographically discrete WWTF at the U.S. Air Force suggests that wastewater testing is a useful approach to developing a comprehensive sentinel surveillance system. Together with ongoing syndromic surveillance data, this proof-of-concept study seeks to determine whether early detection of SARS-CoV2 in a closed system WWTF correlates to changes in community and clinically reported COVID19. The well-documented population served by the geographically discrete WWTF at the U.S. Air Force Academy may serve to better elucidate the adjunctive role of wastewater testing in a comprehensive surveillance system. These results may be of particular interest to the DoD and local commanders given the WWTFs under their immediate control and the information that these studies may provide in support of operational readiness through early detection of disease outbreaks.

Festivals following the easing of COVID-19 restrictions: Prevalence of new psychoactive substances and illicit drugs

The market for illicit drugs and new psychoactive substances (NPS) has grown significantly and people attending festivals have been identified as being at high risk (high extent and frequency of substance use). Traditional public health surveillance data sources have limitations (high costs, long implementation times, and ethical issues) and wastewater-based epidemiology (WBE) can cost-effectively support surveillance efforts. Influent wastewater samples were analyzed for NPS and illicit drug consumption collected during New Year period (from 29-Dec-2021 to 4-Jan-2022) and a summer Festival (from 29-June-2022 to 12-July-2022) in a large city in Spain. Samples were analyzed for phenethylamines, cathinones, opioids, benzodiazepines, plant-based NPS, dissociatives, and the illicit drugs methamphetamine, MDA, MDMA, ketamine, heroin, cocaine, and pseudoephedrine by liquid chromatography mass spectrometry. High consumption rates of specific NPS and established illicit drugs were identified at the peak of each event. Furthermore, a dynamic change in NPS use (presence and absence of substances) was detected over a period of six months. Eleven NPS, including synthetic cathinones, benzodiazepines, plant-based NPS and dissociatives, and seven illicit drugs were found across both the New Year and summer Festival. Statistically significant differences (p < 0.05) were seen for 3-MMC (New Year vs summer Festival), eutylone (New Year vs summer Festival), cocaine (summer Festival vs normal week and summer Festival vs New Year), MDMA (New Year vs normal week and summer Festival vs normal week), heroin (summer Festival vs New Year) and pseudoephedrine (summer Festival vs New Year). This WBE study assessed the prevalence of NPS and illicit drugs at festivals following the reduction of the COVID-19 pandemic restrictions highlighting the high use of specific substances at the peak of each event. This approach identified in a cost-effective and timely manner without any ethical issues the most used drugs and changes in use patterns and, thus, can complement public health information.

Assessing the Presence and Variability of Illicit Drugs and Metabolites in Wastewater Treatment Plants of Southeast Brazil: A Comprehensive Wastewater-Based Epidemiology Study

Assessing the Presence and Variability of Illicit Drugs and Metabolites in Wastewater Treatment Plants of Southeast Brazil: A Comprehensive Wastewater-Based Epidemiology Study

Application of the metal ions as potential population biomarkers for wastewater-based epidemiology: estimating tobacco consumption in Southern China.

Wastewater-based epidemiology (WBE) is an objective approach for the estimation of population-level exposure to a wide range of substances, in which the use of a population biomarker (PB) could significantly reduce back-calculation errors. Although some endogenous or exogenous compounds such as cotinine and other hormones have been developed as PBs, more PBs still need to be identified and evaluated. This study aimed to propose a novel method to estimate population parameters from the mass load of metal ion biomarkers in wastewater, and estimate the consumption of tobacco in 24 cities in Southern China using the developed method. Daily wastewater samples were collected from 234 wastewater treatment plants (WWTPs) in 24 cities in Southern China. Atomic absorption spectroscopy (AAS) was applied to determine the concentrations of common health-related metal ions in wastewater, including sodium (Na), potassium (K), magnesium (Mg), calcium (Ca), iron (Fe), and zinc (Zn), and compared them with the daily mass load of cotinine corresponding to catchment populations. The concentrations of cotinine in wastewater samples were measured using liquid chromatography-tandem mass spectrometry. There were clear and strong correlations between the target metal ion equivalent population and census data. The correlation coefficients (R) were RK = 0.78, RNa = 0.66, RCa = 0.81, RMg = 0.77, and RFe = 0.69, at p < 0.01 and R2 > 0.6. Subsequently, the combination of WBE and metal ion PBs was used to estimate tobacco consumption. Daily consumption of nicotine was estimated to be approximately 1.76 ± 1.19mg/d/capita, equivalent to an average of 13.0 ± 8.75 cigarettes/d being consumed by smokers. The data on tobacco consumption in this study were consistent with those in traditional surveys in Southern China. The metal ion potassium is an appropriate PB for reflecting the real-time population and could be used to evaluate the tobacco consumption in WBE study.

Determination of the pyrethroid inseticide metabolite 3-phenoxybenzoic acid in wastewater using polar organic integrative samplers and LC-MS/MS analysis

Wastewater-based epidemiology (WBE) is a methodological approach that aims to obtain epidemiological information through wastewater analysis, by identifying endogenous metabolism products. Pyrethroid insecticides are commonly used but just a few studies evaluated concentrations of pyrethroid metabolites in wastewater. A cost-effective and efficient sampling strategy for WBE studies is the use of polar organic chemical integrative samplers (POCIS). This study aimed to develop and evaluate a method for estimating the concentration of the pyrethroid insecticide 3-phenoxybenzoic acid (3-PBA) using POCIS sampling and liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis. The sampler sorbent was extracted with methanol, followed by a double solid phase extraction (SPE) clean-up. The extraction procedure had yields in the range of 95.7–100.4 %. There were 27 collection cycles, with POCIS samplers changed every 14 days. The analyte 3-PBA was measured in all collections. The concentration of 3-PBA in the POCIS sorbent was 208.6–2456.9 ng g−1. The sampling rate was 0.096 L/day and the resulting estimated concentration in wastewater was 24.3 to 335.2 ng/L. This is the first study evaluating POCIS sampling to measure a pyrethroid metabolite in water or wastewater samples.

Prediction of COVID-19 positive cases, a nation-wide SARS-CoV-2 wastewater-based epidemiology study

Taking advantage of Estonia's small size and population, we have employed wastewater-based epidemiology approach to monitor the spread of SARS-CoV-2, releasing weekly nation-wide updates. In this study we report results obtained between August 2020 and December 2021. Weekly 24 h composite samples were collected from wastewater treatment plants of larger towns already covered 65% of the total population that was complemented up to 40 additional grab samples from smaller towns/villages and the specific sites of concern.The N3 gene abundance was quantified by RT-qPCR. The N3 gene copy number (concentration) in wastewater fluctuated in accordance with the SARS-CoV-2 spread within the total population, with N3 abundance starting to increase 1.25 weeks (9 days) (95% CI: [1.10, 1.41]) before a rise in COVID-19 positive cases. Statistical model between the load of virus in wastewater and number of infected people validated with the Alpha variant wave (B.1.1.17) could be used to predict the order of magnitude in incidence numbers in Delta wave (B.1.617.2) in fall 2021. Targeted testing of student dormitories, retirement and nursing homes and prisons resulted in successful early discovery of outbreaks. We put forward a SARS-CoV-2 Wastewater Index (SARS2-WI) indicator of normalized virus load as COVID-19 infection metric to complement the other metrics currently used in disease control and prevention: dynamics of effective reproduction number (Re), 7-day mean of new cases, and a sum of new cases within last 14 days. In conclusion, an efficient surveillance system that combines analysis of composite and grab samples was established in Estonia. There is considerable discussion how the viral load in wastewater correlates with the number of infected people. Here we show that this correlation can be found. Moreover, we confirm that an increased signal in wastewater is observed before the increase in the number of infections. The surveillance system helped to inform public health policy and place direct interventions during the COVID-19 pandemic in Estonia via early warning of epidemic spread in various regions of the country.