Testing wastewater to detect illicit drugs: state of the art, potential and research needs

Preparation of amphiphilic poly(divinylbenzene-co-N-vinylpyrrolidone)-functionalized polydopamine magnetic nanoadsorbents for enrichment of synthetic cannabinoids in wastewater

Concerns have been raised about synthetic cannabinoids (SCs), which are among the most often trafficked and used illegal substances. An analytical method that holds promise for determining illicit drug use in the general population is wastewater-based epidemiology (WBE). Unfortunately, the concentration of SCs in wastewater is often extremely low on account of their hydrophobic nature, thus presenting a significant obstacle to the accurate detection and quantification of SCs using WBE. In this study, we present novel magnetic nanomaterials as amphiphilic adsorbents for pretreatment of wastewater using magnetic solid phase extraction (MSPE). Polydopamine-modified Fe3O4 nanoparticles were used as the magnetic core and further functionalized with poly(divinylbenzene-N-vinylpyrrolidone). Coupled with UHPLC-MS/MS analysis, an analytical method to simultaneously detect nine SCs at trace-levels in wastewater was developed and validated, enriching 50 mL wastewater to 100 μL with limits of detection (LOD) being 0.005-0.5 ng L-1, limits of quantification (LOQ) being 0.01-1.0 ng L-1, recoveries ranging from 73.99 to 110.72%, and the intra- and inter-day precision's relative standard deviations less than 15%. In comparison to the time-consuming conventional column-based solid phase extraction, the entire MSPE procedure from sample pre-treatment to data acquisition could be finished in one hour, thus largely facilitating the WBE method for drug surveillance and control.

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.

Campus source to sink wastewater surveillance of severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2)

Wastewater-based surveillance (WBS) offers an aggregate, and cost-effective approach for tracking infectious disease outbreak prevalence within communities, that provides data on community health complementary to individual clinical testing. This study reports on a 16-month WBS initiative on a university campus in England, UK, assessing the presence of SARS-CoV-2 in sewers from large buildings, downstream sewer locations, raw wastewater, partially treated and treated effluents. Key findings include the detection of the Alpha (B.1.1.7) variant in wastewater, with 70 % of confirmed campus cases correlating with positive wastewater samples. Notably, ammonium nitrogen (NH4-N) levels showed a positive correlation (ρ = 0.543, p < 0.01) with virus levels at the large building scale, a relationship not observed at the sewer or wastewater treatment works (WWTW) levels due to dilution. The WWTW was compliant to wastewater standards, but the secondary treatment processes were not efficient for virus removal as SARS-CoV-2 was consistently detected in treated discharges. Tools developed through WBS can also be used to enhance traditional environmental monitoring of aquatic systems. This study provides a detailed source-to-sink evaluation, emphasizing the critical need for the widespread application and improvement of WBS. It showcases WBS utility and reinforces the ongoing challenges posed by viruses to receiving water quality.

Monitoring the use of novel psychoactive substances in Australia by wastewater-based epidemiology

Users of novel psychoactive substances (NPS) are at risk, due to limited information about the toxicity and unpredictable effects of these compounds. Wastewater-based epidemiology (WBE) has been used as a tool to provide insight into NPS use at the population level. To understand the preferences and trends of NPS use in Australia, this study involved liquid chromatography mass spectrometry analysis of wastewater collected from Australian states and territories from February 2022 to February 2023. In total, 59 different NPS were included across two complementary analytical methods and covered up to 57 wastewater catchments over the study. The NPS detected in wastewater were 25-B-NBOMe, buphedrone, 1-benzylpiperazine (BZP), 3-chloromethcathinone, N,N-dimethylpentylone (N,N-DMP), N-ethylheptedrone, N-ethylpentylone, eutylone, 4F-phenibut, 2-fluoro deschloroketamine, hydroxetamine, mephedrone, methoxetamine, methylone, mitragynine, pentylone, phenibut, para-methoxyamphetamine (PMA), alpha-pyrrolidinovalerophenone (α-PVP) and valeryl fentanyl. The detection frequency for these NPS ranged from 3 % to 100 % of the sites analysed. A noticeable decreasing trend in eutylone detection frequency and mass loads was observed whilst simultaneously N,N-DMP and pentylone increased over the study period. The emergence of some NPS in wastewater pre-dates other sources of monitoring and provides further evidence that WBE can be used as an additional early warning system for alerting potential NPS use.

Wastewater sequencing reveals community and variant dynamics of the collective human virome

Wastewater is a discarded human by-product, but its analysis may help us understand the health of populations. Epidemiologists first analyzed wastewater to track outbreaks of poliovirus decades ago, but so-called wastewater-based epidemiology was reinvigorated to monitor SARS-CoV-2 levels while bypassing the difficulties and pit falls of individual testing. Current approaches overlook the activity of most human viruses and preclude a deeper understanding of human virome community dynamics. Here, we conduct a comprehensive sequencing-based analysis of 363 longitudinal wastewater samples from ten distinct sites in two major cities. Critical to detection is the use of a viral probe capture set targeting thousands of viral species or variants. Over 450 distinct pathogenic viruses from 28 viral families are observed, most of which have never been detected in such samples. Sequencing reads of established pathogens and emerging viruses correlate to clinical data sets of SARS-CoV-2, influenza virus, and monkeypox viruses, outlining the public health utility of this approach. Viral communities are tightly organized by space and time. Finally, the most abundant human viruses yield sequence variant information consistent with regional spread and evolution. We reveal the viral landscape of human wastewater and its potential to improve our understanding of outbreaks, transmission, and its effects on overall population health.

Development and validation of a liquid chromatography tandem mass spectrometry method for the analysis of 53 benzodiazepines in illicit drug samples

An LC-MS/MS method for the analysis of 53 benzodiazepines, including various designer benzodiazepines, was developed. The developed method was applied to a total of 79 illicit street drug samples collected in Chicago, IL. Of these samples, 68 (84%) had detectable amounts of at least one benzodiazepine. Further, of the 53 benzodiazepines included in the developed method just 14 were measured in samples. Clonazolam, a potent designer benzodiazepine and derivative of clonazepam, was the most frequently measured benzodiazepine in 63% of samples and was measured in the highest concentrations. Other benzodiazepines measured in more than 10% of samples included clonazepam, alprazolam, flualprazolam, and oxazepam. Mixtures of benzodiazepines were frequently measured in samples, with just 24% of samples containing just one benzodiazepine. To determine the response of benzodiazepines on a rapid, point-of-use drug checking tool, all 53 benzodiazepine standards were screened on a lateral flow immunoassay benzodiazepine test strip. Sixty eight percent of standards gave a positive BTS response at a concentration of 20 μg/mL, demonstrating BTS have response to a wide variety of benzodiazepines, including many designer benzodiazepines. A comparison of this data to previous data reported for the same samples demonstrated all samples containing a benzodiazepine also had an opioid present, with fentanyl being present in 94% of benzodiazepine samples. These results highlight high rates of polysubstance drug presence in Chicago, IL illicit drug samples, posing an increased risk of drug overdoses in people who use drugs.

The role of microorganisms in the biotransformation of psychoactive substances and its forensic relevance: a critical interdisciplinary review

Microorganisms are widespread on the planet being able to adapt, persist, and grow in diverse environments, either rich in nutrient sources or under harsh conditions. The comprehension of the interaction between microorganisms and drugs is relevant for forensic toxicology and forensic chemistry, elucidating potential pathways of microbial metabolism and their implications. Considering the described scenario, this paper aims to provide a comprehensive and critical review of the state of the art of interactions amongst microorganisms and common drugs of abuse. Additionally, other drugs of forensic interest are briefly discussed. This paper outlines the importance of this area of investigation, covering the intersections between forensic microbiology, forensic chemistry, and forensic toxicology applied to drugs of abuse, and it also highlights research potentialities.

Key points

Microorganisms are widespread on the planet and grow in a myriad of environments.Microorganisms can often be found in matrices of forensic interest.Drugs can be metabolized or produced (e.g. ethanol) by microorganisms.

Wastewater-Based Surveillance Does Not Belong in a Regulatory Framework Designed to Protect Waters That Receive Treated Wastewater. Comment on Wright, T.; Adhikari, A. Utilizing a National Wastewater Monitoring Program to Address the U.S. Opioid Epidemic: A Focus on Metro Atlanta, Georgia. Int. J. Environ. Res. Public Health 2023, 20, 5282

We read with great interest the work by Wright and Adhikari on "Utilizing a National Wastewater Monitoring Program to Address the U.S. Opioid Epidemic: A Focus on Metro Atlanta, Georgia" [...].

Normalisation of SARS-CoV-2 concentrations in wastewater: The use of flow, electrical conductivity and crAssphage

Over the course of the Corona Virus Disease-19 (COVID-19) pandemic in 2020-2022, monitoring of the severe acute respiratory syndrome coronavirus 2 ribonucleic acid (SARS-CoV-2 RNA) in wastewater has rapidly evolved into a supplementary surveillance instrument for public health. Short term trends (2 weeks) are used as a basis for policy and decision making on measures for dealing with the pandemic. Normalisation is required to account for the dilution rate of the domestic wastewater that can strongly vary due to time- and location-dependent sewer inflow of runoff, industrial discharges and extraneous waters. The standard approach in sewage surveillance is normalisation using flow measurements, although flow based normalisation is not effective in case the wastewater volume sampled does not match the wastewater volume produced. In this paper, two alternative normalisation methods, using electrical conductivity and crAssphage have been studied and compared with the standard approach using flow measurements. For this, a total of 1116 24-h flow-proportional samples have been collected between September 2020 and August 2021 at nine monitoring locations. In addition, 221 stool samples have been analysed to determine the daily crAssphage load per person. Results show that, although crAssphage shedding rates per person vary greatly, on a population-level crAssphage loads per person per day were constant over time and similar for all catchments. Consequently, crAssphage can be used as a quantitative biomarker for populations above 5595 persons. Electrical conductivity is particularly suitable to determine dilution rates relative to dry weather flow concentrations. The overall conclusion is that flow normalisation is necessary to reliably determine short-term trends in virus circulation, and can be enhanced using crAssphage and/or electrical conductivity measurement as a quality check.

Recent Advances in the Development of Portable Electrochemical Sensors for Controlled Substances

This review article summarizes recent achievements in developing portable electrochemical sensing systems for the detection and/or quantification of controlled substances with potential on-site applications at the crime scene or other venues and in wastewater-based epidemiology. Electrochemical sensors employing carbon screen-printed electrodes (SPEs), including a wearable glove-based one, and aptamer-based devices, including a miniaturized aptamer-based graphene field effect transistor platform, are some exciting examples. Quite straightforward electrochemical sensing systems and methods for controlled substances have been developed using commercially available carbon SPEs and commercially available miniaturized potentiostats. They offer simplicity, ready availability, and affordability. With further development, they might become ready for deployment in forensic field investigation, especially when fast and informed decisions are to be made. Slightly modified carbon SPEs or SPE-like devices might be able to offer higher specificity and sensitivity while they can still be used on commercially available miniaturized potentiostats or lab-fabricated portable or even wearable devices. Affinity-based portable devices employing aptamers, antibodies, and molecularly imprinted polymers have been developed for more specific and sensitive detection and quantification. With further development of both hardware and software, the future of electrochemical sensors for controlled substances is bright.

Model training periods impact estimation of COVID-19 incidence from wastewater viral loads

Wastewater-based epidemiology (WBE) has been deployed broadly as an early warning tool for emerging COVID-19 outbreaks. WBE can inform targeted interventions and identify communities with high transmission, enabling quick and effective responses. As the wastewater (WW) becomes an increasingly important indicator for COVID-19 transmission, more robust methods and metrics are needed to guide public health decision-making. This research aimed to develop and implement a mathematical framework to infer incident cases of COVID-19 from SARS-CoV-2 levels measured in WW. We propose a classification scheme to assess the adequacy of model training periods based on clinical testing rates and assess the sensitivity of model predictions to training periods. A testing period is classified as adequate when the rate of change in testing is greater than the rate of change in cases. We present a Bayesian deconvolution and linear regression model to estimate COVID-19 cases from WW data. The effective reproductive number is estimated from reconstructed cases using WW. The proposed modeling framework was applied to three Northern California communities served by distinct WW treatment plants. The results showed that training periods with adequate testing are essential to provide accurate projections of COVID-19 incidence.

Monitoring Alcohol Consumption in Slovak Cities during the COVID-19 Lockdown by Wastewater-Based Epidemiology

The consumption of alcohol in a population is usually monitored through individual questionnaires, forensics, and toxicological data. However, consumption estimates have some biases, mainly due to the accumulation of alcohol stocks. This study's objective was to assess alcohol consumption in Slovakia during the COVID-19 pandemic-related lockdown using wastewater-based epidemiology (WBE). Samples of municipal wastewater were collected from three Slovak cities during the lockdown and during a successive period with lifted restrictions in 2020. The study included about 14% of the Slovak population. The urinary alcohol biomarker, ethyl sulfate (EtS), was analyzed by liquid chromatography-tandem mass spectrometry (LC-MS/MS). EtS concentrations were used to estimate the per capita alcohol consumption in each city. The average alcohol consumption in the selected cities in 2020 ranged between 2.1 and 327 L/day/1000 inhabitants and increased during days with weaker restrictions. WBE can provide timely information on alcohol consumption at the community level, complementing epidemiology-based monitoring techniques (e.g., population surveys and sales statistics).

Wastewater-based monitoring of illicit drugs in Cyprus by UPLC-MS/MS: The impact of the COVID-19 pandemic

The outbreak and spread of COVID-19 impacted through various ways the lives of millions of humans globally. In this work, wastewater-based epidemiology (WBE) was applied to investigate the effect of the actions taken by the Republic of Cyprus to confine COVID-19 on the use of illicit stimulant drugs. Daily influent samples were collected from the six main wastewater treatment plants (WWTPs) of the country i) before lockdown (3-9 April 2019), ii) during lockdown (21-27 April 2020), iii) during the post-lockdown period (14-20 July 2020), and, iv) during each season of the following year (20-26 April 2021, 19-25 July 2021, 11-17 October 2021, 25 December 2021-2 January 2022), and analyzed for amphetamine, methamphetamine, MDMA and cocaine. In most areas, amphetamine and methamphetamine use was not affected during the confinement period, but as availability of the substances decreased with time, a drop in their use was observed when most restriction measures were eased (up to 9- and 22-fold decrease, respectively). The limitations on social interactions and events during the quarantine period seem to have led to the reduction of MDMA and cocaine and driven a sharp decrease of their use in most areas studied (up to 11 and 6 times lower, respectively). However, the re-opening of activities led to a pronounced consumption increase, reaching maximum daily values of 800 and 2691 mg/1000 inhabitants/day, respectively. In 2021, drug use was re-established to lower levels. The examination of weekly patterns during this year revealed higher weekend use of methamphetamine, MDMA and cocaine. Our results suggest that both the implementation and the easing of COVID-19 related measures affected the availability and the use of drugs. This study also provides the first insight on the consumption of illicit drugs in the Republic of Cyprus during pre-, post- and pandemic times and demonstrates the importance of WBE.

Wastewater research and surveillance: an ethical exploration

The current COVID-19 pandemic has given wastewater research a huge impetus. While wastewater research has some promising applications, there are as yet no well-developed ethical guidelines on how and under what conditions to use wastewater research. The current perspective paper aims to explore the different ethical questions pertaining to wastewater research and surveillance and to provide some tentative guidelines on the desirability of different types of applications. This paper shows that wastewater research offers interesting possibilities, but that legal regulation and ethical guidelines are still lacking, while there are ethical risks involved. The perspective indicates that it is important to look beyond the regulation of data collection and to shift the focus to the question how the analysis and use of wastewater data can be supervised.

Differential biochemical and behavioral responses induced by cocaine and benzoylecgonine exposure to the red swamp crayfish Procambarus clarkii

Cocaine (COC) and its main metabolite, the benzoylecgonine (BE), are the main illicit drugs measured in aquatic system worldwide, with concentrations up to hundreds of ng/L. Although their current environmental concentrations are low these molecules can induce adverse effects at sub-individual level in non-target organisms. In contrast, the information at individual and behavioral level are still scant. The present study aimed at investigating biochemical and behavioral effects induced by 14-days exposure to environmentally relevant concentrations (50 ng/L and 500 ng/L) of COC and BE towards Procambarus clarkii. At sub-individual level, the activity of antioxidant and detoxifying (superoxide dismutase - SOD, catalase - CAT, glutathione peroxidase - GPx and glutathione S-transferases - GST) enzymes, as well as the levels of lipid peroxidation (LPO), were measured as oxidative stress-related endpoints. We also measured the acetylcholinesterase (AChE) activity to check for neurotoxic effect of COC and BE. At individual level, the modulation of some behavioral tasks (i.e., response to external stimuli, changes in feeding activity and exploration of a new environment) were assessed. Although both COC and BE exposure did not induce an oxidative stress situation, a significant inhibition of AChE activity was noted, resulting in behavioral changes in crayfish exposed to COC only. Crayfish exposed to the higher COC concentration showed an increase in the boldness and a decrease in the feeding activity, suggesting that COC may act according to its psychotropic mode of action.

Toxicological Effects of Sewage Water on Chick Embryonic Development

For toxicity research, a total of 100 fertilized nonincubated eggs were used for this study. There were two trials in this experiment which were further divided into 2 phases based on a different days of sewage water treatment and observation days. In each trial, 50 eggs were used and divided into 5 groups. Group A, B, and C were treated with three different concentrations of pure and diluted sewage water (100%, 70%, and 30%), respectively. Control group D was given 0.3 ml saline solution (0.9% NaCl) and group E was uninjected. Different parameters such as the embryo's body weight, body length, forelimb length, hindlimb length, and head diameter were determined. In trial 1, eggs were treated with sewage water on 7th day of incubation and opened on 8th day (phase I) and 9th day (phase II). When the trial 1 (phase I) findings were compared to the control groups, it was observed that body weight, body length, forelimb length, and hindlimb length were highly statistically significant differences (p < 0.01), but the head diameter was not significant (p > 0.05). Phase II result showed embryo's head diameter was a highly statistically significant difference (p < 0.01), whereas forelimb length was significant (p < 0.05), and body weight, body length, and hindlimb length were nonsignificant (p > 0.05). In trial 2, eggs were treated with sewage water on 14th day of incubation and opened on 15th day (phase I) and 16th day (phase II). Results of 15th day showed a highly statistically significant (p < 0.01) difference in hindlimb length, while body weight, body length, forelimb length, and head diameter were nonsignificant (p > 0.05). Phase II of trial 2 showed that on 16th day, body weight, body length, forelimb length, hindlimb length, and head diameter showed a nonsignificant (p > 0.05) difference between experimental and control groups. Embryos were observed to be deforming on the 9th day (after 48 hours of exposure to sewage water). Other phases showed no signs of deformation. Except on 8th day of incubation, dose-related mortalities were present in experimental groups, while the control group showed no mortality.

Impact of COVID19 restrictions on organic micropollutants in wastewater treatment plants and human consumption rates

COVID19 pandemic and the consequent restrictions to constrain SARS-CoV-2 spreading produced several impacts on the worldwide population. The present study focused on 10 Organic Micropollutants (illicit drugs, pharmaceuticals including some antibiotics and caffeine) and aimed to assess: (1) if COVID19 pandemic restrictions affected the load of those contaminants released into the sewage network and consequently the removal achieved by the Wastewater Treatment Plants; (2) if pursuant to the COVID19 pandemic, there was a change in population consumption rates of the same compounds through the wastewater-based epidemiology (WBE) approach. Two full-scale wastewater treatment plants (WWTPs) located in Central Italy were chosen as case studies, which are distinguished by different characteristics of the catchment area and water treatment layouts. The study was based on a 2-years monitoring activity of the concentration of the above organic micropollutants, traditional water quality parameters (COD, TSS, nitrogen compounds, total phosphorous) and flow rate in the influent and effluent. The statistical analysis of the monitoring data showed an increase of the influent load of most of the organic micropollutants. A decrease from 22% to -18% of the median removal efficiency was observed for carbamazepine in the WWTP with the lower treatment capacity only. The other compounds were removed roughly at the same rate. The application of the WBE approach demonstrated an increase in the consumption rate of cocaine, trimethoprim, sulfamethoxazole, sulfadiazine, carbamazepine and above all caffeine during the COVID19 restrictions period. These results highlight that COVID19 pandemic affected people's lifestyle and habits also as far as drugs consumption is concerned, which in turn might have an impact on the treatment efficacy of plants and finally on the receiving water body quality. Therefore, it is mandatory to keep monitoring to improve knowledge and eventually to implement the required measures to address this new problem.

Cocaine esterase occurrence in global wastewater microbiomes and potential for biotransformation of novel psychoactive substances

The analysis of drugs in wastewater for forensic purposes has been constantly increasing and the investigation of the potential interaction between drugs or metabolites and sewage microbiota is important. The results demonstrated that cocaine esterase genes were widely distributed in 1142 global wastewater samples collected from 64 countries and linked to several bacterial species. In addition, in silico predictions indicated that carfentanil, 4F-MDMB-BINACA, 5F-MDMB-PICA, MDMB-4en-PINACA and mitragynine might also undergo microbial hydrolysis, in a similar fashion of cocaine degradation by cocaine esterase. In conclusion, it was demonstrated the microbial potential to hydrolyze drugs of abuse in wastewater environments, contributing to the critical evaluation of potential metabolites as biomarkers for microbial and human transformation of drugs in wastewater.

Illicit drug use in Reykjavik by wastewater-based epidemiology

Estimation of illicit drug use on a community level by wastewater-based epidemiology (WBE) is both an objective and reliable way to establish near real-time results. Wastewater samples were collected at eleven timepoints in Reykjavik from 2017 to 2020. The use of commonly abused illicit drugs in Iceland (amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA), cocaine, and cannabis) was estimated. Solid phase extraction and ultra-high performance liquid chromatography coupled to tandem mass spectrometry was used for analysis. Estimated amphetamine and methamphetamine use showed signs of an increase from 2017 to 2020 with amphetamine being the dominant stimulant on the market. MDMA use remained stable from 2017 to 2020. Results showed a large increase in cocaine use from 2017 to 2019 but interestingly, a marked decrease in 2020 during the COVID-19 pandemic. Cannabis use was stable from 2017 to 2019 but showed signs of an increase during the pandemic in 2020. Results by WBE corresponded with data based on two other indicators of drug use, seizure data and driving under the influence cases. Both temporal and spatial trends in illicit drug use were successfully estimated by using WBE, complimenting other indicators which provided a comprehensive picture of drug abuse in Reykjavik.

Performance- and image-enhancing drug use in the community: use prevalence, user demographics and the potential role of wastewater-based epidemiology

Performance- and image-enhancing drug (PIED) misuse is a significant public health issue. Currently, seizure data, surveys, anti-doping testing, and needle service provider data are used to estimate PIED use in populations. These methods are time consuming, single point-in-time measurements that often consist of small sample sizes and do not truly capture PIED prevalence. Wastewater-based epidemiology (WBE) has been used globally to assess and monitor licit and illicit drug consumption within the general community. This method can objectively cover large populations as well as specific subpopulations (gyms, music festivals, prisons), and has potential as a complementary monitoring method for PIED use. Information obtained through WBE could be used to aid public health authorities in developing targeted prevention and education programmes. Research on PIED analysis in wastewater is limited and presents a significant gap in the literature. The focus is on anabolic steroids, and one steroid alternative currently growing in popularity; selective androgenic receptor modulators. This encompasses medical uses, addiction, prevalence, user typology, and associated public health implications. An overview of WBE is described including its benefits, limitations and potential as a monitoring method for PIED use. A summary of previous work in this field is presented. Finally, we summarise gaps in the literature, future perspectives, and recommendations for monitoring PIEDs in wastewater.

Wastewater analysis for psychoactive substances at music festivals across New South Wales, Australia in 2019-2020

INTRODUCTION

Implementation of wastewater surveillance at music festivals has been limited to date. We aimed to use wastewater analysis and a self-report survey to determine the range of psychoactive substances being used during a music festival season in New South Wales, Australia.

METHODS

We sampled six single-day music festivals requiring a music festival license in New South Wales from March 2019 to March 2020; between 15% and 100% of portaloos (temporary, un-fixed toilet facilities) were sampled at each festival. Samples were screened for 98 psychoactive substances and/or their metabolites with results qualitatively expressed as detection frequencies for each substance at each festival and across all festivals. We compared these data with the results of surveys of self-reported drug use at four of the six festivals.

RESULTS

Festival attendance ranged from 6200 to 14,975 people. Amphetamine, cocaine, ketamine, methylone, MDMA, MDA, alprazolam, diazepam, etizolam, oxazepam and temazepam were found in almost all samples from all festivals. Ethylone, mephedrone and methcathinone were also found in over 50% of festivals. A norfentanyl (a fentanyl metabolite) and n-ethylpentylone were found at 2/6 and 1/6 festivals. No festival survey participant reported intentionally taking cathinones.

DISCUSSION

The detection frequency for cathinones was higher than expected relative to recent other data sources and this may represent adulteration or substitution. Similarly, the appearance of etizolam may be related to the use of counterfeit alprazolam. The detection of highly toxic substances such as N-ethylpentylone and norfentanyl may warrant public health alerts.

CONCLUSION

If provided close to real time, wastewater analysis at festivals could be complemented with information sources such as drug checking, on-site surveys, medical presentations and intelligence from peer networks to feed into early warning systems, public health alerts and peer-based harm reduction education during the festival season.

Monitoring SARS-CoV-2 in municipal wastewater to evaluate the success of lockdown measures for controlling COVID-19 in the UK

SARS-CoV-2 and the resulting COVID-19 pandemic represents one of the greatest recent threats to human health, wellbeing and economic growth. Wastewater-based epidemiology (WBE) of human viruses can be a useful tool for population-scale monitoring of SARS-CoV-2 prevalence and epidemiology to help prevent further spread of the disease, particularly within urban centres. Here, we present a longitudinal analysis (March-July 2020) of SARS-CoV-2 RNA prevalence in sewage across six major urban centres in the UK (total population equivalent 3 million) by q(RT-)PCR and viral genome sequencing. Our results demonstrate that levels of SARS-CoV-2 RNA generally correlated with the abundance of clinical cases recorded within the community in large urban centres, with a marked decline in SARS-CoV-2 RNA abundance following the implementation of lockdown measures. The strength of this association was weaker in areas with lower confirmed COVID-19 case numbers. Further, sequence analysis of SARS-CoV-2 from wastewater suggested that multiple genetically distinct clusters were co-circulating in the local populations covered by our sample sites, and that the genetic variants observed in wastewater reflected similar SNPs observed in contemporaneous samples from cases tested in clinical diagnostic laboratories. We demonstrate how WBE can be used for both community-level detection and tracking of SARS-CoV-2 and other virus' prevalence, and can inform public health policy decisions. Although, greater understanding of the factors that affect SARS-CoV-2 RNA concentration in wastewater are needed for the full integration of WBE data into outbreak surveillance. In conclusion, our results lend support to the use of routine WBE for monitoring of SARS-CoV-2 and other human pathogenic viruses circulating in the population and assessment of the effectiveness of disease control measures.

Wastewater Sample Site Selection to Estimate Geographically Resolved Community Prevalence of COVID-19: A Sampling Protocol Perspective

Wastewater monitoring for virus infections within communities can complement conventional clinical surveillance. Currently, most SARS-CoV-2 (severe acute respiratory syndrome coronavirus 2) clinical testing is voluntary and inconsistently available, except for a few occupational and educational settings, and therefore likely underrepresents actual population prevalence. Randomized testing on a regular basis to estimate accurate population-level infection rates is prohibitively costly and is hampered by a range of limitations and barriers associated with participation in clinical research. In comparison, community-level fecal monitoring can be performed through wastewater surveillance to effectively surveil communities. However, epidemiologically defined protocols for wastewater sample site selection are lacking. Herein, we describe methods for developing a geographically resolved population-level wastewater sampling approach in Jefferson County, Kentucky, and present preliminary results. Utilizing this site selection protocol, samples (n = 237) were collected from 17 wastewater catchment areas, September 8 to October 30, 2020 from one to four times per week in each area and compared to concurrent clinical data aggregated to wastewater catchment areas and county level. SARS-CoV-2 RNA was consistently present in wastewater during the studied period, and varied by area. Data obtained using the site selection protocol showed variation in geographically resolved wastewater SARS-CoV-2 RNA concentration compared to clinical rates. These findings highlight the importance of neighborhood-equivalent spatial scales and provide a promising approach for viral epidemic surveillance, thus better guiding spatially targeted public health mitigation strategies.

Wastewater analysis of psychoactive drugs: Non-enantioselective vs enantioselective methods for estimation of consumption

The consumption of licit and illicit psychoactive drugs (PAD) is ubiquitous in all communities and a serious public health problem. Measuring drug consumption is difficult but essential for health-care professionals, risk assessment and policymakers. Different sources of information have been used for a comprehensive analysis of drug consumption. Among them, Wastewater based epidemiology (WBE) emerged as an essential and complementary methodology for estimating licit and illicit drugs consumption. This methodology can be used for quantification of unchanged drugs or their human-specific metabolites in wastewater for estimation of consumption or screening of new PAD. Although some limitations are still being pointed out (e.g., estimation of the population size, use of suitable biomarkers or pharmacokinetics studies), the non-invasive and potential for monitoring real-time data on geographical and temporal trends in drug use have been showing its capacity as a routine and complementary tool. Chromatographic methods, both non-enantioselective and enantioselective are the analytical tools used for quantification of PAD in wastewaters and further estimation of consumption. Therefore, this manuscript aims to summarize and critically discuss the works used for wastewater analysis of PAD based on WBE using non-enantioselective and enantioselective methods for estimation of consumption. Non-enantioselective methods are among the most reported including for chiral PAD. Nevertheless, a trend has been seen towards the development of enantioselective methods as most PAD are chiral and determination of the enantiomeric fraction can provide additional information (e.g., distinction between consumption or direct disposal, or manufacture processes) and fulfill some WBE gaps.

Using Prescription and Wastewater Data to Estimate the Correction Factors of Atenolol, Carbamazepine, and Naproxen for Wastewater-Based Epidemiology Applications

The correction factor (CF) is a critical parameter in wastewater-based epidemiology (WBE) that significantly influences the accuracy of the final consumption estimates. However, most CFs have been derived from a few old pharmacokinetic studies and should be re-evaluated and refined to improve the accuracy of the WBE approach. This study aimed to review and estimate the CFs for atenolol, carbamazepine, and naproxen for WBE using the daily mass loads of those pharmaceuticals in wastewater and their corresponding dispensed prescription data in Australia. Influent wastewater samples were collected from wastewater treatment plants serving approximately 24% of the Australian population and annual national dispensed prescription data. The estimated CFs for atenolol and carbamazepine are 1.37 (95% CI: 1.17-1.66) and 8.69 (95% CI: 7.66-10.03), respectively. Due to significant over-the-counter sales of naproxen, a reliable CF could not be estimated based on prescription statistics. Using an independent dataset of 186 and 149 wastewater samples collected in an urban catchment in 2011 and 2012, WBE results calculated using the new CFs matched well with the dispensed data for atenolol and carbamazepine in the catchment area.

Evaluation of Illicit Drug Consumption by Wastewater Analysis Using Polar Organic Chemical Integrative Sampler as a Monitoring Tool

Illicit drug abuse is a worldwide social and health problem, and monitoring illicit drug use is of paramount importance in the context of public policies. It is already known that relevant epidemiologic information can be obtained from the analysis of urban residual waters. This approach, named wastewater-based epidemiology (WBE), is based on the measurement of specific markers, resulting from human biotransformation of the target drugs, as indicators of the consumption of the compounds by the population served by the wastewater treatment installation under investigation. Drug consumption estimation based on WBE requires sewage sampling strategies that express the concentrations along the whole time period of time. To this end, the most common approach is the use of automatic composite samplers. However, this active sampling procedure is costly, especially for long-term studies and in limited-resources settings. An alternative, cost-effective, sampling strategy is the use of passive samplers, like the polar organic chemical integrative sampler (POCIS). POCIS sampling has already been applied to the estimation of exposure to pharmaceuticals, pesticides, and some drugs of abuse, and some studies evaluated the comparative performances of POCIS and automatic composite samplers. In this context, this manuscript aims to review the most important biomarkers of drugs of abuse consumption in wastewater, the fundamentals of POCIS sampling in WBE, the previous application of POCIS for WBE of drugs of abuse, and to discuss the advantages and disadvantages of POCIS sampling, in comparison with other strategies used in WBE. POCIS sampling is an effective strategy to obtain a representative overview of biomarker concentrations in sewage over time, with a small number of analyzed samples, increased detection limits, with lower costs than active sampling. Just a few studies applied POCIS sampling for WBE of drugs of abuse, but the available data support the use of POCIS as a valuable tool for the long-term monitoring of the consumption of certain drugs within a defined population, particularly in limited-resources settings.

Occurrence, fate and mass loading of benzodiazepines and their transformation products in eleven wastewater treatment plants in Guangdong province, China

Benzodiazepines (BZDs) are one of the most widely prescribed psychoactive drugs, however their persistence in the receiving environment has raised great concerns about their potential ecological risks. Here we investigated the occurrence, fate and mass loading of 17 BZDs and their 3 transformation products in 11 wastewater treatment plants (WWTPs) in Guangdong province, China. A total of 10 BZDs and 1 transformation product were found in the WWTPs influents, effluents and excess sludge, with concentrations reaching up to 44.5 ng/L (clozapine), 27.1 ng/L (oxazepam) and 62.9 ng/g (clozapine), respectively. The overall removal efficiency varied widely from negative to complete removal in these 11 WWTPs. Mass balance analysis of two representative WWTPs (WWTP_A and WWTP_B) with different treatment processes showed that their removals were mainly attributed to the sludge adsorption and biodegradation/biotransformation. The total usage of detected BZDs was estimated to be 185 kg/y in Guangdong province, China, while the total emission was 143 kg/y. Based on sewage epidemiology method, the total back-estimated consumption and emissions of BZDs and their transformation products in one district of Guangzhou (WWTP_C service area) were 1012 mg/d/1000 people and 10.1 mg/d/1000 people, respectively. The findings from this study demonstrate the persistence of BZDs in WWTPs and also provide basis for further investigation into the potential ecological risks from this group of chemicals.

Analytical methodologies for the detection of SARS-CoV-2 in wastewater: Protocols and future perspectives

In March 2020 the World Health Organization announced a pandemic outbreak. Severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) is the causative pathogen for the coronavirus disease-19 (COVID-19) pandemic. The authorities worldwide use clinical science to identify infected people, but this approach is not able to track all symptomatic and asymptomatic cases due to limited sampling capacity of the testing laboratories. This drawback is eliminated by the Wastewater-Based Epidemiology (WBE) approach. In this review, we summarized the peer-reviewed published literature (available as of September 28, 2020), in the field of WBE. The commonly used steps (sampling, storage, concentration, isolation, detection) of the analytical protocols were identified. The potential limitations of each stage of the protocols and good practices were discussed. Finally, new methods for the efficient detection of SARS-CoV-2 were proposed.

Monitoring caffeine and nicotine use in a nationwide study in Italy using wastewater-based epidemiology

Smoking cigarettes and drinking coffee are common habits in today's society. However, it is not easy to get up-to-date information on smoking prevalence and caffeine consumption as it is usually obtained from population surveys. To overcome this limitation and complement epidemiological information, we employed wastewater-based epidemiology (WBE) to gain a picture of the consumption of cigarettes and caffeine per day per person in Italy. A nationwide study was conducted by measuring two urinary metabolites of nicotine (cotinine and trans-3'-hydroxycotinine) and a caffeine metabolite (1,7-dimethyluric acid) in untreated wastewater from 16 cities. The spatial profiles of use depended mostly on the specific population habits in each city, not on the geographical area or the population size. The patterns of consumption were stable over the week, except in Milan where the use of both substances decreased on Sundays, probably because there were no commuters. In Milan, the use of nicotine decreased from 2013 to 2015. There was a significant relationship between smoking and consumption of products containing caffeine (mainly coffee), thus in cities where more cigarettes were smoked, more caffeine was drunk. These results are generally in accordance with findings from epidemiological studies, but provide some additional local profiles of use and closely follow changes over the years. This information could be useful for healthcare professionals and policy-makers to monitor progress towards the reduction of prevalence in tobacco use, and set up new health campaigns.

Testing urban wastewater to assess compliance with prescription data through wastewater-based epidemiology: First case study in Italy

Sub-optimal adherence to pharmacological therapy is one of the main reasons for poor effectiveness, reducing the patient's quality of life and affecting health-care economics. This study investigated the possibility for a wastewater-based epidemiology approach to assess the overall adherence of a population to some pharmacological therapies in a defined area. We selected specific active ingredients and their main urinary metabolites (biomarkers) according to the best practice protocol available and we measured them for the first time in urban wastewater. We conducted this first case study in Italy, considering the whole country and two Italian regions by sampling for five days six cities from north to south. Liquid chromatography tandem mass spectrometry was used to measure the biomarkers in raw wastewater, developing and validating specific analytical methods. We used concentrations measured in influent wastewater, together with a careful review of the excretion profile of the active ingredients selected, to back-calculate consumption (measured consumptions - MC) which were then compared with consumptions calculated from medical prescriptions (expected consumptions - EC) reported annually by the Italian Medicine Agency. In general there was a rough correlation between MC and EC, with ratios sometimes close to unity and always within a 0.3-3.0 range. Interpretation of the results suffers some biases, which are case-by-case discussed in detail, but inclusion of measurements of the urinary metabolites together with the active ingredients gave a fuller understanding of the results.

Wastewater-based epidemiology to assess the occurrence of new psychoactive substances and alcohol consumption in Slovakia

Consumption of alcohol and new psychoactive substances (NPS) in a population or during special events (music festivals) is usually monitored through individual questionnaires, forensic and toxicological data, and drug seizures. However, consumption estimates have some biases due mostly to the unknown composition of drug pills for NPS and stockpiling for alcohol. The aim of this study was to evaluate for the first time the real use of alcohol and the occurrence of NPS in Slovakia by wastewater-based epidemiology (WBE). Urban wastewater samples were collected from nine Slovak cities over two years (2017-2018) and during three music festivals. The study included about 20% of the Slovak population and 50 000 festival attendees. The urinary alcohol biomarker ethyl sulfate (EtS) and thirty NPS were analyzed by liquid chromatography tandem mass spectrometry (LC - MS/MS). EtS concentrations were used for estimating the per capita alcohol consumption in each city. The average alcohol consumption in the selected cities and festivals in 2017-2018 ranged between 7 and 126 L/day/1000 inhabitants and increased during the weekends and music festivals. Five NPS belonging to the classes of synthetic cathinones (mephedrone, methcathinone, buphedrone and pentedrone) and phenethylamines (25-iP-NBoMe) were found in the low ng/L range. Methcathinone was the most frequently detected NPS, while the highest normalized mass load corresponded to mephedrone (3.1 mg/day/1000 inhabitants). Wastewater-based epidemiology can provide timely information on alcohol consumption and NPS occurrence at the community level that is complementary to epidemiology-based monitoring techniques (e.g. population surveys, police seizures, sales statistics).

Nanomaterial-based aptamer sensors for analysis of illicit drugs and evaluation of drugs consumption for wastewater-based epidemiology

The abuse of illicit drugs usually associated with dramatic crimes may cause significant problems for the whole society. Wastewater-based epidemiology (WBE) has been demonstrated to be a novel and cost-effective way to evaluate the abuse of illicit drugs at the community level, and has been used as a routine method for monitoring and played a significant role for combating the crimes in some countries, e.g. China. The method can also provide temporal and spatial variation of drugs of abuse. The detection methods mainly remain on the conventional liquid chromatography coupled with mass spectrometry, which is extremely sensitive and selective, however needs advanced facility and well-trained personals, thus limit it in the lab. As an alternative, sensors have emerged to be a powerful analytical tool for a wide spectrum of analytes, in particular aptamer sensors (aptasensors) have attracted increasing attention and could act as an efficient tool in this field due to the excellent characteristics of selectivity, sensitivity, low cost, miniaturization, easy-to-use, and automation. In this review, we will briefly introduce the context, specific assessment process and applications of WBE and the recent progress of illicit drug aptasensors, in particular focusing on optical and electrochemical sensors. We then highlight several recent aptasensors for illicit drugs in new technology integration and discuss the feasibility of these aptasensor for WBE. We will summarize the challenges and propose our insights and opportunity on aptasensor for WBE to evaluate community-wide drug use trends and public health.

Monitoring psychoactive substance use at six European festivals through wastewater and pooled urine analysis

The consumption of psychoactive substances is considered a growing problem in many communities. Moreover, new psychoactive substances (NPS) designed as (legal) substitutes to traditional illicit drugs are relatively easily available to the public through e-commerce and retail shops, but there is little knowledge regarding the extent and actual use of these substances. This study aims to gain new and complementary information on NPS and traditional illicit drug use at six music festivals across Europe by investigating wastewater and pooled urine. Samples were collected, between 2015 and 2018, at six music festivals across Europe with approximately 465.000 attendees. Wastewater samples were also collected during a period not coinciding with festivals. A wide-scope screening for 197 NPS, six illicit drugs and known metabolites was applied using different chromatography-mass spectrometric strategies. Several illicit drugs and in total 21 different NPS, mainly synthetic cathinones, phenethylamines and tryptamines, were identified in the samples. Ketamine and the traditional illicit drugs, such as amphetamine-type stimulants, cannabis and cocaine were most abundant and/or frequently detected in the samples collected, suggesting a higher use compared to NPS. The analyses of urine and wastewater is quick and a high number of attendees may be monitored anonymously by analysing only a few samples which allows identifying the local profiles of use of different drugs within a wide panel of psychoactive substances. This approach contributes to the development of an efficient surveillance system which can provide timely insight in the trends of NPS and illicit drugs use.

Assessment of human exposure to selected pesticides in Norway by wastewater analysis

Pesticides offer many benefits for humanity and agriculture, but at the same time pose a potential risk to human health because of their widespread use and high biological activity. Human biomonitoring (HBM) studies are the main tool to investigate human exposure to pesticides and other chemicals, but face limitations such as sampling biases, long time to complete and high costs. Wastewater-based epidemiology (WBE) is an alternative approach that is centered on the chemical analysis of biomarkers of (pesticide) exposure in urban wastewater. The present study used WBE to assess human exposure to selected classes of pesticides, triazines, pyrethroids and organophosphates, in Norway. Untreated wastewater samples were collected from four cities, covering approximately 20% of the Norwegian population. The highest population weighted mass loads (mg/day/1000 inhabitants) were for alkyl phosphates and the lowest for triazines. Some differences were observed for the two metabolites, 2-isopropyl-6-methyl-4-pyrimidinol (IMPY) and 3-(2,2-dichlorovinyl)-2,2-dimethyl-(1-cyclopropane) carboxylic acid (DCCA), which were higher in the rural city of Hamar. WBE figures were comparable with HBM findings for the specific metabolite of chlorpyrifos and chlorpyrifos methyl (3,5,6-trichloro-2-pyridinol; TCPY) but were different for the alkyl phosphates. Pyrethroid intake was calculated and was lower than the acceptable daily intake in all the cities, indicating low risk for human health. This is the most extensive WBE study performed to date to assess national human exposure to pesticides. This study demonstrated that WBE has the potential to be a useful complementary biomonitoring tool for assessing population-wide exposure to pesticides, overcoming some of the limitations of HBM.

Application of Molecularly Imprinted Polymers (MIP) and Flowing Atmospheric-Pressure Afterglow Mass Spectrometry (FAPA-MS) to Analysis of Nonsteroidal Anti-Inflammatory Drugs (NSAIDs)

In recent years, the rapid development of the pharmaceutical industry and the extensive and illicit use of painkillers have led to increased levels of nonsteroidal anti-inflammatory drugs (NSAIDs) in the environment. In view of the significant impact of NSAIDs on living organisms, including humans, their presence in the environment needs to be continuously monitored at trace levels. For this purpose, a combination of molecularly imprinted solid-phase extraction (MISPE) and HPLC-MS analysis is commonly used. MISPE has been utilized in direct, fast, and ecological analysis of drugs using a flowing atmospheric-pressure afterglow ion source for mass spectrometry (FAPA-MS). The new method was applied herein in the determination of naproxen, diclofenac, and ibuprofen. The linear dependence of the intensity of analytical signals on the amount of drugs is in the range of 0.2 μg to 1 g and the method detection limit (MDL) for all drugs is 0.2 μg in environmental samples. The new method also decreased the number of analytical stages, the time and cost of analysis, and the organic solvent consumption, besides being environmentally friendly.

Enantiomeric profiling of quinolones and quinolones resistance gene qnrS in European wastewaters

Wastewater-based epidemiology (WBE) was applied for the first time in seven cities across Europe with the aim of estimating quinolones consumption via the analysis of human urinary metabolites in wastewater. This report is also the first pan-European study focussed on the enantiomeric profiling of chiral quinolones in wastewater. By considering loads of (fluoro)quinolones in wastewater within the context of human stereoselective metabolism, we identified cities in Southern Europe characterised by both high usage and direct disposal of unused ofloxacin. In Northern European cities, S-(-)-ofloxacin loads were predominant with respect to R-(+)-ofloxacin. Much more potent, enantiomerically pure S-(-)-ofloxacin was detected in wastewaters from Southern European cities, reflecting consumption of the enantiomerically pure antibiotic. Nalidixic acid, norfloxacin and lomefloxacin were detected in wastewater even though they were not prescribed according to official prescription data. S,S-(-)-moxifloxacin and S,S-(-)-moxifloxacin-N-sulphate were detected in wastewater due to metabolism of moxifloxacin. For the first time, average population-normalised ulifloxacin loads of 22.3 and 1.5 mg day^-1 1000 people^-1 were reported for Milan and Castellón as a result of prulifloxacin metabolism. Enrichment of flumequine with first-eluting enantiomer in all the samples indicated animal metabolism rather than its direct disposal. Fluoroquinolone loads were compared with qnrS gene encoding quinolone resistance to correlate usage of fluoroquinolone and prevalence of resistance. The highest daily loads of the qnrS gene in Milan corresponded with the highest total quinolone load in Milan proving the hypothesis that higher usage of quinolones is linked with higher prevalence of quinolone resistance genes. Utrecht, with the lowest quinolones usage (low daily loads) had also one of the lowest daily loads of the qnrS gene. However, a similar trend was not observed in Oslo nor Bristol where higher qnrS gene loads were observed despite low quinolone usage.

A revised excretion factor for estimating ketamine consumption by wastewater-based epidemiology - Utilising wastewater and seizure data

The rate of drug excretion (excretion factor) is a critical parameter for monitoring drug consumption in the population by wastewater-based epidemiology (WBE). Previous studies have refined excretion factors for common illicit drugs, such as cocaine, amphetamine, methamphetamine, heroin, to improve the accuracy and reduce uncertainty in back-calculating consumption. Nevertheless, for ketamine, one of the most prevalent psychoactive substances, a careful review of its excretion factors has not been performed due to limited pharmacokinetic data. Here we review WBE studies and seizure data to refine and validate the excretion factors for ketamine and norketamine. The average ketamine/norketamine ratio in wastewater (5.36) was much higher than that found in urine (0.64), which means that the excretion factors derived only from pharmacokinetics data are not appropriate. Based on the comparison of the ratio between estimated consumptions of ketamine and methamphetamine by WBE with their corresponding ratio in official seizure data, a revised WBE excretion factor of 20% was proposed for ketamine following this review and applied to estimate the ketamine consumption in China. The revised estimates of ketamine consumption corresponded well with drug statistics. This suggests that the revised ketamine excretion factor is appropriate for estimating ketamine consumption by WBE. Systematic review of WBE studies is a suitable approach to refine the excretion factors for substances with inadequate pharmacokinetic data.

The Fourth-Revolution in the Water Sector Encounters the Digital Revolution

The so-called fourth revolution in the water sector will encounter the Big data and Artificial Intelligence (AI) revolution. The current data surplus stemming from all types of devices together with the relentless increase in computer capacity is revolutionizing almost all existing sectors, and the water sector will not be an exception. Combining the power of Big data analytics (including AI) with existing and future urban water infrastructure represents a significant untapped opportunity for the operation, maintenance, and rehabilitation of urban water infrastructure to achieve economic and environmental sustainability. However, such progress may catalyze socio-economic changes and cross sector boundaries (e.g., water service, health, business) as the appearance of new needs and business models will influence the job market. Such progress will impact the academic sector as new forms of research based on large amounts of data will be possible, and new research needs will be requested by the technology industrial sector. Research and development enabling new technological approaches and more effective management strategies are needed to ensure that the emerging framework for the water sector will meet future societal needs. The feature further elucidates the complexities and possibilities associated with such collaborations.

Urban wastewater analysis as an effective tool for monitoring illegal drugs, including new psychoactive substances, in the Eastern European region

The use of illicit drugs causes unquestionable societal and economic damage. To implement actions aimed at combating drug abuse, it is necessary to assess illicit drug consumption patterns. The purpose of this paper was to develop, optimize, validate and apply a procedure for determining new psychoactive substances (NPSs) and classic drugs of abuse and their main metabolites in wastewater samples by using solid phase extraction (SPE) and high-performance liquid chromatography coupled with tandem mass spectrometry (HPLC-MS/MS). Moreover, detailed validation of the procedure was conducted. The developed SPE–HPLC-MS/MS procedure (within the sewage-based epidemiology strategy) allowed for the simultaneous, selective, very sensitive, accurate (recoveries ≥ 80.1%) and precise (CV ≤ 8.1%) determination of new and classic psychoactive substances in wastewater samples. This study is characterized by new scientific elements, especially in terms of the freeze-thaw and post-preparative stability of the selected psychoactive substances. This is the first time that NPSs (mephedrone and ketamine), the main metabolites of heroin (6-acetylmorphine, 6-AM) and marijuana (11-nor-9-carboxy-Δ9-tetrahydrocannabinol, THC-COOH) have been detected and monitored in Poland. This study is also the first to corroborate the data available from the EMCDDA and EUROPOL report and indicates that the retail market for cocaine is expanding in Eastern Europe.

Evaluation of long-term detection trends of new psychoactive substances in pooled urine from city street portable urinals (London, UK)

AIMS

To evaluate the long-term trends of new psychoactive substance (NPS) detection in pooled urine samples collected across a city centre.

METHODS

Pooled urine samples from portable stand-alone urinals were collected on a monthly basis over 5.5 years (July 2013-December 2018) across a city centre. These were analysed using a high-performance liquid chromatography system, interfaced to a high-resolution accurate mass spectrometer. Data were processed against a database containing over 2000 drugs/metabolites including over 800 NPS.

RESULTS

In total, 44 NPS were detected with variation over time including cathinones (15, 34.1%), synthetic cannabinoids (8, 18.2%) and 21 (47.7%) other NPS. Since the introduction of the UK Psychoactive Substances Act (May 2016) cathinone detection has decreased with minimal detection over the last 4 months of the study. Synthetic cannabinoids were not detected on a regular basis until July 2016 with a subsequent variable detection frequency. There was a consistent, low level detection frequency of all other NPS throughout the study, but which appears to have increased alongside the decrease in cathinone detection.

CONCLUSION

Pooled urine analysis of samples taken from portable urinals in a city centre can be used as an effective monitoring tool to determine long-term trends in the use of NPS. The results of this study demonstrate the impact of the Psychoactive Substances Act and reflect the findings of population surveys and clinical studies. Triangulation of these data with other data sources will enable greater insight into the NPS phenomenon.

A comparison of trends in wastewater-based data and traditional epidemiological indicators of stimulant consumption in three locations

AIMS

To compare long-term trends in wastewater data with other indicators of stimulant use in three locations and to test the reliability of estimates based on 1 week of sampling.

DESIGN

Comparison of trends in quantities ('loads') of stimulants or their metabolites in wastewater with trends in other indicators of stimulant use (e.g. treatment, police, population survey data).

SETTING AND PARTICIPANTS

Populations in Oslo (Norway), South-East Queensland (Australia) and Eindhoven (the Netherlands).

MEASUREMENTS

Wastewater data were modelled for MDMA (3,4-methyl​enedioxy​methamphetamine), benzoylecgonine (a metabolite of cocaine), amphetamine and methamphetamine in Oslo; benzoylecgonine in Eindhoven; and methamphetamine in South-East Queensland. Choice of stimulants modelled in each region was primarily determined by availability of useable data.

FINDINGS

In Oslo, wastewater data, driving under the influence of drugs statistics and seizure data all suggested increasing MDMA use between 2009 and 2017. In South-East Queensland, there was an estimated 31.1% [95% confidence interval (CI) = 29.4-32.9%] annual increase in daily loads of methamphetamine in wastewater between 2009 and 2016, compared with a 14.1% (95% CI = 10.9-17.3%) annual increase in seizures. Some of the increase in wastewater can be explained by increased purity. In Eindhoven, there was no evidence of a change in cocaine consumption from wastewater, but a reduction was observed in numbers in treatment for cocaine use from 2012 to 2017. In approximately half the cases examined in Oslo, credible intervals around estimates of annual average loads from a regression model versus estimates based on a single week of sampling did not overlap.

CONCLUSIONS

Long-term trends in loads of stimulants in wastewater appear to be broadly consistent with trends in other indicators of stimulant use in three locations. Wastewater data should be interpreted alongside epidemiological indicators and purity data. One week of wastewater sampling may not be sufficient for valid inference about drug consumption.

Wastewater-based epidemiology for tracking human exposure to mycotoxins

Mycotoxins are among the compounds of most concern for human health because of their common presence in food and their proven toxicity for human health. Human biomonitoring (HBM) studies, foodstuff analysis and dietary surveys are usually used to assess human exposure, but they are costly and time-consuming. Wastewater-based epidemiology (WBE) can complement the established exposure monitoring tools. The aim of this study was to develop a new WBE application for assessing human exposure to mycotoxins by measuring specific biomarkers in raw wastewater. Eleven substances were analysed by liquid chromatography-tandem mass spectrometry in wastewater from four cities in Italy and Spain. Only deoxynivalenol (DON) and fumonisines were found, DON being the most abundant, in accordance with HBM studies. DON intake, back-calculated by WBE, was lower than the established Health-Based Guidance values, indicating moderate exposure in the population, with no risks for human health. WBE intake estimates were very close to those reported in HBM studies, validating WBE for estimating DON intake in the population. This study describes a promising WBE approach to complement HBM studies and assess the human intake of specific classes of mycotoxins, thus helping to identify risks for human health.

Seasonal monitoring of cocaine and benzoylecgonine in a subtropical coastal zone (Santos Bay, Brazil)

Illicit drugs and their metabolites represent a new class of emerging contaminants. These substances are continuously discharged into wastewater which have been detected in the aquatic environment in concentrations ranging from ng.L^-1 to μg.L^-1. Our study detected the occurrence of cocaine (COC) and benzoylecgonine (BE) in a subtropical coastal zone (Santos Bay, SP, Brazil) within one year. Water samples (surface and bottom) were collected from the Santos Submarine Sewage Outfall (SSOS) area. COC and BE were measured in the samples using ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-ESI-MS/MS). Concentrations ranged from 12.18 to 203.6 ng.L^-1 (COC) and 8.20 to 38.59 ng.L^-1 (BE). Higher concentrations of COC were observed during the end of spring, following the population increase at summer season. COC and its metabolite occurrence in this coastal zone represent a threat to coastal organisms.

Quantification and Multidrug Resistance Profiles of Vancomycin-Resistant Enterococci Isolated from Two Wastewater Treatment Plants in the Same Municipality

Wastewater treatment plants (WWTPs) are points of control for the environmental dissemination of antimicrobial resistant bacteria. Vancomycin-resistant enterococci (VRE) were used as indicators of antimicrobial resistance (AMR) in two WWTPs (biologically aerated filter (BAF) and conventional activated sludge (CAS)) in the same municipality. The removal and abundance of enterococci and VRE as well as the species and antimicrobial resistance profiles of VRE were assessed. Enterococci and VRE from the primary and final effluents were enumerated. Results were assessed from an ecological context. VRE was not selected for by either WWTP but the BAF system outperformed the CAS system for the removal of enterococci/VRE. Enterococcus faecalis (n = 151), E. faecium (n = 94) and E. casseliflavus/E. gallinarum (n = 59) were the dominant VRE species isolated. A decrease in levofloxacin resistance in enterococci was observed in the BAF WWTP. An increase in nitrofurantoin resistant (p < 0.001) and a decrease in quinupristin/dalfopristin (p = 0.003) and streptomycin (p = 0.022) resistant enterococci were observed in the CAS WWTP, corresponding to a shift of VRE from E. faecalis to E. faecium. Wastewater treatment processes can be managed to limit the dissemination of antimicrobial resistance determinants into the surrounding environment.

Flexible high resolution-mass spectrometry approach for screening new psychoactive substances in urban wastewater

The number of new psychoactive substances (NPS) on the recreational drug market has increased rapidly in the last years, creating serious challenges for public health agencies and law enforcement authorities. Epidemiological surveys and forensic analyses to monitor the consumption of these substances face some limitations for investigating their use on a large scale in a shifting market. The aim of this work was to develop a comprehensive and flexible screening approach for assessing the presence of NPS in urban wastewater by liquid chromatography-high resolution mass spectrometry (LC-HRMS). Almost 200 substances were selected as "priority NPS" among those most frequently and recently reported by the Early Warning Systems (EWS) of different agencies and were included in the screening. Wastewater samples were collected from several cities all over Europe in 2016 and 2017, extracted using different solid-phase cartridges and analysed by LC-HRMS. The screening workflow comprised three successive analytical steps and compounds were identified and confirmed following specific criteria from the current guidelines. Thirteen NPS were identified at different confidence levels by using analytical standards or information from libraries and literature, and about half of them were phenethylamines. As far as we know, this is the first time that four of them (i.e. 3,4-dimethoxy-α-pyrrolidinovalerophenone, para-methoxyamphetamine, 2-phenethylamine and α-methyltryptamine) have been found in urban wastewater. The proposed screening approach was successfully applied in the largest NPS European wastewater monitoring, providing an innovative and easily adapted procedure for investigating NPS. In the light of current challenges and specific future research issues, this approach may complement epidemiological information and help in establishing measures for public health protection.

Impact of meteorological and social events on human-excreted contaminant loads in raw wastewater: From daily to weekly dynamics

The temporal dynamics of the wastewater influent loads of 25 drug target residues (DTR, both pharmaceuticals and illicit drugs) was assessed during 84 consecutive days. This monitoring scale enables longer temporal patterns than weekday/weekend patterns to be explored. In this study, we focus on day to day variations and the potential statistical correlation of each DTR analyzed in order to better understand the potential forcings that lead to the load variation of DTRs (alone or in clusters). The weekly patterns based on the weekly loads of DTRs were also analyzed and the impact of social and meteorological events on their variations was investigated. Two cold events occurred during the monitoring period and were associated with the highest loads of analgesics and non-steroidal anti-inflammatory drugs, as well as the lowest loads of stimulants. During the Easter holidays, a significant decrease in some year-long medication as well as analgesics was found, consistent with the demographic decrease within the catchment during this period. Lastly, a good correlation between the academic calendar and the loads of stimulants was found, emphasizing the overrepresentation of students in the consumption of recreational drugs. This study furnishes new insights in order to better understand the variations in DTR loads in wastewater influents, beyond the weekday/weekend pattern and the seasonal effect. Further investigations remain necessary, especially a real-time monitoring of the population figures within the catchment in order to improve our understanding of these results.

Wastewater analysis for nicotine, cocaine, amphetamines, opioids and cannabis in New York City

According to current surveys and overdoses data, there is a drug crisis in the USA. Wastewater-based epidemiology (WBE) is an evolving discipline that analyses wastewater samples to detect drugs and metabolites to estimate drug consumption in a certain community. This study demonstrates how drug relative presence could be tracked by testing wastewater, providing real-time results, in different boroughs in New York City throughout 1 year. We developed and fully validated two analytical methods, one for 21 drugs and metabolites, including nicotine, cocaine, amphetamines, opioids and cannabis markers; and another for the normalization factor creatinine. Both methods were performed by liquid chromatography tandem mass spectrometry (LC-MS/MS) using positive electrospray ionization, achieving a limit of quantification of 5–10 ng/L for drugs and metabolites, and 0.01 mg/L for creatinine. These methods were applied to 48 one-time grab wastewater samples collected from six wastewater treatment plants in New York City (Manhattan, The Bronx, Queens and Brooklyn), eight different times throughout 2016, before and after major holidays, including Memorial Day, 4th of July, Labour Day and New Year’s. In this study, the drug group normalized concentrations present in the wastewater samples, in decreasing order, were cocaine, nicotine, opioids, cannabis and amphetamines. When looking at individual compounds, the one with the highest normalized concentration was benzoylecgonine (BE), followed by cotinine, morphine and 11-nor-9-carboxy-tetrahydrocannabinol (THCCOOH). To estimate community use, these concentrations were multiplied by the corresponding correction factor, and the most present were THCCOOH, followed by BE, cotinine and morphine. When comparing the treatment plants by drug group (nicotine, cocaine, amphetamines, opioids and cannabis), samples collected from The Bronx had the highest normalized concentrations for nicotine, cocaine and opioids; The Bronx and Manhattan for cannabis; and Manhattan and Queens for amphetamines. In most of the cases, no effect due to holiday was observed. This study provides the first snapshot of drug use in New York City and how that changes between key calendar dates employing wastewater analysis.