Illicit and pharmaceutical drug consumption estimated via wastewater analysis. Part B: placing back-calculations in a formal statistical framework

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.

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.

Pharmaceutical and Recreational Drug Usage Patterns during and Post COVID-19 Determined by Wastewater-Based Epidemiology

Wastewater-based epidemiology (WBE) was applied to evaluate the consumption trends of pharmaceuticals (i.e., antibiotics, non-steroidal anti-inflammatory drugs, antiepileptics, antihypertensives, and others), as well as recreational drugs (caffeine, alcohol, and nicotine), in Latvia from December 2020 to July 2023. The time period covers both the COVID-19 pandemic and the post-pandemic periods; therefore, the impact of the implemented restrictions and the consequences of the illness in terms of the usage of pharmaceuticals thereon were investigated. Additionally, the seasonality and impact of the seasonal flu and other acute upper respiratory infections were studied. The results revealed that the pandemic impacted the consumption of alcohol, nicotine, and caffeine, as well as several pharmaceuticals, such as antihypertensives, antidepressants, psychiatric drugs, and the painkiller ibuprofen. The findings suggest that the imposed restrictions during the pandemic may have had a negative effect on the population's health and mental well-being. Distinct seasonal trends were discovered in the consumption patterns of caffeine and alcohol, where lower use was observed during the summer. The seasonal consumption trends of pharmaceuticals were discovered in the case of antibiotics, the antiasthmatic drug salbutamol, and the decongestant xylometazoline, where higher consumption occurred during colder seasons.

Wastewater profiling of illicit drugs, an estimation of community consumption: A case study of eThekwini Metropolitan Municipality, South Africa

Estimation of community-wide consumption of illicit drugs through wastewater analysis is a new concept in Africa although widely applied in developed nations as wastewater-based epidemiology (WBE). It is an important tool that can be used in understanding supply and demand patterns of illicit drug use on a local, national, and international scale. Information on illicit drug use is currently limited in Africa, because of a lack of monitoring structures by governments and financial constraints. This study hopes to bridge that gap by contributing to Africa's baseline information on illicit drug use. This study provides the first application of wastewater analysis to quantitatively evaluate daily illicit drug use in the eThekwini Metropolitan Municipality of KwaZulu-Natal Province of South Africa by quantifying the major urinary excreted metabolites, called drug target residues (DTRs), in raw wastewater from four major wastewater treatment plants (WWTPs) sampled for a week. The results showed that cocaine was the dominant illicit drug consumed in the catchment followed by amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine and 3,4-methylenedioxyamphetamine, with a per capita use of 360-3000 mg day-1 1000 inh-1, 47-800 mg day-1 1000 inh-1, 19-120 mg day -1 1000 inh-1, not detected (ND) to 4.9 mg day-1 1000 inh-1, and ND to 410 g day-1 1000 inh-1 respectively. The weekly usage patterns between the four WWTPs differed probably due to the lifestyle of the populace serving the different WWTPs. These results provide useful data on illicit drug use in eThekwini that can be utilised by public health agencies to implement suitable response strategies.

Understanding and managing uncertainty and variability for wastewater monitoring beyond the pandemic: Lessons learned from the United Kingdom national COVID-19 surveillance programmes

The COVID-19 pandemic has put unprecedented pressure on public health resources around the world. From adversity, opportunities have arisen to measure the state and dynamics of human disease at a scale not seen before. In the United Kingdom, the evidence that wastewater could be used to monitor the SARS-CoV-2 virus prompted the development of National wastewater surveillance programmes. The scale and pace of this work has proven to be unique in monitoring of virus dynamics at a national level, demonstrating the importance of wastewater-based epidemiology (WBE) for public health protection. Beyond COVID-19, it can provide additional value for monitoring and informing on a range of biological and chemical markers of human health. A discussion of measurement uncertainty associated with surveillance of wastewater, focusing on lessons-learned from the UK programmes monitoring COVID-19 is presented, showing that sources of uncertainty impacting measurement quality and interpretation of data for public health decision-making, are varied and complex. While some factors remain poorly understood, we present approaches taken by the UK programmes to manage and mitigate the more tractable sources of uncertainty. This work provides a platform to integrate uncertainty management into WBE activities as part of global One Health initiatives beyond the pandemic.

Wastewater-based epidemiology for illicit drugs: A critical review on global data

Illicit drug use is complex, hidden and often highly stigmatized behaviour, which brings a vast challenge for drug surveillance systems. Drug consumption can be estimated by measuring human excretion products in untreated wastewater, known as wastewater-based epidemiology (WBE). Over the last decade, the application of wastewater-based epidemiology to monitor illicit drug loads increased and WBE is currently applied on a global scale. Studies from over the globe are evaluated with regard to their sampling method, analytical accuracy and consumption calculation, aiming to further reduce relevant uncertainties in order to make reliable comparisons on a global level. Only a limited number is identified as high-quality studies, so further standardization of the WBE approach for illicit drugs is desired especially with regard to the sampling methodology. Only a fraction of the reviewed papers explicitly reports uncertainty ranges for their consumption data. Studies which had the highest reliability are recently published, indicating an improvement in reporting WBE data. Until now, WBE has not been used in large parts of Africa, nor in the Middle East and Russia. An overview of consumption data across the continents on commonly studied drugs (cocaine, MDMA, amphetamine and methamphetamine) is provided. Overall, high consumption rates are confirmed in the US, especially for cocaine and methamphetamine, while relatively low illicit drug consumption is reported in Asia.

Comparison of community illicit drug use in 11 cities of Turkey through wastewater-based epidemiology

Wastewater-based epidemiology (WBE) is an ever-increasing discipline that enables researchers to track near-real-time data concerning the recreational use of illicit drugs. Community illicit drug use was estimated in eleven Turkish cities, using eighteen wastewater treatment plants, representing the metropolitan cities and rural areas with different socio-demographic characteristics. In this study, 24-h composite influent wastewater samples were collected for 1 week per season between March 2019 and December 2019. Heroin, amphetamine, methamphetamine, ecstasy, cocaine, and marijuana were covered as illicit drugs in this study. Solid-phase extraction, LC-MS/MS separation, identification, and quantification were used as the analytical methods. Overall results indicate that both cocaine and MDMA usage increased in all cities on weekends. More specifically, it was observed that the average amount of cocaine use regarding 11 cities was 14.7 mg/1000 person/day, while figures for other substances are as follows: 9.5 for amphetamine, 34.5 for methamphetamine, 38.4 for MDMA, 42.2 for heroin, and lastly 5412 mg/1000p/day for marijuana. This study holds the position of being the most comprehensive one conducted, considering spatial and temporal datasets on illicit drug consumption obtained via WBE in Turkey.

Monitoring drug consumption in Innsbruck during coronavirus disease 2019 (COVID-19) lockdown by wastewater analysis

The coronavirus disease 2019 (COVID-19) has developed into a serious pandemic with millions of cases diagnosed worldwide. To fight COVID-19 pandemic, over 100 countries instituted either a full or partial lockdown, affecting billions of people. In Tyrol, first lockdown measures were taken on 10 March 2020. On 16 March 2020, a curfew went into force which ended on 1 May 2020. On 19 March 2020, Tyrol as a whole was placed in quarantine which ended on 7 April 2020. The governmental actions helped reducing the spread of COVID-19 at the cost of significant effects on social life and behaviour. Accordingly, to provide a comprehensive picture of the population health status not only input from medical and biological sciences is required, but also from other sciences able to provide lifestyle information such as drug use. Herein, wastewater-based epidemiology was used for studying temporal trends of licit and illicit drug consumption during lockdown and quarantine in the area of the Tyrolean capital Innsbruck (174,000 inhabitants). On 35 days between 12 March 2020 and 15 April 2020, loads of 23 markers were monitored in wastewater. Loads determined on 292 days between March 2016 and January 2020 served as reference. During lockdown, changes in the consumption patterns of recreational drugs (i.e. cocaine, amphetamine, 3,4-methylenedioxymethamphetamine, methamphetamine, and alcohol) and pharmaceuticals for short-term application (i.e. acetaminophen, codeine, and trimethoprim) were detected. For illicit drugs and alcohol, it is very likely that observed changes were linked to the shutdown of the hospitality industry and event cancelation which led to a reduced demand of these compounds particularly on weekends. For the pharmaceuticals, further work will be necessary to clarify if the observed declines are indicators of improved population health or of some kind of restraining effect that reduced the number of consultations of medical doctors and pharmacies.

Spatial analysis of metformin use compared with nicotine and caffeine consumption through wastewater-based epidemiology in China

Monitoring the consumption of pharmaceuticals and licit drugs is important for assessing the needs of public health owing to the impact on individuals as well as society. The present work applied wastewater-based epidemiology to profile the spatial patterns of metformin, nicotine, and caffeine use and their correlations. Influent wastewater samples were collected from 27 wastewater treatment plants in 22 typical Chinese cities that covered all geographic regions of the country. The consumption of metformin ranged from 0.02 g/d/1000 inh to 8.92 g/d/1000 inh, whereas caffeine and nicotine consumption ranged from 4.33 g/d/1000 inh to 394 g/d/1000 inh and 0.17 g/d/1000 inh to 1.88 g/d/1000 inh, respectively. There were significant regional differences in the consumption of caffeine, with the highest consumption in East China and the lowest consumption in Northeast China. The consumption and concentration of caffeine were related to the gross domestic product and per capita disposable income of urban residents, respectively. There was a correlation between the concentrations of caffeine and cotinine (a nicotine metabolite), thereby indicating that individuals that use one of these substances are likely to use the other substance. A significant relationship was found between the concentration of metformin and cotinine, thereby implying that the use of tobacco may be correlated with type 2 diabetes. Co-analysis of these substances in wastewater may provide a more accurate picture of substance use situations within different communities and provide more information on human health, human behavior, and the economy. This report describes the newest study related to the consumption of metformin among the general population in China.

High-throughput multi-residue quantification of contaminants of emerging concern in wastewaters enabled using direct injection liquid chromatography-tandem mass spectrometry

A rapid quantitative method for 135 contaminants of emerging concern (CECs) in untreated wastewater enabled with direct injection liquid chromatography-tandem mass spectrometry is presented. All compounds were analysed within 5 min on a short biphenyl cartridge using only 10 μL of filtered sample per injection. Up to 76 compounds were monitored simultaneously during the gradient (including mostly two transitions per compound and stable isotope-labelled analogues) while yielding >10 data points per peak. Evaluation of seven solid phase extraction sorbents showed no advantage for wastewater matrix removal. Excellent linearity, range, accuracy and precision was achieved for most compounds. Matrix effects were <11 % and detection limits were <30 ng L^-1 on average. Application to untreated wastewater samples from three wastewater treatment works in the UK, USA and Mexico, enabled quantification of 56 compounds. Banned and EU 'watch-list' substances are critically discussed, including pesticides, macrolide antibiotics, diclofenac, illicit drugs as well as multiple pharmaceuticals and biocides. This high-throughput method sets a new standard for the speedy and confident determination of over a hundred CECs in wastewater at the part-per-trillion level, as demonstrated by performing over 260 injections per day.

A global systematic review and meta-analysis on illicit drug consumption rate through wastewater-based epidemiology

Wastewater-based epidemiology (WBE) is a complementary, well-established comprehensive, cost-effective, and rapid technique for monitoring of illicit drugs used in a general population. This systematic review and meta-analysis is the first to estimate the rank and consumption rate of illicit drugs through WBE studies. In the current study, the related investigations regarding the illicit drug consumption rate based on WBE were searched among the international databases including Scopus, PubMed, Science direct, Google scholar, and local database, Magiran from 2012 up to May 2019. The illicit drug consumption rate with 95% confidence intervals was pooled between studies by using random effect model. The heterogeneity was determined using I² statistics. Also, subgroup analyses were conducted to examine the possible effects of year and location of studies on observed heterogeneity. Meta-analysis of 37 articles indicates that the overall rank order of illicit drugs according to their pooled consumption rate can be summarized as tetrahydrocannabinol or cannabis (7417.9 mg/day/1000 people) > cocaine (655.7 mg/day/1000 people) > morphine (384.9 mg/day/1000 people) > methamphetamine (296.2 mg/day/1000 people) > codeine (222.7 mg/day/1000 people) > methadone (200.2 mg/day/1000 people) > 3,4-methylenedioxymethamphetamine (126.3 mg/day/1000 people) > amphetamine (118.2 mg/day/1000 people) > 2-ethylidene-1,5-dimethyl-3, 3-diphenylpyrrolidine (33.7 mg/day/1000 people). The pooled level rate was 190.16 mg/day/1000 people for benzoylecgonine (main urinary cocaine metabolite), 137.9 mg/day/1000 people for 11-nor-9-carboxy-delta9-tetrahydrocannabinol (main metabolite of cannabis), and 33.7 mg/day/1000 people for 2-ethylidene-1,5-dimethyl-3, 3-diphenylpyrrolidine (main metabolite of methadone). The I² values for all selected drugs were 100% (P value < 0.001). The results of year subgroup indicated that the changes of heterogeneity for all selected drugs were nearly negligible. The heterogeneity within studies based on continents subgroup just decreased in America for drugs like 11-nor-9-carboxy-delta9-tetrahydrocannabinol (I² = 24.4%) and benzoylecgonine (I² = 94.1%). The outcome of this meta-analysis can be used for finding the illicit drugs with global serious problem in view of consumption rate (i.e., cannabis and cocaine) and helping authorities to combat them.

Implementation of environmental surveillance for SARS-CoV-2 virus to support public health decisions: Opportunities and challenges

Analysing wastewater can be used to track infectious disease agents that are shed via stool and urine. Sewage surveillance of SARS-CoV-2 has been suggested as a tool to determine the extent of COVID-19 in cities and serve as an early warning for (re-)emergence of SARS-CoV-2 circulation in communities. The focus of this review is on the strength of evidence, opportunities and challenges for the application of sewage surveillance to inform public health decision making. Considerations for undertaking sampling programs are reviewed including sampling sites, strategies, sample transport, storage and quantification methods; together with the approach and evidence base for quantifying prevalence of infection from measured wastewater concentration. Published SARS-CoV-2 sewage surveillance studies (11 peer reviewed and 10 preprints) were reviewed to demonstrate the current status of implementation to support public health decisions. Although being very promising, a number of areas were identified requiring additional research to further strengthen this approach and take full advantage of its potential. In particular, design of adequate sampling strategies, spatial and temporal resolution of sampling, sample storage, replicate sampling and analysis, controls for the molecular methods used for the quantification of SARS-CoV-2 RNA in wastewater. The use of appropriate prevalence data and methods to correlate or even translate SARS-CoV-2 concentrations in wastewater to prevalence of virus shedders in the population is discussed.

Review on the occurrence and biological effects of illicit drugs in aquatic ecosystems

Illicit drugs (IDs) and their metabolites are recognized as contaminants of emerging concern. After consumption, illicit drugs are partially metabolized and excreted unchanged in urine and feces or as active metabolites reaching wastewater treatment plants (WWTPs). Furthermore, most WWTPs are insufficient in the treatment of effluents containing IDs, which may be released into aquatic ecosystems. Once in the water or sediment, these substances may interact and affect non-target organisms and some evidences suggest that illicit drugs may exhibit pseudo-persistence because of a continuous environmental input, resulting in long-term exposure to aquatic organisms that may be negatively affected by these biologically active compounds. We reviewed the literature on origin and consumption, human metabolism after consumption, aquatic occurrences, and toxicity of the major groups of illicit drugs (opioids, cannabis, synthetic drugs, and cocaine). As a result, it could be concluded that illicit drugs and their metabolites are widespread in diverse aquatic ecosystems in levels able to trigger sublethal effects to non-target organisms, besides to concentrate in seafood. This class of emerging contaminants represents a new environmental concern to academics, managers, and policymakers, whose would be able to assess risks and identify proper responses to reduce environmental impacts.

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.

Prevalence of illicit and prescribed neuropsychiatric drugs in three communities in Kentucky using wastewater-based epidemiology and Monte Carlo simulation for the estimation of associated uncertainties

A cost-effective alternative approach capable of determining the prevalence of substance use in communities can complement the existing efforts of combating drug abuse and addiction. In this study, the prevalence of 10 illicit and 19 prescribed psychoactive drugs of potential abuse was determined utilizing wastewater-based epidemiology, and compared in two adjoined urban communities and a rural community. This is the first application of the Monte Carlo simulation method to account multiple uncertainties and propagation of errors associated with the individual parameter of wastewater based epidemiological estimations in the U.S. A significantly higher prevalence of cocaine [3830 (mean difference, MD: 2960) mg/d/1000 people] was found in the central business district while the per-capita consumption rates of amphetamine [738 (MD: 338) mg/d/1000 people] and methamphetamine [1660 (MD: 629) mg/d/1000 people] were higher in a rural community. Among narcotics, the per-capita consumption rate of fentanyl and morphine was significantly higher in urban communities while codeine, hydrocodone, hydromorphone, and buprenorphine were dominant in a rural community. The significantly higher prevalence of buprenorphine (˜20-30 folds), oxycodone (˜2-3 folds), and alprazolam (˜2-3 folds) determined in these communities compared to the conventional estimates based on the electronically reported prescriptions and drug-related inpatient hospitalizations suggest the abuse of these drugs.

Gold nanoparticles modified exfoliated graphite electrode as electrochemical sensor in the determination of psychoactive drug

The use and abuse of prescription and illicit drugs are on the rise worldwide and as a result residue of these drugs and their metabolites are continually being disposed into the environment through sewage system and other means. Therefore, this paper reports on the development of a cost-effective, simple and sensitive approach that involved the fabrication of an electrochemical sensor from exfoliated graphite (EG) and gold nanoparticles (AuNPs) for the detection of selected psychoactive drugs in water. The fabricated electrochemical sensor was characterized using scanning electron microscopy coupled with energy dispersive X-ray spectroscopy (SEM-EDS) to ascertain its surface morphology characteristics and cyclic voltammetry (CV) for ascertaining the redox potential peak. The EG-AuNPs sensor was able to detect cocaine in water with limit of detection (LOD) and limit quantification (LOQ) of 0.82 and 2.74 µg/L, respectively under the pH of 12.25. The sensor was extended on other psychoactive drugs (methylphenidate, amphetamine and heroin) and one metabolite (6-acetylmorphine) to examine its applicability. The drugs were distinctively detected, and thus making EG-AuNPs electrode a possible alternative sensor for electrochemical detection of psychoactive drugs and their metabolites in synthetic and real water samples.

Human exposure of bisphenol A and its analogues: understandings from human urinary excretion data and wastewater-based epidemiology

This work evaluated human exposure to bisphenol A (BPA) and its analogues based on human urinary excretion data and wastewater-based epidemiology (WBE). The results showed that the world's average human daily intake ranked from high to low is in order of bisphenol A (BPA), bisphenol F (BPF), bisphenol S (BPS), bisphenol P (BPP), bisphenol AP (BPAP), bisphenol B (BPB), bisphenol Z (BPZ), and bisphenol AF (BPAF), and their corresponding human daily intakes are 2.53, 0.68, 0.60, 0.41, 0.36, 0.29, 0.24, and 0.06 μg/p/day, respectively. BPA is clearly the dominant bisphenol for human exposure. However, the results also showed that humans have been widely exposed to BPA analogues as well. Many BPA analogues showed similar estrogenic activities to those of BPA; therefore, the adverse effects of BPA and its analogues on humans should be comprehensively evaluated. The nominal exposure levels obtained based on wastewater-based epidemiology ranked high to low are in order of BPA (513.73 μg/p/day), BPF (10.20 μg/p/day), BPS (5.21 μg/p/day), BPP (1.15 μg/p/day), BPZ (0.66 μg/p/day), BPB (0.61 μg/p/day), BPAF (0.58 μg/p/day), and BPAP (0.35 μg/p/day). The world's human average daily intakes of BPA and its analogues are only 0.5-47.9% of the intakes of their corresponding human nominal exposures. This study suggests that other sources rather human excretions are important origins in municipal wastewater, which indicates that the WBE method based on parent compounds is inappropriate for evaluations of human daily intakes of BPA and its analogues, neither for other industrial compounds that have multiple important sources. Three main important sources of BPA and its analogues in municipal wastewater are likely effluents of industrial wastewater, discharges of hospital wastewater, and landfill leachates. To decrease discharges of BPA and its analogues to the natural environment, any mixing of industrial and hospital wastewater as well as landfill leachates in municipal wastewater is not favorable.

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.

Assessment of drugs of abuse in a wastewater treatment plant with parallel secondary wastewater treatment train

In this study, 24-hour composite wastewater samples were collected from a wastewater treatment plant of New Zealand with parallel secondary treatment units. The aim was to investigate the occurrence, removal, and consumption of 13 drugs of abuse (DOAs) including illicit drugs, alcohol, nicotine, and their metabolites. The filtered samples were analysed through direct injection on LC-MS/MS. Ethyl sulfate, one of the major metabolites of alcohol, was detected at the highest concentration (mean = 8300 ng/L) in wastewater influent. The mean concentrations of methamphetamine and hydroxycotinine in the influent were found to be 935 ng/L and 5000 ng/L, respectively. Amphetamine (383 ng/L) and cocaine (286 ng/L) were detected at the highest concentrations in the effluent. The removal efficiency of the treatment plant varied for DOAs: >99% for morphine, ethyl sulfate, and hydroxycotinine and <50% for methadone and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP). Primary treatment did not show any significant removal of DOAs while the removal efficiencies of total monitored DOAs by Membrane Bioreactor (MBR) and Bardenpho processes were found to be similar (~95% removal). The population was estimated using hydrochemical parameters and human urine biomarkers and showed good agreement with wastewater treatment plant's estimates. Weekday-weekend variation in the consumption of alcohol and methamphetamine was found to be significant, with a higher estimated consumption during the weekends. Monitored DOAs in influent were present at highest concentrations during summer (23 μg/L), at low concentrations during winter (17 μg/L), and at lowest concentrations during heavy rainfall event (11 μg/L), possibly due to dilution. The population normalised mass loads of DOAs were found to correlate with their metabolites, and morphine was found to correlate with nicotine metabolites.

Levels of 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) in raw wastewater as an innovative perspective for investigating population-wide exposure to third-hand smoke

Tobacco smoking is the major cause of many chronic diseases, especially lung cancer. Knowledge about population-wide tobacco use and exposure is essential to characterise its burden on public health and evaluate policy efficacy. Obtaining such knowledge remains challenging with current methods (e.g., surveys, biomonitoring) but can be achievable with wastewater analysis, a promising tool of retrieving epidemiology information. This study examined population-wide exposure to tobacco toxicants and carcinogens through wastewater analysis and explored relationships among these chemicals. Cotinine, trans-3'-hydroxycotinine, anabasine, anatabine and 4-(methylnitrosamino)-1-(3-pyridyl)-1-butanone (NNK) were analysed in samples from Greece, Switzerland and Belgium, where tobacco control policies are different. Measured per-capita mass loads were ranked as: nicotine biomarkers ≫ tobacco markers > carcinogens. Relationships between nicotine biomarkers and tobacco markers implied substantial use of non-tobacco nicotine items besides tobacco products. Geographic profiles of tobacco markers revealed higher levels in Geneva and Athens than Geraardsbergen and Ninove. Environmental third-hand smoke led to NNK detection, with elevated levels observed in Athens where indoor smoking is widespread, posing potential health risks to the population. Our novel outcomes are relevant for public health authorities as they provide indications about external exposure and can thus be used to plan and evaluate tobacco control policies.

Molecularly imprinted polymers for the detection of illegal drugs and additives: a review

This review (with 154 refs.) describes the current status of using molecularly imprinted polymers in the extraction and quantitation of illicit drugs and additives. The review starts with an introduction into some synthesis methods (lump MIPs, spherical MIPs, surface imprinting) of MIPs using illicit drugs and additives as templates. The next section covers applications, with subsections on the detection of illegal additives in food, of doping in sports, and of illicit addictive drugs. A particular focus is directed towards current limitations and challenges, on the optimization of methods for preparation of MIPs, their applicability to aqueous samples, the leakage of template molecules, and the identification of the best balance between adsorption capacity and selectivity factor. At last, the need for convincing characterization methods, the lack of uniform parameters for defining selectivity, and the merits and demerits of MIPs prepared using nanomaterials are addressed. Strategies are suggested to solve existing problems, and future developments are discussed with respect to a more widespread use in relevant fields. Graphical abstract This review gives a comprehensive overview of the advances made in molecularly imprinting of polymers for use in the extraction and quantitation of illicit drugs and additives. Methods for syntheses, highlighted applications, limitations and current challenges are specifically addressed.

Monitoring wastewater for assessing community health: Sewage Chemical-Information Mining (SCIM)

Timely assessment of the aggregate health of small-area human populations is essential for guiding the optimal investment of resources needed for preventing, avoiding, controlling, or mitigating human exposure risks, as well as for maintaining or promoting health. Seeking those interventions yielding the greatest benefit with respect to the allocation of resources is critical for making progress toward community sustainability, reducing health disparities, promoting social justice, and maintaining or improving collective health and well-being. More informative, faster, and less-costly approaches are needed for guiding investigation of cause-effect linkages involving communities and stressors originating from both the built and natural environments. One such emerging approach involves the continuous monitoring of sewage for chemicals that serve as indicators of the collective status of human health (or stress/disease) or any other facet relevant to gauging time-trends in community-wide health. This nascent approach can be referred to as Sewage Chemical-Information Mining (SCIM) and involves the monitoring of sewage for the information that resides in the form of natural and anthropogenic chemicals that enter sewers as a result of the everyday actions, activities, and behaviors of humans. Of particular interest is a specific embodiment of SCIM that would entail the targeted monitoring of a broad suite of endogenous biomarkers of key physiologic processes (as opposed to xenobiotics or their metabolites). This application is termed BioSCIM-an approach roughly analogous to a hypothetical community-wide collective clinical urinalysis, or to a hypothetical en masse human biomonitoring program. BioSCIM would be used for gauging the status or time-trends in community-wide health on a continuous basis. This paper presents an update on the progress made with the development of the BioSCIM concept in the period of time since its original publication in 2012, as well as the next steps required for its continued development.

Increased levels of the oxidative stress biomarker 8-iso-prostaglandin F2α in wastewater associated with tobacco use

Wastewater analysis has been demonstrated to be a complementary approach for assessing the overall patterns of drug use by a population while the full potential of wastewater-based epidemiology has yet to be explored. F₂-isoprostanes are a prototype wastewater biomarker to study the cumulative oxidative stress at a community level. In this work, 8-iso-prostaglandin F_2α (8-iso-PGF_2α) was analysed in raw 24 h-composite wastewater samples collected from 4 Norwegian and 7 other European cities in 2014 and 2015. Using the same samples, biomarkers of alcohol (ethyl sulfate) and tobacco (trans-3′-hydroxycotinine) use were also analysed to investigate any possible correlation between 8-iso-PGF_2α and the consumption of the two drugs. The estimated per capita daily loads of 8-iso-PGF_2α in the 11 cities ranged between 2.5 and 9.9 mg/day/1000 inhabitants with a population-weighted mean of 4.8 mg/day/1000 inhabitants. There were no temporal trends observed in the levels of 8-iso-PGF_2α, however, spatial differences were found at the inter-city level correlating to the degree of urbanisation. The 8-iso-PGF_2α mass load was found to be strongly associated with that of trans-3′-hydroxycotinine while it showed no correlation with ethyl sulfate. The present study shows the potential for 8-iso-PGF_2α as a wastewater biomarker for the assessment of community public health.

Refining correction factors for back-calculation of illicit drug use

The estimation of illicit drugs use through wastewater analysis has become an important issue in the last few years due to their large worldwide consumption, which results in economic, social and health costs. The amounts of urinary biomarkers of illicit drugs (selected drugs or their metabolites) measured in wastewater are used to back-calculate the consumption of a particular drug by the population and to monitor temporal and spatial trends of illicit drug use in a community. The reliability of back-calculation depends on different factors, one being the accuracy of correction factors. A wide range of correction factors have been used in different studies and some biases must be expected when comparing results. Most of the correction factors were developed several years ago, so they need to be updated to include the latest information on pharmacokinetics. Moreover, new comprehensive methods to treat data should be adopted. The goal of this study is to refine current correction factors for back-calculation of the most widely used illicit drugs: amphetamine, methamphetamine, 3,4-methylenedioxymethamphetamine (MDMA) and tetrahydrocannabinol (THC). The mean percentages of excretion of the parent drugs and their metabolites were calculated for each route of administration, utilizing all accessible pharmacokinetic studies in the literature. This allowed to select the most suitable drug target residue and a refined correction factor was obtained for each substance considering the most frequent route of administration. The refined correction factors we propose can be used in wastewater based epidemiology to standardize the back-calculation of these drugs. These results can be included in the best practice protocol currently adopted in EU studies in order to reduce uncertainty and improve the comparability of results.

Profiles and changes in stimulant use in Belgium in the period of 2011-2015

Adapting illicit drug policy strategies requires detailed knowledge on types and amounts of substances consumed by the target population. In this study, we applied wastewater-based epidemiology to detect spatio-temporal changes in the relative amounts of stimulants (amphetamine, methamphetamine, methylenedioxymethamphetamine (MDMA), cocaine) used in seven locations in Belgium over 2011-2015. Clear geographical differences were observed with stimulant users in large cities (Antwerp, Brussels) showing a preference for cocaine, while amphetamine use was most abundant in smaller cities (Geraardsbergen, Koksijde, Lier, Ninove, Ostend). Results obtained across õdifferent years revealed that the investigated substances had a stable share in the total amount of stimulants used, suggesting that habits of stimulant use remained constant, although differences in absolute amounts were observed across years. Investigation of the weekly pattern in stimulant use showed an increase in the use of MDMA on the weekends compared to cocaine and amphetamine.

Refining the excretion factors of methadone and codeine for wastewater analysis - Combining data from pharmacokinetic and wastewater studies

Analysing drug residues in wastewater (wastewater analysis) to monitor the consumption of those drugs in the population has become a complementary method to epidemiological surveys. In this method, the excretion factor of a drug (or the percentage of drug metabolites excreted through urine) is a critical parameter for the back-estimation of the consumption of a drug. However, this parameter is usually derived from a small database of human pharmacokinetic studies. This is true for methadone and codeine, the two most commonly used opioids and also common substances of abuse. Therefore, we aimed to refine the current excretion factors used for estimating methadone and codeine by analysing published data from the literature on the excretion of methadone, its main metabolite, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), and codeine. Our review included both human drug pharmacokinetic studies and wastewater analysis studies. We found that while the commonly used excretion factor of methadone (~27.5%) was relatively accurate, the excretion factor of EDDP, a better biomarker for methadone consumption in sewer epidemiology, should be twice that of methadone (i.e. 55%) instead of the current equal or half values. For codeine, the excretion factor should be ~30% instead of 63.5% or 10% as previously used in wastewater analysis studies. Data from wastewater analysis studies could be used in this way to refine the excretion factors of the drugs of interest.

Assessing geographical differences in illicit drug consumption--A comparison of results from epidemiological and wastewater data in Germany and Switzerland

BACKGROUND

Wastewater analysis is an innovative approach that allows monitoring illicit drug use at the community level. This study focused on investigating geographical differences in drug consumption by comparing epidemiological, crime and wastewater data.

METHODS

Wastewater samples were collected in 19 cities across Germany and Switzerland during one week, covering a population of approximately 8.1 million people. Self-report data and consumption offences for the investigated areas were used for comparison and to investigate differences between the indicators.

RESULTS

Good agreement between data sources was observed for cannabis and amphetamine-type stimulants, whereas substantial discrepancies were observed for cocaine. In Germany, an important distinction could be made between Berlin, Dortmund and Munich, where cocaine and particularly amphetamine were more prevalent, and Dresden, where methamphetamine consumption was clearly predominant. Cocaine consumption was relatively homogenous in the larger urban areas of Switzerland, although prevalence and offences data suggested a more heterogeneous picture. Conversely, marked regional differences in amphetamine and methamphetamine consumption could be highlighted.

CONCLUSIONS

Combining the available data allowed for a better understanding of the geographical differences regarding prevalence, typology and amounts of substances consumed. For cannabis and amphetamine-type stimulants, the complementarity of survey, police and wastewater data could be highlighted, although notable differences could be identified when considering more stigmatised drugs (i.e. cocaine and heroin). Understanding illicit drug consumption at the national scale remains a difficult task, yet this research illustrates the added value of combining complementary data sources to obtain a more comprehensive and accurate picture of the situation.

Data triangulation in the context of opioids monitoring via wastewater analyses

BACKGROUND

The need to contextualise wastewater-based figures about illicit drug consumption by comparing them with other indicators has been stressed by numerous studies. The objective of the present study was to further investigate the possibility of combining wastewater data to conventional statistics to assess the reliability of the former method and obtain a more balanced picture of illicit drug consumption in the investigated area.

METHODS

Wastewater samples were collected between October 2013 and July 2014 in the metropolitan area of Lausanne (226,000 inhabitants), Switzerland. Methadone, its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), the exclusive metabolite of heroin, 6-monoacetylmorphine (6-MAM), and morphine loads were used to estimate the amounts of methadone and heroin consumed.

RESULTS

Methadone consumption estimated from EDDP was in agreement with the expectations. Heroin estimates based on 6-MAM loads were inconsistent. Estimates obtained from morphine loads, combined to prescription/sales data, were in agreement with figures derived from syringe distribution data and general population surveys.

CONCLUSIONS

The results obtained for methadone allowed assessing the reliability of the selected sampling strategy, supporting its ability to capture the consumption of a small cohort (i.e., 743 patients). Using morphine as marker, in combination with prescription/sales data, estimates in accordance with other indicators about heroin use were obtained. Combining different sources of data allowed strengthening the results and suggested that the different indicators (i.e., administration route, average dosage and number of consumers) contribute to depict a realistic representation of the phenomenon in the investigated area. Heroin consumption was estimated to approximately 13 gd ay(-1) (118 g day(-1) at street level).

Systematic and day-to-day effects of chemical-derived population estimates on wastewater-based drug epidemiology

Population size is crucial when estimating population-normalized drug consumption (PNDC) from wastewater-based drug epidemiology (WBDE). Three conceptually different population estimates can be used: de jure (common census, residence), de facto (all persons within a sewer catchment), and chemical loads (contributors to the sampled wastewater). De facto and chemical loads will be the same where all households contribute to a central sewer system without wastewater loss. This study explored the feasibility of determining a de facto population and its effect on estimating PNDC in an urban community over an extended period. Drugs and other chemicals were analyzed in 311 daily composite wastewater samples. The daily estimated de facto population (using chemical loads) was on average 32% higher than the de jure population. Consequently, using the latter would systemically overestimate PNDC by 22%. However, the relative day-to-day pattern of drug consumption was similar regardless of the type of normalization as daily illicit drug loads appeared to vary substantially more than the population. Using chemical loads population, we objectively quantified the total methodological uncertainty of PNDC and reduced it by a factor of 2. Our study illustrated the potential benefits of using chemical loads population for obtaining more robust PNDC data in WBDE.