Wastewater-based epidemiology combined with local prescription analysis as a tool for temporalmonitoring of drugs trends - A UK perspective

Assessment of restriction measures implemented during COVID pandemics on community lifestyle choices via wastewater-based epidemiology

SARS-CoV-2 pandemic affected lifestyle habits, and the mental health and wellbeing of people around the world. In this manuscript, two towns (Paulton and Radstock) and two cities (Bath and Bristol) in Southwest England (> 1 million people) were monitored for two years using Wastewater-Based Epidemiology to assess impacts of COVID (including management measures such as lockdowns and movement restrictions) on community lifestyle choices: illicit drugs, legal stimulants, abused pharmaceuticals and pain pharma usage. Results were triangulated with key dates captured during the pandemic (national lockdowns, restrictions and social distancing measures, etc.). This highlighted a reduction in cocaine intake (as benzoylecgonine) (community average: -36 %) during the first lockdown and an increase in illicit drugs usage after the 3rd national lockdown (community averages for amphetamine: +8 %, cocaine/benzoylecgonine: +39 %, ketamine:+70 %) when restrictions were removed, and social interaction and recreational activities increased. There was a reduction in the intake of caffeine (as 1,7-dimethylxanthine) (community average:-39 %) after 3rd national lockdown coinciding with pubs reopening while nicotine intake (via cotinine) remained stable indicating lack of impact of COVID on smoking habits. Pain pharma often used in pain management resulting from injuries linked with sport activities (naproxen and diclofenac) showed decrease in usage due to lockdown restrictions in physical exercise and access to gyms/sport facilities.

Understanding treatment of pain during SARS-CoV-2 pandemic in a two-year intercity longitudinal study using wastewater-based epidemiology

SARS-CoV-2 pandemic had a significant impact on the society, economy, and health of people around the world with consequences that need to be better understood for future pandemic preparedness. This manuscript provides insights into the usage of pharmaceuticals for pain treatment management throughout SARS-CoV-2 pandemic. Four towns and cities with a total population of > 1 million people covering an area of 2000 km2 in South West England were monitored for twenty-four months. Results showed different patterns in pain pharma usage, with small towns having higher population normalised daily loads (PNDLs) than big cities for majority of pain killers studied. This is likely due to demographics of these cities with smaller cities having older population. Per capita consumption of non-steroidal anti-inflammatory drugs (NSAIDs) increased compared to pre-pandemic usage in line with SARS-CoV-2 infections (ibuprofen and acetaminophen), while body pain drugs (diclofenac and naproxen) decreased in line with restrictions and closure of sports facilities. Changes in population normalised daily intake (PNDI) of pain killers were particularly apparent during the 1st and 3rd national lockdown. Comparison of PNDIs with prescriptions highlighted differences related to medication availability (OTC drugs) and patients' nonadherence (prescribed drugs). In addition, several instances of direct disposal events across the catchments were observed which raises an issue of lack of pharma compliance and general understanding of potential environmental impacts from pharma usage.

Illicit Drugs in Surface Waters: How to Get Fish off the Addictive Hook

The United Nations World Drug Report published in 2022 alarmed that the global market of illicit drugs is steadily expanding in space and scale. Substances of abuse are usually perceived in the light of threats to human health and public security, while the environmental aspects of their use and subsequent emissions usually remain less explored. However, as with other human activities, drug production, trade, and consumption of drugs may leave their environmental mark. Therefore, this paper aims to review the occurrence of illicit drugs in surface waters and their bioaccumulation and toxicity in fish. Illicit drugs of different groups, i.e., psychostimulants (methamphetamines/amphetamines, cocaine, and its metabolite benzoylecgonine) and depressants (opioids: morphine, heroin, methadone, fentanyl), can reach the aquatic environment through wastewater discharge as they are often not entirely removed during wastewater treatment processes, resulting in their subsequent circulation in nanomolar concentrations, potentially affecting aquatic biota, including fish. Exposure to such xenobiotics can induce oxidative stress and dysfunction to mitochondrial and lysosomal function, distort locomotion activity by regulating the dopaminergic and glutamatergic systems, increase the predation risk, instigate neurological disorders, disbalance neurotransmission, and produce histopathological alterations in the brain and liver tissues, similar to those described in mammals. Hence, this drugs-related multidimensional harm to fish should be thoroughly investigated in line with environmental protection policies before it is too late. At the same time, selected fish species (e.g., Danio rerio, zebrafish) can be employed as models to study toxic and binge-like effects of psychoactive, illicit compounds.

Seasonal profile of common pharmaceuticals in edible bivalve molluscs

Pharmaceuticals are recognised as environmental contaminants of emerging concern (CECs) due to their increasing presence in the aquatic environment, along with high bioactivity linked to their therapeutic use. Therefore, information on environmental levels is urgently required. This study examined the presence of a range of common pharmaceuticals in oysters and mussels intended for human consumption from England and Wales using stable isotope dilution tandem mass spectrometry. A range of compounds were detected in bivalve tissue, with the Selective Serotonin Reuptake Inhibitor antidepressant sertraline being most abundant, reaching a maximum concentration of 22.1 ng/g wet weight shellfish tissue. Levels of all pharmaceuticals showed seasonal and geographical patterns. A dietary risk assessment revealed that the levels of pharmaceuticals identified in bivalve molluscs represent a clear hazard, but not a risk for the consumer. This study highlights the requirement for further monitoring of the presence of pharmaceuticals and other CECs in bivalve molluscs.

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.

Estimation of anti-diabetes drug metformin in Turkiye using wastewater-based epidemiology

Metformin is the most commonly used drug for the treatment of type 2 diabetes (T2D), which is dramatically increasing due to factors such as increasing obesity, physical inactivity, and aging of the population. Metformin analysis was carried out in composite wastewater samples seasonally collected from wastewater treatment plants in 10 cities in 2019 and 2020 30 cities in 2021 in Turkiye. Metformin was measured in all wastewater samples, with an average concentration of 97.81 μg/l in 2019, 75.19 μg/l in 2020, and 69.13 μg/l in 2021. This study was utilized to predict metformin usage in different sociodemographic regions in Turkiye using a wastewater-based epidemiology (WBE) approach. As a result of the analysis, the average metformin consumption in Turkiye was estimated to be 22.2 ± 9.6 [1.9-63.8] g/d/1,000 persons (mean ± SD [range]). Furthermore, these estimates were compared with data for time, sociodemographic characteristics, and patient numbers. Assessing the correlation with estimates and the socioeconomic classes of the cities in question revealed that cities with high-income levels had the lowest metformin use rate. Finally, the study provides supporting data aiding the development of public health strategies for decreasing the overall load of T2D across Turkiye.

A new Wastewater-Based Epidemiology workflow to estimate community wide non-communicable disease prevalence using pharmaceutical proxy data

This manuscript introduces a new wastewater-based epidemiology workflow for estimation of non-communicable diseases (NCDs) prevalence by using wastewater-based epidemiology (WBE) and pharmaceuticals/their metabolites as proxies for NCDs prevalence. 83 targets were selected (54 parent pharmaceuticals and 29 metabolites). Three critical aspects were tested: (i) Solid-Phase Extraction - Ultra-Performance Liquid Chromatography and Tandem Mass Spectrometry (SPE-UHPLC-MS/MS) method performance, (ii) biomarker stability under variable storage conditions (during sampling and long-term storage) and (iii) accounting for human metabolism in WBE back-calculations. High stability of most analytes was observed under tested storage conditions. A few exceptions include diazepam, dihydroketoprofen and 5-hydroxy-lansoprazole. Analyte recoveries varied between 75% and 125% for most analytes. MDLs ranged from 0.2 ng L-1 to 5.6 ng L-1, while MQLs from 0.2 ng L-1 to 16.8 ng L-1. The overall average method accuracy and precision were: 99.5% and 4.0% respectively. A fully validated method was tested using community wastewater in the Southwest of England to estimate pharmaceutical usage, test metabolism correction factors established and compare results with prescription data. The new WBE method for NCD approximation allowed for the estimation of the daily usage/intake of 69 NCD targets with a standardized approach and a consistent reporting format.

Retrospective spatiotemporal study of antidepressants in Slovenian wastewaters

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

Catchment area, fate, and environmental risks investigation of micropollutants in Danish wastewater

This study aimed to investigate the spatial distribution of micropollutants in wastewater related to catchment area, and their environmental risks and fate. About 24-h flow proportional effluent (n = 26) wastewater samples were collected from eight WWTPs across Denmark. From five of these WWTPs corresponding influent samples (n = 20) were collected. Samples were enriched by multi-layer solid phase and analysed by liquid chromatography-high-resolution mass spectrometry and comprehensive two-dimensional gas chromatography with high-resolution mass spectrometry detection. We detected and quantified 79 micropollutants from a list of 291 micropollutants in at least one influent or effluent wastewater sample. From this we found that 54 micropollutants decreased in concentrations during wastewater treatment, while O-desmethylvenlafaxine, carbamazepine, amitriptyline, benzothiazole, terbutryn, and citalopram increased in concentrations through the WWTP.The toxicity of effluent wastewater samples was assessed by EC50 using Raphidocelis subcapitata (R. subcapitata) and LC50 using the crustacean Daphnia magna (D. Magna), for which six micropollutants were detected above the predicted no-effect concentration. Our study demonstrates that catchment area influences the micropollutant composition of wastewater. Out of 19 pharmaceuticals, the measured concentration in influent wastewater was predicted within a factor of 10 from sale numbers and human excretion, which demonstrates the strong influence of catchment area on micropollutant composition.

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.

Continuous solar photo-Fenton for wastewater reclamation in operational environment at demonstration scale

For the first time, a continuous flow solar photo-Fenton demonstration plant has been assessed for wastewater reclamation according to the EU 2020/741 regulation. The treated water qualities achieved under two operating strategies (acidic and neutral pH) in a 100-m2 raceway pond reactor were explored in terms of liquid depth, iron source, reagent concentrations, and hydraulic residence time over three consecutive days of operation. The results obtained at acidic pH showed removal percentages of contaminants of emerging concern (CECs) > 75% and water quality classes B, C and D according to EU regulation at both assessed operating conditions, with treatment capacities up to 1.92 m3 m-2 d-1. At neutral pH with ferric nitrilotriacetate (Fe3+-NTA), 50% of CEC removal and only water quality class D were achieved with the most oxidizing condition assessed, giving a treatment capacity of 0.80 m3 m-2 d-1. The treatment capacities obtained in this work, which have never been achieved with solar water treatments, demonstrate the potential of this technology for commercial-scale application.

Legal Approaches to New Psychoactive Substances: First Empirical Findings

BACKGROUND

Generic drug legislation, i.e., simultaneously banning groups of drugs, has been introduced worldwide to counteract the trade and use of emerging "new psychoactive substances" (NPSs) more effectively.

SUMMARY

The potential and de facto positive and negative effects of generic drug legislation have been described using an analysis based on documented evaluations of the experiences in the UK and Germany, supplemented with data from other publicly available sources. In particular, the effects of generic drug legislation on availability, use, sales, and overall health harms of NPS, and switches from NPS to traditional (classical) drugs are addressed. The results show that the introduction of generic drug legislation in the UK and Germany has enabled stricter regulation of NPS but has also led to some major harms within the domain of public health. Depending on the population considered, the rate of NPS use remained stable, slightly declined, or increased following the banning of NPS. Once banned, NPSs were more often purchased on the black market, often together with other (more harmful) drugs. Moreover, NPS-related harms did not reduce following the ban, and in some cases even increased. Finally, when harmful NPS, like potent synthetic opioids and cannabinoids, become substantially used and endanger public health, legislators already have the legal means to ban the problem drug, thus overruling the need for a generic ban.

KEY MESSAGES

Generic drug legislation may facilitate drug law enforcement, but it is not (very) effective in counteracting NPS use and it may increase NPS-related public health problems. It is concluded that, overall, the advantages of generic drug legislation are overshadowed by its serious disadvantages.

Do the lockdown-imposed changes in a wastewater treatment plant catchment's socio-demographics impact longitudinal temporal trends in psychoactive pharmaceutical use?

Wastewater-based epidemiology (WBE) includes the analysis of human metabolic biomarkers of xenobiotics in influent wastewater. WBE complements existing drug utilization approaches and provides objective, spatio-temporal information on the consumption of pharmaceuticals in the general population. This approach was applied to 24-h composite influent wastewater samples from Leuven, Belgium. Daily samples were analysed from September 2019 to December 2019 (n = 76), and on three days of the week (Monday, Wednesday, Saturday) from January 2020 to April 2022 (n = 367). Sample analysis consisted of 96-well solid-phase extraction and liquid chromatography coupled to tandem mass spectrometry. Measured concentrations of 21 biomarkers for antidepressant and opioid use were converted to population-normalized mass loads (PNML) by considering the flow rate and catchment population. To capture population movements, mobile phone data was used. Amitriptyline, hydroxy-bupropion, norcitalopram, citalopram, normirtazapine, trazodone, O-desmethylvenlafaxine, codeine, 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP), methadone, morphine, O-desmethyltramadol, and tramadol were included in the temporal assessment since concentrations were above the lower limit of quantification. The PNML of most biomarkers increased (with 3-119 %) throughout the sampling period. The population disruption during the COVID-19 pandemic led to a major change in the socio-demographics of the catchment area, resulting in temporal differences in the PNML of the different biomarkers. As such, higher PNML were observed during the different lockdown phases, which were characterized by the outflow of university students and a decreasing commuting in and out the catchment area. The effects of the fluctuating socio-demographics of the catchment population were further evidenced by the different week-weekend pattern of PNMLs over the course of the sampling campaign. Mean parent/metabolite ratios (i.e., citalopram/norcitalopram, tramadol/O-desmethyltramadol, venlafaxine/O-desmethylvenlafaxine, and methadone/EDDP) remained relatively stable throughout the entire sampling campaign (RSD% below 25 % for all ratios, except for methadone/EDDP) and therefore were not affected by this population change.

20-Month monitoring of SARS-CoV-2 in wastewater of Curitiba, in Southern Brazil

The COVID-19 pandemic resulted in the collapse of healthcare systems and led to the development and application of several approaches of wastewater-based epidemiology to monitor infected populations. The main objective of this study was to carry out a SARS-CoV-2 wastewater based surveillance in Curitiba, Southern Brazil Sewage samples were collected weekly for 20 months at the entrance of five treatment plants representing the entire city and quantified by qPCR using the N1 marker. The viral loads were correlated with epidemiological data. The correlation by sampling points showed that the relationship between the viral loads and the number of reported cases was best described by a cross-correlation function, indicating a lag between 7 and 14 days amidst the variables, whereas the data for the entire city presented a higher correlation (0.84) with the number of positive tests at lag 0 (sampling day). The results also suggest that the Omicron VOC resulted in higher titers than the Delta VOC. Overall, our results showed that the approach used was robust as an early warning system, even with the use of different epidemiological indicators or changes in the virus variants in circulation. Therefore, it can contribute to public decision-makers and health interventions, especially in vulnerable and low-income regions with limited clinical testing capacity. Looking toward the future, this approach will contribute to a new look at environmental sanitation and should even induce an increase in sewage coverage rates in emerging countries.

High resolution mass spectrometry (HRMS) determination of drugs in wastewater and wastewater based epidemiology in Cadiz Bay (Spain)

Multi-residue methods for the determination of the myriad of compounds of emerging concern (CECs) entering in the environment are key elements for further assessment on their distribution and fate. Here, we have developed an analytical protocol for the simultaneous analysis of 195 prescription, over-the-counter, and illicit drugs by using a combination of solid phase extraction (SPE) and determination by liquid chromatography coupled to high resolution mass spectrometry (LC-HRMS). The method was applied to the analysis of influent sewage samples from 3 wastewater treatment plants (WWTPs) from Cadiz Bay (SW Spain), enabling the quantification of more than 100 pharmaceuticals, 19 of them at average concentrations higher than 1 μg L^-1, including caffeine (92 μg L^-1), paracetamol (72 μg L^-1), and ibuprofen (56 μg L^-1), as well as several illicit drugs (e.g., cocaine). Wastewater based epidemiology (WBE) was applied for 27 of the detected compounds to establish their consumption in the sampling area, which has been never attempted before. Caffeine, naproxen, and salicylic acid stood out because of their high consumption (638, 51, and 20 g d^-1·1000pop^-1, respectively). Regarding illicit drugs, cocaine showed the highest frequency of detection and we estimated an average consumption of 3683 mg d^-1·1000pop^-1 in Cadiz Bay. The combination of new HRMS methods, capable of discriminating thousands of chemicals, and WBE will allow for a more comprehensive characterization of chemical substances and their consumption in urban environments in the near future.

Trends and challenges in analytical chemistry for multi-analysis of illicit drugs employing wastewater-based epidemiology

Wastewater-based epidemiology (WBE) for quantification of illicit drug biomarkers (IDBs) in wastewater samples is an effective tool that can provide information about drug consumption. The most commonly quantified IDBs belong to different chemical classes, including cocaine, amphetamine-type stimulants, opioids, and cannabinoids, so the different chemical properties of these molecules pose a challenge in the development of analytical methods for multi-analyte analysis. Recent workflows include the steps of sampling and storage, sample preparation using solid-phase extraction (SPE) or without extraction, and quantification of analytes employing gas or liquid chromatography coupled with mass spectrometry. The greatest difficulty is due to the fact that wastewater samples are complex chemical mixtures containing analytes with different chemical properties, often present at low concentrations. Therefore, in the development of analytical methods, there is the need to simplify and optimize the analytical workflows, reducing associated uncertainties, analysis times, and costs. The present work provides a critical bibliographic survey of studies published from the year 2020 until now, highlighting the challenges and trends of published analytical workflows for the multi-analysis of IDBs in wastewater samples, considering sampling and sample preparation, method validation, and analytical techniques.

A year-long study of the occurrence and risk of over 140 contaminants of emerging concern in wastewater influent, effluent and receiving waters in the Republic of Ireland

Despite being a developed country in the European Union (EU), knowledge of the nature and extent of contamination of water bodies with contaminants of emerging concern (CECs) in Ireland is limited. In this study, >140 CECs including pharmaceuticals, pesticides and personal care products were monitored in monthly samples of wastewater treatment plant (WWTP) influent, effluent and receiving surface waters at both an urban and a rural location (72 samples in total) in Ireland over a 12-month period in 2018-2019. In total, 58 CECs were detected, including several EU Water Framework Directive Watch List compounds. Of all classes, the highest concentrations were measured for pharmaceuticals across all media, i.e., propranolol in surface waters (134 ng·L^-1), hydrochlorothiazide in effluent (1067 ng·L^-1) and venlafaxine in influent wastewater (8273 ng·L^-1). Overall, high wastewater treatment removal was observed and a further reduction in CEC occurrence and concentration was measured via dilution in the receiving river environment. Lastly, an environmental risk assessment (ERA) was performed using risk quotients (RQ), which revealed that in surface waters, total RQ for all CECs was an order of magnitude lower than in effluents. The majority of CECs in surface waters posed a lower risk except E2 and EE2 which presented a medium risk (RQs of 3.5 and 1.1, respectively) in the rural area. This work represents the most comprehensive CEC monitoring dataset to date for Ireland which allowed for an ERA prioritisation to be performed for the first time.

The burden of city's pain treatment - A longitudinal one year study of two cities via wastewater-based epidemiology

This paper explores Wastewater-Based Epidemiology (WBE) as a tool enabling understanding of city's pain treatment in an intercity longitudinal study. An intensive 13-month monitoring programme was undertaken in two adjacent urban areas in South-West England: a small commuter town Keynsham and the city of Bath (>180 samples collected). The study has shown a great potential of using triangulated WBE and National health Service (NHS) prescription data in understanding pain treatment in two contrasting communities with strong apparent seasonal patterns of short pain medications vs chronic pain treatment as well as the type of treatment used (e.g. oral vs topical). Community-wide usage of Non-Steroidal Anti-inflammatory Drugs (NSAIDs) and paracetamol in the intercity study is population size and season driven with the highest usage recorded in winter months. This contrasts with other pain pharmaceuticals, especially those used for chronic pain, where no/limited seasonal usage was recorded. Unmetabolized NSAIDs are, to a large extent, directly disposed of into the sewerage system bypassing metabolism due to their topical application. This is particularly apparent in winter months with naproxen showing the highest seasonal variability. Pharma/met (ratio of pharmaceutical and its metabolite concentration) analysis allows for tracking topical (non-metabolic) application/down-the-drain disposal of pharmaceuticals with frequent instances of direct disposal of NSAIDs into the sewerage system observed. Normalisation of pharma markers to population size shows comparable estimates of pharma usage in the two cities confirming population as the main driver of pharma loads in wastewater. Variable application patterns of pain pharmaceuticals make back-calculation of intake more convoluted. Intake calculated using percentage excretion of parent NSAIDs will likely lead to overestimation, as it is assumed that NSAIDs are subject to extensive metabolism (this is not the case for topical applications). Intake calculated using percentage excretion of metabolites (or parent compound) as consumption markers leads to underestimation of NSAIDs usage due to contributions from topical application not being accounted for. Prescription data indicates cumulative internal and topical usage, but the data ignores large proportion of over-the-counter usage. Therefore, we have proposed a combined approach allowing for estimation of total usage including, and differentiating between, topical application and oral administration.

Consumption of common illicit drugs in twenty-one cities in southwest China through wastewater analysis

Wastewater-based epidemiology (WBE) was applied to estimate illicit drugs consumption at a provincial scale in southwest China. A large-scale wastewater sampling campaign was carried out from October to November in 2021 in 156 different wastewater treatment plants (WWTPs). Two 24-h composite influent wastewater samples were collected in each WWTP. Concentrations of 11 illicit drugs or their metabolites were determined using liquid chromatography coupled with tandem mass spectrometry (LC-MS/MS). Benzoylecgonine, cocaine, 6-monoacetylmorphine, norketamine, 3,4-methylenedioxymethamphetamine (MDMA), and MDA were not detected in any of the wastewater samples. Methamphetamine and morphine were detected in >84% of samples, while ketamine was found in about 6% of the samples. The city-specific population-weighted consumption of methamphetamine and ketamine were in the range of 0.6-49.7 and N.D.-7.0 mg 1000 inh^-1 day^-1, respectively, with provincial population-weighted values of 22.6 and 2.4 mg 1000 inh^-1 day^-1 in southwest China. The city-specific load of morphine varied from 3.2 to 10.2 mg 1000 inh^-1 day^-1, with provincial population-weighted load of 6.7 mg 1000 inh^-1 day^-1. Taking into account therapeutic use of morphine and codeine, the provincial heroin consumption was estimated to be 10.3 mg 1000 inh^-1 day^-1, ranging from 1.7 to 18.5 mg 1000 inh^-1 day^-1 in 21 cities. Overall, the patterns of illicit drugs use were similar across southwest China, with high prevalence of methamphetamine and heroin, but relatively low use of ketamine. These findings could provide accurate drugs consumption information for timely identifying potential hotspots of illicit drugs use in southwest China.

Research needs for optimising wastewater-based epidemiology monitoring for public health protection

Wastewater-based epidemiology (WBE) is an unobtrusive method used to observe patterns in illicit drug use, poliovirus, and severe acute respiratory syndrome coronavirus-2 (SARS-CoV-2). The pandemic and need for surveillance measures have led to the rapid acceleration of WBE research and development globally. With the infrastructure available to monitor SARS-CoV-2 from wastewater in 58 countries globally, there is potential to expand targets and applications for public health protection, such as other viral pathogens, antimicrobial resistance (AMR), pharmaceutical consumption, or exposure to chemical pollutants. Some applications have been explored in academic research but are not used to inform public health decision-making. We reflect on the current knowledge of WBE for these applications and identify barriers and opportunities for expanding beyond SARS-CoV-2. This paper critically reviews the applications of WBE for public health and identifies the important research gaps for WBE to be a useful tool in public health. It considers possible uses for pathogenic viruses, AMR, and chemicals. It summarises the current evidence on the following: (1) the presence of markers in stool and urine; (2) environmental factors influencing persistence of markers in wastewater; (3) methods for sample collection and storage; (4) prospective methods for detection and quantification; (5) reducing uncertainties; and (6) further considerations for public health use.

Occurrence and Transformation of Ephedrine/Pseudoephedrine and Methcathinone in Wastewater in China

Previous wastewater-based epidemiology studies on methcathinone (MC), a controlled substance in many countries, attributed its occurrence in wastewater to its misuse. However, such attribution did not consider the possibility that MC may also come from the transformation of ephedrine (EPH) and pseudo-ephedrine (PEPH). In this work, EPH/PEPH and MC in wastewater of six major Chinese cities were systematically examined. EPH/PEPH concentrations in all the cities showed clear seasonal variations, with maximum and minimum concentrations observed in winter and summer, respectively. In contrast, MC concentrations were the lowest in winter, leading to minimum concentration ratios between MC and EPH/PEPH in winter. Lack of MC seizure in the cities suggests that MC abuse could not account for the ubiquitous detection of the substance in the wastewater of these cities. Batch experiments confirmed EPH/PEPH transformation into MC in wastewater. The significantly lower transformation rate at a lower temperature was consistent with low MC concentrations in winter. These results indicate that when monitoring MC through wastewater, EPH/PEPH concentrations must be determined simultaneously to avoid false identification of MC abuse. The observed ratios of MC to EPH/PEPH concentrations in this work may be used to determine MC abuse. Alternatively, other biomarkers (e.g., cathinone) may be considered to avoid interference from EPH/PEPH transformation.

Contribution of Illicit Drug Use to Pharmaceutical Load in the Environment: A Focus on Sub-Saharan Africa

Illicit drug abuse and addiction are universal issues requiring international cooperation and interdisciplinary and multisectoral solutions. These addictive substances are utilized for recreational purposes worldwide, including in sub-Saharan Africa. On the other hand, conventional wastewater treatment facilities such as waste stabilization ponds lack the design to remove the most recent classes of pollutants such as illicit drug abuse. As a result, effluents from these treatment schemes contaminate the entire ecosystem. Public health officials are concerned about detecting these pollutants at alarming levels in some countries, with potential undesirable effects on aquatic species and increased health hazards through exposure to contaminated waters or recycling treated or untreated effluents in agriculture. Contaminants including illicit substances enter the environment by human excreta following illegal intake, spills, or through direct dumping, such as from clandestine laboratories, when their manufacturer does not follow accepted production processes. These substances, like other pharmaceuticals, have biological activity and range from pseudopersistent to highly persistent compounds; hence, they persist in the environment while causing harm to the ecosystem. The presence of powerful pharmacological agents such as cocaine, morphine, and amphetamine in water as complex combinations can impair aquatic organisms and human health. These compounds can harm human beings and ecosystem health apart from their low environmental levels. Therefore, this article examines the presence and levels of illicit substances in ecological compartments such as wastewater, surface and ground waters in sub-Saharan Africa, and their latent impact on the ecosystem. The information on the occurrences of illicit drugs and their metabolic products in the sub-Saharan Africa environment and their contribution to pharmaceutical load is missing. In this case, it is important to research further the presence, levels, distribution, and environmental risks of exposure to human beings and the entire ecosystem.

Human population as a key driver of biochemical burden in an inter-city system: Implications for One Health concept

This paper tests the hypothesis that human population and city function are key drivers of biochemical burden in an inter-city system, which can be used to inform One Health actions as it enables a holistic understanding of city's metabolism encompassing all of the activities of a city in a single model: from lifestyle choices, through to health status and exposure to harmful chemicals as well as effectiveness of implemented management strategies. Chemical mining of wastewater for biophysico-chemical indicators (BCIs) was undertaken to understand speciation of BCIs in the context of geographical as well as community-wide socioeconomic factors. Spatiotemporal variabilities in chemical and biological target groups in the studied inter-city system were observed. A linear relationship (R² > 0.99) and a strong positive correlation between most BCIs and population size (r > 0.998, p < 0.001) were observed which provides a strong evidence for the population size as a driver of BCI burden. BCI groups that are strongly correlated with population size and are intrinsic to humans' function include mostly high usage pharmaceuticals that are linked with long term non-communicable conditions (NSAIDs, analgesics, cardiovascular, mental health and antiepileptics) and lifestyle chemicals. These BCIs can be used as population size markers. BCIs groups that are produced as a result of a specific city's function (e.g. industry presence and occupational exposure or agriculture) and as such are not correlated with population size include: pesticides, PCPs and industrial chemicals. These BCIs can be used to assess city's function, such as occupational exposure, environmental or food exposure, and as a proxy of community-wide health. This study confirmed a strong positive correlation between antibiotics (ABs), population size and antibiotic resistance genes (ARGs). This confirms the population size and AB usage as the main driver of AB and ARG levels and provides an opportunity for interventions aimed at the reduction of AB usage to reduce AMR. Holistic evaluation of biophysicochemical fingerprints (BCI burden) of the environment and data triangulation with socioeconomic fingerprints (indices) of tested communities are required to fully embrace One Health concept.

PrAna: an R package to calculate and visualize England NHS primary care prescribing data

Background

The objective of this work to calculate prescribed quantity of an active pharmaceutical ingredient (API) in prescription medications for human use, to facilitate research on the prediction of amount of API released to the environment and create an open-data tool to facilitate spatiotemporal and long-term prescription trends for wider usage.

Design

We have developed an R package, PrAna to calculate the prescribed quantity (in kg) of an APIs by postcode using England’s national level prescription data provided by National Health Service, for the years 2015–2018. Datasets generated using PrAna can be visualized in a real-time interactive web-based tool, PrAnaViz to explore spatiotemporal and long-term trends. The visualisations can be customised by selecting month, year, API, and region.

Results

PrAnaViz’s targeted API approach is demonstrated with the visualisation of prescribed quantities of 14 APIs in the Bath and North East Somerset (BANES) region during 2018. Once the APIs list is loaded, the back end retrieves relevant data and populates the graphs based on user-defined data features in real-time. These plots include the prescribed quantity of APIs over a year, by month, and individual API by month, general practice, postcode, and medicinal form. The non-targeted API approach is demonstrated with the visualisation of clarithromycin prescribed quantities at different postcodes in the BANES region.

Conclusion

PrAna and PrAnaViz enables the analysis of spatio-temporal and long-term trends with prescribed quantities of different APIs by postcode. This can be used as a support tool for policymakers, academics and researchers in public healthcare, and environmental scientist to monitor different group of pharmaceuticals emitted to the environment and for prospective risk assessment of pharmaceuticals in the environment.

Assessment of a wide array of organic micropollutants of emerging concern in wastewater treatment plants in Greece: Occurrence, removals, mass loading and potential risks

Exploring the contamination profile of multi-class emerging contaminants (ECs) in wastewater is highly desirable. To this end, the occurrence, removal, mass loading and risks associated with a large panel of pharmaceuticals and personal care products, illicit drugs, perfluorinated compounds and organophosphate flame retardants in two wastewater treatment plants (WWTPs) in the region of Thessaloniki (Greece) after a survey is illustrated. Influent and effluent wastewaters were submitted to solid phase extraction on Oasis HLB cartridges, followed by ultra-high-performance liquid chromatography Orbitrap high-resolution mass spectrometry (UHPLC-Orbitrap MS). Influent concentrations in both WWTPs were notably higher than effluent, with caffeine, acetaminophen, irbesartan and valsartan being the most ubiquitous compounds, exhibiting elevated concentrations. Average effluent concentrations ranged from below the method quantification limits (<MQL) to remarkably high values (μg L^-1 scale), such as for caffeine, acetaminophen, diclofenac, irbesartan and valsartan, among others. Removal efficiencies ranged between -273% for lamotrigine and 100%, i.e., for the UV filter BP1. Notably, the polar compounds such as cytarabine, methotrexate and capecitabine were removed at a rate >80% in both WWTPs, allowing the correlation between logK_ow and removals. Interesting trends for the illicit drugs were revealed by means of mass loading estimation, as in the case of benzoylecgonine (71.6 mg/day/1000 inhabitants). Ecotoxicological risk assessment was evaluated for both single components and mixture, using three approaches: risk quotient (RQ), risk quotient considering frequency (RQ_f) and toxic units (TU). Irbesartan and telmisartan posed a high risk in all trophic levels, while fish was the most sensitive taxa for diclofenac. This work aspires to intensify the surveillance programs for the receiving water bodies, as well as to motivate the investigation of toxicity to non-target organisms.

A two-year study of emerging micro-pollutants and drugs of abuse in two Western Cape wastewater treatment works (South Africa)

This study evaluated the occurrence and fate of fourteen contaminants of emerging concern (CECs) at two South African wastewater treatment works (WWTW). Daily loads of the drug targets were calculated in the aqueous phase of influent- and effluent wastewater to evaluate their fate at the treatment works, along with population-normalised daily loads in raw influent wastewater to identify community-wide substance use patterns in the two study areas. Environmental risk characterisation of the CECs at WWTW effluent discharge was done using conventional risk quotient (RQ) estimations. A significant reduction of most CECs was observed at both WWTW locations, except for some that have been previously recorded to persist through various WWTW processes globally, including the illicit drug methaqualone that was reported here for the first time to evaluate its fate during wastewater treatment, substance use trends, and potential toxicological risk. Moderate-to high-RQs were estimated for several target CECs during the sampling period for both treatment facilities. The results presented here suggest the need for a multi-disciplinary approach to WWTW monitoring of CECs and highlight the need for further refinement of risk assessment approaches to mitigate recalcitrant- or pseudo-persistent CECs in wastewater discharge. Such refinement should include: (1) identifying the potential ecological risk on a wider range of sentinel indicators, (2) interaction of CECs with various biochemical pathways (including sub-lethal toxicity responses), (3) identifying the persistence and toxicological risks of breakdown products and (4) partitioning of CECs in the aqueous environment and/or bioaccumulation in freshwater biota.

Monitoring geographical differences in illicit drugs, alcohol, and tobacco consumption via wastewater-based epidemiology: Six major cities in Turkey

A national wastewater-based epidemiology (WBE) monitoring campaign has been initiated to determine the trends in drug consumption in Turkey since 2019. This study aimed to present the wastewater monitoring results for four periods in 2019 for six major cities with 17 wastewater treatment plants. The study investigated heroin (HER), amphetamine (AMP), methamphetamine (METH), cocaine (COC), 3,4-methylenedioxymethamphetamine (MDMA), cannabis, alcohol, and tobacco to understand the temporal and geographical drug consumption trends. The results indicated a trend of regular cannabis use in all the cities. Considering geographical variations, the drug usage trends were not homogeneous within the country for any of the investigated drugs, except cannabis. HER consumption was predominant in Denizli (1042.48 mg/1000 inh/day), while İzmir and Antalya (154.10 and 79.56 mg/1000 inh/day, respectively) topped for COC consumption. Aydın had the highest consumption levels of AMP (90.03 mg/1000 inh/day) and METH (358.13 mg/1000 inh/day), while MDMA consumption was the highest in Samsun (157.64 mg/1000 inh/day). Tobacco consumption was high in Aydın (8791.69 mg/1000 inh/day) and Antalya (5375.17 mg/1000 inh/day), whereas alcohol consumption was higher in Bursa than in the other cities (53434.61 mL/1000 inh/day). There were no statistically significant differences in the weekend consumption levels of the investigated drugs among these six cities. Although this study included the results of 1 year of consumption monitoring, the data confirms internationally published information on the drug trafficking routes of conventional drugs in this region, especially the Heroin-Balkan route. Results from further sampling will enable accurate evaluation of global drug consumption and trafficking, in addition to alcohol and tobacco use.

Deaths from novel psychoactive substances in England, Wales and Northern Ireland: Evaluating the impact of the UK psychoactive substances act 2016

BACKGROUND

'Legal highs' began appearing in the UK in the mid-2000s. Whilst many of these substances were controlled under the 1971 Misuse of Drugs Act, novel compounds and new variants of controlled compounds were continuously being introduced to the recreational drug market. The Psychoactive Substances Act (PSA) was therefore implemented in 2016 as a blanket ban on all novel psychoactive substances (NPS).

AIM

To evaluate the impact of the PSA on deaths following NPS use in England, Wales and Northern Ireland.

METHODS

Cases reported to the National Programme on Substance Abuse Deaths where death had occurred 3 years pre- or post-implementation of the PSA were extracted. Cases with NPS detected at post-mortem were analysed and compared against cases non-NPS cases.

RESULTS

293 deaths with NPS detected were identified; 91 occurring before the PSA and 202 afterwards, indicating an 222.0% post-PSA increase. Contrastingly, non-NPS drug-related death case reporting increased by only 8.0%. Synthetic cannabinoid, anxiolytic/sedative and stimulant NPS were detected in the largest proportions of deaths pre-PSA; post-PSA stimulant NPS detections reduced whilst synthetic cannabinoid and anxiolytic/sedative detections increased.Post-PSA, average decedent age increased significantly (mean age pre-PSA 34.4 ± 10.8 vs post-PSA 38.3 ± 9.4), and they were significantly more likely to have been living in deprived areas (pre-PSA 50.0% vs post-PSA 65.9%).

CONCLUSIONS

Reporting of deaths following NPS use has risen despite introduction of the PSA. Whilst deaths amongst younger individuals and those living in more affluent areas has reduced, additional approaches to prohibition are needed to curb their persistence in deprived demographics.

Current and future perspectives for wastewater-based epidemiology as a monitoring tool for pharmaceutical use

The medical and societal consequences of the misuse of pharmaceuticals clearly justify the need for comprehensive drug utilization research (DUR). Wastewater-based epidemiology (WBE) employs the analysis of human metabolic excretion products in wastewater to monitor consumption patterns of xenobiotics at the population level. Recently, WBE has demonstrated its potential to evaluate lifestyle factors such as illicit drug, alcohol and tobacco consumption at the population level, in near real-time and with high spatial and temporal resolution. Up until now there have been fewer WBE studies investigating health biomarkers such as pharmaceuticals. WBE publications monitoring the consumption of pharmaceuticals were systematically reviewed from three databases (PubMed, Web of Science and Google Scholar). 64 publications that reported population-normalised mass loads or defined daily doses of pharmaceuticals were selected. We document that WBE could be employed as a complementary information source for DUR. Interest in using WBE approaches for monitoring pharmaceutical use is growing but more foundation research (e.g. compound-specific uncertainties) is required to link WBE data to routine pharmacoepidemiologic information sources and workflows. WBE offers the possibility of i) estimating consumption of pharmaceuticals through the analysis of human metabolic excretion products in wastewater; ii) monitoring spatial and temporal consumption patterns of pharmaceuticals continuously and in near real-time; and iii) triangulating data with other DUR information sources to assess the impacts of strategies or interventions to reduce inappropriate use of pharmaceuticals.

Multiresidue antibiotic-metabolite quantification method using ultra-performance liquid chromatography coupled with tandem mass spectrometry for environmental and public exposure estimation

This manuscript describes a new multiresidue method utilising ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS) via multiple reaction monitoring (MRM), for the identification and quantification of 58 antibiotics and their 26 metabolites, in various solid and liquid environmental matrices. The method was designed with a ‘one health’ approach in mind requiring multidisciplinary and multisectoral collaborative efforts. It enables comprehensive evaluation of antibiotic usage in surveyed communities via wastewater-based epidemiology, as well as allowing for the assessment of potential environmental impacts. The instrumental performance was very good, demonstrating linearity up to 3000 μg L⁻¹, and high accuracy and precision. The method accuracy in several compounds was significantly improved by dividing calibration curves into separate ranges. This was accompanied by applying a weighting factor (1/x). Microwave-assisted and/or solid-phase extraction of analytes from liquid and solid matrices provided good recoveries for most compounds, with only a few analytes underperforming. Method quantification limits were determined as low as 0.017 ng L⁻¹ in river water, 0.044 ng L⁻¹ in wastewater, 0.008 ng g⁻¹ in river sediment, and 0.009 ng g⁻¹ in suspended solids. Overall, the method was successfully validated for the quantification of 64 analytes extracted from aqueous samples, and 45 from solids. The analytes that underperformed are considered on a semi-quantitative basis, including aminoglycosides and carbapenems. The method was applied to both solid and liquid environmental matrices, whereby several antibiotics and their metabolites were quantified. The most notable antibiotic-metabolite pairs are three sulfonamides and their N-acetyl metabolites; four macrolides/lincomycins and their N-desmethyl metabolites; and five quinolone metabolites.

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.

Showcasing the potential of wastewater-based epidemiology to track pharmaceuticals consumption in cities: Comparison against prescription data collected at fine spatial resolution

While the extent of pharmaceutical consumption within a society/community is of high relevance to its health, economy and general wellbeing, this data is often not readily available. Herein, we strengthen a wastewater-based epidemiology (WBE) approach as a way to track the consumption of pharmaceuticals within the sampled community. This method is less laborious than established questionnaire or databases approaches and allows a higher temporal and spatial resolution. The WBE approach was conducted by sampling influent wastewater from two wastewater treatment plants of different size. A total of 39 targeted compounds were quantified by liquid chromatography coupled with tandem mass spectrometry. The number of prescriptions and the defined daily doses for each prescription was obtained from the reference database of The Catalan Health System to validate the wastewater-based approach. The wastewater sampling and the data inquiry were both executed during the same period (October 2019) and standardised for comparison to treatments per 1,000 inhabitants per day. The back-calculation parameters were improved from previous studies by including the faecal excretion rate of the pharmaceuticals. For prescription only pharmaceuticals, where prescription numbers are expected to be a good estimate of consumption, our WBE approach agreed with 27 out of 32 (<0.7 order of magnitude). Common over-the-counter pharmaceuticals such as acetaminophen, ibuprofen and naproxen showed much higher values for treatments per day per 1,000 inhabitant in wastewater than prescribed, reflecting the usefulness of WBE in obtaining an estimate of the total consumption i.e. with and without a prescription.

New psychoactive substances in several European populations assessed by wastewater-based epidemiology

Wastewater-based epidemiology (WBE) can be a useful tool to face some of the existing challenges in monitoring the use of new psychoactive substances (NPS), as it can provide objective and updated information. This Europe-wide study aimed to verify the suitability of WBE for investigating the use of NPS. Selected NPS were monitored in urban wastewater by high performance liquid chromatography tandem mass spectrometry (HPLC-MS/MS). The main classical illicit drugs were monitored in the same samples to compare their levels with those of NPS. Raw composite wastewater samples were collected in 2016 and 2017 in 14 European countries (22 cities) following best practice sampling protocols. Methcathinone was most frequent (>65% of the cities), followed by mephedrone (>25% of the cities), and only mephedrone, methcathinone and methylone were found in both years. This study depicts the use of NPS in Europe, confirming that it is much lower than the use of classical drugs. WBE proved able to assess the qualitative and quantitative spatial and temporal profiles of NPS use. The results show the changeable nature of the NPS market and the importance of large WBE monitoring campaigns for selected priority NPS. WBE is valuable for complementing epidemiological studies to follow rapidly changing profiles of use of drugs.

Tracing consumption patterns of stimulants, opioids, and ketamine in China by wastewater-based epidemiology

Illicit drug use has long been a key issue of international concern, and the true situation is unknown to the relevant authorities. To develop a profile of comprehensive consumption patterns of illicit drugs in China, data from 34 wastewater treatment plants in 25 cities were collected to analyze four classes of drugs, including amphetamine-type stimulants, opioids, ketamine, and cocaine. They were identified and quantified in samples using methods based on gas chromatography coupled to mass spectrometry. According to the wastewater-based epidemiology (WBE) approach, an analysis of the consumption pattern was performed regarding per inhabitant consumption based on the revised metabolic rate. The consumption quantity of illicit drug and precursor was divided into four categories based on statistical difference analyses: methamphetamine and ephedrine (precursor) were the predominant drugs in the first category, followed by ketamine and heroin in the second category, methcathinone and 3,4-methylenedioxymethamphetamine (MDMA) in the third category, and cocaine and methadone in the fourth category. There were distinctive spatial patterns: heroin and cocaine consumption was higher in Southern China than in Northern China, heroin consumption was higher in Western China than in Eastern China, and the consumption of each drug differed across seven regions of China, especially with ephedrine and methcathinone consumption higher in North China; heroin consumption higher in Southwest, Central, and Northwest China; and ketamine and MDMA consumption higher in East, South, and Central China. Compared with findings in previous studies, there were temporal patterns, in which ketamine consumption presented a downward trend but heroin remained stable. Based on correlation analyses, there were the polydrug abuse patterns between heroin and cocaine, methcathinone and ketamine, and cocaine and MDMA. In general, this study based on WBE provides a comprehensive evaluation of drug consumption in China.

Quantifying nicotine and alcohol consumption in New Zealand using wastewater-based epidemiology timed to coincide with census

INTRODUCTION

Accurate and timely information about nicotine and alcohol consumption is needed to inform effective policy. Wastewater-based epidemiology provides an opportunity to quantify consumption, which can complement traditional data collection methods.

METHODS

Wastewater samples were collected from seven wastewater treatment plants on seven consecutive days in three regions of New Zealand during the same week as the national census (6 March 2018). Samples were analysed for nicotine and alcohol metabolites using liquid chromatography-tandem mass spectrometry. Detailed catchment maps were developed and per capita consumption calculated.

RESULTS

Observed nicotine consumption (mean 1528 ± 412 cigarettes/day/1000 people) was similar to national sales data. Observed alcohol consumption (mean 1155 ± 764 standard drinks/day/1000 people) was lower than estimated using alcohol availability data. Consumption of nicotine and alcohol was generally higher in the Bay of Plenty and Canterbury compared to Auckland, mirroring trends in the New Zealand Health Survey. Intra-regional differences were observed and the patterns could not be attributed to urbanisation alone. Nicotine consumption was consistent throughout the week whereas alcohol consumption often peaked at the weekend. Nicotine consumption was correlated with neighbourhood-deprivation. There was little correlation for alcohol.

DISCUSSION AND CONCLUSIONS

Wastewater-based epidemiology provides a quantitative dataset that complements traditional methods of investigating nicotine and alcohol consumption. Timing data collection to coincide with the census helps to account for the influence of population mobility when normalising consumption.

Effect of lockdown on wastewater characteristics: a comparison of two large urban areas

The effect of the lockdown imposed to limit the spread of SARS-CoV-2 in France between March 14 and May 11, 2020 on the wastewater characteristics of two large urban areas (with between 250,000 and 300,000 inhabitants) was studied. The number of outward and inward daily commuters was extracted from national census databases related to the population and their commuting habits. For urban area A, with the larger number of daily inward commuters (110,000, compared to 53,000 for B), lockdown was observed to have an effect on the monthly load averages of chemical oxygen demand, biochemical oxygen demand, total Kjeldahl nitrogen, total suspended solids and total phosphorus, all of which decreased (confidence level of 95%). This decrease, which varied between 20% and 40% and reached 45% for COD, can be related to the cessation of catering and activities such as hairdressing, which generate large amounts of graywater. The ammonium loads, due to the use of toilets before leaving for work and after returning from work, remained constant. In the case of urban area B, lockdown had no noticeable effect. More data would be necessary in the long term to analyze the effect of changes in the balance between ammonia and carbon sources on the operation of wastewater treatment plants.