Illicit drug consumption estimated using wastewater analysis and compared by settlement size in New Zealand

Bridging the gap between research and decision making: A European survey to enhance cooperation in wastewater-based epidemiology (WBE) for illicit drugs

OBJECTIVES

Illicit drug use presents a significant challenge to global health and public safety, requiring innovative and effective monitoring strategies. This study aimed to evaluate the current landscape of wastewater-based epidemiology (WBE) for monitoring illicit drugs in Europe, focusing on collaboration, current practices, and barriers, while identifying opportunities for improvement.

STUDY DESIGN

Cross-sectional survey-based study.

METHODS

Coordinated by the Sewage Analysis CORe Group Europe (SCORE) and the European Union Drugs Agency (EUDA), two surveys were conducted in 2023 targeting researchers and stakeholders using WBE for illicit drugs. Data were analysed to identify trends, gaps, and opportunities for improving WBE implementation.

RESULTS

The findings indicate a robust research infrastructure and diverse analytical methods among European institutions. Two-thirds of the participating countries reported using WBE data to inform policy. However, challenges persist, particularly in securing funding and coordination, as well as generating national estimates from multiple locations and addressing specific local policy needs.

CONCLUSIONS

WBE has proven to be a valuable tool for monitoring illicit drug trends and informing drug policies. To unlock its full potential, sustained funding, methodological standardization, and enhanced cooperation are essential. This study provides critical insights into the European WBE landscape, offering a roadmap for strengthening the integration of actionable WBE data into public health and policy frameworks.

Electrochemical Aptamer-Based Biosensors for Cocaine Detection in Human Saliva: Exploring Matrix Interference

Electrochemical aptamer-based biosensors (E-aptasensors) are emerging platforms for point-of-care (POC) detection of complex biofluids. Human saliva particularly offers a noninvasive matrix and unprecedented convenience for detecting illicit drugs, such as cocaine. However, the sensitivity of cocaine E-aptasensors is significantly compromised in saliva. Herein, we investigated the influence of salivary components on the sensing performance of a methylene blue (MB)-labeled classic cocaine aptamer by square-wave voltammetry (SWV), and in parallel, we report the development and optimization of a disposable E-aptasensor for cocaine detection fabricated by laser ablation. Cyclic voltammetry (CV), scanning electron microscopy (SEM), and atomic force microscopy (AFM) were used to study the cleanliness and surface topography of the disposable electrode surface. To enhance the sensing performance of the disposable platform, we developed a co-immobilization strategy by introducing both the target and 6-mercapto-1-hexanol (MCH) into the aptamer immobilization solution, achieving optimal sensing performance at the aptamer-to-MCH ratio of 1:100. In a buffer solution, we revealed that the aptasensor performs best at low ionic strength, the absence of multivalent ions, and neutral pH conditions, while salivary components such as viscosity and mucin have minimal impact. However, upon transition to human saliva, the presence of salivary proteins exerted a profound effect on the sensing performance. To reduce this impact, we discovered that a high NaCl concentration could significantly enhance the sensing response in saliva. This approach circumvents centrifugation and extensive dilution and facilitates cocaine detection in human saliva through a straightforward "mix-and-detect" method. This disposable aptasensor achieved a limit of detection (LOD) of 3.7 μM in 90% saliva, demonstrating immense promise for the application of electrochemical aptasensors in detecting cocaine, especially when administered via smoking.

Mapping consumptions and market size of cocaine, amphetamine and MDMA through wastewater analysis: A Dutch case study

BACKGROUND AND AIMS

Illicit drug consumption is associated with public health effects and criminal activities. This study aimed to estimate Illicit drug consumption and annual market in the Netherlands from wastewater analysis of drug residues.

METHODS

Residues of cocaine, amphetamine and 3,4-methylene dioxymethamphetamine (MDMA) were measured between 2015 and 2022 in 30 Dutch wastewater treatment plants serving both rural and urban populations. These wastewater treatment plants covered 20% of the total Dutch population. The Dutch annual retail market was estimated by extrapolating consumption to the total Dutch population, back-calculating consumption volume, correcting for drug purity and street price collected in voluntary checking services, and accounting for the correlation of consumption and urbanity.

RESULTS

The per capita MDMA and cocaine consumption correlated positively with the urbanity of the wastewater treatment plant catchments with r2 of 31% and 64%, respectively. Amphetamine did not show a significant correlation with urbanity. The three studied drugs were conservatively estimated to cover an average annual market value of 903 (95% prediction interval 829 to 987) million Euro for the studied period. Market estimations from prevalence figures and interceptions of international trade were similar.

CONCLUSIONS

Illicit drug consumption in the Netherlands appears to correlate positively with urban (in contrast to rural) areas. Wastewater analysis can be used to estimate the volume and monetary value of illicit drug markets as a proof of concept.

Monitoring the dynamics of ketamine analogues use in China through wastewater analysis: The emergence of 2-FDCNEK and 2-MDCK

Ketamine analogues are rapidly emerging around the world and are considered one of the new psychoactive substances (NPS) of greatest concern. However, little is known about their actual use at the community level and their evolution on the drug market. Wastewater-based epidemiology is a useful tool to explore the profile of NPS use. Influent wastewater samples were collected from 21 cities in Southwest China between 2022 and 2023, and ketamine analogues were determined by liquid chromatography-tandem mass spectrometry. Results showed that five ketamine analogues were detected in at least one wastewater sample from 19 cities, of which four new analogues were found in wastewater for the first time. 2-fluoro deschloro-N-ethyl-ketamine (2-FDCNEK) was the most frequently detected analogue, with a population-normalized mass load of up to 3.18 mg day-1 1000 inh-1. The remaining analogues were detected less frequently, with mass loads of almost below 1 mg day-1 1000 inh-1. 2-fluoro deschloroketamine (2-FDCK), which was classified as a controlled substance in 2021, showed an evident downward trend. Furthermore, 2-(methylamino)-2-(2-methyphenyl)-cyclohexanone (2-MDCK) disappeared within a short period, whereas 2-FDCK and 2-FDCNEK persisted over the two-year observation period, suggesting that ketamine analogues containing halogen atoms on the phenyl group may have psychoactive effects similar to those of ketamine, with a high potential for abuse. These findings highlight the importance of wastewater analysis in monitoring the dynamic profile of NPS use, providing valuable information for authorities to take measures to prevent the rapid spread of NPS and minimize health risks.

Nationwide assessment of illicit drug consumption patterns in South Korea using wastewater-based epidemiology during the COVID-19 pandemic (2020-2022)

Illicit drugs have become a crucial global social issue, with South Korea experiencing a continuous increase in the number of offenders and drug smuggling. This study employed wastewater-based epidemiology to investigate consumption patterns of 8 illicit drugs and their 7 metabolites during the COVID-19 pandemic (2020-2022) in South Korea. Ten compouds were detected in the wastewater influent. Methamphetamine (METH) was prevalent in samples, followed by amphetamine and ecstasy (MDMA). Interestingly, MDMA and ketamine (KET), which were not detected in previous Korean studies conducted before COVID-19 pandemic, were detected in this study. METH exhibited the highest consumption rates, decreasing from 16.6 to 12.4 mg/day/1000 people between 2020 and 2022, while MDMA increased over the three years (mean: 1.16, 1.24, and 1.62 mg/day/1000 people in 2020, 2021, and 2022, respectively) (p < 0.05). Significant correlations were identified between regional income levels and the consumption rates of METH (p < 0.01), MDMA (p < 0.01), and KET (p < 0.05). Furthermore, METH and MDMA consumption rates in cities were positively correlated with the number of drug offenders arrested and local clubs in those cities. The findings of this study provide valuable insights into shaping regulatory policies related to illicit drugs and future studies.

Testing methods to estimate population size for wastewater treatment plants using census data: Implications for wastewater-based epidemiology

In wastewater-based epidemiology (WBE), wastewater loads are commonly reported as a per capita value. Census population counts are often used to obtain a population size to normalise wastewater loads. However, the methods used to calculate the population size of wastewater treatment plants (WWTPs) from census data are rarely reported in the WBE literature. This is problematic because the geographical extents of wastewater catchments and census area units rarely align perfectly with each other and exist at different spatial scales. This complicates efforts to estimate the number of people serviced by WWTPs in these census area units. This study compared four geospatial methods to combine wastewater catchment areas and census area units to calculate the census population size of wastewater treatment plants. These methods were applied nationally to WWTPs across New Zealand. Population estimates varied by up to 73 % between the methods, which could skew comparisons of per capita wastewater loads between sites. Variability in population estimates (relative standard deviation, RSD) was significantly higher in smaller catchments (rs = -0.727, P < .001), highlighting the importance of method selection in smaller sites. Census population estimates were broadly similar to those provided by wastewater operators, but significant variation was observed for some sites (ranging from 42 % lower to 78 % higher, RSD = 262 %). We present a widely applicable method to calculate population size from census, which involves disaggregating census area units by individual properties. The results reinforce the need for transparent reporting to maintain confidence in the comparison of WBE across sites and studies.

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

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

Exploring drug consumption patterns across varying levels of remoteness in Australia

Wastewater-based epidemiology (WBE) relies on representative sampling that is typically achieved with autosamplers that collect time, flow, or volume proportional samples. The expense, resources and operational know-how associated with autosampler operation means they are only typically available at major wastewater treatment plants (WWTPs). This results in a lack of data on consumption levels in regional and remote areas, or in countries that lack the financial means. The aim of this study was to estimate and investigate trends in drug consumption across varying levels of remoteness in Australia. Field-calibrated, microporous polyethylene passive samplers were deployed over 2 periods (Aug/Sept 2019 and 2020) at 43 treatment plants covering all five categories of remoteness, as per Australian Bureau of Statistics definitions (Major cities, Inner regional, Outer regional, Remote, and Very remote). The per capita consumption of cocaine, methylamphetamine, nicotine, oxycodone and MDMA were estimated. No spatial trends between remoteness and drug consumption were observed, except for cocaine, where Major cities had a 5-to-10-fold higher consumption compared to the other levels of remoteness in 2019 and 2020, respectively. Outer regional sites had the highest and lowest methylamphetamine consumption. The variance in drug use among sites was much higher in Remote (and Inner/Outer regional) sites when compared with Major cities. A significant and consistent decrease in oxycodone consumption was observed at all sites between 2019 and 2020, possibly related to regulatory changes and the COVID-19 pandemic where elective surgeries were suspended. The majority of sites experienced a decrease in cocaine and methylamphetamine consumption, possibly due to border restrictions or changes in supply and demand dynamics. This was the first extensive passive sampling study to assess drug consumption in urban, regional, and remote locations, demonstrating that passive samplers can facilitate extension of wastewater-based drug monitoring programs to sites where other representative sampling options are very difficult to implement.

Analysis of drug of abuse compounds using passive sampling and ultrahigh-liquid chromatography coupled to mass spectrometry

The present study proposes the monitoring of compounds of drugs of abuse through the use of passive samplers in water systems. Initially, four positive ion compounds of interest were determined according to national surveys, and then composite sampling and passive sampling were implemented using continuous-flow passive samplers containing two types of sorbents, the Empore disk and Gerstel Twister. Two study sites were established at the beginning and at the end of the middle Bogotá River basin. After 4 days, the sorbents were removed so that they could be desorbed and analyzed using UHPLC-MS in the laboratory. For the composite samples, the results were below the first calibration curve point (FCCP) of the chromatographic method, and for passive sampling, peaks of benzoylecgonine (BE) (21427.3 pg mL-1), methamphetamine (MET) (67101.5 pg mL-1), MDMA (ecstasy) (225844.8 pg mL-1) and 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) (15908.4 pg mL-1) were found. Therefore, passive sampling could be suggested as an alternative to composite sampling for the monitoring of compounds.

Investigation of New Psychoactive Substances (NPS), Other Illicit Drugs, and Drug-Related Compounds in a Taiwanese Wastewater Sample Using High-Resolution Mass-Spectrometry-Based Targeted and Suspect Screening

The proliferation of new psychoactive substances (NPSs) in recent years has posed a significant challenge to public health. Traditional monitoring methods have proven insufficient in tracking these constantly evolving substances, leading to the development of alternative approaches such as wastewater-based epidemiology (WBE). The present study aims to utilize high-resolution mass spectrometry (HRMS)-based targeted and suspect screening to profile NPS, other illicit drugs, and drug-related compounds in a Taiwanese wastewater sample. For the targeted analysis, 8 out 18 standards of illicit drugs have been identified. The suspect screening approach based on approximately 3600 substances in the SWGDRUG library can further identify 92 compounds, including opiate analgesics, synthetic cathinones, phenylalkylamines derivatives, phenethylamine derivatives, tryptamine derivatives, steroids, and ephedrine-related compounds. Additionally, the presence of 5-methoxy-2-aminoindane (MEAI) in the wastewater indicates that drug dealers have recently sold this potential NPS to evade drug regulations. This study firstly reports the HRMS-based comprehensive profile of NPS, other illicit drugs, and drug-related compounds in Taiwan, which could be applied as biomarkers for estimating the consumption of drugs.

Exploring the depth and breadth of the genomics toolbox during the COVID-19 pandemic: insights from Aotearoa New Zealand

BACKGROUND

Genomic technologies have become routine in the surveillance and monitoring of the coronavirus disease 2019 (COVID-19) pandemic, as evidenced by the millions of SARS-CoV-2 sequences uploaded to international databases. Yet the ways in which these technologies have been applied to manage the pandemic are varied.

MAIN TEXT

Aotearoa New Zealand was one of a small number of countries to adopt an elimination strategy for COVID-19, establishing a managed isolation and quarantine system for all international arrivals. To aid our response, we rapidly set up and scaled our use of genomic technologies to help identify community cases of COVID-19, to understand how they had arisen, and to determine the appropriate action to maintain elimination. Once New Zealand pivoted from elimination to suppression in late 2021, our genomic response changed to focusing on identifying new variants arriving at the border, tracking their incidence around the country, and examining any links between specific variants and increased disease severity. Wastewater detection, quantitation and variant detection were also phased into the response. Here, we explore New Zealand's genomic journey through the pandemic and provide a high-level overview of the lessons learned and potential future capabilities to better prepare for future pandemics.

CONCLUSIONS

Our commentary is aimed at health professionals and decision-makers who might not be familiar with genetic technologies, how they can be used, and why this is an area with great potential to assist in disease detection and tracking now and in the future.

Sewage analysis as an alternative tool for assessing drug of abuse and new psychoactive substances in Tunisia

Many studies attest to the pollution of wastewaters by organic molecules including drug of abuse (DAs) residues and new psychoactive substances (NPS) at trace levels. The occurrence of these emerging micropollutants in influent wastewaters (IWW) from three Tunisian Wastewater Treatment Plants (WWTPs) was assessed. Influent wastewater composite samples (24 h) were collected over 7 consecutive days in November 2019. The determination and quantification of 11 drug of abuse or their metabolites was performed by the application of an optimized multi-residue method liquid chromatography tandem mass spectrometry (LC-MS/MS). MDMA, THC and the cocaine metabolite benzoyl ecgonine were the most detected substances across the three investigated sewage plants. A new wastewater-based epidemiology (WBE) approach was applied in this study to estimate illicit drug consumption. This innovative approach was used to calculate and to assess collective drug consumption of illicit drug at a community level, based on the concentration of selected illicit substances and their major metabolites in influent wastewater. The average MDMA consumption found in the selected cities ranged between 35,8-1531,1 mg day^- 1/1000 inhabitants and increased during the weekends. Cocaine consumption varied from 24.5 to 179.8 mg day^- 1/1000 inhabitants. Complementary qualitative investigation of new psychoactive substances was monitored for the first time for an African country, examining the occurrence of 33 NPS in wastewaters samples. Out of 33 totals screened NPS across all sampling sites, 16 were tentatively identified with this approach. The 16 detected NPS covered most of the representative and used molecules of different NPS classes; including synthetic opioids, synthetic cathinones, amphetamines derivatives and synthetic cannabinoids.