Importance:Australia is leading the world in efforts to reduce tobacco use by implementing high cigarette taxes and restrictive regulations on nicotine vaping products. However, concerns have emerged that these policies may unintentionally drive the expansion of illicit tobacco and vaping markets, potentially undermining public health gains. Objectives:To assess spatial and temporal changes in total nicotine, tobacco-derived nicotine, and illicit tobacco use across Australian regions of different remoteness from 2017 to 2023. Design, Setting, and Participants:This longitudinal, cross-sectional wastewater study was performed from April 2017 to April 2023. Wastewater samples were collected from as many as 55 wastewater treatment plants (WWTPs) in Australia, including 3 remoteness levels: major cities, inner regional, and outer regional to remote areas. The selected WWTPs serve more than 50% of the Australian population. Main Outcomes and Measures:Nicotine metabolites (cotinine and hydroxycotinine) and the tobacco-specific alkaloid (anabasine) were analyzed in wastewater samples using a validated liquid-chromatography tandem mass spectrometry method. Total nicotine and tobacco-derived nicotine consumption were back-estimated. Illicit tobacco use was identified in combination with the tobacco sales data. Results:Wastewater samples collected across Australia, representing 14 million people, were analyzed for back-estimation. Total nicotine consumption declined fastest in outer regional to remote areas (-2.2% annually; 95% CI, -3.2% to -1.1%), followed by inner regional areas (-1.4% annually; 95% CI, -2.1% to -0.8%), and remained stable in major cities. By comparison, tobacco-derived nicotine consumption decreased faster in major cities (-5.0% annually; 95% CI, -8.3% to -1.9%) and inner regional areas (-9.8% annually; 95% CI, -12.5% to -7.3%) than in the outer regional to remote areas (-2.3% annually; 95% CI, -6.0% to 1.8%). Illicit tobacco use was estimated to have increased from 1350 to 3400 tons from 2017 to 2023. Conclusions and Relevance:In this cross-sectional study of wastewater surveillance in Australia, different trends of tobacco use were observed across regions, accompanied by increasing use of illicit tobacco and vaping products. These findings provide evidence for future tobacco and vaping control policies. Ongoing wastewater monitoring is essential for evaluating new tobacco and vaping product control measures implemented in 2024.

Triangulating complementary data sources can provide a more complete picture of population-level opioid use trends, both spatially and temporally. This study aimed to evaluate trends in fentanyl and oxycodone use in Australia from 2018 to 2022 using two data sources: Pharmaceutical Benefits Scheme (PBS) dispensing data and wastewater-based epidemiology (WBE), and to assess their agreement. Wastewater samples from 57 wastewater treatment plants, covering all Australian states and territories, were analyzed for biomarkers of fentanyl and oxycodone to estimate consumption. PBS claims were also converted to consumption and spatially mapped to wastewater catchments, enabling site, state, and national comparisons with WBE data. Spatially, PBS and WBE estimates showed better alignment for fentanyl than for oxycodone at both the site and state/territory levels. Temporally, there were strong correlations between PBS and WBE data for both opioids, particularly for fentanyl. PBS and WBE trends had similar decreasing rates of use of the two opioids over time. Fentanyl consumption decreased by 0.29 mg/day/1000 people per year according to PBS data, and by 0.31 mg/day/1000 people per year based on WBE estimates. Corresponding values for oxycodone were 15.36 mg/day/1000 people and 16.85 mg/day/1000 people. By integrating these complementary data sets, our study provides strong evidence of the declining trend of fentanyl and oxycodone use in Australia after stricter prescription regulation. WBE and dispensing data provide a powerful framework for comprehensive opioid monitoring to inform targeted public health interventions.

The growing emergence of new psychoactive substances (NPS) challenges traditional approaches to drug monitoring, highlighting a need for innovative surveillance strategies. We explored the potential to better understand the NPS market in Australia by combining wastewater analysis with toxicosurveillance programs. Focussing on a time of year of likely higher NPS and drug use, influent wastewater samples were collected from four Australian states (South Australia, Victoria, Queensland, and New South Wales) over the New Year period from 2019-2020 to 2024-2025. Clinical samples presenting between 15 December and 15 January each period from the toxicosurveillance systems Emerging Drugs Network of Australia (including Western Australia, South Australia, and Queensland), Emerging Drugs Network of Australia Victoria (Victoria) and Prescription, Recreational and Illicit Substance Evaluation-PRISE (New South Wales) were extracted. In total, 294 wastewater and 117 clinical samples were included in this work. A total of 46 individual NPS were found in both datasets. This included: 21 only in wastewater, 36 only in clinical, and 12 in both. Overall, 743 instances of NPS were found in all wastewater samples and 171 in clinical data. In wastewater samples, N, N-dimethylpentylone (54%), mitragynine (52%), and bromazolam (45%) were the most frequently detected. In the clinical samples, the most common were bromazolam (44%) and clonazolam (21%). Overall, synthetic cathinones and plant-based compounds were more prevalent in wastewater, and synthetic opioids and benzodiazepines in clinical samples. Differences in detected NPS classes illustrate the complementary nature of these surveillance systems. Higher wastewater concentrations may indicate broader use and lower acute harm than drugs identified clinically. Integrating these datasets with additional sources such as surveys, coronial records, police seizures, and drug-checking services can strengthen NPS monitoring.

Low- and no-calorie sweeteners (LNCS) are increasingly used as sugar substitutes in processed foods and sweetened beverages to reduce energy intake while maintaining taste. Given that poor diet remains a major contributor to non-communicable diseases, LNCS offer a strategy to lower caloric intake. However, ongoing concerns about their health effects highlight the need for a clearer understanding of LNCS exposure patterns within vulnerable groups of the population. Data on LNCS exposure and consumption trends, especially in the younger population, remain limited. Pooled urine samples were analyzed for four LNCS (acesulfame, sucralose, cyclamate, and saccharin) using Liquid Chromatography Tandem Mass Spectrometry (LC-MS/MS). Urinary concentrations were determined for various demographics (sex, age, and remoteness) to identify patterns of exposure, with focus on the younger population (< 5 years). Measured concentrations across all pools (n = 135) containing 3375 individuals ranged from 0.1 to 40 mg/L for acesulfame, 0.04-30 mg/L for saccharin, 0.01-30 mg/L for cyclamate, and 0.01-1.3 mg/L for sucralose. Saccharin showed significantly higher concentrations among children and adolescents (0-15 years) compared to adults (15-60 years). No significant differences were observed between sexes or age groups for acesulfame, cyclamate, and sucralose. LNCS concentrations did not vary significantly by remoteness. Esti-mated average daily saccharin intake was 600 μg/kgbw/day for children aged 0-5 years, representing 12% of the acceptable daily intake (ADI), compared to 25 μg/kgbw/day (0.5% of ADI) in adults. In the case of saccharin, the highest concentrations were observed in young children, which may represent a higher risk of potential adverse health outcomes. Average urinary concentrations of all LNCS were determined, serving as indicators of average population intake.

Ketamine is an anaesthetic drug with dissociative effects and is used in hospitals and for emergency treatment. Over the past four years, there has been increasing interest in the non-medical (recreational) use of ketamine in Australia. This study aimed to interrogate patterns in ketamine loads found in wastewater in Australia between December 2020 and April 2025. Daily influent wastewater samples were collected from up to 50 wastewater treatment plants over a week across state and territory capital city and regional sites every 4 months from all states and territories of Australia covering on average 53% of the total population. Wastewater was concentrated using solid phase extraction followed by quantitative analysis using liquid chromatography tandem mass spectrometry to determine concentrations of the metabolite norketamine, with final concentrations flow and population normalised to units of excreted mg/day/1000 people. Norketamine excreted mass loads were compared with regionality and socioeconomic status. Considering the intended application, substantially higher mass loads of norketamine on weekends compared to weekdays would suggest the non-medical use of ketamine at weekends. Nationally, norketamine mass loads were higher for sites located in major city areas compared to those in ‘inner’ and ‘outer’ regional Australia. In addition, sites with higher socioeconomic status had higher mass loads of norketamine. Overall, norketamine mass loads have been increasing in Australia from 2022 to 2025, particularly in sites with higher socioeconomic status. This study demonstrates the value of ongoing wastewater monitoring, revealing both within-week and long-term shifts in ketamine excreted loads in Australia.

Consumption of psychotropic drugs is a major economic and public health challenge in Australia. Wastewater-based epidemiology (WBE) and drug checking have emerged as complementary tools to monitor this market. WBE estimates drug use within communities for target compounds and their metabolites, while drug checking is a free service available in some Australian jurisdictions, which allows individuals to verify drug purity and composition. In this work, wastewater samples were collected from five sites across Queensland (n = 3), New South Wales (n = 1) and Victoria (n = 1) over the 2024-25 New Year holidays, while drug checking was carried out at a site in central Canberra over December-January. Wastewater samples were analysed for alcohol, illicit drugs and new psychoactive substances (NPS) using liquid chromatography-tandem mass spectrometry. Methamphetamine was the most consumed illicit substance across all sites, while cocaine and MDMA showed distinct increases over the New Year period. Among NPS, bromazolam and 2'-fluoro-2-oxo-PCE were most prevalent, while ketamine was consistently detected at regional sites with consumption 2.8-3-fold higher on New Year's days. Drug checking revealed prevalence of MDMA, cocaine and ketamine. NPS were detected in 15%-20% of total drug samples submitted, with N,N-dimethylpentylone and 2'-fluoro-2-oxo-PCE the most frequently found. This study is the first to demonstrate the potential synergy between WBE and drug checking, highlighting how their complementary roles can enhance drug surveillance, early warnings for emerging psychoactive substances and monitoring of changes in drug consumption during high-risk periods.

New psychoactive substances (NPS) are a continuously evolving class of psychoactive compounds, marketed initially as legal alternatives to conventional illicit drugs while bypassing legal regulations and, as such, are of international public health concern. Due to their continuous evolution, with new derivatives continually appearing on the drug market, monitoring and surveillance of NPS pose a challenge when employing traditional socio-epidemiological methods. In this study, we applied wastewater-based epidemiology (WBE) to gain additional information on the spatiotemporal consumption patterns of NPS. Samples of influent wastewater were collected from seven wastewater treatment plants (WWTPs) in Slovenia throughout six sampling periods, covering the pre- and during-pandemic periods (summer 2019, winter/spring 2020 and winter/spring 2021), and when most of the restrictions had been eased (spring 2022) due to the COVID-19 pandemic. Following solid-phase extraction, pooled samples were analysed using two separate methods: a targeted LC-MS/MS method for NPS analysis and suspect screening using LC-QTOF-MS in combination with the HighResNPS database of >2000 NPS and other compounds of toxicological relevance. Five NPS (3-methylmethcathinone (3-MMC), 4-fluoroamphetamine (4-FA), eutylone, mephedrone, and mitragynine) were semi-quantified across all sites. 3-MMC and mitragynine were the most prevalent NPS detected, with the latter having the highest population-normalised mass loads (up to 40 mg/day/1000 inhabitants). A noticeable increase in 3-MMC mass loads was observed during the pandemic. Following suspect screening, 17 additional compounds were detected at least once across all sites. This study highlights the potential for WBE to provide insight into Slovenia’s NPS market.

BACKGROUND AND AIMS:This study examined whether socio-economic status (SES) and geographic remoteness are associated with cannabis consumption across Australia by comparing wastewater-based surveillance (WBS) data and self-reported cannabis use in national household surveys. METHODS:We compared cannabis consumption estimates from 6 years of wastewater data from the National Wastewater Drug Monitoring Program (NWDMP) with cannabis use data from the National Drug Strategy Household Survey (NDSHS). We categorised the Index of Relative Socio-economic Advantage and Disadvantage (IRSAD) into quartiles for each wastewater catchment area. Three remoteness categories (Major Cities, Inner Regional, Outer Regional/Remote) from the Australian Bureau of Statistics were used to categorise wastewater and survey data by degree of urbanisation. Trends were analysed using linear regression, analysis of variance and logistic regression. RESULTS:Wastewater: Estimated cannabis consumption in wastewater increased between 2018 and 2025 annually across SES quartiles from 2.9% [95% confidence interval (CI) = 2.0-3.9%] for the most disadvantaged to 5.2% (95% CI = 3.2-7.3%) for the second most disadvantaged quartile. The annual rates increased for all three categories of remoteness and ranged from 3.6% (95% CI = 2.2-5.2%) to 4.8% (95% CI = 4.2-5.5%) for Inner Regional and Major Cities, respectively. Consumption was statistically significantly higher in the most disadvantaged SES quartile (3000 mg/1000 people/day, 95% CI = 2900-3100) than in the least disadvantaged (1200 mg/1000 people/day, 95% CI = 1100-1200, P < 0.001). It was also highest in the most remote category (2400 mg/1000 people/day, 95% CI = 2300-2500), compared with the most urban category (980 mg/1000 people/day, 95% CI = 960-1000, P < 0.001). SURVEY:In the NDSHS the prevalence of regular cannabis use was higher in the most disadvantaged SES quintile (6.1%, 95% CI = 5.2-7.3% in 2022/2023) than in the least disadvantaged (4.2%, 95% CI = 3.5-5.1% in 2022/2023). It was also higher in the most remote category (5.9%, 95% CI = 4.8-7.4%) than in the most urban category (4.3%, 95% CI = 3.9-4.8%), in all survey years (i.e. 2016 and 2019). CONCLUSIONS:Wastewater-based surveillance and survey data describe similar trends in population cannabis use by socio-economic status and urban remoteness in Australia from 2018 to 2025.

BACKGROUND AND AIMS:To evaluate changes in community consumption and wholesales of alcohol before and after alcohol restrictions were implemented in 2023, aimed at reducing alcohol-related crime and violence. DESIGN:Longitudinal observational study. SETTING:Alice Springs, a regional town in the Northern Territory, Australia, from December 2019 to February 2024. PARTICIPANTS:The population of Alice Springs serviced by the wastewater treatment plant catchment, and wholesales data for Alice Springs. MEASUREMENTS:Community consumption of alcohol was measured by analysing a biomarker of alcohol consumption in wastewater before and after the alcohol restrictions were implemented. Quarterly alcohol wholesales for the region were also modelled. FINDINGS:After the restrictions, alcohol consumption in Alice Springs immediately decreased, with an average 26% decrease over 12 months [95% confidence interval (CI) = -31 to -22%]. No statistically significant difference in trend slope was observed. The largest decreases in alcohol consumption were for Mondays and Tuesdays, when takeaway alcohol sales were not allowed. Total alcohol wholesales decreased by 17% (95% CI = -31 to -22%), with greatest meaningful declines of 44% for the sales of spirits (95% CI = -50 to -36%). CONCLUSIONS:After the implementation of the 2023 restrictions on alcohol sales in the Northern Territory, Australia, wastewater-based estimates of alcohol consumption in Alice Springs were statistically significantly reduced by 26% and this was sustained for one year until the end of the data series in 2024. Total alcohol wholesales were also reduced, with differences observed by beverage type.

BACKGROUND AND AIMS:The use of new synthetic opioids, such as the highly potent 2-benzylbenzimidazoles (i.e. nitazene) drugs, is a global health concern because of their increased risk of fatal overdose. In the early 2020s, nitazene analogues were linked to significant numbers of overdoses in the United States. Their reach is now worldwide, with nitazene overdose deaths reported in Europe, Australia and New Zealand. The aim of this study was to measure quantities of nitazenes in wastewater samples collected from 68 locations in 22 countries, covering six continents, to understand and estimate their use. METHODS:Untreated influent wastewater samples were collected over a one-week period that included the New Year period in 2022-2023 and 2023-2024. Samples were collected from 22 countries: Australia, Austria, Belgium, Brazil, Canada, Chile, China, Cyprus, Czechia, France, Germany, Greece, Iceland, Italy, New Zealand, Nigeria, Republic of Korea, Slovenia, Spain, Sweden, United Kingdom and United States. Samples were loaded onto solid-phase extraction cartridges in the country of collection and sent to Australia for elution and analysis using sensitive liquid chromatography-mass spectrometry methods. RESULTS:A total of 683 individual wastewater samples were analysed across the two years: 339 in 2022-2023 and 344 in 2023-2024. Two nitazene analogues-protonitazene and N-pyrrolidino etonitazene (etonitazepyne)-were found in five separate sites in the United States and Australia. In the 2022-2023 period, protonitazene was found in two sites in the United States. The following year, protonitazene was detected in two further sites in the United States, while both protonitazene and etonitazepyne were found in one site in Australia. Protonitazene mass loads ranged between 0.3 mg/day/1000 people and 100 mg/day/1000 people. Etonitazepyne was also found at mass loads between 0.2-2 mg/day/1000 people). CONCLUSIONS:A very high mass load of protonitazene was calculated, using wastewater analysis, for the day of 30 December 2023 in one site in Australia. Etonitazepyne showed the same trend from a lower base. Wastewater-based nitazene surveillance shows promise as a form of both drug early warning and ongoing monitoring of trends in use, especially as a complementary tool to existing surveillance methods.

New psychoactive substances are a group of synthetic or naturally occurring drugs that mimic the effects of controlled illicit drugs. With limited information around potency, effects and health risks, there is international concern around their use and thus surveillance efforts are needed for public health. This study presents a global assessment of new psychoactive substances in influent wastewater from 52 sites across 20 countries during the 2022/2023 New Year period. Using solid-phase extraction followed by liquid chromatography-tandem mass spectrometry, 21 new psychoactive substances were detected with mitragynine, 3-methylmethcathinone, and eutylone being the most prevalent. Notably, 3,4-methylenedioxy-PV8 was identified for the first time in sites in Australia and the United States. A retrospective analysis of population normalised mass loads for 3-methylmethcathinone at European sites revealed downward trends in 2022/2023 sampling period compared to the previous years, suggesting a possible impact of regional scheduling measures. Additionally, this work demonstrates the stability of new psychoactive substances in loaded cartridges for up to four months when stored at -20 °C. These findings highlight the value of wastewater-based epidemiology for global monitoring of emerging new psychoactive substances threats and policy evaluation.

Phenibut is a new psychoactive substance (NPS) first synthesized in Russia in 1963 as a derivative of gamma-aminobutyric acid. Originally developed for therapeutic use, it has gained popularity for nonmedical purposes, including recreational and cognitive enhancement. In Brazil, phenibut is uncontrolled and easily purchased online. This study used wastewater-based epidemiology (WBE) to investigate phenibut use patterns in two northeastern Brazilian cities. Composite daily wastewater samples were collected from two treatment plants (WWTPs), Recife (WWTPA) and Olinda (WWTPB), during two periods in 2023: Carnival and a reference week. Samples underwent solid-phase extraction (SPE) and analysis by liquid chromatography-tandem mass spectrometry (LC-MS/MS). Phenibut concentrations were converted to population-normalized mass loads (PNMLs, mg/day/1000 inhabitants). The highest phenibut levels and PNMLs (up to 4.06 mg/day/1000 inhabitants) occurred during Carnival at WWTPA, located in a major tourist area, suggesting recreational use. During the reference week, PNMLs ranged from detection limits to 2.29 mg/day/1000 inhabitants on weekdays, indicating possible functional or cognitive enhancement use. These findings reveal two distinct use patterns: recreational peaks during Carnival weekends and possible functional use on weekdays outside festive periods. This is the first evidence of phenibut detection in Brazilian wastewater and its temporal use patterns. The results highlight WBE's value in monitoring NPS trends and suggest recreational use predominates during large events. This underscores the need for public health attention and regulatory monitoring of uncontrolled substances with abuse potential.

One of the primary criteria for a suitable drug biomarker for wastewater-based epidemiology (WBE) is having a unique source representing human metabolism. For WBE studies, this means it is important to identify and monitor metabolites rather than parent drugs, to capture consumption of drugs and not fractions that could be directly disposed. In this study, a high-throughput workflow based on a human liver S9 fraction in vitro metabolism assay was developed to identify human transformation products of new chemicals, using α-pyrrolidino-2-phenylacetophenone (α-D2PV) as a case study. Analysis by liquid chromatography coupled to high resolution mass spectrometry identified four metabolites. Subsequently, a targeted liquid chromatography – tandem mass spectrometry method was developed for their analysis in wastewater samples collected from a music festival in Australia. The successful application of this workflow opens the door for future work to better understand the metabolism of chemicals and their detection and application for wastewater-based epidemiology.

The widespread presence of emerging contaminants in water systems has raised concern for the scientific community and policy makers, as they can cause harmful effects on the ecosystem and human life. This group of compounds includes illicit drugs, pharmaceuticals, personal care products, pesticides, microplastics, phthalates, and poly- and perfluoroalkyl substances (PFAS), among others. A significant number of these compounds are present in influent wastewater at various concentration levels from ng/L to mg/L, because of household and industry discharges and other sources. The wastewater treatment plants are not designed to remove all these compounds and, thus, their emission into the aquatic system is a real possibility. This chapter is focused on the removal efficiencies of various classes of chemical compounds in WWTPs by physical technologies (e.g., adsorption and filtration), chemical technologies (e.g., oxidation, ozonation, and advanced oxidation processes), biological technologies (e.g., activated sludge, membrane bioreactor, aerobic bioreactor, and anaerobic bioreactor) and hybrid systems. It studies the occurrence of some of the most used compounds in influent wastewater and their removal according to different treatment technologies. It is very important to collect data on the fate of emerging contaminants through WWTPs, in order to improve the wastewater treatment plants technologies and to take measures to protect the ecosystem and human health.

During the COVID-19 pandemic, one of Australia's biggest cities, Melbourne, experienced three major isolation ("lockdown") periods in 2020 (160 days) and in 2021 (111 days) which makes it one of the most locked down cities world-wide. This study assessed how the pandemic affected temporal trends in methamphetamine, MDMA and cocaine consumption using wastewater-based epidemiology. Daily samples were collected for most of 2020 and 2021 (n = 660 days). Concentrations were measured using direct-injection LC-MS/MS and back-calculated to consumption estimates. Results indicate that methamphetamine use was increasing before the first lockdown and decreased after the end of the first lockdown in 2020. Methamphetamine trends appeared to have remained steady throughout the second lockdown period before increasing steeply after it ended. For most of 2020, cocaine use remained steady, with an increase after the second lockdown. MDMA use decreased after the start of the first lockdown and remained steady throughout most of 2020 and 2021. In comparison to 2020, trends in 2021 were less variable and stimulant use did not appear to be as associated with COVID-19 restrictions. Overall, this study was able to show the impact of lockdown periods and the related social restrictions on illicit stimulant use. ENVIRONMENTAL IMPLICATION: Illicit drugs are hazardous chemicals, of concern both to humans and the environment. While studies have been undertaken to understand their temporal trends, this work utilizes wastewater-based epidemiology and daily sampling to provide a comprehensive understanding of the impact of the COVID-19 pandemic on the use of methamphetamine, MDMA and cocaine on one of the most locked-down cities in the world. Understanding the consequences of this significant intervention on illicit drug use could provide valuable insights into its potential environmental impact.

BACKGROUND AND AIMS:Between 2018 and 2020, Australia implemented major policy changes to improve the quality and safety of opioid prescribing, with a specific focus on oxycodone. This study used wastewater-based epidemiology to assess the efficacy of Australia's regulatory reforms by measuring change in consumption of oxycodone via exploratory analysis. DESIGN, SETTING, PARTICIPANTS, MEASUREMENTS:Wastewater analysis data on oxycodone consumption was from the National Wastewater Drug Monitoring Program. The program captures data from more than 50 wastewater treatment plant catchments across Australia, equivalent to more than 50% of the national population. Geographic trend analyses were conducted for both major cities and regional areas within all states and territories of Australia over a 6-year period between 2017 and 2023. FINDINGS:Oxycodone consumption showed a statistically significant increase nationally from 78 mg/day/1000 people (95% confidence interval [CI] = 71, 84) in 2017 to 120 mg/day/1000 people in August 2019 (95% CI = 110, 120), an increase of 52% (95% CI = 42, 62, P < 0.0001). From August 2019 to December 2020, there was a statistically significant decrease from 120 to 65 mg/day/1000 people (95% CI = 60, 71), a decrease of 45% (95% CI = 40, 51), followed by a modest 2.4% increase to the end of the study period in April 2023 (95% CI [2.0,2.7]). CONCLUSIONS:A 45% reduction in oxycodone consumption in Australia from 2019 to 2020 coincided with national policy changes that aimed to reduce consumption of prescription opioids. The overall declining trend in consumption was suggestive of the effectiveness of national interventions in reducing pharmaceutical opioid use. Wastewater-based epidemiology provides an effective approach for assessing the effectiveness of controlled substances policy changes.

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

BACKGROUND:New psychoactive substances (NPS) are of public health concern due to their sporadic proliferation and the dearth of information on toxicity when consumed. In addition to seized data from forensic and toxicology reporting, wastewater analysis serves as a complimentary tool for NPS surveillance. A method to detect 71 NPS by simple filtration followed by liquid-chromatography tandem mass spectrometry was developed to detect multiclass NPS consisting of arylcyclohexylamines, designer benzodiazepines, synthetic cannabinoids, synthetic opioids, phenethylamines, synthetic cathinones, tryptamines, and indole alkaloids. RESULTS:In this work, the influential factors for electrospray ionisation were identified and optimised using the fractional factorial design and face-centred central composite design, respectively. The filtration loss during sample clean-up was assessed for all compounds. The final method was validated and applied to wastewater collected from a music festival held in Queensland in 2022. The validated method had linearity between 0.5 ng L-1 and 5000 ng L-1, the limit of quantification (LOQ) ranges from 0.6 ng L-1 to 70 ng L-1, precision within ±20 %, accuracy ranges from 70 % to 120 %, and matrix effect ranges from soft (0 %-20 %) to medium (20 %-50 %) for the majority of the compounds. NPS detected in the festival were 2-fluorodeschloroketamine, 7-hydroxymitragynine, mitragynine, N,N-dimethylpentylone, pentylone, phenibut, and O-desmethyltramadol. SIGNIFICANCE:Systematic electrospray ionisation optimisation using the design of experiment for a large method is practical and provides in-depth chemical information on studied compounds. The optimised method demonstrated the applicability of analysing samples collected from a festival in this work.

BackgroundWastewater analysis provides a complementary measure of alcohol use in whole communities. We assessed absolute differences and temporal trends in alcohol consumption by degree of remoteness and socioeconomics indicators in Australia from 2016 to 2023.MethodsAlcohol consumption estimates from 50 wastewater treatment plants (WWTP) in the Australian National Wastewater Drug Monitoring Program were used. Trends were analysed based on 1) site remoteness: Major Cities, Inner Regional and a combined remoteness category of Outer Regional and Remote, and 2) using two socioeconomic indexes from the Australian Bureau of Statistics (ABS) relating to advantage and disadvantage for Income, education, occupation, and housing.ResultsConsumption estimates were similar for Major Cities and Inner Regional areas (14.3 and 14.4L/day/1000 people), but significantly higher in Outer Regional and Remote sites (18.6L/day/1000 people). Consumption was decreasing in Major cities by 4.5% annually, Inner Regional by 2.4%, and 3.5% in the combined Outer Regional and Remote category. Consumption estimates were higher in socioeconomically advantaged quartiles than those of lower advantage (0%-25% mean = 13.0, 75%-100% mean = 17.4). Consumption in all quartiles decreased significantly over the 7 year period with annual rates of decrease of 0.9%, 3.7%, 3.6%, and 3.0% for the lowest to highest quartile, respectively.ConclusionsDeclines in Australian alcohol consumption have been steeper in large urban areas than regional and remote areas. There were smaller annual decreases in the most socioeconomically disadvantaged areas. If continued, these trends may increase Australian health inequalities. Policy and prevention work should be appropriately targeted to produce more equitable long-term outcomes.