Increased Nicotine Consumption in Australia During the First Months of the COVID-19 Pandemic.

INTRODUCTION: Mixed findings have been reported about the impact of the COVID-19 pandemic on smoking behavior in different populations. AIMS AND METHODS: In this study, we aimed to quantify changes in smoking prevalence through the proxy of nicotine consumption in the Australian population from 2017 to 2020 inclusive. Estimates of nicotine consumption between 2017 and 2020 were retrieved from a national wastewater monitoring program that covers up to 50% of the Australian population. National sales data for nicotine replacement therapy (NRT) products from 2017 to 2020 were also acquired. Linear regression and pairwise comparison were conducted to identify data trends and to test differences between time periods. RESULTS: The average consumption of nicotine in Australia decreased between 2017 and 2019 but increased in 2020. Estimated consumption in the first half of 2020 was significantly higher (~30%) than the previous period. Sales of NRT products increased gradually from 2017 to 2020 although sales in the first half of the year were consistently lower than in the second half. CONCLUSION: Total nicotine consumption increased in Australia during the early stage of the pandemic in 2020. Increased nicotine consumption may be due to people managing higher stress levels, such as from loneliness due to control measures, and also greater opportunities to smoke/vape while working from home and during lockdowns in the early stage of the pandemic. IMPLICATIONS: Tobacco and nicotine consumption have been decreasing in Australia but the COVID-19 pandemic may have temporarily disrupted this trend. In 2020, the higher impacts of lockdowns and working from home arrangements may have led to a temporary reversal of the previous downward trend in smoking during the early stage of the pandemic.

Prediction of Retention Time and Collision Cross Section (CCSH+, CCSH-, and CCSNa+) of Emerging Contaminants Using Multiple Adaptive Regression Splines.

Ultra-high performance liquid chromatography coupled to ion mobility separation and high-resolution mass spectrometry instruments have proven very valuable for screening of emerging contaminants in the aquatic environment. However, when applying suspect or nontarget approaches (i.e., when no reference standards are available), there is no information on retention time (RT) and collision cross-section (CCS) values to facilitate identification. In silico prediction tools of RT and CCS can therefore be of great utility to decrease the number of candidates to investigate. In this work, Multiple Adaptive Regression Splines (MARS) were evaluated for the prediction of both RT and CCS. MARS prediction models were developed and validated using a database of 477 protonated molecules, 169 deprotonated molecules, and 249 sodium adducts. Multivariate and univariate models were evaluated showing a better fit for univariate models to the experimental data. The RT model (R2 = 0.855) showed a deviation between predicted and experimental data of ±2.32 min (95% confidence intervals). The deviation observed for CCS data of protonated molecules using the CCSH model (R2 = 0.966) was ±4.05% with 95% confidence intervals. The CCSH model was also tested for the prediction of deprotonated molecules, resulting in deviations below ±5.86% for the 95% of the cases. Finally, a third model was developed for sodium adducts (CCSNa, R2 = 0.954) with deviation below ±5.25% for 95% of the cases. The developed models have been incorporated in an open-access and user-friendly online platform which represents a great advantage for third-party research laboratories for predicting both RT and CCS data.

Harnessing the Power of the Census: Characterizing Wastewater Treatment Plant Catchment Populations for Wastewater-Based Epidemiology.

Wastewater studies that provide per capita estimates of consumption (influent) or release (effluent) via wastewater systems rely heavily on accurate population data. This study evaluated the accuracy of Wastewater Treatment Plant (WWTP) reported populations, as well as hydrochemical parameters, against accurate populations from a population census. 104 catchment maps were received from WWTPs, geolocated in geospatial software and overlaid with the smallest area unit of the Australian census, equating to 14.9 million Australians or 64% of the national population. We characterized each catchment for population counts, as well as by age profile, income profile, and education level. For a subset of sites, population estimates using hydrochemical parameters BOD, COD, and dissolved ammonia were evaluated for accuracy against census populations. Population estimates provided by WWTP personnel were on average 18% higher than census-based populations. Furthermore, hydrochemical-based population estimates had high RSD (>44%) for BOD, COD, and ammonium between sites, suggesting that their applicability for use in population estimation may not be appropriate for every WWTP. Catchment age distributions were evaluated and 46% of catchments had skewed age distributions: 6% were skewed older, and 40% were skewed younger. Through this process WWTP catchment populations can be characterized in a way that will enhance the interpretations of per capita estimates.

Qualitative and quantitative temporal analysis of licit and illicit drugs in wastewater in Australia using liquid chromatography coupled to mass spectrometry.

The combination of qualitative and quantitative bimonthly analysis of pharmaceuticals and illicit drugs using liquid chromatography coupled to mass spectrometry is presented. A liquid chromatography-quadrupole time of flight instrument equipped with Sequential Window Acquisition of all THeoretical fragment-ion spectra (SWATH) was used to qualitatively screen 346 compounds in influent wastewater from two wastewater treatment plants in South Australia over a 14-month period. A total of 100 compounds were confirmed and/or detected using this strategy, with 61 confirmed in all samples including antidepressants (amitriptyline, dothiepin, doxepin), antipsychotics (amisulpride, clozapine), illicit drugs (cocaine, methamphetamine, amphetamine, 3,4-methylenedioxymethamphetamine (MDMA)), and known drug adulterants (lidocaine and tetramisole). A subset of these compounds was also included in a quantitative method, analyzed on a liquid chromatography-triple quadrupole mass spectrometer. The use of illicit stimulants (methamphetamine) showed a clear decrease, levels of opioid analgesics (morphine and methadone) remained relatively stable, while the use of new psychoactive substances (methylenedioxypyrovalerone (MDPV) and Alpha PVP) varied with no visible trend. This work demonstrates the value that high-frequency sampling combined with quantitative and qualitative analysis can deliver. Graphical abstract Temporal analysis of licit and illicit drugs in South Australia.

Prediction of Collision Cross-Section Values for Small Molecules: Application to Pesticide Residue Analysis.

The use of collision cross-section (CCS) values obtained by ion mobility high-resolution mass spectrometry has added a third dimension (alongside retention time and exact mass) to aid in the identification of compounds. However, its utility is limited by the number of experimental CCS values currently available. This work demonstrates the potential of artificial neural networks (ANNs) for the prediction of CCS values of pesticides. The predictor, based on eight software-chosen molecular descriptors, was optimized using CCS values of 205 small molecules and validated using a set of 131 pesticides. The relative error was within 6% for 95% of all CCS values for protonated molecules, resulting in a median relative error less than 2%. In order to demonstrate the potential of CCS prediction, the strategy was applied to spinach samples. It notably improved the confidence in the tentative identification of suspect and nontarget pesticides.

Monitoring a large number of pesticides and transformation products in water samples from Spain and Italy.

Assessing the presence of pesticides in environmental waters is particularly challenging because of the huge number of substances used which may end up in the environment. Furthermore, the occurrence of pesticide transformation products (TPs) and/or metabolites makes this task even harder. Most studies dealing with the determination of pesticides in water include only a small number of analytes and in many cases no TPs. The present study applied a screening method for the determination of a large number of pesticides and TPs in wastewater (WW) and surface water (SW) from Spain and Italy. Liquid chromatography coupled to high-resolution mass spectrometry (HRMS) was used to screen a database of 450 pesticides and TPs. Detection and identification were based on specific criteria, i.e. mass accuracy, fragmentation, and comparison of retention times when reference standards were available, or a retention time prediction model when standards were not available. Seventeen pesticides and TPs from different classes (fungicides, herbicides and insecticides) were found in WW in Italy and Spain, and twelve in SW. Generally, in both countries more compounds were detected in effluent WW than in influent WW, and in SW than WW. This might be due to the analytical sensitivity in the different matrices, but also to the presence of multiple sources of pollution. HRMS proved a good screening tool to determine a large number of substances in water and identify some priority compounds for further quantitative analysis.

Comparison of pharmaceutical, illicit drug, alcohol, nicotine and caffeine levels in wastewater with sale, seizure and consumption data for 8 European cities.

BACKGROUND: Monitoring the scale of pharmaceuticals, illicit and licit drugs consumption is important to assess the needs of law enforcement and public health, and provides more information about the different trends within different countries. Community drug use patterns are usually described by national surveys, sales and seizure data. Wastewater-based epidemiology (WBE) has been shown to be a reliable approach complementing such surveys. METHOD: This study aims to compare and correlate the consumption estimates of pharmaceuticals, illicit drugs, alcohol, nicotine and caffeine from wastewater analysis and other sources of information. Wastewater samples were collected in 2015 from 8 different European cities over a one week period, representing a population of approximately 5 million people. Published pharmaceutical sale, illicit drug seizure and alcohol, tobacco and caffeine use data were used for the comparison. RESULTS: High agreement was found between wastewater and other data sources for pharmaceuticals and cocaine, whereas amphetamines, alcohol and caffeine showed a moderate correlation. methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) and nicotine did not correlate with other sources of data. Most of the poor correlations were explained as part of the uncertainties related with the use estimates and were improved with other complementary sources of data. CONCLUSIONS: This work confirms the promising future of WBE as a complementary approach to obtain a more accurate picture of substance use situation within different communities. Our findings suggest further improvements to reduce the uncertainties associated with both sources of information in order to make the data more comparable.

Screening of pharmaceuticals and illicit drugs in wastewater and surface waters of Spain and Italy by high resolution mass spectrometry using UHPLC-QTOF MS and LC-LTQ-Orbitrap MS.

The existence of pharmaceuticals and illicit drugs (PIDs) in environmental waters has led many analytical chemists to develop screening methods for monitoring purposes. Water samples can contain a huge number of possible contaminants, commonly at low concentrations, which makes their detection and identification problematic. Liquid chromatography coupled with high resolution mass spectrometry (LC-HRMS) has proven itself effective in the screening of environmental contaminants. The present work investigates the use of the most popular HRMS instruments, quadrupole time-of-flight and linear trap quadrupole-Orbitrap, from two different laboratories. A suspect screening for PIDs was carried out on wastewater (influent and effluent) and surface water samples from Castellón, Eastern Spain, and Cremona, Northern Italy, incorporating a database of 107 PIDs (including 220 fragment ions). A comparison between the findings of both instruments and of the samples was made which highlights the advantages and drawbacks of the strategies applied in each case. In total, 28 compounds were detected and/or identified by either/both instruments with irbesartan, valsartan, benzoylecgonine and caffeine being the most commonly found compounds across all samples.

LC-QTOF MS screening of more than 1,000 licit and illicit drugs and their metabolites in wastewater and surface waters from the area of Bogotá, Colombia.

A large screening of around 1,000 emerging contaminants, focused on licit and illicit drugs and their metabolites, has been made in urban wastewaters (both influent and effluent) and surface waters from the area of Bogotá, Colombia. After a simple generic solid-phase extraction (SPE) step with Oasis hydrophilic-lipophilic balanced (HLB) cartridges, analyses were made by ultra high-performance liquid chromatography coupled to quadrupole time-of-flight mass spectrometry (UHPLC-QTOF MS) under MS(E) mode (sequential acquisition of mass spectra at low energy (LE) and high collision energy (HE)). Accurate mass measurements and the information provided by MS(E) on the presence of the (de)protonated molecule and fragment ions allowed the reliable identification of the compounds detected, even without reference standards being available in some cases (tentative identification). The compounds most frequently found were acetaminophen/paracetamol, carbamazepine and its dihydro-dihydroxylated metabolite, clarithromycin, diclofenac, ibuprofen, gemfibrozil, lincomycin, losartan, valsartan, the two metabolites of metamizole (4-acetamido-antipyrine and 4-formylamino-antipyrine), sucralose, and cocaine and its main metabolite benzoylecgonine. Caffeine, the sweetener saccharin, and two hydroxylated metabolites of losartan were tentatively identified in almost all samples analyzed. Pharmaceutical lidocaine was tentatively identified and subsequently confirmed with reference standard. For the first time, a general overview of the occurrence of drugs and their metabolites in the aquatic environment of Colombia has been reported. In the near future, target methodologies, typically based on liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS), will need to be set up for accurate and sensitive quantification of the contaminants selected on the basis on the information provided in the present paper.

Application of design of experiment for quantification of 71 new psychoactive substances in influent wastewater.

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.

Improving wastewater-based epidemiology for new psychoactive substance surveillance by combining a high-throughput in vitro metabolism assay and LC-HRMS metabolite identification.

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.

Wastewater-based monitoring of the nitazene analogues: First detection of protonitazene in wastewater.

Synthetic opioids, particularly the nitazene analogues class, have become a public health concern due to their high potency. Wastewater-based epidemiology can detect community use of these compounds. The objective of this work was to detect nitazene analogues in wastewater from samples collected from eight sites in the United States. Influent wastewater samples were collected from eight sites in seven states (Arizona, Oregon, New Mexico, Illinois, New Jersey, Washington and Georgia) in the United States. Samples were collected from each site on three days between 27 December 2022 and 4 January 2023, acidified on collection, stored frozen and shipped to Arizona State University (Tempe, AZ) for sample processing. Samples were then shipped to The University of Queensland (Brisbane, Australia) for sample analysis. Protonitazene was found in samples collected from two sites in Washington and Illinois. The concentration was estimated up to 0.5 ng/L, with estimated excreted mass loads up to 0.3 mg/day/1000 people. This work has shown that it is possible to detect nitazene analogues in wastewater using a combination of sample pre-concentration and sensitive instrumentation, thereby further expanding the utility of wastewater-based epidemiology.

Seven-years of alcohol consumption in Australia by wastewater analysis: Exploring patterns by remoteness and socioeconomic factors.

BACKGROUND: Wastewater 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. METHODS: Alcohol 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. RESULTS: Consumption 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. CONCLUSIONS: Declines 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.

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

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

Wastewater-based evaluation of the efficacy of oxycodone regulations in Australia.

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.

Assessing daily patterns in stimulant use during the COVID-19 pandemic in Melbourne, Australia using wastewater analysis.

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.

Characterising differences between self-reported and wastewater-identified drug use at two consecutive years of an Australian music festival.

BACKGROUND: In the context of drug prohibition, potential adulteration and variable purity pose additional health risks for people who use drugs, with these risks often compounded by the outdoor music festival environment. Ahead of the imminent implementation of drug checking services in Queensland, Australia, this study aims to characterise this problem using triangulated survey and wastewater data to understand self-reported and detected drug use among attendees of a multi-day Queensland-based music festival in 2021 and 2022. METHODS: We administered an in-situ survey focusing on drug use at the festival to two convenience samples of 136 and 140 festival attendees in 2021 and 2022 respectively. We compared survey findings to wastewater collected concurrently from the festival's site-specific wastewater treatment plant, which was analysed using Liquid Chromatography Tandem Mass Spectrometry. RESULTS: Most survey respondents (82 % in 2021, 92 % in 2022) reported using or intending to use an illicit drug at the festival. Some respondents reported potentially risky drug use practices such as using drugs found on the ground (2 % in 2021, 4 % in 2022). Substances detected in wastewater but not surveys include MDEA, mephedrone, methylone, 3-MMC, alpha-D2PV, etizolam, eutylone, and N,N-dimethylpentylone. CONCLUSION: Many substances detected in wastewater but not self-reported in surveys likely represent substitutions or adulterants. These findings highlight the benefits of drug checking services to prevent harms from adulterants and provide education on safer drug use practices. These findings also provide useful information on socio-demographic characteristics and drug use patterns of potential users of Queensland's future drug checking service.

Workflow to facilitate the detection of new psychoactive substances and drugs of abuse in influent urban wastewater.

The complexity around the dynamic markets for new psychoactive substances (NPS) forces researchers to develop and apply innovative analytical strategies to detect and identify them in influent urban wastewater. In this work a comprehensive suspect screening workflow following liquid chromatography - high resolution mass spectrometry analysis was established utilising the open-source InSpectra data processing platform and the HighResNPS library. In total, 278 urban influent wastewater samples from 47 sites in 16 countries were collected to investigate the presence of NPS and other drugs of abuse. A total of 50 compounds were detected in samples from at least one site. Most compounds found were prescription drugs such as gabapentin (detection frequency 79%), codeine (40%) and pregabalin (15%). However, cocaine was the most found illicit drug (83%), in all countries where samples were collected apart from the Republic of Korea and China. Eight NPS were also identified with this protocol: 3-methylmethcathinone 11%), eutylone (6%), etizolam (2%), 3-chloromethcathinone (4%), mitragynine (6%), phenibut (2%), 25I-NBOH (2%) and trimethoxyamphetamine (2%). The latter three have not previously been reported in municipal wastewater samples. The workflow employed allowed the prioritisation of features to be further investigated, reducing processing time and gaining in confidence in their identification.

Quantification of new psychoactive substances in Australian wastewater utilising direct injection liquid chromatography coupled to tandem mass spectrometry.

The dynamic new psychoactive substances (NPS) market presents a great challenge for public health officers, law enforcement and analytical and forensic chemists. Wastewater analysis is a complementary tool in the ongoing surveillance of these compounds but the low doses, somewhat unknown metabolism and the different chemical classes have made analytical methods difficult to develop. The current study presents a direct injection method for the quantification of 32 NPS. These include a range of classes: phenethylamines (25C-NBOMe and 4-fluoroamphetamine), synthetic cathinones (3-methylmethcathinone, butylone, dibutylone, eutylone, methcathinone, N-ethylheptedrone, N-ethylhexedrone, N-ethylpentylone and pentylone), synthetic cannabinoid receptor agonists (5F-EMB-PICA, 5F-MDMB-PICA, 5F-MDMB-PINACA, AMB FUBINACA, MDMB-4en-PINACA, cumyl pegaclone and cumyl-5F-pegaclone), opioids (2-methyl AP-237, AP-238, brorphine, isotonitazene, metonitazene and protonitazene), benzodiazepines (clonazolam, etizolam, flualprazolam and flubromazolam), plant-based NPS (7-hydroxymitragynine and mitragynine) and dissociatives (2F-deschloroketamine, 2-oxo-PCE). The method was validated in terms of linearity, range, precision (interday and intraday), limit of detection and limit of quantification, while filtration losses and matrix effects were also examined. The method was applied to wastewater samples collected from New South Wales and Queensland over the 2021-22 New Year period, when recreational drug use was expected to increase. Three NPS were found: eutylone, clonazolam and etizolam, with eutylone having the highest mass loads.