Identification of cocaine and its metabolites in urban wastewater and comparison with the human excretion profile in urine

In-sample stability and postsampling analysis of 21 illicit drugs, their metabolites and cotinine in wastewater

A thorough understanding of the degradation of chemical biomarkers in wastewater after the sampling is critical in the surveillance of illicit drug use based on the back-calculation technique. Herein, three temperatures, eight groups of matrices, and acidification were applied to simulate the preservation condition of 21 illicit drugs, their metabolites, and cotinine for a 240-day stability study. It was proved that the temperature, matrices, and acidification play vital roles in their stability in wastewater. Most of them demonstrated high stability (transformation rates < 20%) during room temperature for 45 days, and the transformation rates decreased while the storage temperature reduced. The stability of the target compounds such as cocaine (COC), 6-monoacetylmorphine (6-MAM), and amphetamine (AM) is influenced by matrices. Acidification prevented the majority of analytes from transforming, making it a feasible solution for preservation after sampling. A model that combined the effects of temperature and matrix was developed to back-calculate the concentration of target compounds during the postsampling process. The feasibility of this model was validated by correcting the loss of COC and 6-MAM from 24.2% and 16.2% to 2.98% and 2.77%. This study simulated a typical large-scale sampling and storage scenario. The effect of the temperature, pH, and matrix on in-sample stability and the postsampling analysis of selected target compounds was investigated for the first time in this study.

Using wastewater-based epidemiology to evaluate the relative scale of use of opioids

Wastewater analysis (WWA) has been used as a tool to monitor population drug use, both pharmaceutical and illicit, for over 15 years. Policymakers, law enforcement and treatment services may use WWA-derived data to seek an objective understanding of the extent of drug use in specific areas. Therefore, wastewater data should best be reported in a meaningful form to allow those that are not experts in the field to compare the scale within and between drug classes. Excreted drug loads quantified in wastewater describe the mass of drug present in the sewer. Normalisation for wastewater flow and population is standard practice and critical for comparing drug loads between different catchments and indicates a transition to an epidemiological approach (wastewater-based epidemiology (WBE)). A further consideration is necessary to accurately compare the measured level of one drug to another. The standard dose of a drug taken to elicit a therapeutic effect will vary, with some compounds requiring microgram amounts, while others are administered in the gram range. When WBE data is expressed with units representing excreted or consumed loads without considering dose amounts, the scale of drug use when comparing multiple compounds becomes distorted. To demonstrate the utility and significance of including known excretion rates, potency and typical dose amounts into back-calculations of the measured drug load, this paper compares the levels of 5 prescribed (codeine, morphine, oxycodone, fentanyl and methadone) and 1 illicit (heroin) opioid from South Australian wastewater. The data is presented at each stage of the back-calculation starting with the total mass load measured, to consumed amounts factoring in excretion rates and finally the number of doses the load equates to. This is the first paper to describe the levels of 6 opioids measured in wastewater over a 4-year period in South Australia that demonstrate the relative scale of use.

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.

Potential transmission of SARS-CoV-2 through microplastics in sewage: A wastewater-based epidemiological review

In light of the current COVID-19 pandemic caused by the virus SARS-CoV-2, there is an urgent need to identify and investigate the various pathways of transmission. In addition to contact and aerosol transmission of the virus, this review investigated the possibility of its transmission via microplastics found in sewage. Wastewater-based epidemiological studies on the virus have confirmed its presence and persistence in both influent sewage as well as treated ones. The hypothesis behind the study is that the huge amount of microplastics, especially Polyvinyl Chloride and Polyethylene particles released into the open waters from sewage can become a good substrate and vector for microbes, especially Polyvinyl Chloride and Polyethylene particles, imparting stability to microbes and aiding the "plastisphere" formation. A bibliometric analysis highlights the negligence of research toward plastispheres and their presence in sewage. The ubiquity of microplastics and their release along with the virus into the open waters increases the risk of viral plastispheres. These plastispheres may be ingested by aquatic organisms facilitating reverse zoonosis and the commercial organisms already reported with accumulating microplastics through the food chain poses a risk to human populations as well. Reliance of high population density areas on open waters served by untreated sewage in economically less developed countries might bring back viral transmission.

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Evaluation of eight psychoactive drugs used in Chinese cities by wastewater-based epidemiology

With rapid economic development, an increasing number of people suffer from mental health diseases, which are gradually receiving the attention of society. However, basic data from surveys of mental disorders are limited. Composite influent samples were collected from 26 wastewater treatment plants in 23 major cities in China. The concentrations of the psychoactive drugs diphenhydramine, fluoxetine, doxepin, imipramine, sulpiride, zolpidem, carbamazepine, and flunitrazepam in the wastewater were determined. The detection frequency of diphenhydramine, sulpiride, and carbamazepine was close to 100 %, whereas that of the compounds was lower than 35 %. Carbamazepine had the highest mean consumption (31.1 mg/d/1000 people), followed by diphenhydramine (10.4 mg/d/1000 people) and sulpiride (11.3 mg/d/1000 people). Wastewater-based epidemiology (WBE) estimates of the average use of the three drugs were lower than those from the drug statistics data. Consumption of diphenhydramine in northern China was higher than that in southern China. A correlation analysis of psychotropic and illicit drugs revealed a correlation between sulpiride and heroin use, which may be related to the adverse effects of sulpiride treatment after heroin withdrawal. Psychotropic drug use is associated with both economic and social factors. We found associations between the use of the three drugs and age, occupation, and obesity, which are risk factors for mental disorders. The results showed that the monitoring of psychotropic drug using WBE has a certain reference value for public health care and for improving the understanding of mental disorders.

Spatial and temporal assessment of crack cocaine use in 13 European cities through wastewater-based epidemiology

Already in early 2000s, concerns have been growing in the EU about increasing use of cocaine and it is estimated that below 1 % of the population administer the drug by smoking crack cocaine. New available data suggests an increase in the use of crack cocaine and an increase in the number of crack cocaine users entering treatment has been reported in several European countries. Robust estimations of crack cocaine use are however not available yet. The use of crack cocaine has long been associated with severe adverse socio-economic conditions as well as mental health problems, such as suicide ideation and depression. The aim of this study was to assess spatial trends in population-normalized mass loads of crack cocaine biomarkers (i.e., anhydroecgonine and anhydroecgonine methyl ester) in 13 European cities in six countries (the Netherlands, Belgium, Ireland, Portugal, Spain and Italy). Furthermore, temporal trends over a five-year period were evaluated through the analysis of historic samples collected in the Netherlands. Finally, the stability of the crack cocaine biomarkers in wastewater was investigated through batch experiments. The samples were analyzed with a new developed and validated hydrophilic interaction liquid chromatography coupled to mass spectrometry method. Targeted crack cocaine biomarkers were found in all cities. Also, crack cocaine biomarker was detected in wastewater from 2017 to 2021 in the Netherlands, but no significance between the years were found. With respect to biomarker in-sample stability, AEME was found to be stable in wastewater. This study assessed crack cocaine use for the first time on a broad scale, both temporal and in cities across Europe, with wastewater-based epidemiology and it shows the importance of wastewater analysis to monitor community loads of crack cocaine use.

Unraveling the dynamics of organic micropollutants in wastewater: Online LC-MS/MS analysis at high temporal resolution

Online monitoring of organic micropollutants (OMPs) in the aquatic environment at high temporal resolution is an upcoming technique that provides insights into their dynamics and has the potential to bring water research and management to a new level. An online monitoring setup was developed to quantify OMPs in wastewater treatment plant (WWTP) influent and effluent using automated and continuous sampling, sample preparation, online solid-phase extraction-liquid chromatography-tandem mass spectrometry analysis and data evaluation. This online monitoring setup provided high selectivity and sensitivity (limit of quantification down to 1 ng/L) as well as a stable performance during one week of constant operation whilst using a high sampling frequency of 10 min (>1000 samples). Custom automated data evaluation enabled quantification within seconds after each measurement and results were comparable to those from a commercial software. Additionally, an alarm tool was included in the evaluation application, which automatically notified the user in case a substance exceeded a predefined threshold. The online monitoring setup was applied to WWTP influent and effluent, where 57 substances were monitored over a period of one week and two days, respectively. High temporal resolution enabled the observation of periodic patterns of pharmaceuticals as well as pollution by OMPs originating from point and diffuse sources, while dynamics of OMPs in WWTP effluent were less pronounced. These new insights into the dynamics of OMPs in WWTP influent, which would not be observable using 24 h composite samples, will be a starting point for new stormwater and wastewater research and management strategies.

Assessing population-level stress through glucocorticoid hormone monitoring in wastewater

Stress is oftentimes overlooked in societies, despite its life-threatening impact. Here, we assessed the feasibility of measuring endogenous stress hormones to estimate population-level stress by wastewater-based epidemiology (WBE). Two primary glucocorticoids, cortisol and cortisone, were monitored in wastewater by liquid chromatography tandem mass spectrometry (LC-MS/MS), to assess changes in these physiological markers of stress in a student population (n = 26,000 ± 7100) on a university campus in the southwestern U.S. Daily composite samples were collected for seven consecutive days each month during the Fall (Autumn) 2017 and Spring 2018 academic semesters (n = 134). Reproducible weekly patterns were seen in stress hormone excretion, with the highest levels occurring on Mondays (124 ± 44 μg d^-1 per person) and Tuesdays (127 ± 54 μg d^-1 per person) and the lowest on Sundays (87 ± 32 μg d^-1 per person). Stress levels on weekdays (defined by class schedules Monday-Thursday) were significantly higher than on weekends (p < 0.05). During both Fall and Spring semesters, per person stress levels of these hormones were significantly higher (p < 0.05) during the first two months of each semester, 162 ± 28 μg d^-1 per person (August), 104 ± 29 μg d^-1 per person (September), 180 ± 14 μg d^-1 per person (January), and 114 ± 54 μg d^-1 per person (February) than in the remaining measured weeks in the semester, including finals week captured in both semesters. Overall Spring semester stress levels (113 ± 45 μg d^-1 per person) were significantly higher than the Fall (94 ± 42 μg d^-1 per person), p < 0.01. This study is the first to demonstrate the utility of endogenous biomarkers, specifically glucocorticoid hormones, to monitor population health status (in this instance community stress) in near real-time by wastewater assessments.

Aquatic Pollution and Risks to Biodiversity: The Example of Cocaine Effects on the Ovaries of Anguilla anguilla

Pollution is one of the main causes of the loss of biodiversity, currently one of the most important environmental problems. Important sources of aquatic pollution are illicit drugs, whose presence in waters is closely related to human consumption; their psychoactive properties and biological activity suggest potential adverse effects on non-target organisms, such as aquatic biota. In this study, we evaluated the effect of an environmentally relevant concentration of cocaine (20 ng L−1), an illicit drug widely found in surface waters, on the ovaries of Anguilla anguilla, a species critically endangered and able to accumulate cocaine in its tissues following chronic exposure. The following parameters were evaluated: (1) the morphology of the ovaries; (2) the presence and distribution of enzymes involved in oogenesis; (3) serum cortisol, FSH, and LH levels. The eels exposed to cocaine showed a smaller follicular area and a higher percentage of connective tissue than controls (p < 0.05), as well as many previtellogenic oocytes compared with controls having numerous fully vitellogenic and early vitellogenic oocytes. In addition, the presence and location of 3β-hydroxysteroid dehydrogenase, 17β-hydroxysteroid dehydrogenase, and P450 aromatase differed in the two groups. Finally, cocaine exposure decreased FSH and LH levels, while it increased cortisol levels. These findings show that even a low environmental concentration of cocaine affects the ovarian morphology and activity of A. anguilla, suggesting a potential impact on reproduction in this species.

Assessment of correlations between sildenafil use and comorbidities and lifestyle factors using wastewater-based epidemiology

Sildenafil (SIL) is widely used to treat erectile dysfunction. Information on its consumption and the factors influencing its use is limited in China. In this study, we sampled composite influent wastewater samples from 33 Chinese cities and analyzed SIL using liquid chromatography-tandem mass spectrometry. SIL consumption was estimated using wastewater-based epidemiology (WBE) and ranged from 10.6 mg/d/1000 people to 132 mg/d/1000 people, with a mean of 53 mg/d/1000 people. Prescription sales (3570 kg) accounted for 13.3% of the estimated SIL use (26842 kg) in 2018, thereby implying that SIL illicit use was greater than prescription use in China. Some regional differences were observed in SIL use, which was significantly higher in North China than South China (p < 0.05), thereby reflecting that the prevalence of SIL was affected by differences in lifestyle and socioeconomic factors. We found significant positive correlations between SIL use and consumption of allopurinol, hydrochlorothiazide, nicotine, and alcohol, thereby suggesting that the prevalence of SIL was associated with the prevalence of gout, hypertension, smoking, and drinking. Moreover, age structures, internet use, and marriage rates were positively correlated with SIL use, whereas the unemployment rate was negatively correlated with SIL use. Our study demonstrates that WBE is valuable for medical research to investigate licit and illicit drug use and to assess the underlying associations of different chemical uses.

Investigation of drugs of abuse in educational institutions using wastewater analysis

Wastewater analysis was used to investigate drug prevalence in primary and secondary schools and institutes of higher education located in urban and non-urban areas of six municipalities in Slovenia. Seven-hour composite raw wastewater samples from 44 educational institutions, including 19 primary schools (6-15 yrs.), ten secondary schools (15-19 yrs.), nine higher education institutions (19+ yrs.) and six mixed secondary and higher education institutions (15+ yrs.), were collected at the end of the 2018/2019 academic year. Metabolic residues of licit drugs (nicotine and alcohol), medications of abuse (morphine, codeine and methadone) and illicit drugs (cannabis, cocaine, amphetamine, methamphetamine, ecstasy and heroin) were targeted in the study. The analysis was carried out using solid-phase extraction and direct injection combined ultra-performance liquid chromatography-tandem mass spectrometry (UPLC-MS/MS). Biomarkers of nicotine, alcohol and cannabis intake were the most frequently detected, indicating a high prevalence of these drugs. Morphine and codeine were also detected, while among the stimulants, benzoylecgonine had the highest detection frequency. Drug differences were found between different levels of educational institution, geographic location (inter-municipality comparison) and degree of urbanization. However, t-distributed stochastic neighbour embedding (t-SNE) revealed that the level of educational institution was the main factor influencing the differences in drug prevalence. Although a good agreement between data from this study and other studies implementing wastewater analysis was observed, there was a discrepancy with Slovenian epidemiological survey data. Finally, despite certain drawbacks of the method, its application to detect drug residues in educational institutions provides a non-invasive insight into drug use trends.

Computational Design and Crystal Structure of a Highly Efficient Benzoylecgonine Hydrolase

Benzoylecgonine (BZE) is the major toxic metabolite of cocaine and is responsible for the long-term cocaine-induced toxicity owing to its long residence time in humans. BZE is also the main contaminant following cocaine consumption. Here, we identified the bacterial cocaine esterase (CocE) as a BZE-metabolizing enzyme (BZEase), which can degrade BZE into biological inactive metabolites (ecgonine and benzoic acid). CocE was redesigned by a reactant-state-based enzyme design theory. An encouraging mutant denoted as BZEase2, presented a >400-fold improved catalytic efficiency against BZE compared with wild-type (WT) CocE. In vivo, a single dose of BZEase2 (1 mg kg^-1 , IV) could eliminate nearly all BZE within only two minutes, suggesting the enzyme has the potential for cocaine overdose treatment and BZE elimination in the environment by accelerating BZE clearance. The crystal structure of a designed BZEase was also determined.

Systematic Evaluation of the In-Sample Stability of Selected Pharmaceuticals, Illicit Drugs, and Their Metabolites in Wastewater

The in-sample stability of selected pharmaceuticals, illicit drugs, and their metabolites in wastewater was assessed under six different conditions-untreated, addition of hydrochloric acid or sodium metabisulfite solution, combined with or without sterile filtration, and at four representative temperatures, at 35 °C for up to 28 days, 22 °C for 56 days, and 4 °C and -20 °C for 196 days, or freeze/thaw cycles for 24 weeks. Paracetamol, 6-monoacetylmorphine, morphine, and cocaine were poorly stable in untreated wastewater-e.g., with 50% transformation within 1.2-8.1 days at 22 °C, and acidification reduced their in-sample transformations. Acesulfame, carbamazepine, cotinine, methamphetamine, 3,4-methylenedioxy-methamphetamine (MDMA), ketamine, norfentanyl, 3,4-methylenedioxy-N-ethylamphetamine (MDEA), and norbuprenorphine were highly or moderately stable over the observed period, even in untreated wastewater. Fitting of pseudo-first-order kinetics and the Arrhenius equation was used to develop a multistage transformation estimation model combined with an interactive tool to evaluate possible transformation scenarios of selected biomarkers for the processes from sampling to preanalysis. However, as the wastewater composition can vary between sites and over time, the variability of in-sample stability requires further exploration.

Evaluation of Illicit Drug Consumption by Wastewater Analysis Using Polar Organic Chemical Integrative Sampler as a Monitoring Tool

Illicit drug abuse is a worldwide social and health problem, and monitoring illicit drug use is of paramount importance in the context of public policies. It is already known that relevant epidemiologic information can be obtained from the analysis of urban residual waters. This approach, named wastewater-based epidemiology (WBE), is based on the measurement of specific markers, resulting from human biotransformation of the target drugs, as indicators of the consumption of the compounds by the population served by the wastewater treatment installation under investigation. Drug consumption estimation based on WBE requires sewage sampling strategies that express the concentrations along the whole time period of time. To this end, the most common approach is the use of automatic composite samplers. However, this active sampling procedure is costly, especially for long-term studies and in limited-resources settings. An alternative, cost-effective, sampling strategy is the use of passive samplers, like the polar organic chemical integrative sampler (POCIS). POCIS sampling has already been applied to the estimation of exposure to pharmaceuticals, pesticides, and some drugs of abuse, and some studies evaluated the comparative performances of POCIS and automatic composite samplers. In this context, this manuscript aims to review the most important biomarkers of drugs of abuse consumption in wastewater, the fundamentals of POCIS sampling in WBE, the previous application of POCIS for WBE of drugs of abuse, and to discuss the advantages and disadvantages of POCIS sampling, in comparison with other strategies used in WBE. POCIS sampling is an effective strategy to obtain a representative overview of biomarker concentrations in sewage over time, with a small number of analyzed samples, increased detection limits, with lower costs than active sampling. Just a few studies applied POCIS sampling for WBE of drugs of abuse, but the available data support the use of POCIS as a valuable tool for the long-term monitoring of the consumption of certain drugs within a defined population, particularly in limited-resources settings.

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

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

A revised excretion factor for estimating ketamine consumption by wastewater-based epidemiology - Utilising wastewater and seizure data

The rate of drug excretion (excretion factor) is a critical parameter for monitoring drug consumption in the population by wastewater-based epidemiology (WBE). Previous studies have refined excretion factors for common illicit drugs, such as cocaine, amphetamine, methamphetamine, heroin, to improve the accuracy and reduce uncertainty in back-calculating consumption. Nevertheless, for ketamine, one of the most prevalent psychoactive substances, a careful review of its excretion factors has not been performed due to limited pharmacokinetic data. Here we review WBE studies and seizure data to refine and validate the excretion factors for ketamine and norketamine. The average ketamine/norketamine ratio in wastewater (5.36) was much higher than that found in urine (0.64), which means that the excretion factors derived only from pharmacokinetics data are not appropriate. Based on the comparison of the ratio between estimated consumptions of ketamine and methamphetamine by WBE with their corresponding ratio in official seizure data, a revised WBE excretion factor of 20% was proposed for ketamine following this review and applied to estimate the ketamine consumption in China. The revised estimates of ketamine consumption corresponded well with drug statistics. This suggests that the revised ketamine excretion factor is appropriate for estimating ketamine consumption by WBE. Systematic review of WBE studies is a suitable approach to refine the excretion factors for substances with inadequate pharmacokinetic data.

Materials for Solid-Phase Extraction of Organic Compounds

This review provides an overview of the most recent developments involving materials for solid-phase extraction applied to determine organic contaminants. It mainly concerns polymer-based sorbents that include high-capacity, as well as selective sorbents, inorganic-based sorbents that include those prepared using sol-gel technology along with structured porous materials based on inorganic species, and carbon nanomaterials, such as graphene and carbon nanotubes. Different types of magnetic nanoparticles coated with these materials are also reviewed. Such materials, together with their main morphological and chemical features, are described, as are some representative examples of their application as solid-phase extraction materials to extract organic compounds from different types of samples, including environmental water, biological fluids, and food.

Harmful effects of cocaine byproduct in the reproduction of sea urchin in different ocean acidification scenarios

This study has as main objective assessing the toxicity of crack-cocaine combined with different scenarios of ocean acidification on fertilization rate and embryo-larval development of Echinometra lucunter sea urchin. Effects on early life stages were assessed at five different concentrations (6,25 mg.L^-1; 12,5 mg.L^-1; 25 mg.L^-1; 50 mg.L^-1 and 100 mg.L^-1) of crack-cocaine at four different pH values (8.5; 8.0; 7.5; 7.0). The pH values were achieved using two different methodologies: adding hydrochloric acid (HCl) and injecting carbon dioxide (CO₂). The fertilization test did not show significant differences (p ≤ 0.05) compared with control sample at pH values 8.5; 8.0 and 7.5. Results of embryo-larval assays showed a half maximal effective concentration (EC50) of crack-cocaine at pH values tested (8.5, 8.0, 7.5) as 58.83, 10.67 and 11.58 mg/L^-1 for HCl acidification and 58.83, 23.28 and 12.57 mg/L^-1 for CO₂ enrichment. At pH 7.0 the effects observed in fertilization rate and embryo development were associated with the acidification. This study is the first ecotoxicological assessment of illicit drug toxicity in aquatic ecosystems at different ocean acidification scenarios.

Seasonal monitoring of cocaine and benzoylecgonine in a subtropical coastal zone (Santos Bay, Brazil)

Illicit drugs and their metabolites represent a new class of emerging contaminants. These substances are continuously discharged into wastewater which have been detected in the aquatic environment in concentrations ranging from ng.L^-1 to μg.L^-1. Our study detected the occurrence of cocaine (COC) and benzoylecgonine (BE) in a subtropical coastal zone (Santos Bay, SP, Brazil) within one year. Water samples (surface and bottom) were collected from the Santos Submarine Sewage Outfall (SSOS) area. COC and BE were measured in the samples using ultra-performance liquid chromatography coupled to tandem mass spectrometry (UPLC-ESI-MS/MS). Concentrations ranged from 12.18 to 203.6 ng.L^-1 (COC) and 8.20 to 38.59 ng.L^-1 (BE). Higher concentrations of COC were observed during the end of spring, following the population increase at summer season. COC and its metabolite occurrence in this coastal zone represent a threat to coastal organisms.

Biochemical and behavioral effects induced by cocaine exposure to Daphnia magna

Illicit drugs and their metabolites have been identified as emerging aquatic pollutants. Cocaine (COC) is one of the most used illicit drug worldwide. After human consumption, COC enters the aquatic ecosystems, where it is commonly detected in ng L^-1 concentration range. Although a number of studies have shown that the exposure to environmental concentrations of COC can induce diverse biochemical, molecular and histological effects on aquatic organisms, the information of COC-induced behavioral alterations is scant. Thus, the present study aimed at exploring both biochemical and behavioral effects induced by the exposure to two environmental concentrations (50 ng L^-1 and 500 ng L^-1) of COC on the freshwater cladoceran Daphnia magna. Specimens were exposed to selected COC concentrations for 21 days and the effects on the oxidative status, including the amount of reactive oxygen species and the activity of antioxidant (SOD, CAT and GPx) and detoxifying (GST) enzymes, and swimming activity were investigated after 7, 14 and 21 days of treatment, while effects on reproductive success was assessed after 21-days only.. Exposure to COC induced an overproduction of reactive oxygen species and a modulation of the activity of defense enzymes. Moreover, COC affected the swimming behavior and altered the reproductive success of treated specimens. Our results highlighted that environmental concentrations of COC can cause adverse effects at different levels of the biological hierarchy in a zooplanktonic species, confirming the potential threat due to this illicit drug for the aquatic community.

Profiling cocaine residues and pyrolytic products in wastewater by mixed-mode liquid chromatography-tandem mass spectrometry

This work provides a new analytical method for the determination of cocaine, its metabolites benzoylecgonine and cocaethylene, the pyrolytic products anhydroecgonine and anhydroecgonine methyl ester, and the pharmaceutical levamisole in wastewater. Samples were solid-phase extracted and extracts analyzed by liquid chromatography-tandem mass spectrometry using, for the first time in the illicit drug field, a stationary phase that combines reversed-phase and weak cation-exchange functionalities. The overall method performance was satisfactory, with limits of detection below 1 ng/L, relative standard deviations below 21%, and percentages of recovery between 93% and 121%. Analysis of 24-hour composite raw wastewater samples collected in Santiago de Compostela (Spain) and Brasilia (Brazil) highlighted benzoylecgonine as the compound showing the highest population-normalized mass loads (300-1000 mg/day/1000 inhabitants). In Brasilia, cocaine and levamisole loads underwent an upsurge on Sunday, indicating a high consumption, and likely a direct disposal, of cocaine powder on this day. Conversely, the pyrolytic product resulting from the smoke of crack, anhydroecgonine methyl ester, and its metabolite anhydroecgonine were relatively stable over the four days, agreeing with a non-recreational-associated use of crack.

Alcohol and nicotine consumption trends in three U.S. communities determined by wastewater-based epidemiology

Wastewater-based epidemiology (WBE), an emerging tool for monitoring public health in near real-time, is used extensively in Europe but applications to U.S. populations are still scarce. In this longitudinal study, raw wastewater was collected monthly from three U.S. cities as 24-h weekday composites and analyzed for evidence of alcohol and tobacco consumption. Over the 11-month sampling period, biomarkers of stimulant use were detected in wastewater by isotope dilution liquid chromatography tandem mass spectrometry in units of μg/L (ethyl sulfate, 1.6-25.1; nicotine, 0.6-26.7; cotinine, 0.2-3.8; and 3‑hydroxycotinine, 0.3-3.8). Average consumption rates in the three communities were calculated using detected biomarker levels in conjunction with wastewater flow rates, metabolic excretion factors, and population size data. Computed average per-capita consumption rates estimated for the sub-population aged 15 and above for alcohol (13.4 ± 5.6 L/y/person) and daily consumption of nicotine by smokers (14.2 ± 3.6 cigarettes/d/person) were in good agreement with U.S. survey data (9.0 L/y/person; 14.2 cigarettes/d/smoker). The WBE approach also captured impacts of temporal population influx on substance consumption patterns. This first U.S. WBE study to track recreational use of stimulants longitudinally and concurrently in multiple American cities highlights opportunities for collecting robust public health information from wastewater anonymously, economically and in near real-time.

Non-target strategies by HRMS to evaluate fluidized micro-grain activated carbon as a tertiary treatment of wastewater

Among the release solutions for reducing the discharge of organic and persistent contaminants in the aquatic environment, the use of a tertiary treatment in addition to existing conventional wastewater treatment processes is considered. The use of micro-grain activated carbon in a fluidized bed is a promising technique investigated in this study. The effluents from a large-scale pilot system were analyzed by liquid chromatography coupled with high-resolution mass spectrometry (QToF). Several strategies were deployed, namely molecular fingerprint comparison, suspected and non-target analyses, identification of refractory compounds to treatment, and finally, quantification of identified compounds. The evaluation of the molecular fingerprints provided evidence of the overall effect of the tertiary treatment on the treated wastewater quality. The suspected approach highlighted the presence of 83 pharmaceuticals and pesticides as well as transformation products in the effluents. The non-target approaches also highlighted compounds refractory to tertiary treatment, such as illicit drugs or some pharmaceuticals. The identification and quantification of identified compounds underscored the suitability of micro-grain activated carbon in eliminating many classes of pharmaceuticals with various physicochemical properties, such as anti-hypertensive, analgesic, anti-viral, antidepressant and even various pesticides.

Illicit drugs and pharmaceuticals in swimming pool waters

The occurrence of illicit drugs (cocaine, opioids, amphetamines and cannabis derivatives), some of their metabolites and 48 pharmaceuticals, was investigated in pool and source waters in ten Italian indoor swimming pools. The samples were analyzed by highperformance liquid chromatography-tandem mass spectrometry (HPLC-MS/MS), after solid phase extraction (SPE). Cocaine and its metabolites were found in nine swimming pools, at concentrations from 0.3 to 4.2 ng/L for cocaine, 1.1 to 48.7 ng/L for norcocaine, 0.7 to 21.4 ng/L for benzoylecgonine and 0.1 to 7.3 ng/L for norbenzoylecgonine. Opioids, amphetamines and cannabis derivatives were never detected. The most frequent pharmaceuticals were anti-inflammatory drugs: ibuprofen was found in all the pool waters, with a maximum 197 ng/L and ketoprofen was detected in 9/10 samples (maximum 127 ng/L). Among anticonvulsants, carbamazepine and its metabolite, 10,11-dihydro-10,11dihydroxycarbamazepine, were frequent in swimming pool water (8/10 samples) at concentrations up to 62 ng/L. The cardiovascular drug valsartan was also found frequently (8/10 samples), but at lower concentrations (up to 9 ng/L). Other pharmaceuticals were detected occasionally and at lower concentrations (atenolol, enalapril, paracetamol, hydroclorothiazide, irbesartan and dehydro-erythromycin). Carbamazepine, irbesartan and dehydroerythromycin were detected at very low levels (up to 5 ng/L) in only one of the four source water samples. A quantitative risk assessment showed that the health risk for humans to these substance in swimming pool waters was generally negligible, even for vulnerable subpopulations such as children and adolescents.

Pharmaceuticals and illicit drugs in wastewater samples in north-eastern Tunisia

Pharmaceutically active substances (PhACs) and drugs of abuse (DAs) are two classes of contaminants of emerging concern that have attracted great concern and interest by the scientific community during the last two decades. Numerous studies have revealed their presence in treated urban wastewaters. This is mainly due to the fact that some compounds are not efficiently removed during wastewater treatment processes, and are thus able to reach the aquatic environment through wastewater discharge and reuse practices. The application of an optimized multi-residue method for the simultaneous confirmation and quantification of licit and illicit drugs has been investigated in influent and effluent wastewater samples from seven wastewater treatment plants (WWTPs) located in north-eastern Tunisia. Analysis was performed through ultra-performance liquid chromatography tandem mass spectrometry (UPLC-MS/MS). Out of 12 pharmaceutical compounds analyzed, 11 of them were detected mainly in effluent wastewaters. In both matrices, antibiotics and β-blockers were the most detected groups. This suggests that these compounds show noticeable resistance against biological treatment in WWTPs. The estimated concentrations of antibiotics in effluents ranged from ca. 35 ng/L to 1.2 μg/L. However, all five studied illicit drugs were detected, mainly in influent wastewaters. Forensic investigation performed on people suspected to be drug abusers covering all Tunisian cities was conducted by monitoring an epidemiological study of human urine samples surveying rate of consumption for illicit drugs. Hence, these preliminary results confirmed the presence of illicit drugs in the influent wastewater samples. For example, quantification ranges for cocaine were found to be 25-450 ng/L in influent wastewater samples. Significant differences for cocaine consumption across the two sampling methods were observed. Consequently, we conclude that the analyses in wastewater are more reflective of the real levels of illicit drug consumption. Moreover, the cost for chromatographic analysis is lower than the screening test methods for human biological specimen, particularly staffing, which are likely to be much lower.

Wastewater-based epidemiology and enantiomeric profiling for drugs of abuse in South African wastewaters

The current study is aimed to introduce a wastewater-based epidemiology (WBE) approach for the first time on the African continent where substance abuse data is limited. The study included the quantification of several drugs of abuse (DOA) in raw wastewater samples. Quantification of urinary metabolites as drug target residues (DTR), as well as enantiomeric profiling of chiral DOA was performed to distinguish between consumption and direct disposal into sewage. Monitoring campaigns were undertaken at two South African wastewater treatment works (WWTWs) located within two provinces of the country. The presence of non-racemic 3,4-methylenedioxymethamphetamine (MDMA) and methamphetamine, as well as the metabolite of cocaine, benzoylecgonine (BEG), confirmed their consumption within the areas investigated. Enantiomeric profiling further pointed to the abuse of methamphetamine as the primary DOA with use estimates calculated between 181.9 and 1184.8mg·day^-1·1000inhabitants^-1. Population-normalised mass loads for MDMA and cocaine confirmed their status as secondary DOA within the study sites. Use estimates for the new psychoactive substance (NPS) mephedrone were performed for one WWTW. The minor metabolite of heroin, O-6-monoacetylmorphine (O-6-MAM), was also detected at one WWTW and served as a qualitative indicator for heroin abuse within the area. These findings provide a novel comparison of the WBE approach in a developing-country with other global studies, with the aim to strengthen this approach as a tool to inform drug prevention strategies in countries where substance abuse data is limited due to financial constraints and lack of government structures to facilitate conventional monitoring.

Data on occurrence and fate of emerging contaminants in a urbanised area

These data and analyses support the research article “Mass balance of emerging contaminants in the water cycle of an highly urbanized and industrialized area of Italy” by Castiglioni et al. (2018) [1].

The occurrence of 80 emerging contaminats in waste and surface water was investigated in an highly urbanised area of Italy, the River Lambro basin. The data presented here include: (1) concentrations in untreated and treated wastewater of different wastewater treatment plants (WWTPs); (2) concentrations in surface water collected along the river Lambro, in the north and south of the city of Milan (main urban center in the area). These concentrations indicate the distribution and fate of emerging contaminats in the environment.

Benzoylecgonine exposure induced oxidative stress and altered swimming behavior and reproduction in Daphnia magna

Several monitoring studies have shown that benzoylecgonine (BE) is the main illicit drug residue commonly measured in the aquatic system worldwide. Few studies have investigated the potential toxicity of this molecule towards invertebrate and vertebrate aquatic non-target organisms focusing on effects at low levels of the biological organization, but no one has assessed the consequences at higher ones. Thus, the present study was aimed at investigating the toxicity of a 48-h exposure to two concentrations of BE, similar to those found in aquatic ecosystems (0.5 μg/L and 1.0 μg/L), on the cladoceran Daphnia magna at different levels of the ecological hierarchy. We relied on a multi-level approach focusing on the effects at biochemical/biomolecular (biomarkers), individual (swimming activity) and population (reproduction) levels. We measured the amount of reactive oxygen species and of the activity of antioxidant (SOD, CAT, and GPx) and detoxifying (GST) enzymes to assess if BE exposure can alter the oxidative status of D. magna specimens, while the lipid peroxidation (TBARS) was measured as a marker of oxidative damage. Moreover, we also measured the acetylcholinesterase (AChE) activity because it is strictly related to behavioral changes in aquatic organisms. Changes in swimming behavior were investigated by a video tracking analysis, while the consequences on reproduction were assessed by a chronic toxicity test. Our results showed that BE concentrations similar to those found in aquatic ecosystems induced oxidative stress and inhibited AChE activity, affecting swimming behavior and the reproduction of Daphnia magna individuals.

Estimation of caffeine intake from analysis of caffeine metabolites in wastewater

Caffeine metabolites in wastewater were investigated as potential biomarkers for assessing caffeine intake in a population. The main human urinary metabolites of caffeine were measured in the urban wastewater of ten European cities and the metabolic profiles in wastewater were compared with the human urinary excretion profile. A good match was found for 1,7-dimethyluric acid, an exclusive caffeine metabolite, suggesting that might be a suitable biomarker in wastewater for assessing population-level caffeine consumption. A correction factor was developed considering the percentage of excretion of this metabolite in humans, according to published pharmacokinetic studies. Daily caffeine intake estimated from wastewater analysis was compared with the average daily intake calculated from the average amount of coffee consumed by country per capita. Good agreement was found in some cities but further information is needed to standardize this approach. Wastewater analysis proved useful to providing additional local information on caffeine use.

Occurrence and fate of illicit drugs and pharmaceuticals in wastewater from two wastewater treatment plants in Costa Rica

Chemical analysis of raw wastewater in order to assess the presence of biological markers entering a wastewater treatment plant can provide objective information about the health and lifestyle of the population connected to the sewer system. This work was performed in a tropical country of Central America, Costa Rica, with the aim of extending this knowledge to new world regions. This work is the first to report wastewater-based epidemiological data on the use of illicit drugs in this region of the world. Composite wastewater samples from the influents of two different wastewater treatment facilities and surface water samples from surrounding areas were collected applying the best practice protocol and analysed to investigate the occurrence and fate of selected illicit drugs of abuse and pharmaceuticals. Results showed the presence of chemical indicators of the classic drugs cocaine and cannabis at high concentration levels, besides the moderate presence of the opiates codeine and morphine. Neither the worldwide commonly used psychoactive substances of abuse such as synthetic phenethylamines, nor pharmaceuticals from the family of benzodiazepines were detected, demonstrating the spatial differences in drug use among different world regions. In addition, effluent wastewater samples were analysed and compared to influent concentrations in order to evaluate the decrease in concentration of the targeted analytes through two treatment technologies. As a final step, a wide-scope qualitative screening, including hundreds of suspect compounds, was applied in order to have a better knowledge on the presence of pharmaceuticals in waters and to assess the potential impact of the treated wastewater into the receiving aquatic ecosystems.

Bacterial isolates degrading ritalinic acid-human metabolite of neuro enhancer methylphenidate

The consumption of nootropic drugs has increased tremendously in the last decade, though the studies on their environmental fate are still scarce. Nootropics are bioactive compounds designed to alter human's physiology therefore the adverse effects towards wildlife can be expected. In order to understand their environmental impact, the knowledge on their transformation pathways is necessary. Methylphenidate belongs to the most prescribed neuro-enhancers and is among the most favored smart drugs used in non-medical situations. It is metabolized in human liver and excreted as ritalinic acid. Here, we showed for the first time that ritalinic acid can be biodegraded and used as a sole carbon and nitrogen source by various microbial strains originating from different environmental samples. Five axenic strains were isolated and identified as: Arthrobacter sp. strain MW1, MW2 and MW3, Phycicoccus sp. strain MW4 and Nocardioides sp. strain MW5. Our research provides the first insight into the metabolism of ritalinic acid and suggests that it may differ depending on the strain and growth conditions, especially on availability of nitrogen. The isolates obtained in this study can serve as model organisms in further studies on the catabolism of ritalinic acid and methylphenidate but potentially also other compounds with similar structures. Our findings have important implication for the sewage epidemiology. We demonstrated that ritalinic acid is subject to quick and efficient biodegradation thus its use as a stable biomarker should be reconsidered.

Environmental concentrations of cocaine and its main metabolites modulated antioxidant response and caused cyto-genotoxic effects in zebrafish embryo cells

Illicit drugs have been recently identified as a serious environmental problem because of the growing evidence regarding their occurrence in aquatic environment and potential toxicity towards non-target organisms. Among them, cocaine (COC) and its main metabolites, namely benzoylecgonine (BE) and ecgonine methyl ester (EME), are commonly measured in freshwaters worldwide at levels that might cause diverse sub-lethal effects to aquatic organisms. Thus, the present study was aimed at investigating the potential adverse effects induced by the exposure to environmental concentrations (0.04, 0.4, 4 and 40 nM) of COC, BE, and EME on zebrafish (Danio rerio) embryos at 96 h post fertilization. Cytotoxicity was assessed by the Trypan Blue exclusion method, while primary and fixed genetic damages were evaluated by the Single Cell Gel Electrophoresis (SCGE) assay, and the DNA diffusion assay together with the Micronucleus test, respectively. The involvement of oxidative stress in the mechanism of action (MoA) of all tested drugs was assessed by measuring the activity of defense enzymes (SOD, CAT, GPx, and GST) and the expression of their encoding genes. Exposure to COC and both metabolites significantly reduced cell viability, increased DNA fragmentation and promoted the onset of apoptotic cells and micronuclei in zebrafish embryos. Results from oxidative stress-related endpoints and gene expression suggested that the observed genotoxicity may be caused by an overproduction of free radicals that imbalanced the oxidative status of embryos. The integration of biomarker responses into a synthetic index showed that at each tested concentration, BE and EME had a similar toxicity and were both more toxic than COC. Our data confirmed the potential toxicity of environmental concentrations of COC, BE, and EME, suggesting the need of further in-depth studies to shed light on their MoA and long-term toxicity towards non-target aquatic species.

Monitoring MDMA metabolites in urban wastewater as novel biomarkers of consumption

Consumption of 3,4-methylendioxymethamphetamine (MDMA) has been always estimated by measuring the parent substance through chemical analysis of wastewater. However, this may result in an overestimation of the use if the substance is directly disposed in sinks or toilets. Using specific urinary metabolites may overcome this limitation. This study investigated for the first time the suitability of a panel of MDMA metabolites as biomarkers of consumption, considering the specific criteria recently proposed, i.e. being detectable and stable in wastewater, being excreted in a known percentage in urine, and having human excretion as the sole source. A new analytical method was developed and validated for the extraction and analysis of MDMA and three of its main metabolites in wastewater. 24-h composite raw wastewater samples from three European cities were analysed and MDMA use was back-calculated. Results from single MDMA loads, 4-hydroxy-3-methoxymethamphetamine (HMMA) loads and from the sum of MDMA, HMMA and 4-hydroxy-3-methoxyamphetamine (HMA) loads were in line with the well-known recreational use of this drug: consumption was higher during the weekend in all cities. HMMA and HMA turned out to be suitable biomarkers of consumption; however, concentrations measured in wastewater did not resemble the expected pharmacokinetic profiles, quite likely due to the very limited information available on excretion profiles. Different options were tested to back-calculate MDMA use, including the sum of MDMA and its metabolites, to balance the biases associated with each single substance. Nevertheless, additional pharmacokinetic studies are urgently needed in order to get more accurate excretion rates and, therefore, improve the estimates of MDMA use.

Occurrence of cocaine and metabolites in hospital effluent - A risk evaluation and development of a HPLC method using DLLME

A fast method for the determination of cocaine and its metabolites in hospital effluent samples was worked out by using liquid chromatography with the aid of fluorescence and diode array detection. Solid phase extraction and dispersive liquid -liquid microextraction were employed during the sample preparation stage. The experiment was conducted by using Chromabond^® C18 ec 6 ml/500 mg cartridges, with recoveries higher than 96.6%, 88.3%, 78.7%, and LOQ_m 0.15; 0.18 and 0.30 μg L^-1 for cocaine, benzoylecgonine and anhydroecgonine respectively. In the case of DLLME, different chemical conditions and solvent combinations were tested to find the best settings for the microextraction: pH 9; addition of 0.3 mol L^-1 NaCl; 150 μL extractor (chloroform) and 350 μL disperser (methanol). The recoveries for cocaine were as high as 98.3% with LOQ_m 0.3 μg L^-1. After validation, these methods were applied to quantification of the analytes. While the concentration of the anhydroecgonine, (the main pyrolytic metabolite of cocaine), remained below the limit of detection, the range of concentrations of cocaine and benzoylecgonine determined were 0.4-4.9 μg L^-1 and 0.9-8.6 μg L^-1, respectively. The occurrence has a relatively median/high environmental impact. These concentration values suggest that a role is played by other sources of cocaine, probably related to transport, or handling and the consumption of the drug. The outcome is that cocaine can be quantified by using DLLME as well as SPE, however, DLLME offered clear benefits like simplicity, affordability, and speed, as well as only requiring a small volume of solvents and samples.

Estimating population size in wastewater-based epidemiology. Valencia metropolitan area as a case study

Wastewater can provide a wealth of epidemiologic data on common drugs consumed and on health and nutritional problems based on the biomarkers excreted into community sewage systems. One of the biggest uncertainties of these studies is the estimation of the number of inhabitants served by the treatment plants. Twelve human urine biomarkers -5-hydroxyindoleacetic acid (5-HIAA), acesulfame, atenolol, caffeine, carbamazepine, codeine, cotinine, creatinine, hydrochlorothiazide (HCTZ), naproxen, salicylic acid (SA) and hydroxycotinine (OHCOT)- were determined by liquid chromatography-tandem mass spectrometry (LC-MS/MS) to estimate population size. The results reveal that populations calculated from cotinine, 5-HIAA and caffeine are commonly in agreement with those calculated by the hydrochemical parameters. Creatinine is too unstable to be applicable. HCTZ, naproxen, codeine, OHCOT and carbamazepine, under or overestimate the population compared to the hydrochemical population estimates but showed constant results through the weekdays. The consumption of cannabis, cocaine, heroin and bufotenine in Valencia was estimated for a week using different population calculations.

Measuring biomarkers in wastewater as a new source of epidemiological information: Current state and future perspectives

The information obtained from the chemical analysis of specific human excretion products (biomarkers) in urban wastewater can be used to estimate the exposure or consumption of the population under investigation to a defined substance. A proper biomarker can provide relevant information about lifestyle habits, health and wellbeing, but its selection is not an easy task as it should fulfil several specific requirements in order to be successfully employed. This paper aims to summarize the current knowledge related to the most relevant biomarkers used so far. In addition, some potential wastewater biomarkers that could be used for future applications were evaluated. For this purpose, representative chemical classes have been chosen and grouped in four main categories: (i) those that provide estimates of lifestyle factors and substance use, (ii) those used to estimate the exposure to toxicants present in the environment and food, (iii) those that have the potential to provide information about public health and illness and (iv) those used to estimate the population size. To facilitate the evaluation of the eligibility of a compound as a biomarker, information, when available, on stability in urine and wastewater and pharmacokinetic data (i.e. metabolism and urinary excretion profile) has been reviewed. Finally, several needs and recommendations for future research are proposed.

Refining correction factors for back-calculation of illicit drug use

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

Mass Spectrometry-Based Visualization of Molecules Associated with Human Habitats

The cars we drive, the homes we live in, the restaurants we visit, and the laboratories and offices we work in are all a part of the modern human habitat. Remarkably, little is known about the diversity of chemicals present in these environments and to what degree molecules from our bodies influence the built environment that surrounds us and vice versa. We therefore set out to visualize the chemical diversity of five built human habitats together with their occupants, to provide a snapshot of the various molecules to which humans are exposed on a daily basis. The molecular inventory was obtained through untargeted liquid chromatography-tandem mass spectrometry (LC-MS/MS) analysis of samples from each human habitat and from the people that occupy those habitats. Mapping MS-derived data onto 3D models of the environments showed that frequently touched surfaces, such as handles (e.g., door, bicycle), resemble the molecular fingerprint of the human skin more closely than other surfaces that are less frequently in direct contact with humans (e.g., wall, bicycle frame). Approximately 50% of the MS/MS spectra detected were shared between people and the environment. Personal care products, plasticizers, cleaning supplies, food, food additives, and even medications that were found to be a part of the human habitat. The annotations indicate that significant transfer of chemicals takes place between us and our built environment. The workflows applied here will lay the foundation for future studies of molecular distributions in medical, forensic, architectural, space exploration, and environmental applications.

Occurrence of illicit drugs and selected pharmaceuticals in Slovak municipal wastewater

We analyzed illicit drugs and their metabolites and pharmaceuticals in wastewater from 15 selected wastewater treatment plants (WWTPs) in Slovakia. Our results indicate that methamphetamine is one of the most commonly used illegal drugs in all the regions of Slovakia monitored in this study. Compared with the international results, the Slovak cities of Dunajská Streda (479 mg/day/1000inh) and Trnava (354 mg/day/1000inh) are among the cities with the largest numbers of methamphetamine users in Europe. These results indicate an increase in the incidence of drugs in big cities and in the satellite cities (Trnava and Dunajská Streda) near Bratislava. These results also confirm the police statistics about production and use of illicit drugs in Slovakia. The highest specific loads of cocaine were found in Bratislava (112 mg/day/1000inh), followed by Petržalka (74 mg/day/1000inh). Compared with other European cities, Bratislava and the other Slovak cities in this study have a relatively low number of COC consumers. The ecstasy load in wastewater from larger cities also significantly increased over the weekend and during music festivals. The highest 2-year mean concentrations of THC-COOH, a cannabis biomarker, were observed in the sewage from BA-Petržalka and BA-Central (191 and 171 ng/L, respectively). A first complex monitoring of pharmaceuticals in all therapeutic groups was also realized in selected Slovak WWTPs. Occurrence of wide spectrum of pharmaceuticals with very high concentrations as well as consumptions were observed mainly in small Slovak cities. Considering all 120 monitored pharmaceuticals, Valsartan had the highest concentrations: 6000 ng/L, on average.

Photostability of 6-MAM and morphine exposed to controlled UV irradiation in water and methanol solution: HRMS for the characterization of transformation products and comparison with the dry state

The UVA and UVB light-induced behaviour of 6-monoacetylmorphine (6-MAM) and morphine, the main metabolites of heroin, was studied in methanol, aqueous solution and in the dry state. UVA and UVB irradiations were performed for different times (radiant energies of 20-300J/cm(2)). UV spectra of irradiated samples were compared with samples kept in the dark. To estimate the extent of photolysis, positive ion electrospray ionization experiments were performed on the irradiated samples by LC-HRMS. Tentative identification of photoproducts was performed on the basis of their elemental formula as calculated by HRMS results. Morphine and 6-MAM demonstrated to be quite stable under UVA light but very sensitive to UVB irradiation. In methanol solutions they undergo a similar pattern, both reaching 90% photodegradation after 100J/cm(2) of UVB, with a slightly faster kinetic for morphine at lower doses. In water, the yields of photodegradation are nearly one third lower than in methanol. In the solid state, the yield of photodegradation is lower than in solution. The structures of some UVB-induced degradation products are proposed. Photoaddition of the solvent and photooxidation seem the main pathways of phototransformation of these molecules. Moreover, both compounds revealed to generate singlet oxygen under UVB exposure.

Investigation on the removal of the major cocaine metabolite (benzoylecgonine) in water matrices by UV254/H2O2 process by using a flow microcapillary film array photoreactor as an efficient experimental tool

A microcapillary film reactor (MCF) was adopted to evaluate and compare the removal efficiency of benzoylecgonine (BE), an emerging micropollutant deriving from illicit drug abuse (cocaine), in different aqueous matrices: milliQ water, synthetic and real wastewater and surface water. The removal processes investigated were the direct photolysis with UV radiation at 254 nm, and the advanced oxidation process (AOP) with the same UV radiation and hydrogen peroxide. As a result of the microfluidics approach developed through an innovative experimental apparatus, full conversion of BE was reached within a few seconds or minutes of residence time in the MCF depending on the process conditions adopted. The radiation dose was estimated to be approximately 5.5 J cm(-2). The innovative MCF reactor was found to be an effective tool for photochemical studies, especially when using highly priced, uncommon, or regulated substances. The removal efficiency was affected by the nature of the aqueous matrix, due to the presence of different xenobiotics and natural compounds that act primarily as HO(•) radical scavengers and secondly as inner UV254 filters. Moreover, nano-liquid chromatography (LC)-high resolution-mass spectrometry analysis was utilized to identify the main reaction transformation products, showing the formation of hydroxylated aromatics during the photochemical treatment.