Advances in the analysis of legal and illegal drugs in the aquatic environment

Optimization and validation of an extraction method for the analysis of multi-class emerging contaminants in soil and sediment

Analytical methods for the determination of multi-class emerging contaminants are limited for soil and sediment while they are essential to provide a more complete picture of their distribution in the environment and to understand their fate in different environmental compartments. In this paper, we present the development and optimization of an analytical strategy that combines reliable extraction, purification and the analysis using ultra-pressure liquid chromatography triple quadrupole mass spectrometry (UPLC-MS/MS) of 90 emerging organic contaminants including pesticides, pharmaceuticals and personal care products, flame retardants, per- and polyfluoroalkyl substances (PFASs) and plasticizers in soil and sediment. To extract a wide range of chemicals, the extraction strategy is based on the QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) approach. A number of different options were investigated (buffer, acidification, addition of EDTA, different types and combinations of dispersive SPE etc.) and the effectiveness of the chemical extraction procedure and the clean-up was assessed for two matrices: soil (organic matter content of 9%) and sediment (organic matter content of 1.9%). The method was fully validated for both matrices, in terms of accuracy, linearity, repeatability (intra-day), reproducibility (inter-day), method limits of detection and quantification (LODs and MLOQs, respectively). The final performance showed good accuracy and precision (mean recoveries were between 70 and 120% with relative standard deviations (RSD) less than 20% in most cases), low matrix effects, good linearity for the matrix-matched calibration curve (R2≥0.991) and MLOQs ranged from 0.25 and 10 µg/kg. To demonstrate the applicability and suitability of the validated method, soil and sediment samples from Vietnam, France, Sweden and Mexico were analyzed. The results showed that of the 90 target compounds, a total of 33 were quantified in the sediment and soil samples analyzed. In addition to multi-target analysis, this strategy could be suitable for non-target screening, to provide a more comprehensive view of the contaminants present in the samples.

Reply to Mehrotra et al. Wastewater-Based Surveillance Does Not Belong in a Regulatory Framework Designed to Protect Waters That Receive Treated Wastewater. Comment on "Wright, T.; Adhikari, A. Utilizing a National Wastewater Monitoring Program to Address the U.S. Opioid Epidemic: A Focus on Metro Atlanta, Georgia. Int. J. Environ. Res. Public Health 2023, 20, 5282"

We are honored that authors are reading our manuscript [...].

Monitoring and ecological risk of illegal drugs before and after sewage treatment in an area

In this study, the occurrence of illicit drugs and their metabolites in the sewerage systems and in the influent and effluent of wastewater treatment plant (WWTP) in Konya, Turkey, was presented. The drug removal efficiencies of the central WWTP were investigated. Potential ecotoxicological risks for algae, fish, and Daphnia magna in the receiving environments were also evaluated. The highest estimated mean illicit drug use was obtained for cannabis (marijuana) at 280 ± 12 mg/day/1000 inhabitants and 430 ± 20 g/day/1000 inhabitants (15-64 years). Amphetamine was found to be the second most consumed drug of abuse. While cannabis and ecstasy consumption values were higher during the weekend, cocaine use dominated on weekdays. The removal efficiencies for THC-COOH and THC-OH were 100% in the WWTP. The average removal of cocaine, amphetamine, methamphetamine, MDMA, MDA, and methadone varied between 46 ± 7 and 87 ± 3%. The maximum concentration level of MDMA found can pose some low risk for Daphnia magna. The rest of the compounds detected in effluents did not show any toxic effects on fish, Daphnia magna, or algae. However, when the cumulative estimated risk quotient values were evaluated, there might be a low risk for Daphnia magna and algae in the receiving environment.

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.

A Validated Method for the Simultaneous Determination of Methamphetamine and 3,4-Methylenedioxy-N-methamphetamine in Blood-Based Liquid Chromatography-Tandem Mass Spectrometry

A liquid chromatography-tandem mass spectrometry (HPLC-MS/MS) method has been validated for the simultaneous determination of methamphetamine (MA) and 3,4-methylenedioxy-N-methamphetamine (MDMA) in the blood sample. Under the optimal experimental conditions, the concentration of MA can be determined in the range from 1 µg/L to 5000 µg/L with the method detection limit (MDL) of 0.31 µg/L. The range from 0.5 to 500 µg/L is observed for the determination of MDMA with the MDL down to 0.25 µg/L. The practical applicability of the method is performed with the recovery ranging from 85.3% to 94% for MA and from 86.9% to 95.5% for MDMA. At the different concentrations of drugs, the relative standard deviations (RSD) for both MA and MDMA are lower than 5.7%. The method was applied to analyse 1995 blood samples that had been collected from the Forensic Medicine Centre of Ho Chi Minh City. The results showed 1.75% positive with MA and 0.25% positive with MDMA. These two drugs take 10% of the total drugs positive samples. By using deuterium-labelled methamphetamine-d5 and 3,4-methylenedioxy-N-methamphetamine-d5 as the internal standards in the determination and the use of MS/MS in multiple reaction monitoring mode signal readout, the method exhibits robustness specificity and can be applied in simultaneous determination of MA and MDMA in blood with high selectivity and sensitivity.

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.

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.

Transformation of norfloxacin during the chlorination of marine culture water in the presence of iodide ions

The antibacterial agent norfloxacin (NOR) and sodium hypochlorite (NaClO), which are both widely used in marine culture, react with each other to form the halogenated disinfection byproducts (X-DBPs). The effects of the water characteristics and iodide concentration on the reaction kinetics were investigated. The results showed that the reaction rate of NOR with NaClO increases from 0.0586 min^-1 to 0.1075 min^-1 when the iodide concentration was changed from 0 μg^-1 to 50 μg^-1. This demonstrated the enhancement of NOR oxidation in the presence of iodide ions. Four novel iodinated DBPs (I-DBPs) were identified in the marine culture water. Iodine substitutions occurred at the C3 and C8 positions of NOR. The formation mechanisms of X-DBPs in the marine culture water were proposed based on the intermediate and final products. NOR may undergo a ring-opening reaction, a de-carbonyl reaction and substitution to form intermediates and finally generate the X-DBPs. Furthermore, the predicted logK_OW and logBCF values of the I-DBPs were higher than that of the Br-DBPs and Cl-DBPs. The AOX concentration in the synthetic water samples decreased in the following order: seawater (8.49 mg L^-1) > marine culture water (4.05 mg L^-1) > fresh water (1.89 mg L^-1). The amount of AOX also increased with the increase in iodide concentration. These results indicated that the I-DBPs were more toxic than their brominated and chlorinated analogues.

Host-Guest Recognition of Pesticides by Calixarenes

This article is based on a review of the literature and our own experience with toxicological molecules. We explain the nature of calix[n]arenes and as their recognized properties are used to detect compounds of toxicological interest, mainly the most important pesticide families such as organophosphorated, organochlorine compounds, pyrethroid insecticides, carbamate fungicides, and herbicides, using different techniques. In addition, we show the role of the macrocycle and its interactions, and the advantage of using this type of compound for improving conventional techniques, where the phenomenon of recognition is very important, such as chromatography, solid-phased extraction, and the development of specific sensors, among others and Even we also show the use of this macrocycle for detoxication procedures in vivo. In this way, we display as the multiple possibilities of functionalization of the calix[n]arenes makes these versatile molecules in the phenomena of specific recognition. Finally, This review highlights the main analytical methods reported in the literature for determination of plaguicides by host-guest interaction with calixarenes. In this way, among the available analytical tools, chromatographic, and electrochemical-based methods are the most used techniques for the detection and to quantify plaguicides using calixarenes.

Sample as solid support in MSPD: A new possibility for determination of pharmaceuticals, personal care and degradation products in sewage sludge

A method based on matrix-solid phase dispersion (MSPD), focused on the principles of green analytical chemistry, aimed at the use of alternative solid supports and less toxic solvents, was developed for the simultaneous determination of 19 pharmaceuticals, 4 personal care products (PPCPs) and 4 degradation products in sewage sludge samples. Higher recoveries were achieved when 2 g sample was macerated for 5 min in a glass mortar, transferred to a centrifuge tube, and 1 min vortex agitation with 5 mL methanol. The performance of the method was evaluated through linearity, recovery, precision (intra-day), method detection and quantification limits (MDL and MQL) and matrix effect. The calibration curves prepared in methanol and in the matrix extract showed a correlation coefficient ranging from 0.98 to 0.99. MQL values ranged from 1.25 to 1250 ng g^-1. Recoveries between 50 and 120% were reached with RSDs lower than 20% for most compounds. The method presented low and medium matrix effects for most analytes. This method was successfully applied to real samples and of the 27 compounds determined, amitriptyline, carbamazepine, diclofenac, haloperidol, ketoconazole, miconazole, albendazole, mebendazole, thiabendazole, triclosan and triclocarban were detected in concentrations between 2.5 and 5400 ng g^-1.

Marine environment pollution: The contribution of mass spectrometry to the study of seawater

The study of marine pollution has been traditionally addressed to persistent chemicals, generally known as priority pollutants; a current trend in environmental analysis is a shift toward "emerging pollutants," defined as newly identified or previously unrecognized contaminants. The present review is focused on the peculiar contribution of mass spectrometry (MS) to the study of pollutants in the seawater compartment. The work is organized in five paragraphs where the most relevant groups of pollutants, both "classical" and "emerging," are presented and discussed, highlighting the relative data obtained by the means of different MS techniques. The hyphenation of MS and separative techniques, together with the development of different ion sources, makes MS and tandem MS the analytical tool of choice for the determination of trace organic contaminants in seawater. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 37:492-512, 2018.

Mass spectrometric strategies for the investigation of biomarkers of illicit drug use in wastewater

The analysis of illicit drugs in urban wastewater is the basis of wastewater-based epidemiology (WBE), and has received much scientific attention because the concentrations measured can be used as a new non-intrusive tool to provide evidence-based and real-time estimates of community-wide drug consumption. Moreover, WBE allows monitoring patterns and spatial and temporal trends of drug use. Although information and expertise from other disciplines is required to refine and effectively apply WBE, analytical chemistry is the fundamental driver in this field. The use of advanced analytical techniques, commonly based on combined chromatography-mass spectrometry, is mandatory because the very low analyte concentration and the complexity of samples (raw wastewater) make quantification and identification/confirmation of illicit drug biomarkers (IDBs) troublesome. We review the most-recent literature available (mostly from the last 5 years) on the determination of IDBs in wastewater with particular emphasis on the different analytical strategies applied. The predominance of liquid chromatography coupled to tandem mass spectrometry to quantify target IDBs and the essence to produce reliable and comparable results is illustrated. Accordingly, the importance to perform inter-laboratory exercises and the need to analyze appropriate quality controls in each sample sequence is highlighted. Other crucial steps in WBE, such as sample collection and sample pre-treatment, are briefly and carefully discussed. The article further focuses on the potential of high-resolution mass spectrometry. Different approaches for target and non-target analysis are discussed, and the interest to perform experiments under laboratory-controlled conditions, as a complementary tool to investigate related compounds (e.g., minor metabolites and/or transformation products in wastewater) is treated. The article ends up with the trends and future perspectives in this field from the authors' point of view. © 2016 Wiley Periodicals, Inc. Mass Spec Rev 37:258-280, 2018.

The influence of antibiotics on wastewater treatment processes and the development of antibiotic-resistant bacteria

The influence of antibiotics, namely doxycycline, gentamicin, penicillin, nitrofurantoin, and rifampicin, on wastewater treatment was assessed. The presence of 100-300 μg/L of antibiotics (63.52-134.41 mg/g.d.w·d) marginally influenced organic matter degradation, without impacting nitrogen or phosphorus concentrations. However, a significant increase in the number of antibiotic-resistant bacteria was observed, which varied with different antibiotics. The largest number of bacteria became resistant to nitrofurantoin and penicillin. After the process, some multi-resistant strains were isolated from the sludge. Two of them revealed the activity of carbapenamase, the enzyme directly related to resistance against β-lactam antibiotics.

Development of an online SPE-UHPLC-MS/MS method for the multiresidue analysis of the 17 compounds from the EU "Watch list"

During the last decades, the quality of aquatic ecosystems has been threatened by increasing levels of pollutions, caused by the discharge of man-made chemicals, both via accidental release of pollutants as well as a consequence of the constant outflow of inadequately treated wastewater effluents. For this reason, the European Union is updating its legislations with the aim of limiting the release of emerging contaminants. The Commission Implementing Decision (EU) 2015/495 published in March 2015 drafts a "Watch list" of compounds to be monitored Europe-wide. In this study, a methodology based on online solid-phase extraction (SPE) ultra-high-performance liquid chromatography coupled to a triple-quadrupole mass spectrometer (UHPLC-MS/MS) was developed for the simultaneous determination of the 17 compounds listed therein. The proposed method offers advantages over already available methods, such as versatility (all 17 compounds can be analyzed simultaneously), shorter time required for analysis, robustness, and sensitivity. The employment of online sample preparation minimized sample manipulation and reduced dramatically the sample volume needed and time required, dramatically the sample volume needed and time required, thus making the analysis fast and reliable. The method was successfully validated in surface water and influent and effluent wastewater. Limits of detection ranged from sub- to low-nanogram per liter levels, in compliance with the EU limits, with the only exception of EE2. Graphical abstract Schematic of the workflow for the analysis of the Watch list compounds.

Insights into the uptake, metabolization, and translocation of four non-steroidal anti-inflammatory drugs in cress (Lepidium sativum) by HPLC-MS2

The metabolization of four non-steroidal anti-inflammatory drugs by cress (Lepidium sativum) was investigated using a HPLC-MS² method. Cress was grown hydroponically in water containing 0.1 mg/L of each drug for investigations on the kinetics of drug uptake and metabolization over a growing period of 12 days. It could be shown that the parent drugs are metabolized and the abundance of both the parent drug and the metabolites formed, varies over time. Furthermore the distribution of the investigated substances within the different plant parts changed throughout the duration of the experiment due to translocation. Finally cress was cultivated in a solution containing the four drugs in concentrations as low as 0.001 mg/L to resemble the situation in real reclaimed wastewaters. Employing a QuEChERS approach for sample extraction and HPLC-MS² in the multiple reaction monitoring mode allowed detecting nine metabolites in this cress sample.

Determination of fluoroquinolones in fish tissues, biological fluids, and environmental waters by liquid chromatography tandem mass spectrometry

This work describes the optimization, validation, and application in real samples of accurate and precise analytical methods to determine ten fluoroquinolones (FQs) (norfloxacin, enoxacin, pefloxacin, ofloxacin, levofloxacin, ciprofloxacin, danofloxacin, lomefloxacin, enrofloxacin, and sparfloxacin) in different environmental matrices, such as water (estuarine, seawater, and wastewater treatment plant effluent), fish tissues (muscle and liver), and fish biofluids (plasma and bile). The analysis step performed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) was fully optimized to improve the separation and detection steps. The extraction of analytes from fish tissues was accomplished using focused ultrasound solid-liquid extraction using methanol/acetic acid (95:5 v/v) as extractant. The preconcentration and clean-up steps were optimized in terms of extraction efficiency and cleanliness and the best strategy for each matrix was selected: (i) Oasis HLB for seawater and muscle, (ii) liquid-liquid extraction combined with Oasis HLB for the lipid-rich liver, (iii) the combination of Evolute-WAX and Oasis HLB for estuarine water and wastewater treatment plant effluent, and (iv) molecular imprinted polymers for biofluids. The methods afforded satisfactory apparent recoveries (80-126%) and repeatability (RSD < 15%), except for sparfloxacin, which showed a lack of correction with the available isotopically labeled surrogates ([²H₈]-ciprofloxacin and [²H₅]-enrofloxacin). Ciprofloxacin, norfloxacin, and ofloxacin were detected in both water and fish liver samples from the Biscay Coast at concentrations up to 278 ng/L and 4 ng/g, respectively. To the best of our knowledge, this work is one of the few analyzing up to ten FQs and in so many fish tissues and biofluids. Graphical abstract Determination of fluoroquinolones in different environmental matrices, such as water (estuarine, seawater, and wastewater treatment plant effluent), fish tissues (muscle and liver), and fish biofluids (plasma and bile).

Determination of carbamazepine and 12 degradation products in various compartments of an outdoor aquatic mesocosm by reliable analytical methods based on liquid chromatography-tandem mass spectrometry

The aims of this work are to develop suitable analytical methods to determine the widely used anticonvulsant carbamazepine and 12 of its degradation/transformation products in water, sediment, fish (Gasterosteus aculeatus) and mollusc (Dreissena polymorpha). Protocols based on solid phase extraction for water, pressurized-liquid extraction for sediments and QuEChERS (quick easy cheap efficient rugged and safe) extraction for both organisms followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) are developed, validated and finally applied to samples collected during a 6-month experiment in outdoor mesocosms. Very low detection limits are reached, allowing environmentally realistic doses (namely, 0.05, 0.5 and 5 μg/L nominal concentrations) to be employed. The results indicate several metabolites and/or transformation products in each compartment investigated, with concentrations sometimes being greater than that of the parent carbamazepine. Biotic degradation of carbamazepine is demonstrated in water, leading to 10,11-dihydrocarbamazepine and 10,11-epoxycarbamazepine. In sediment, the degradation results in the formation of acridine, and 2- and 3-hydroxycarbamazepine. Finally, in both organisms, a moderate bioaccumulation is observed together with a metabolization leading to 10,11-epoxycarbamazepine in fish and 2-hydroxycarbamazepine in mollusc. Acridone is also present in fish. This study provides new and interesting data, helping to elucidate how chronic exposure to carbamazepine at relevant concentrations may affect impact freshwater ecosystems.

A Simple and Fast Extraction Method for the Determination of Multiclass Antibiotics in Eggs Using LC-MS/MS

The purpose of this study was to develop and validate a simple, fast, and specific extraction method for the analysis of 64 antibiotics from nine classes (including sulfonamides, quinolones, tetracyclines, macrolides, lincosamide, nitrofurans, β-lactams, nitromidazoles, and cloramphenicols) in chicken eggs. Briefly, egg samples were simply extracted with a mixture of acetonitrile-water (90:10, v/v) and 0.1 mol·L^-1 Na₂EDTA solution assisted with ultrasonic. The extract was centrifuged, condensed, and directly analyzed on a liquid chromatography coupled to tandem mass spectrometry. Compared with conventional cleanup methods (passing through solid phase extract cartridges), the established method demonstrated comparable efficiencies in eliminating matrix effects and higher or equivalent recoveries for most of the target compounds. Typical validation parameters including specificity, linearity, matrix effect, limits of detection (LODs) and quantification (LOQs), the decision limit, detection capability, trueness, and precision were evaluated. The recoveries of target compounds ranged from 70.8% to 116.1% at three spiking levels (5, 20, and 50 μg·kg^-1), with relative standard deviations less than 14%. LODs and LOQs were in the ranges of 0.005-2.00 μg·kg^-1 and 0.015-6.00 μg·kg^-1 for all of the antibiotics, respectively. A total of five antibiotics were successfully detected in 22 commercial eggs from local markets. This work suggests that the method is suitable for the analysis of multiclass antibiotics in eggs.

High-performance liquid chromatography - mass spectrometry analysis of the parent drugs and their metabolites in extracts from cress (Lepidium sativum) grown hydroponically in water containing four non-steroidal anti-inflammatory drugs

In this paper the metabolism of four non-steroidal anti-inflammatory drugs, (ketoprofen, mefenamic acid, naproxen, and diclofenac) by cress (Lepidium sativum) is described. Cress was cultivated hydroponically in water spiked with the parent drugs at levels ranging from 0.01mgL^-1 to 1mgL^-1. Employing an approach based on the analysis of the plant extracts by HPLC coupled either with quadrupole-time-of-flight mass spectrometry, or Orbitrap MS or triple quadrupole (QqQ) MS allowed the identification of twenty substances (sixteen metabolites and four parent drugs). Metabolites were formed from the parent drug by hydroxylation or conjugation with polar molecules such as glucose, small organic acids or amino acids. Introducing a pre-concentration step employing solid-phase extraction and using HPLC-QqQ/MS in the multiple reaction monitoring mode enabled the positive detection of 11 of the proposed metabolites next to the four parent components even in plants grown in a 0.01mgL^-1 solution of the tested drugs, which is close to the conditions in real reclaimed waters.

Monitoring, sources, receptors, and control measures for three European Union watch list substances of emerging concern in receiving waters - A 20year systematic review

Pollution of European receiving waters with contaminants of emerging concern (CECs), such as with 17-beta-estradiol (a natural estrogenic hormone, E2), along with pharmaceutically-active compounds diclofenac (an anti-inflammatory drug, DCL) and 17-alpha-ethynylestradiol (a synthetic estrogenic hormone, EE2)) is a ubiquitous phenomenon. These three CECs were added to the EU watch list of emerging substances to be monitoring in 2013, which was updated in 2015 to comprise 10 substances/groups of substances in the field of water policy. A systematic literature review was conducted of 3952 potentially relevant articles over period 1995 to 2015 that produced a new EU-wide database consisting of 1268 publications on DCL, E2 and EE2. European surface water concentrations of DCL are typically reported below the proposed annual average environmental quality standard (AA EQS) of 100ng/l, but that exceedances frequently occur. E2 and EE2 surface water concentrations are typically below 50ng/l and 10ng/l respectively, but these values greatly exceed the proposed AA EQS values for these compounds (0.04 and 0.035ng/l respectively). However, levels of these CECs are frequently reported to be disproportionately high in EU receiving waters, particularly in effluents at control points that require urgent attention. Overall it was found that DCL and EE2 enter European aquatic environment mainly following human consumption and excretion of therapeutic drugs, and by incomplete removal from influent at urban wastewater treatment plants (WWTPs). E2 is a natural hormone excreted by humans which also experiences incomplete removal during WWTPs treatment. Current conventional analytical chemistry methods are sufficiently sensitive for the detection and quantification of DCL but not for E2 and EE2, thus alternative, ultra-trace, time-integrated monitoring techniques such as passive sampling are needed to inform water quality for these estrogens. DCL appears resistant to conventional wastewater treatment while E2 and EE2 have high removal efficiencies that occur through biodegradation or sorption to organic matter. There is a pressing need to determine fate and behaviour of these CECs in European receiving waters such as using GIS-modelling of river basins as this will identify pressure points for informing priority decision making and alleviation strategies for upgrade of WWTPs and for hospital effluents with advanced treatment technologies. More monitoring data for these CECs in receiving waters is urgently needed for EU legislation and effective risk management.

Analysis, occurrence, fate and risks of proton pump inhibitors, their metabolites and transformation products in aquatic environment: A review

Proton pump inhibitors (PPIs) which include omeprazole, esomeprazole, lansoprazole, pantoprazole and rabeprazole, are extensively used for the relief of gastro-intestinal disorders. Despite their high worldwide consumption, PPIs are extensively metabolized in human bodies and therefore are not regularly detected in monitoring studies. Very recently, however, it has been shown that some omeprazole metabolites may enter and are likely to persist in aquatic environment. Hence, to fully assess the environmental exposures and risks associated with PPIs, it is important to better understand and evaluate the fate and behavior not only of the parent compound but also of their metabolites and their transformation products arising from biotic and abiotic processes (hydrolysis, photodegradation, biodegradation etc.) in the environment. In this light, the purpose of this review is to summarize the present state of knowledge on the introduction and behavior of these chemicals in natural and engineering systems and highlight research needs and gaps. It draws attention to their transformation, the increase contamination by their metabolites/TPs in different environmental matrices and their potential adverse effects in the environment. Furthermore, existing research on analytical developments with respect to sample treatment, separation and detection of PPIs and their metabolites/TPs is provided.

Illicit drugs and their metabolites in 36 rivers that drain into the Bohai Sea and north Yellow Sea, north China

Illicit drugs and their metabolites have recently been recognized as an emerging group of contaminants due to their potential ecotoxicological impact in aquatic ecosystems. To date, information on the occurrence of these compounds in the aquatic environment of China remains limited. In this study, we collected surface water samples from 36 rivers in north China that discharge into the Bohai Sea and north Yellow Sea and measured the concentrations of amphetamine-like compounds, ketamines, cocainics, and opioids. The occurrence and spatial patterns of these substances show significant differences between the rivers and regions. Two designer drugs, methamphetamine (METH) and ketamine (KET), were the most abundant compounds detected in the entire set of samples (detection frequency of 92 and 69 %). The concentrations of METH and KET ranged from <0.1 to 42.0 ng L(-1) (mean = 4.53 ng L(-1)) and <0.05 to 4.50 ng L(-1) (mean = 0.49 ng L(-1)), respectively. The high detection frequencies of METH and KET are consistent with the fact that they are the main illicit drugs consumed in China. The high concentrations of these illicit drugs and their metabolites were found in areas that have a high population density. The riverine input of total illicit drugs into the Bohai Sea and north Yellow Sea was estimated to be in the range of 684 to 1160 kg per year.

Rapid Screening for Exposure to "Non-Target" Pharmaceuticals from Wastewater Effluents by Combining HRMS-Based Suspect Screening and Exposure Modeling

Active pharmaceutical ingredients (APIs) have raised considerable concern over the past decade due to their widespread detection in water resources and their potential to affect ecosystem health. This triggered many attempts to prioritize the large number of known APIs to target monitoring efforts and testing of fate and effects. However, so far, a comprehensive approach to screen for their presence in surface waters has been missing. Here, we explore a combination of an automated suspect screening approach based on liquid chromatography coupled to high-resolution mass spectrometry and a model-based prioritization using consumption data, readily predictable fate properties and a generic mass balance model for activated sludge treatment to comprehensively detect APIs with relevant exposure in wastewater treatment plant effluents. The procedure afforded the detection of 27 APIs that had not been covered in our previous target method, which included 119 parent APIs. The newly detected APIs included seven compounds with a high potential for bioaccumulation and persistence, and also three compounds that were suspected to stem from point sources rather than from consumption as medicines. Analytical suspect screening proved to be more selective than model-based prioritization, making it the method of choice for focusing analytical method development or fate and effect testing on those APIs most relevant to the aquatic environment. However, we found that state-of-the-practice exposure modeling used to predict potential high-exposure substances can be a useful complement to point toward oversights and known or suspected detection gaps in the analytical method, most of which were related to insufficient ionization.

Universal method to determine acidic licit and illicit drugs and personal care products in water by liquid chromatography quadrupole time-of-flight

Pharmaceuticals, illicit drugs and personal care products are emerging contaminants widely distributed in water. Currently, a number of solid-phase extraction (SPE) procedures followed by liquid chromatography tandem mass spectrometry (LC-MS/MS) have been reported. However, target analysis of selected compounds is commonly used whereas other related contaminants present in the sample remain invisible. Carmona et al. [1] described a method for determining 21 emerging contaminants by LC-MS/MS with improved mobile phases. We tested this protocol in combination with high resolution mass spectrometry using a quadrupole time-of-flight (QqTOF) instrument to get a wide non-target screening approach in order to have a broader scope and more practical method for detecting licit and illicit drugs and personal care products than traditional target methods. The essential points in the method are: •The screening capabilities of QqTOF (ABSciex Triple TOF™) are used for detecting and identifying non-target pharmaceuticals and a large number of other emerging contaminants in water.•The quantitative features of the instrument, the Achilles heel of the QqTOF mass spectrometers, are established for few selected compounds.•The method may be applied to identify a large number of emerging contaminants in water. However, pre-validation will be needed to quantify them.

Critical review on the stability of illicit drugs in sewers and wastewater samples

Wastewater-based epidemiology (WBE) applies advanced analytical methods to quantify drug residues in wastewater with the aim to estimate illicit drug use at the population level. Transformation processes during transport in sewers (chemical and biological reactors) and storage of wastewater samples before analysis are expected to change concentrations of different drugs to varying degrees. Ignoring transformation for drugs with low to medium stability will lead to an unknown degree of systematic under- or overestimation of drug use, which should be avoided. This review aims to summarize the current knowledge related to the stability of commonly investigated drugs and, furthermore, suggest a more effective approach to future experiments. From over 100 WBE studies, around 50 mentioned the importance of stability and 24 included tests in wastewater. Most focused on in-sample stability (i.e., sample preparation, preservation and storage) and some extrapolated to in-sewer stability (i.e., during transport in real sewers). While consistent results were reported for rather stable compounds (e.g., MDMA and methamphetamine), a varying range of stability under different or similar conditions was observed for other compounds (e.g., cocaine, amphetamine and morphine). Wastewater composition can vary considerably over time, and different conditions prevail in different sewer systems. In summary, this indicates that more systematic studies are needed to: i) cover the range of possible conditions in sewers and ii) compare results more objectively. To facilitate the latter, we propose a set of parameters that should be reported for in-sewer stability experiments. Finally, a best practice of sample collection, preservation, and preparation before analysis is suggested in order to minimize transformation during these steps.

Tidal impact on the dynamic behavior of dissolved pharmaceuticals in the Yangtze Estuary, China

The dynamic behavior of 24 dissolved pharmaceuticals over tidal cycles in the Yangtze Estuary, China was studied to assess the tidal impact on the fate of pharmaceutical residues. The results show that most pharmaceuticals were frequently detected with concentrations from below detection to 27.2 ng/L, with sulfamethoxazole, sulfamethazine, erythromycin, thiamphenicol and florfenicol dominating. During tidal cycles, pharmaceutical concentrations decreased during tidal rise, then increasing during tidal receding for all locations, except at site S2 which showed an opposite trend due to unique water movement there. It was observed that most compounds showed a non-conservative behavior, while diazepam and sulfamethoxazole displayed a conservative behavior. The pharmaceutical concentrations were found to increase with dissolved organic carbon (DOC) concentration, suggesting DOC as a carrier of pharmaceuticals. In addition, many compounds showed a significant negative relationship with suspended particulate matter (SPM) concentration, indicating SPM-water interactions as a control of pharmaceutical behavior in estuarine environment.

Pharmaceuticals in the freshwater invertebrate, Gammarus pulex, determined using pulverised liquid extraction, solid phase extraction and liquid chromatography-tandem mass spectrometry

The development, characterisation and application of a new analytical method for multi-residue PPCP determination in the freshwater amphipod, Gammarus pulex are presented. Analysis was performed using pulverised liquid extraction (PuLE), solid phase extraction (SPE) and liquid chromatography-tandem mass spectrometry (LC-MS/MS). Qualitative method performance offered excellent limits of detection at <20 ng g(-1) for 18 out of 29 compounds. For quantitative application, linearity and precision were considered acceptable for 10 compounds across the ng-μg g(-1) range (R2≥0.99; ≤20% relative standard deviation respectively). The method was applied to the analysis of G. pulex and river water sourced from six tributaries of the River Thames. Carbamazepine, diazepam, nimesulide, trimethoprim and warfarin were determined in G. pulex samples at low ng g(-1) (dry weight) concentrations across these sites. Temazepam and diclofenac were also detected, but were not quantifiable. Six pharmaceuticals were quantified in surface waters across the eight sites at concentrations ranging from 3 to 344 ng L(-1). The possibility for confirmatory detection and subsequent quantification of pharmaceutical residues in benthic organisms such as G. pulex will enable further understanding on the susceptibility and ecological effects of PPCPs in the aquatic environment.