Drugs of abuse and their metabolites in river sediments: Analysis, occurrence in four Spanish river basins and environmental risk assessment.

The environmental impact produced by the presence of drugs of abuse in sediments has been scarcely studied to date, even though many of them may adsorb onto particulate matter due to their physical-chemical properties. This study presents an analytical method for the determination of 20 drugs of abuse and metabolites in sediments. The validated method was satisfactory in terms of linearity (r2 >0.99), recovery (90-135 %), repeatability (relative standard deviations <15 %), sensitivity (limits of quantification <2.1 ng/g d.w, except for cannabinoids), and matrix effects (ionization suppression <40 %). The method was applied to the analysis of 144 sediments collected in four Spanish river basins. Cocaine, methadone, and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) were the most ubiquitous compounds (detection frequencies>36 %), whereas cannabinol, Δ9-tetrahydrocannabinol (THC), and methadone were the most abundant compounds (up to 44, 37, and 33 ng/g d.w, respectively). The presence of EDDP, THC, and methadone in the sediments of 28 locations may pose a risk to sediment-dwelling organisms. To the author`s knowledge, this is the most extensive study conducted so far on the occurrence of drugs of abuse in sediments, and the first time that sediment-water distribution coefficients for EDDP, methadone, MDMA, and diazepam are reported from field observations.

Spatio-temporal assessment of illicit drug use at large scale: evidence from 7 years of international wastewater monitoring.

BACKGROUND AND AIMS: Wastewater-based epidemiology is an additional indicator of drug use that is gaining reliability to complement the current established panel of indicators. The aims of this study were to: (i) assess spatial and temporal trends of population-normalized mass loads of benzoylecgonine, amphetamine, methamphetamine and 3,4-methylenedioxymethamphetamine (MDMA) in raw wastewater over 7 years (2011-17); (ii) address overall drug use by estimating the average number of combined doses consumed per day in each city; and (iii) compare these with existing prevalence and seizure data. DESIGN: Analysis of daily raw wastewater composite samples collected over 1 week per year from 2011 to 2017. SETTING AND PARTICIPANTS: Catchment areas of 143 wastewater treatment plants in 120 cities in 37 countries. MEASUREMENTS: Parent substances (amphetamine, methamphetamine and MDMA) and the metabolites of cocaine (benzoylecgonine) and of Δ9 -tetrahydrocannabinol (11-nor-9-carboxy-Δ9 -tetrahydrocannabinol) were measured in wastewater using liquid chromatography-tandem mass spectrometry. Daily mass loads (mg/day) were normalized to catchment population (mg/1000 people/day) and converted to the number of combined doses consumed per day. Spatial differences were assessed world-wide, and temporal trends were discerned at European level by comparing 2011-13 drug loads versus 2014-17 loads. FINDINGS: Benzoylecgonine was the stimulant metabolite detected at higher loads in southern and western Europe, and amphetamine, MDMA and methamphetamine in East and North-Central Europe. In other continents, methamphetamine showed the highest levels in the United States and Australia and benzoylecgonine in South America. During the reporting period, benzoylecgonine loads increased in general across Europe, amphetamine and methamphetamine levels fluctuated and MDMA underwent an intermittent upsurge. CONCLUSIONS: The analysis of wastewater to quantify drug loads provides near real-time drug use estimates that globally correspond to prevalence and seizure data.

Psychoactive pharmaceuticals and illicit drugs in coastal waters of North-Western Spain: Environmental exposure and risk assessment.

The knowledge on the presence of pharmaceutical compounds, and possible risks, in coastal and marine systems is still limited. This study represents the first attempt at monitoring psychoactive pharmaceuticals (PaPs) (benzodiazepines and anxiolytics) and illicit drugs (IDs) in the Rías Baixas coastal area of Northwestern Spain, an area of economic and ecological relevance, leader in shellfish production. Fourteen PaPs and 9 IDs were detected in the water samples with venlafaxine (59%), benzoylecgonine (40%), EDDP (40%), and citalopram (36%) showing the highest detection frequencies. The highest concentrations were measured for venlafaxine (291 ng L-1), benzoylecgonine (142 ng L-1), lorazepam (95.9 ng L-1), and citalopram (92.5 ng L-1). Risk assessment, based on hazard quotients suggested that venlafaxine, citalopram, sertraline, and EDDP were present in concentrations potentially able to cause chronic effects in exposed organisms. Based on the results obtained further monitoring of venlafaxine, citalopram, and EDDP in coastal waters is recommended.

A fully automated approach for the analysis of 37 psychoactive substances in raw wastewater based on on-line solid phase extraction-liquid chromatography-tandem mass spectrometry.

This work presents a multi-residue method for the simultaneous determination of 37 legal and illicit psychoactive substances in wastewater, including the most common illicit drugs (cocaine-related compounds, amphetamine-type stimulants, hallucinogens, opiates/opioids, and cannabinoids), new psychoactive substances (two synthetic cathinones, the synthetic opioid AH-7921, and the arylcyclohexylamine methoxetamine), and legal but controlled psychoactive substances (stimulants, benzodiazepines, antidepressants, sedatives, antipsychotics, and hypnotics). To this end a fully automated analytical approach based on solid phase extraction coupled in series to liquid chromatography tandem mass spectrometry detection (on-line SPE- LC-MS/MS) was used. The methodology developed was validated in terms of linearity, recovery, repeatability, and sensitivity in wastewater. Method linearity was between 0.1 ng/L (or the analyte limit of quantification if higher) and 2,000 ng/L (10,250 ng/L in the case of caffeine). Absolute recoveries were variable (between 5% and 132%), depending on the analyte. However, the use of isotopically labeled compounds corrected for analyte losses during the extraction process and matrix effects (relative recoveries within the range of 80-120%). Repeatability of the method was satisfactory for all analytes, with RSD values lower than 13% for most compounds. Limits of detection and quantification in wastewater were below 7 and 23 ng/L, respectively, for all analytes except lormetazepam (10 and 32 ng/L), caffeine (13 and 44 ng/L), and the cannabinoids 11-nor-9-carboxy- Δ9-tetrahydrocannabinol (18 and 61 ng/L) and 11-hydroxy-Δ9- tetrahydrocannabinol (69 and 228 ng/L). The method was applied to the analysis of wastewater samples collected daily in Barcelona for one week. Twenty-five of the 37 analytes were detected in the samples analyzed. Average concentrations ranged from 7 ng/L in the case of zolpidem to 54 µg/L in the case of caffeine.

Simultaneous LC-MS/MS determination of 40 legal and illegal psychoactive drugs in breast and bovine milk.

This work presents a fast, sensitive and reliable multi-residue methodology based on fat and protein precipitation and liquid chromatography-tandem mass spectrometry for the determination of common legal and illegal psychoactive drugs, and major metabolites, in breast milk. One-fourth of the 40 target analytes is investigated for the first time in this biological matrix. The method was validated in breast milk and also in various types of bovine milk, as tranquilizers are occasionally administered to food-producing animals. Absolute recoveries were satisfactory for 75% of the target analytes. The use of isotopically labeled compounds assisted in correcting analyte losses due to ionization suppression matrix effects (higher in whole milk than in the other investigated milk matrices) and ensured the reliability of the results. Average method limits of quantification ranged between 0.4 and 6.8 ng/mL. Application of the developed method showed the presence of caffeine in breast milk samples (12-179 ng/mL).

Does the presence of caffeine in the marine environment represent an environmental risk? A regional and global study.

Caffeine is an emerging contaminant considered to be an indicator of human contamination that has been widely detected in various aquatic systems, especially in continental waters. Nevertheless, the extent of its possible environmental impact is yet to be determined. This study determined the presence of caffeine, and evaluated the environmental hazard posed by this substance, in the "Rías Gallegas", a series of costal inlets in north-west Spain which are of great ecological value and in which fishing and bivalve farming, are a significant source of income. Caffeine was found to be present at concentrations higher than the limit of quantification (LOQ=3.07ngL-1) in 15 of the 23 samples analysed, with the highest seawater concentration being 857ngL-1 (the highest measured in seawater in Spain). Six out of 22 seawater samples resulted in a hazard quotient (HQ) from chronic exposure higher than 1 with the highest being 17.14, indicating a high probability of adverse effects in the aquatic environment. Environmental Exposure Distributions (EEDs) generated from a literature review of caffeine levels reported previously in four out of the five continents, showed that 28% of all seawater samples, and 69% of all estuary water samples where caffeine has ever been measured resulted in HQ>1 for chronic exposure. Further studies into the potential adverse effects that may arise from exposure to caffeine in aquatic systems are still required. Indeed, the need to gain a more in-depth understanding of the long-term ecotoxicological effects of caffeine is essential to ensure the quality of our health and environment.

Five-year monitoring of 19 illicit and legal substances of abuse at the inlet of a wastewater treatment plant in Barcelona (NE Spain) and estimation of drug consumption patterns and trends.

Illicit and legal drugs of abuse, including alcohol, continue to be in the focus of many governmental national and international studies due to the important consequences of their consumption at both individual and social level. Estimation of drug use at the community level from the concentrations of the drugs themselves or their major metabolites measured in wastewater has become an increasingly accepted and extended tool, complementary to the methods traditionally used for this purpose. The present work describes the application of this approach, generally known as wastewater epidemiology, to investigate the latest drug consumption patterns and trends in the European city of Barcelona. To this end, a total of 19 selected drugs of abuse and metabolites were monitored at the inlet of one of the main wastewater treatment plants of Barcelona every day during one week in March between 2011 and 2015. Analysis of the selected drugs and metabolites in the wastewater samples was performed by means of two methodologies based on liquid chromatography-tandem mass spectrometry (LC-MS/MS), and the concentrations obtained were translated into consumption data. In agreement with official records, alcohol, followed by cannabis, cocaine, amphetamine-like compounds, and methadone were the most consumed drugs. Alcohol, cannabis, and cocaine consumption were on average 18mL(14g)/day/inhabitant (>15), 38g/day/1000 inhabitants aging 15-64, and 2.4g/day/1000 inhabitants aging 15-64, respectively. As for drug use trends, consumption increased over the 5years monitored for all drugs, but for heroin and diazepam. Weekly profiles characterized by higher consumption over the weekend as compared to weekdays were observed only for alcohol, cocaine, and MDMA. Extrapolation of the data obtained for the area under study to the national Spanish territory yields consumption figures of 142t of illicit drugs per year and >2500 million euro turnover per year in the black market.

Occurrence of pharmaceutical, recreational and psychotropic drug residues in surface water on the northern Antarctic Peninsula region.

Human presence in the Antarctic is increasing due to research activities and the rise in tourism. These activities contribute a number of potentially hazardous substances. The aim of this study is to conduct the first characterisation of the pharmaceuticals and recreational drugs present in the northern Antarctic Peninsula region, and to assess the potential environmental risk they pose to the environment. The study consisted of a single sampling of ten water samples from different sources, including streams, ponds, glacier drains, and a wastewater discharge into the sea. Twenty-five selected pharmaceuticals and 21 recreational drugs were analysed. The highest concentrations were found for the analgesics acetaminophen (48.74 µg L-1), diclofenac (15.09 µg L-1) and ibuprofen (10.05 µg L-1), and for the stimulant caffeine (71.33 µg L-1). All these substances were detected in waters that were discharged directly into the ocean without any prior purification processes. The hazard quotient (HQ) values for ibuprofen, diclofenac and acetaminophen were far in excess of 10 at several sampling points. The concentrations of each substance measured and used as measured environmental concentration values for the HQ calculations are based on a one-time sampling. The Toxic Unit values indicate that analgesics and anti-inflammatories are the therapeutic group responsible for the highest toxic burden. This study is the first to analyse a wide range of substances and to determine the presence of pharmaceuticals and psychotropic drugs in the Antarctic Peninsula region. We believe it can serve as a starting point to focus attention on the need for continued environmental monitoring of these substances in the water cycle, especially in protected regions such as the Antarctic. This will determine whether pharmaceuticals and recreational drugs are hazardous to the environment and, if so, can be used as the basis for risk-assessment studies to prioritise the exposure to risk.

Occurrence of drugs of abuse in surface water from four Spanish river basins: Spatial and temporal variations and environmental risk assessment.

The present work investigates the occurrence of 22 drugs of abuse (DAs) and metabolites in surface water from four Spanish River basins: Llobregat, Ebro, Jucar and Guadalquivir. To this end, samples were collected from 77 selected sites in two sampling campaigns conducted in 2010 and 2011. Analyses were performed by means of on-line solid phase extraction-liquid chromatography-electrospray-tandem mass spectrometry (on-line SPE-LC-ESI-MS/MS). Cocaine, its metabolite benzoylecgonine, ephedrine, MDMA (ecstasy), and methadone and its metabolite EDDP were the most ubiquitous compounds, being present in more than 50% of the samples. Overall, DAs were present at low ng/L levels, showing comparatively higher concentrations in small tributary rivers impacted by wastewater treatment plant effluents. The results obtained did not show a clear relationship between the concentrations of DAs and the hydrological conditions of the river basins. Differences in the occurrence of DAs between river basins were observed, but only for MDMA this finding could be confirmed in both sampling campaigns. These results overall suggest similar drugs consumption in the studied areas. Estimation of potential ecotoxicological effects using Hazard Quotient (HQ) ratios and a concentration addition model showed that in four samples the presence of DAs could represent certain risk to aquatic organisms.

Comparative measurement and quantitative risk assessment of alcohol consumption through wastewater-based epidemiology: An international study in 20 cities.

Quantitative measurement of drug consumption biomarkers in wastewater can provide objective information on community drug use patterns and trends. This study presents the measurement of alcohol consumption in 20 cities across 11 countries through the use of wastewater-based epidemiology (WBE), and reports the application of these data for the risk assessment of alcohol on a population scale using the margin of exposure (MOE) approach. Raw 24-h composite wastewater samples were collected over a one-week period from 20 cities following a common protocol. For each sample a specific and stable alcohol consumption biomarker, ethyl sulfate (EtS) was determined by liquid chromatography coupled to tandem mass spectrometry. The EtS concentrations were used for estimation of per capita alcohol consumption in each city, which was further compared with international reports and applied for risk assessment by MOE. The average per capita consumption in 20 cities ranged between 6.4 and 44.3L/day/1000 inhabitants. An increase in alcohol consumption during the weekend occurred in all cities, however the level of this increase was found to differ. In contrast to conventional data (sales statistics and interviews), WBE revealed geographical differences in the level and pattern of actual alcohol consumption at an inter-city level. All the sampled cities were in the "high risk" category (MOE<10) and the average MOE for the whole population studied was 2.5. These results allowed direct comparisons of alcohol consumption levels, patterns and risks among the cities. This study shows that WBE can provide timely and complementary information on alcohol use and alcohol associated risks in terms of exposure at the community level.

Comprehensive monitoring of the occurrence of 22 drugs of abuse and transformation products in airborne particulate matter in the city of Barcelona.

In recent years monitoring the presence of psychotropic compounds in wastewater has been proposed as a tool to estimate community drug use. Measurement of drugs of abuse (DAs) in airborne particulate is currently being explored as an additional tool to evaluate drug use patterns in time and space, and identify potential emission sources. In this study, we comprehensively monitor the occurrence of 22 licit and illicit DAs and transformation products, belonging to 6 different chemical groups, in airborne particulate matter (PM10) in the city of Barcelona. In order to study spatial and temporal variations, samples were collected from 12 different selected locations on one weekday (Wednesday) and one weekend day (Saturday), during five consecutive weeks. A previously developed analytical methodology, based on pressurized liquid extraction (PLE) followed by liquid chromatography-tandem mass spectrometry (LC-MS/MS) determination, was adapted for analysis of the target compounds with satisfactory performance, ensuring reliability of results. Among the investigated compounds, cannabinol (CBN), cocaine (COC), and methamphetamine (MA) were found to be the most ubiquitous and abundant compounds in PM10 with concentrations ranging from 0.7pg/m(3) (MA) to 6020pg/m(3) (CBN). Significant differences in total DA concentrations in PM10 were observed across sampling days and locations. DA emissions were identified in highly densely populated areas, where popular commercial and nightlife zones are located. Psychoactive effects due to inhalation of measured concentrations are probably negligible; however, potential health effects due to chronic exposure have not been explored yet.

Transcriptomic, biochemical and individual markers in transplanted Daphnia magna to characterize impacts in the field.

Daphnia magna individuals were transplanted across 12 sites from three Spanish river basins (Llobregat, Ebro, Jucar) showing different sources of pollution. Gene transcription, feeding and biochemical responses in the field were assessed and compared with those obtained in re-constituted water treatments spiked with organic eluates obtained from water samples collected at the same locations and sampling periods. Up to 166 trace contaminants were detected in water and classified by their mode of action into 45 groups that included metals, pharmaceuticals, pesticides, illicit drugs, and other industrial compounds. Physicochemical water parameters differentiated the three river basins with Llobregat having the highest levels of conductivity, metals and pharmaceuticals, followed by Ebro, whereas the Jucar river had the greatest levels of illicit drugs. D. magna grazing rates and cholinesterase activity responded similarly than the diversity of riparian benthic communities. Transcription patterns of 13 different genes encoding for general stress, metabolism and energy processes, molting and xenobiotic transporters corroborate phenotypic responses differentiated sites within and across river basins. Principal Component Analysis and Partial Least Square Projections to Latent Structures regression analyses indicated that measured in situ responses of most genes and biomarkers and that of benthic macroinvertebrate diversity indexes were affected by distinct environmental factors. Conductivity, suspended solids and fungicides were negatively related with the diversity of macroinvertebrates cholinesterase, and feeding responses. Gene transcripts of heat shock protein and metallothionein were positively related with 11 classes of organic contaminants and 6 metals. Gene transcripts related with signaling paths of molting and reproduction, sugar, protein and xenobiotic metabolism responded similarly in field and lab exposures and were related with high residue concentrations of analgesics, diuretics, psychiatric drugs, ß blockers, illicit drugs, trizoles, bisphenol A, caffeine and pesticides. These results indicate that application of omic technologies in the field is a promising subject in water management.

Analysis of ethyl sulfate in raw wastewater for estimation of alcohol consumption and its correlation with drugs of abuse in the city of Barcelona.

The increasing, generalized consumption of alcohol, especially among young people, generates great concern in our society due to its negative consequences on public health and safety. Besides the traditional, official methods employed for estimation of alcohol consumption, the monitoring of ethyl sulfate (EtS), a urinary biomarker of alcohol ingestion, in raw wastewater has been recently proposed as an additional tool to estimate alcohol use at community level through the so-called sewage epidemiology approach. In the presented study, a fast and reliable analytical method based on ion-pair liquid chromatography-tandem mass spectrometry (LC-MS/MS) has been optimized and further applied to the analysis of EtS in seven 24h composite samples collected along one week at the inlet of a large sewage treatment plant (STP) located in the Barcelona area. EtS was measured in the entire set of analysed samples, with concentrations ranging from 5.5 to 33µg/L, which correspond to an absolute alcohol consumption of around 11,000 (Wednesday) to 25,000 (Sunday) kg/day. The average per capita absolute alcohol consumption calculated was 18mL/day/inhabitant. Moreover, the levels of EtS measured throughout the week showed high correlation with those of some recreational illicit drugs and metabolites, namely, cocaethylene (r(2)=0.9391, n=5), benzoylecgonine (r(2)=0.9252, n=7), ecstasy (r(2)=0.8950, n=7), amphetamine (r(2)=0.8707, n=7) and cocaine (r(2)=0.6425, n=7), measured in the same samples. This study confirms that the analysis of EtS in raw wastewater can be a useful tool for the estimation of alcohol consumption in an anonymous, fast and economic way, and indicates that consumption of alcohol and some illicit drugs occurs often together.

Spatial differences and temporal changes in illicit drug use in Europe quantified by wastewater analysis.

AIMS: To perform wastewater analyses to assess spatial differences and temporal changes of illicit drug use in a large European population. DESIGN: Analyses of raw wastewater over a 1-week period in 2012 and 2013. SETTING AND PARTICIPANTS: Catchment areas of wastewater treatment plants (WWTPs) across Europe, as follows: 2012: 25 WWTPs in 11 countries (23 cities, total population 11.50 million); 2013: 47 WWTPs in 21 countries (42 cities, total population 24.74 million). MEASUREMENTS: Excretion products of five illicit drugs (cocaine, amphetamine, ecstasy, methamphetamine, cannabis) were quantified in wastewater samples using methods based on liquid chromatography coupled to mass spectrometry. FINDINGS: Spatial differences were assessed and confirmed to vary greatly across European metropolitan areas. In general, results were in agreement with traditional surveillance data, where available. While temporal changes were substantial in individual cities and years (P ranging from insignificant to <10(-3) ), overall means were relatively stable. The overall mean of methamphetamine was an exception (apparent decline in 2012), as it was influenced mainly by four cities. CONCLUSIONS: Wastewater analysis performed across Europe provides complementary evidence on illicit drug consumption and generally concurs with traditional surveillance data. Wastewater analysis can measure total illicit drug use more quickly and regularly than is the current norm for national surveys, and creates estimates where such data does not exist.

Multianalyte determination of 24 cytostatics and metabolites by liquid chromatography-electrospray-tandem mass spectrometry and study of their stability and optimum storage conditions in aqueous solution.

A multianalyte liquid chromatography-electrospray-tandem mass spectrometry (LC-ESI-MS/MS) method for determination of 19 cytostatics and 5 metabolites, from 6 different therapeutic families, has been developed, and the structures of the main characteristic fragment ions have been proposed. Instrumental limits of detection and quantification are in the range 0.1-10.3 and 1.0-34.3 ng mL(-1), respectively. Moreover, the stability of the compounds in aqueous solution was investigated in order to establish the best conditions for preparation and storage of both calibration standards and water samples. Dimethylsulphoxide (DMSO) was selected as solvent for preparation of the stock solutions. At room temperature (25 °C), 11 of the 24 target compounds were shown to be unstable in water (percentage of organic solvent 4%), with concentration losses greater than 20% in less than 24 h. At 4 °C (typical storage temperature for water samples) all compounds, except MTIC and chlorambucil, were stable for 24h, but the number of stable compounds decreased to 10 after 9 days. Freezing of the aqueous solutions improved considerably the stability of various compounds: after 3 months of storage at -20 °C, 10 compounds, namely, 5-fluorouracil, carboplatin, gemcitabine, temozolomide, vincristine, vinorelbine, ifosfamide, cyclophosphamide, etoposide, and capecitabine, remained stable (in contrast to only carboplatin and capecitabine at 4 °C). The addition of acid improved the stability of methotrexate and its metabolite hydroxy-methotrexate but not that of the rest of compounds. The addition of organic solvent (50% methanol or DMSO) prevented the degradation at 4 °C of the otherwise unstable compounds oxaliplatin, methotrexate, erlotinib, doxorubicin, tamoxifen, and paclitaxel. To the authors' knowledge, five of the analytes investigated have never been searched for in the aquatic environment (imatinib, 6α-hydroxypaclitaxel, endoxifen, (Z)4-hydroxytamoxifen, and temozolomide), and for many of them the stability data provided, and even the analytical LC-MS/MS conditions, are the first ever published.

Illicit and abused drugs in sewage sludge: method optimization and occurrence.

A sensitive and reliable method for the determination of 20 abused and illicit drugs and their metabolites in sewage sludge has been developed and validated. To the authors' knowledge, nine out of the 20 selected analytes, namely, cocaethylene, ephedrine, heroin, alprazolam, lysergic acid diethylamide (LSD), its metabolite 2-oxo-3-hydroxy-LSD, and the cannabinoids Δ(9)-tetrahydrocannabinol (THC), cannabinol (CBN) and cannabidiol (CBD), are investigated for the first time in this matrix. In the optimized approach, freeze-dried sewage sludge samples were extracted by means of pressurized liquid extraction, and the extracts were further cleaned-up by solid phase extraction. Analytes were determined by liquid chromatography coupled to tandem mass spectrometry. Method limits of quantification were below 3.3ng/g d.w. for all compounds but cannabinoids (8.2-22.5ng/g d.w.). Method repeatability was below 14% for most compounds. Overall method recoveries were low due to the presence of matrix interferences that could not be completely eliminated and suppressed the ionization of the target analytes between 26% and 89%. However, extraction losses and matrix effects were satisfactorily corrected through the use of isotopically labeled analogs as surrogate standards, ensuring reliable results. The method was applied to the analysis of various sewage sludge samples. Cannabinoids, methadone and its metabolite 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) were the most ubiquitous and abundant compounds, showing maximum concentrations above 100ng/g d.w. in all cases (up to 579ng/g d.w. in the case of THC). This work is the first evidence of the presence of the cannabinoids CBN, CBD, and THC in sewage sludge.

Fully automated determination of nine ultraviolet filters and transformation products in natural waters and wastewaters by on-line solid phase extraction-liquid chromatography-tandem mass spectrometry.

This paper describes the development and validation of the first fully automated method, based on on-line solid phase extraction-liquid chromatography-tandem mass spectrometry (on line-SPE-LC-MS/MS), for the determination of UV filters (UV F) and transformation products, with a wide range of physicochemical properties. The developed method was validated and applied to the analysis of the selected compounds in river water (RW), groundwater (GW), influent and effluent wastewater (IWW and EWW). Comparing with the off-line methodologies published so far the presented method provides several advantages including a shorter extraction time, lower sample volume and minimum manipulation. Low limits of detection were achieved for all the studied matrices, <3ng/L (GW), <3.5ng/L (RW), <4ng/L (EWW) and <10ng/L (IWW), allowing a reliable and accurate quantification of the analytes at trace level. SPE optimization and critical aspects associated with the trace level determination of the target compounds (e.g. matrix effects) have been also considered and discussed. The method was successfully applied to the analysis of the UV F in five real water samples of each considered matrix, being the first time that these compounds were determined in GW.

Drugs of abuse in urban groundwater. A case study: Barcelona.

This study is concerned with drugs of abuse (DAs) and their metabolites in urban groundwater at field scale in relation to (1) the spatial distribution of DAs in Barcelona's groundwater, (2) the depth of the groundwater samples, (3) the presence of DAs in recharge sources, and (4) the assessment of the fate of DAs in Barcelona aquifers. To this end, 37 urban groundwater samples were collected in the city of Barcelona and a total of 21 drugs were analyzed including cocainics, amphetamine-like compounds, opioids, lysergics and cannabinoids and the prescribed drugs benzodiazepines. Overall, the highest groundwater concentrations (around 200 ng/L in SAP-4) and the largest number of detected DAs were found in zones basically recharged by a river that receives large amounts of effluents from waste water treatment plants (WWTPs). In contrast, the urbanized areas yielded not only lower concentrations but also a much smaller number of drugs, which suggests a local origin. In fact, cocaine and its metabolite were dominant in more prosperous neighborhoods, whereas the cheaper MDMA was the dominant DA in poorer districts. Measured concentrations were consistently smaller than those estimated from the waste water fraction in groundwater samples, suggesting that DAs undergo removal processes in both reducing and oxidizing conditions.