Wastewater-based epidemiology to assess pharmaceutical consumption. Spanish perspective.

Wastewater-based epidemiology (WBE) is a well-established approach that can provide objective and real-time data on the consumption of substances such as pharmaceuticals. However, most of the studies reported so far compares consumption data obtained using WBE with those derived from prescription data from public health systems, which is often incomplete and might represent a source of uncertainty. This study aims to compare the measured pharmaceutical consumption back calculated with the WBE approach with consumption derived from dispensed pharmaceuticals in two regions of Spain, managed by two different Health Systems. To do so, a group of 17 pharmaceuticals, including the most representative ones of every therapeutic family, were monitored in influent wastewater (IWW) samples collected over a week campaign in spring 2022 at four different wastewater treatment plants (WWTPs) in Spain: two WWTPs in Madrid city (center of Spain) and two WWTPs in Catalonia (Northeast of Spain). Population-normalized daily loads (PNDL) revealed that the patterns of pharmaceutical occurrence in the different WWTPs are very similar, being acetaminophen, 4-acetamidoantipyrine and valsartan the pharmaceuticals with the highest PNDL values: 17162 ± 1457 mg day-1 1000 inh-1 for acetaminophen, 2365 ± 696 and 2429 ± 263 mg day-1 1000 inh-1 for 4-acetamidoantipyrine, 2006 ± 541 and 2041 ± 352 mg day-1 1000 inh-1 for valsartan. Pharmaceutical PNLDs were then transformed into measured pharmaceutical consumption (MC) and compared with dispensed consumption (DC) data obtained from the pharmacies in the catchment area where the WWTPs are located. A ratio MC/DC within 0.8 to 1.2 was obtained for 11 out of the 17 studied pharmaceuticals. Highlighting a match in all the cardiovascular system pharmaceuticals, with the exception of losartan (1.29-1.39 ratio) and valsartan (1.35-1.43) in all WWTPs. In summary, the degree of correlation between MC/DC is higher than those previously reported comparing with the prescribed pharmaceutical consumption.

Pharmaceuticals in hospital wastewaters: an analysis of the UBA's pharmaceutical database.

The presence of pharmaceuticals in hospital wastewaters (HWW) has been a focus of interest for researchers in the last decades. Certain therapeutic classes, such as X-ray contrast media, broad-spectrum antimicrobials and cytotoxics among others, are mainly used in hospitals-health care facilities. This study is focused on available studies monitoring the presence of pharmaceuticals in HWW around the world. To that end, the last available version (v3. 2021) of the "Pharmaceuticals in the Environment" database published by the Federal German Environment Agency (Umweltbundesamt) has been used. Almost half of all studies included (107) have been conducted in Europe. Pharmaceuticals have been monitored in HWW in 38 different countries across all five continents. The country with the greatest number of studies is Brazil (11), followed by Spain (8), China (7), and France (6). Our analysis revealed that 271 different pharmaceuticals have been detected at least once in HWW. The five drugs with more studies showing a positive detection are ciprofloxacin (38), sulfamethoxazole (36), diclofenac (34), ibuprofen (29), and trimethoprim (27). A total of 47 out of 271 drugs are considered in the NIOSH "Hazardous drug" list. However, monitoring data for some widely used drugs in hospital settings such as muscle relaxants, anesthetics, and antidotes is lacking. In conclusion, this study provides the first large-scale metadata analysis for the pharmaceuticals in HWW worldwide.

Occurrence and ecological risk assessment of organic UV filters in coastal waters of the Iberian Peninsula.

This study aimed to assess the presence of 21 UVFs and metabolites in coastal regions of the Iberian Peninsula, to evaluate their environmental risk, and identify possible influential factors affecting their measured concentrations. Sampling was carried out in spring and summer to assess possible seasonal variations. UVFs were detected in 43 of the 46 sampling sites. Only 5 were found above LOD: BP4, OC, BP3 and metabolites BP1 and BP8. Samples collected in Mar Menor had the greatest variety of compounds per sample and the highest cumulative concentrations. The risk was characterized using Risk Quotients (RQ). BP1 showed a Low environmental Risk in 2 sites while for OC the RQ indicated a Moderate Risk in 22 points. The variables that contribute most to the variation are population density, sampling season, whether it was an open bay or not, and level of urbanization. The presence of WWTPs had a lower influence.

River waters induced neurotoxicity in an embryo-larval zebrafish model.

Some investigations have revealed an increased release of psychoactive drugs into the aquatic environments near big cities. However, despite the alert generated by the presence of such neurotoxic compounds, there is a lack of studies evaluating the impact on living organisms. One solution consists in the development of bioassays able to address specific risks, such as neurotoxicity, but on the other hand suitable to assess complex matrices like river samples. The objective of this work was to assess surface water toxicity by means of a zebrafish embryo-larval combined toxicity assay, which is based on a variety of toxicological endpoints, especially those related to neurodevelopment. For such a purpose, we selected the Tagus River in which a previous monitoring study revealed the presence of psychoactive drugs. Results showed that most of the toxicological endpoints evaluated remained unaltered in the exposed embryos, except for the tail length that was larger in the exposed larvae, and the locomotor activity in the 6-day larvae, which was decreased in four groups of exposure (n=5 sampling points). In the absence of systemic toxicity, changes in larval locomotion are indicative of neurotoxicity. This result suggests that the Tagus River can convey neurotoxic compounds at levels that may represent an early and specific threat over the aquatic species of vertebrates, what can have dramatic consequences under the ecological point of view.

Biomarker assessment of toxicity with miniaturised bioassays: diclofenac as a case study.

The development of suitable biomarker-based microbioassays with model species with ecological relevance would help increase the cost-efficiency of routine environmental monitoring and chemical toxicity testing. The anti-inflammatory drug diclofenac has been widely reported in the environment but ecotoxicological data are scarce. The aim of this work is to assess the acute and chronic sublethal toxicity of diclofenac in relevant taxa of aquatic and riparian ecosystems (the fish Danio rerio and the fern Polystichum setiferum). Reliable biomarkers of cell viability (mitochondrial activity), plant physiology (chlorophyll), growth (DNA content) or oxidative damage (lipid peroxidation) were assessed as sensitive endpoints of toxicity. DNA quantification shows that diclofenac induces acute lethal phytotoxicity at 24 and 48 h (LOECs 30 and 0.3 µg l(-1), respectively). Hormetic effects in mitochondrial activity in spores of Polystichum setiferum mask lethality, and adverse effects are only observed at 48 h (LOEC 0.3 µg l(-1)). In chronic exposure (1 week) LOEC for DNA is 0.03 µg l(-1). Mitochondrial activity shows a strong hormetic stimulation of the surviving spore population (LOEC 0.3 µg l(-1)). Little changes are observed in chlorophyll autofluorescence (LOEC 0.3 µg l(-1)). A very short exposure (90 min) of zebrafish embryos induces a reduction of lipid peroxidation at 0.03 µg l(-1). Environmental concentrations of diclofenac can be deleterious for the development of significant populations of sensitive individuals in aquatic and riparian ecosystems.

Anthropogenic contaminants in freshwater from the northern Antarctic Peninsula region.

This study aimed to evaluate the presence of ultraviolet filters (UV-Fs), benzotriazoles, pyrethroids and per- and polyfluoroalkyl substances (PFASs) in freshwater and wastewater from the northern Antarctic Peninsula region. All water samples analyzed contained UV-Fs residues and high concentrations were detected in anthropogenic impacted sites (< LOD up to 1300 ng/L). Likewise, benzotriazoles were detected in all water samples (< LOQ-920 ng/L). Regarding suspended particulate matter, almost all UV-Fs and all benzotriazoles were measured at concentrations ranging from < LOQ to 33 µg/g dry weight. Pyrethroids were also detected (< LOQ-250 ng/L) and their presence implies the existence of a gateway to the Antarctica Peninsula from other regions. The data confirmed the presence of PFASs (< LOD-7500 ng/L) in this area, in agreement with previous studies. In light of these results, extended monitoring in Antarctica should be carried out to perform a reliable environmental risk assessment leading to propose recommendations to minimize the anthropic impact.

Assessing population exposure to phthalate plasticizers in thirteen Spanish cities through the analysis of wastewater.

Phthalates are widely used plasticizers that produce endocrine-disrupting disorders. Quantifying exposure is crucial to perform risk assessments and to develop proper health measures. Herein, a wastewater-based epidemiology approach has been applied to estimate human exposure to six of the mostly used phthalates within the Spanish population. Wastewater samples were collected over four weekdays from seventeen wastewater treatment plants serving thirteen cities and ca. 6 million people (12.8 % of the Spanish population). Phthalate metabolite loads in wastewater were transformed into metabolite concentrations in urine and into daily exposure levels to the parent phthalates. Considering all the sampled sites, population-weighted overall means of the estimated concentrations in urine varied between 0.7 ng/mL and 520 ng/mL. Very high levels, compared to human biomonitoring data, were estimated for monomethyl phthalate, metabolite of dimethyl phthalate. This, together with literature data pointing to other sources of this metabolite in sewage led to its exclusion for exposure assessments. For the remaining metabolites, estimated concentrations were closer to those found in urine. Their 4-days average exposure levels ranged from 2 to 1347 µg/(day∙inh), exceeding in some sites the daily exposure thresholds set for di-i-butyl phthalate and di-n-buthyl phthalate by the European Food Safety Authority.

The embodiment of wastewater data for the estimation of illicit drug consumption in Spain.

Data obtained from wastewater analysis can provide rapid and complementary insights in illicit drug consumption at community level. Within Europe, Spain is an important country of transit of both cocaine and cannabis. The quantity of seized drugs and prevalence of their use rank Spain at the top of Europe. Hence, the implementation of a wastewater monitoring program at national level would help to get better understanding of spatial differences and trends in use of illicit drugs. In this study, a national wastewater campaign was performed for the first time to get more insight on the consumption of illicit drugs within Spain. The 13 Spanish cities monitored cover approximately 6 million inhabitants (12.8% of the Spanish population). Untreated wastewater samples were analyzed for urinary biomarkers of amphetamine, methamphetamine, MDMA, cocaine, and cannabis. In addition, weekend samples were monitored for 17 new psychoactive substances. Cannabis and cocaine are the most consumed drugs in Spain, but geographical variations showed, for instance, comparatively higher levels of methamphetamine in Barcelona and amphetamine in Bilbao, with about 1-fold higher consumption of these two substances in such metropolitan areas. For amphetamine, an enantiomeric profiling was performed in order to assure the results were due to consumption and not to illegal dumping of production residues. Furthermore, different correction factors for the excretion of cannabis were used to compare consumption estimations. All wastewater results were compared with previously reported data, national seizure data and general population survey data, were a reasonable agreement was found. Daily and yearly drug consumption were extrapolated to the entire Spanish population with due precautions because of the uncertainty associated. These data was further used to estimate the retail drug market, where for instance cocaine illicit consumption alone was calculated to contribute to 0.2-0.5% of the Spanish gross domestic product (ca. 3000-6000 million Euro/year).

Presence of pharmaceutical compounds, levels of biochemical biomarkers in seafood tissues and risk assessment for human health: Results from a case study in North-Western Spain.

This study assessed the presence of 27 pharmaceutically active compounds belonging to common therapeutic groups (cardiovascular, antiashmatic, psychoactive, diuretic, analgesic/anti-inflammatory, and antibiotic drugs) in the tissues of representative seafood species of bivalves, cephalopods, arthropods, and fish of high economic importance and consumption rates in North-Western Spain. Four pharmaceutical compounds, out of the 27 analyzed, were detected in the collected samples. The benzodiazepine citalopram was detected in the tissues of common octopus (14.1 ng g-1 dry weight) and pod razor (9.4 ng g-1 dw). The anxiolytic venlafaxine was detected in the tissues of common cockle (2.9 ng g-1 dw). The veterinary antiparasitic ronidazole was found in pod razor (2.3 ng g-1 dw) and, finally, the psychoactive compound alprazolam was also measured in common octopus (0.3 ng g-1 dw). Hazard quotients were calculated to assess the hazard posed by the consumption of the sampled seafoods. Octopus and pod razor tissues containing citalopram and alprazolam exceeded our chosen hazard limits (HQ > 0.1) for toddlers who are high consumers of seafood (HQ values between 0.18 and 0.27). A battery of biochemical biomarkers of effects (acetylcholinesterase, glutathione S-transferase; catalase, glutathione peroxidase and glutathione reductase enzymes activities and reduced/oxidized glutathione and malondialdehyde levels) was applied to samples of the study species with the aim of characterizing their basal levels and evaluating their suitability as a tool in the monitoring chronic exposure to environmental contaminants such as those analyzed in this study. According to the measured biomarkers, pod razor and cockles have the potential to be good bioindicator species, based on the observed among-site differences detected on acetylcholinesterase, glutathione S-transferase, catalase, glutathione peroxidase activities; reduced/oxidized glutathione and malondialdehyde levels.

Assessing alcohol consumption through wastewater-based epidemiology: Spain as a case study.

BACKGROUND: In this study, an alternative and complementary method to those approaches currently used to estimate alcohol consumption by the population is described. This method, known as wastewater-based epidemiology (WBE), allows back-calculating the alcohol consumption rate in a given population from the concentrations of a selected biomarker measured in wastewater. METHODS: Composite (24-h) wastewater samples were collected at the inlet of 17 wastewater treatment plants located in 13 Spanish cities for seven consecutive days in 2018. The sampled area covered 12.8% of the Spanish population. Wastewater samples were analyzed to determine the concentration of ethyl sulfate, the biomarker used to back-calculate alcohol consumption. RESULTS: Alcohol consumption ranged from 4.5 to 46 mL/day/inhabitant. Differences in consumption were statistically significant among the investigated cities and between weekdays and weekends. WBE-derived estimates of alcohol consumption were comparable to those reported by its corresponding region in the Spanish National Health Survey in most cases. At the national level, comparable results were obtained between the WBE-derived annual consumption rate (5.7 ± 1.2 L ethanol per capita (aged 15+)) and that reported by the National Health Survey (4.7 L ethanol per capita (aged 15+)). CONCLUSIONS: This is the largest WBE study carried out to date in Spain to estimate alcohol consumption rates. It confirms that this approach is useful for establishing spatial and temporal patterns of alcohol consumption, which could contribute to the development of health care management plans and policies. Contrary to established methods, it allows obtaining information in a fast and relatively economical way.

First nation-wide estimation of tobacco consumption in Spain using wastewater-based epidemiology.

Wastewater-based epidemiology (WBE) has become a very useful tool to monitor a population's drug consumption or exposure to environmental and food contaminants. In this work, WBE has been applied to estimate tobacco consumption in seven Spanish regions. To this end, 24 h composite wastewater samples were taken daily for one week in 17 wastewater treatment plants, covering altogether a population of ca. 6 million inhabitants. The samples were treated by enzymatic deconjugation and the wastewater content of two human-specific nicotine metabolites (namely, cotinine and trans-3'-hydroxycotinine) was measured to estimate the daily consumption of nicotine. The population-weighted average nicotine consumption in the seven analyzed regions was 2.2 g/(day∙1000 inh.), without any daily pattern. This average estimated nicotine consumption value agreed with the value derived from official tobacco sales data. Differences in consumption among the seven studied regions were found, being Galicia, the region with the lowest rate, and the Basque Country and Catalonia those with the highest rates. However, no conclusive correlation was found between those values and the prevalence data taken from two different national surveys, nor sociodemographic and health data. This study demonstrates that this tool can complement other indicators in order to accurately assess tobacco consumption rates at regional and national levels and provides the most extensive application of the approach in the Spanish territory.

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.

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.

[Wastewater-based epidemiology: applications towards the estimation of drugs of abuse consumption and public health in general. The Spanish network ESAR-Net]. / Análisis de aguas residuales con fines epidemiológicos: aplicaciones a la estimación del consumo de sustancias de abuso y en salud pública en general. Red española ESAR-Net.

This manuscript introduces Wastewater-Based Epidemiology (WBE) and its potential in the assessment of diverse aspects related to public health. This methodology can provide data in a relatively short temporal and local scale (typically dialy-weekly at the municipal level) on consumption patterns of illicit drugs (e.g. cocaine or cannabis), licit substances of abuse (e.g. alcohol) by measuring their consumption biomarkers (i.e. the original unmetabolized substance or some of its metabolite) in wastewater. Besides discussing the fundaments, advantages and shortcomings of WBE, it reviews some of the main precedents at international level and most remarkable activities that have been taken place in this field in Spain. Finally, the Spanish Network of Wastewater-Based Epidemiology (ESAR-Net) as is presented. ESAR-Net is an Excellence Network that sums up the efforts of the most relevant Spanish researchers in the field of WBE, aiming to investigate future perspectives of this methodology and its impact on Public Health competences in Spain.

En este artículo se presenta la metodología de análisis de aguas residuales con fines epidemiológicos (wastewater-based epidemiology, WBE) y su potencial para abordar diversos aspectos relacionados con la salud pública. Esta metodología permite obtener datos a una escala temporal y espacial relativamente pequeña (típicamente datos diarios-semanales sobre un municipio) de hábitos de consumo de sustancias de abuso, ilegales (como la cocaína o el cannabis) o legales (como el alcohol) a través de la determinación de biomarcadores de consumo (el compuesto original no metabolizado o alguno de sus metabolitos) en el agua residual. Aparte de discutir los fundamentos, ventajas y limitaciones de WBE, se comentan los precedentes más relevantes a nivel internacional, y las actividades más destacables en España en este ámbito. Finalmente, se exponen, los objetivos de la Red Española de Análisis de Aguas Residuales con Fines Epidemiológicos (ESAR-Net), una "Red de Excelencia" que agrupa a investigadores españoles con amplia experiencia en el área de WBE, así como las perspectivas de futuro de esta metodología puede tener para mejorar las competencias de la Salud Pública en España.

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.

Preliminary data suggest that venlafaxine environmental concentrations could be toxic to plants.

Venlafaxine hydrochloride is a structurally novel antidepressant. Its occurrence in surface waters and drinking water has only been reported in recent works. The aim of this work is to assess the acute and chronic sublethal toxicity of venlafaxine in relevant taxa of riparian ecosystems. We used the fern Polystichum setiferum during the critical life stage of development. Reliable biomarkers of cell viability (mitochondrial activity), plant physiology (chlorophyll), and growth (DNA content) were assessed as sensitive endpoints of toxicity. About DNA quantification, our results show that venlafaxine induces acute lethal phytotoxicity at 24 and 48 h (LOECs 1 µg L(-1) and 0.1 µg L(-1), respectively). At 24 h, hormetic effects in spores of P. setiferum mitochondrial activity mask lethality and adverse effects are observed (LOEC 1 µg L(-1)). At 48 h a reduction in the mitochondrial activity happens (LOEC 10 µg L(-1)). In chronic exposure of 1 week, LOEC for DNA is 0.1 µg L(-1). Mitochondrial activity showed a strong hormetic stimulation of a surviving spore population (LOEC 10 µg L(-1)). Changes were not observed in chlorophyll autofluorescence. Environmental concentrations of venlafaxine can be deleterious for the development of significant populations of sensitive individuals in riparian ecosystems.

Análisis de aguas residuales con fines epidemiológicos: aplicaciones a la estimación del consumo de sustancias de abuso y en salud pública en general. Red española ESAR-Net / Wastewater-based epidemiology: applications towards the estimation of drugs of abuse consumption and public health in general. The Spanish network ESAR-Net

En este artículo se presenta la metodología de análisis de aguas residuales con fines epidemiológicos (wastewater-based epidemiology, WBE) y su potencial para abordar diversos aspectos relacionados con la salud pública. Esta metodología permite obtener datos a una escala temporal y espacial relativamente pequeña (típicamente datos diarios-semanales sobre un municipio) de hábitos de consumo de sustancias de abuso, ilegales (como la cocaína o el cannabis) o legales (como el alcohol) a través de la determinación de biomarcadores de consumo (el compuesto original no metabolizado o alguno de sus metabolitos) en el agua residual. Aparte de discutir los fundamentos, ventajas y limitaciones de WBE, se comentan los precedentes más relevantes a nivel internacional, y las actividades más destacables en España en este ámbito. Finalmente, se exponen, los objetivos de la Red Española de Análisis de Aguas Residuales con Fines Epidemiológicos (ESAR-Net), una "Red de Excelencia " que agrupa a investigadores españoles con amplia experiencia en el área de WBE, así como las perspectivas de futuro de esta metodología puede tener para mejorar las competencias de la Salud Pública en España

This manuscript introduces Wastewater-Based Epidemiology (WBE) and its potential in the assessment of diverse aspects related to public health. This methodology can provide data in a relatively short temporal and local scale (typically dialy-weekly at the municipal level) on consumption patterns of illicit drugs (e.g. cocaine or cannabis), licit substances of abuse (e.g. alcohol) by measuring their consumption biomarkers (i.e. the original unmetabolized substance or some of its metabolite) in wastewater. Besides discussing the fundaments, advantages and shortcomings of WBE, it reviews some of the main precedents at international level and most remarkable activities that have been taken place in this field in Spain. Finally, the Spanish Network of Wastewater-Based Epidemiology (ESAR-Net) as is presented. ESAR-Net is an Excellence Network that sums up the efforts of the most relevant Spanish researchers in the field of WBE, aiming to investigate future perspectives of this methodology and its impact on Public Health competences in Spain

Psychoactive pharmaceutical residues in the watersheds of Galicia (Spain).

OBJECTIVE: To monitor the presence of pharmaceutical residues of 14 psychoactive drugs belonging to three therapeutic groups in the watersheds of Galicia (Spain). METHOD: Five sewage treatment plants were selected in the main cities of Galicia. Thirteen psychoactive pharmaceutical compounds and one metabolite were chosen. In addition, tap water samples were taken from public places and private residences in the selected cities. RESULTS: In all the water samples analyzed, the highest concentrations corresponded to the group of anxiolytics. In particular, high concentrations of lorazepam were found in river and tap water samples. CONCLUSIONS: This investigation demonstrates the presence of psychoactive pharmaceuticals in the watersheds of the autonomous region of Galicia and the conversion of metabolites to parent compounds. This work also shows the need to increase environmental monitoring of watersheds and to improve sewage and drinking water treatment processes to remove these pharmaceuticals.

Pollution by psychoactive pharmaceuticals in the Rivers of Madrid metropolitan area (Spain).

There are a number of reports in the literature which describe the occurrence of so-called emerging pollutants, such as pharmaceuticals, in surface water. Few of these studies have reported values from large cities in relatively arid areas, such as in Spain. The persistence of some pharmaceuticals to usual wastewater treatments allows their discharge into surface waters. It is increasingly evident that mental health problems are of special concern for public health since psychiatric drugs are used in large amounts. Compared to other countries, Spain has a high pharmaceutical consumption rate, and Madrid metropolitan area is one of the most densely populated areas in Europe. The aim of the present study was to determine the presence of different psychoactive pharmaceuticals and metabolites in the main rivers of Madrid metropolitan area: Jarama, Manzanares, Guadarrama, Henares and Tajo. Sampling was done downstream of ten sewage treatment plants (STP) discharging into these rivers. Control points upstream of STPs discharge points were also sampled. Pharmaceutical compounds and metabolites for analysis were selected according to human consumption and prescription rates in Madrid, and the availability of valid techniques for detection. We observed residues of the antidepressants fluoxetine (80% of the sampling sites), citalopram (60%) and venlafaxine (100%), the anxiolytics nordiazepam (90%), oxazepam (80%) and 7-aminoflunitrazepam (10%) and the anticonvulsant carabamazepine (70%). Measured concentrations equalled or exceeded those reported for other geographical areas, although there is a pronounced lack of information for the anxiolytics and venlafaxine. This is of special concern given that Wyeth-Ayerst's venlafaxine, Effexor, was the 10th greatest selling pharmaceutical worldwide in 2006. We conclude that the origin of pharmaceutical pollution in the rivers of Madrid is mainly the discharge of sewage treatment plants in Madrid's metropolitan area and a comprehensive monitoring program should be implemented.