Marta Llorca - Academia.edu (original) (raw)

Papers by Marta Llorca

Research paper thumbnail of Perfluorinated Chemicals and Anogenital Distance: Preliminary Approach

Perfluorinated Chemicals and Anogenital Distance: Preliminary Approach

Background and aims: Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) are man-made, ... more Background and aims: Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) are man-made, widespread persistent organic pollutants. Although they have been related to deleterious effects tow...

Research paper thumbnail of Environmental risks of sewage sludge reuse in agriculture

Environmental risks of sewage sludge reuse in agriculture

Wastewater Treatment and Reuse – Lessons Learned in Technological Developments and Management Issues, 2020

Research paper thumbnail of Current Insights into Potential Effects of Micro-Nanoplastics on Human Health by in-vitro Tests

Frontiers in Toxicology, 2021

Humans are exposed to micro and nanoplastics (MNPLs) through inhalation, ingestion and, to a less... more Humans are exposed to micro and nanoplastics (MNPLs) through inhalation, ingestion and, to a lesser extent, dermal contact. In recent years, new insights indicate the potential of MNPLs to cause damages to human health. Particle toxicity can include oxidative stress, inflammatory lesions, and then increased internalization or translocation through tissues. On the other hand, plastic additives are used in plastic particles, once internalized, can release toxic substances. It is noteworthy that the potential effects of MNPLs encompass a wide range of polymers and chemical additives, showing various physicochemical and toxicological properties, and the size, shape and surface properties are other variables influencing their effects. In spite of the research carried out recently, MNPLs research is in its early stages, and further investigation is required. In this review article, the knowledge of human exposure routes and the recent results on the toxicological effects of MNPLs in human...

Research paper thumbnail of Adsorption and Desorption Behaviour of Polychlorinated Biphenyls onto Microplastics’ Surfaces in Water/Sediment Systems

Toxics, 2020

The potential of microplastics (MPLs) in marine ecosystems to adsorb and transport other micropol... more The potential of microplastics (MPLs) in marine ecosystems to adsorb and transport other micropollutants to biota, contributing to their entry in the food chain, is a primary cause of concern. However, these interactions remain poorly understood. Here, we have evaluated the adsorption/desorption behaviour of marker polychlorinated biphenyls (PCBs), onto MPL surfaces of three widely used polymers—polystyrene (PS), polyethylene (PE), and polyethylene terephthalate (PET). The range of MPL sizes ranged from 1 to 600 μm. The adsorption/desorption was evaluated in sediment/water systems in marine microcosms emulating realistic environmental conditions for 21 days. The adsorption percentages ranged from 20 to 60%. PCBs with a lower degree of chlorination showed higher adsorption percentages because of conformational impediments of PCBs with high-degree chlorination, and also by their affinity to be adsorbed in sediments. Glassy plastic polymers as PET and PS showed a superior affinity for ...

Research paper thumbnail of Microplastics in Mediterranean coastal area: toxicity and impact for the environment and human health

Trends in Environmental Analytical Chemistry, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Research paper thumbnail of Metabolic Responses of Mytilus galloprovincialis to Fullerenes in Mesocosm Exposure Experiments

Environmental Science & Technology, 2018

In this study, Mediterranean mussels (Mytilus galloprovincialis) were exposed through the diet to... more In this study, Mediterranean mussels (Mytilus galloprovincialis) were exposed through the diet to fullerene soot, at three concentrations in parallel to a control group. Their metabolomics response was assessed by high-performance liquid chromatography coupled to high-resolution mass spectrometry (HPLC-HRMS). The experiments were conducted in marine mesocosms, during 35 days (7 days of acclimatization, 21 days of exposure and 7 seven days of depuration). Real conditions were emulated in terms of physicochemical conditions of the habitat. Results confirmed the bioaccumulation of fullerenes, and the metabolome of the exposed organisms revealed significant differences in the concentrations of seven free amino acids when compared to the control group. An increase in small nonpolar amino acids (e.g. alanine) and branched chain amino acids (leucine and isoleucine) were observed. Also, glutamine concentrations decreased significantly, suggesting the activation of facultative anaerobic energy metabolism. Branched chain amino acids, such as leucine and isoleucine, followed the opposite trend after the highest level of exposure, which can imply hormesis effects. Other significant differences were observed on lipids content, such as the general increase of free fatty acids, i.e. long chain fatty acids (lauric, myristic and palmitic acids) when increasing the concentration of exposure. These results were consistent with hypoxia and oxidative stress.

Research paper thumbnail of Levels of regulated POPs in fish samples from the Sava River Basin. Comparison to legislated quality standard values

Science of The Total Environment, 2019

PCBs exceeded the maximum levels for fish (as food product) in 20% of the samples. • PBDE concent... more PCBs exceeded the maximum levels for fish (as food product) in 20% of the samples. • PBDE concentrations exceed the EQS up to more than a thousand times. • Data suggest that anthropogenic impact is observed in the Sava River Basin.

Research paper thumbnail of Fungal treatment for the removal of endocrine disrupting compounds from reverse osmosis concentrate: Identification and monitoring of transformation products of benzotriazoles

Chemosphere, 2017

The removal of 27 endocrine-disrupting compounds and related compounds (suspect effect) from a re... more The removal of 27 endocrine-disrupting compounds and related compounds (suspect effect) from a reverse osmosis concentrate using an alternative decontamination method based on a fungal treatment involving Trametes versicolor was assessed. In addition to chemical analysis, the toxicity of the treated water during the treatment was monitored using a bioluminescence inhibition test and estrogenic and anti-estrogenic tests. The compounds 1H-benzotriazole (BTZ) and two tolyltriazoles (TTZs), 4-methyl-1Hbenzotriazole (4-MBTZ) and 5-methyl-1H-benzotriazole (5-MBTZ), were present in the reverse osmosis concentrate at the highest concentrations (7.4 and 12.8 µg L-1 , respectively) and were partially removed by the fungal treatment under sterile conditions (58% for BTZ and 92% for TTZs) and non-sterile conditions, although to lesser extents (32% for BTZ and 50% for TTZs) Individual biotransformation studies of BTZ and the TTZs by T. versicolor in a synthetic medium and further analysis via on-line turbulent flow chromatography coupled to an HRMS-Orbitrap allowed the tentative identification of the transformation products (TPs). Six TPs were postulated for BTZ, two TPs were postulated for 4-MBTZ, and four TPs were postulated for 5-MBTZ. Most of these TPs are suggested to have been generated by conjugation with some sugars and via the methylation of the triazole group. Only TP 148 A, postulated to be derived from the biotransformation of BTZ, was observed in the effluent of the bioreactor treating the reverse osmosis concentrate.

Research paper thumbnail of Suspect screening of emerging pollutants and their major transformation products in wastewaters treated with fungi by liquid chromatography coupled to a high resolution mass spectrometry

Suspect screening of emerging pollutants and their major transformation products in wastewaters treated with fungi by liquid chromatography coupled to a high resolution mass spectrometry

Journal of Chromatography A, 2016

A new approach for the screening of 33 pharmaceuticals and 113 of their known transformation prod... more A new approach for the screening of 33 pharmaceuticals and 113 of their known transformation products in wastewaters was developed. The methodology is based on the analysis of samples by liquid chromatography coupled to high resolution mass spectrometry (HRMS) followed by data processing using specific software and manual confirmation. A home-made library was built with the transformation products reported in literature for the target pharmaceuticals after treatment with various fungi. The method was applied to the search of these contaminants in 67 samples generated along treatment of wastewaters with white-rot fungus Trametes versicolor. The screening methodology allowed the detection of different transformation products (TPs) generated from degradation of parent compounds after fungal treatment. This approach can be a useful tool for the rapid screening and tentative detection of emerging contaminants during water treatment in both full and batch-scale studies when pure standards are not available.

Research paper thumbnail of Photolysis of the antidepressants amisulpride and desipramine in wastewaters: Identification of transformation products formed and their fate

The Science of the total environment, Jan 8, 2015

Attenuation of pharmaceuticals due to natural sunlight is expected to be an important removal pat... more Attenuation of pharmaceuticals due to natural sunlight is expected to be an important removal pathway in wastewater treatment plants using treatment lagoon systems. In this work, the photolysis of two antidepressants, amisulpride and desipramine, has been investigated in both ultrapure water and wastewater under simulated solar irradiation. Results showed that for amisulpride short irradiation times (t1/2 approximately 3h in pure water and 4h in wastewater) were adequate to degrade the parent compound while a longer exposure period was required for desipramine (t1/2 of approximately 36h in pure water), although its degradation is enhanced almost three times by indirect photolysis in wastewaters. A significant number of transformation products (TPs) were identified for both pharmaceuticals by high-resolution mass spectrometry. In general, TPs formed are not persistent although acute toxicity tests for desipramine and its TPs showed an increase of the mixture toxicity after solar irra...

Research paper thumbnail of Identification of new transformation products during enzymatic treatment of tetracycline and erythromycin antibiotics at laboratory scale by an on-line turbulent flow liquid-chromatography coupled to a high resolution mass spectrometer LTQ-Orbitrap

Chemosphere, 2015

This work describes the formation of transformation products (TPs) by the enzymatic degradation a... more This work describes the formation of transformation products (TPs) by the enzymatic degradation at laboratory scale of two highly consumed antibiotics: tetracycline (Tc) and erythromycin (ERY). The analysis of the samples was carried out by a fast and simple method based on the novel configuration of the on-line turbulent flow system coupled to a hybrid linear ion trap-high resolution mass spectrometer. The method was optimized and validated for the complete analysis of ERY, Tc and their transformation products within 10 min without any other sample manipulation. Furthermore, the applicability of the on-line procedure was evaluated for 25 additional antibiotics, covering a wide range of chemical classes in different environmental waters with satisfactory quality parameters. Degradation rates obtained for Tc by laccase enzyme and ERY by EreB esterase enzyme without the presence of mediators were ~78% and ~50%, respectively. Concerning the identification of TPs, three suspected compounds for Tc and five of ERY have been proposed. In the case of Tc, the tentative molecular formulas with errors mass within 2 ppm have been based on the hypothesis of dehydroxylation, (bi)demethylation and oxidation of the rings A and C as major reactions. In contrast, the major TP detected for ERY has been identified as the "dehydration ERY-A", with the same molecular formula of its parent compound. In addition, the evaluation of the antibiotic activity of the samples along the enzymatic treatments showed a decrease around 100% in both cases.

Research paper thumbnail of Assessment of perfluoroalkyl substances in food items at global scale

Assessment of perfluoroalkyl substances in food items at global scale

Environmental Research, 2014

This study assessed the levels of 21 perfluoroalkyl substances (PFASs) in 283 food items (38 from... more This study assessed the levels of 21 perfluoroalkyl substances (PFASs) in 283 food items (38 from Brazil, 35 from Saudi Arabia, 174 from Spain and 36 from Serbia) among the most widely consumed foodstuffs in these geographical areas. These countries were chosen as representatives of the diet in South America, Western Asia, Mediterranean countries and South-Eastern Europe. The analysis of foodstuffs was carried out by turbulent flow chromatography (TFC) combined with liquid chromatography with triple quadrupole mass spectrometry (LC-QqQ-MS) using electrospray ionization (ESI) in negative mode. The analytical method was validated for the analysis of different foodstuff classes (cereals, fish, fruit, milk, ready-to-eat foods, oil and meat). The analytical parameters of the method fulfill the requirements specified in the Commission Recommendation 2010/161/EU. Recovery rates were in the range between 70% and 120%. For all the selected matrices, the method limits of detection (MLOD) and the method limits of quantification (MLOQ) were in the range of 5 to 650 pg/g and 17 to 2000 pg/g, respectively. In general trends, the concentrations of PFASs were in the pg/g or pg/mL levels. The more frequently detected compounds were perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA). The prevalence of the eight-carbon chain compounds in biota indicates the high stability and bioaccumulation potential of these compounds. But, at the same time, the high frequency of the shorter chain compounds is also an indication of the use of replacement compounds in the new fluorinated materials. When comparing the compounds profile and their relative abundances in the samples from diverse origin, differences were identified. However, in absolute amounts of total PFASs no large differences were found between the studied countries. Fish and seafood were identified as the major PFASs contributors to the diet in all the countries. The total sum of PFASs in fresh fish and seafood was in the range from the MLOQ to 28ng/g ww. According to the FAO-WHO diets composition, the daily intake (DI) of PFASs was calculated for various age and gender groups in the different diets. The total PFASs food intake was estimated to be between 2300 and 3800 ng /person per day for the different diets. Finally, the risk intake (RI) was calculated for selected relevant compounds. The results have indicated that by far in no case the tolerable daily intake (TDI) (150, 1500, 50,000, 1,000,000, 150, 1500 ng/kg body weight, for perfluorohexanesulfonate (PFHxS), fluorotelomer alcohol (FTOH), perfluorobutanesulfonic acid (PFBS), perfluorobutanoic acid (PFBA), PFOS and PFOA, respectively) was exceeded.

Research paper thumbnail of Sample preservation for the analysis of antibiotics in water

This paper describes a stability study performed for 56 antibiotics belonging to 9 different grou... more This paper describes a stability study performed for 56 antibiotics belonging to 9 different groups-macrolides, tetracyclines, fluoroquinolones, quinolones, penicillins, cephalosporines, lincosamides, sulfonamides and nitroimidazole antibiotics-in purified water samples fortified with the selected compounds at 10 ng/ml. For this purpose, three different sample preservation modes were tested with the aim of avoiding biotic and abiotic degradation: i) storage at-20ºC, ii) storage at-20ºC with 0.1% of EDTA and iii) pre-concentration in a solid phase extraction cartridge (SPE), which was afterwards stored at-20ºC. Concentrations of antibiotics in the samples preserved using the different protocols were monitored after 0, 1, 2 and 12 weeks. The results showed that, for the accurate determination of all compounds they should be analysed right after sampling. However, if this is not possible, most of the antibiotics can be analysed within the 1st week after sampling and preservation at-20ºC (with or without EDTA) or in a SPE cartridges at-20ºC. Nonetheless, some antibiotics found extensively in the environment, such as sulfamethoxazole, ciprofloxacin, ofloxacin, erythromycin, azithromycin and clarithromycin exhibited low stability after 1 week preservation and, therefore, they should be analysed within this time.

Research paper thumbnail of Characterization of metoprolol biodegradation and its transformation products generated in activated sludge batch experiments and in full scale WWTPs

Characterization of metoprolol biodegradation and its transformation products generated in activated sludge batch experiments and in full scale WWTPs

Metoprolol (MTP) is a compound of concern, considered as an emerging contaminant due to its high ... more Metoprolol (MTP) is a compound of concern, considered as an emerging contaminant due to its high consumption, pseudopersistence and potential ecotoxicity. Activated sludge batch experiments were performed to evaluate the biological transformation of MTP and the formation of transformation products under different treatment conditions. Total MTP removal was obtained in aerobic conditions, and the formation of MTP known metabolites (metoprolol acid (MTPA), α-hydroxymetoprolol (α-HMTP) and O-desmethylmetoprolol (O-DMTP)) and unknown transformation products (TPs) was investigated. The three known metabolites and two new TPs generated along the experiments were identified by liquid chromatography coupled to high resolution mass spectrometry. For the two new TPs plausible structures were proposed based on the tentative identification. MTPA had the major ratio formation for the TPs identified along the experiments (up to 40% of initial MTP concentration after 96 h treatment) and its persistence through biological treatment was proven. Ecotoxicity studies using Vibrio fischeri bioluminescent bacteria in an acute toxicity test showed that MTP and its known TPs are not toxic with the exception of o-DMTP. Finally, MTP and its TPs were monitored in a full scale membrane bioreactor and in a full scale conventional urban wastewater treatment plant (WWTP) and the results were compared with those obtained in batch experiments. α-HMTP was detected for the first time in a WWTP influent whereas MTPA was detected in influent and effluent WWTP samples at much higher levels (up to 100 folds higher) than MTP itself remarking its high persistence.

Research paper thumbnail of Hospital wastewater treatment by fungal bioreactor: removal efficiency for pharmaceuticals and endocrine disruptor compounds

The Science of the total environment, Jan 15, 2014

Hospital effluents contribute to the occurrence of emerging contaminants in the environment due t... more Hospital effluents contribute to the occurrence of emerging contaminants in the environment due to their high load of pharmaceutical active compounds (PhACs) and some endocrine disruptor compounds (EDCs). Nowadays, hospital wastewaters are co-treated with urban wastewater; however, the dilution factor and the inefficiency of wastewater treatment plants in the removal of PhACs and EDCs make inappropriate the co-treatment of both effluents. In this paper, a new alternative to pre-treat hospital wastewater concerning the removal of PhACs and EDCs is presented. The treatment was carried out in a batch fluidized bed bioreactor under sterile and non-sterile conditions with Trametes versicolor pellets. Results on non-sterile experiments pointed out that 46 out of the 51 detected PhACs and EDCs were partially to completely removed. The total initial PhAC amount into the bioreactor was 8185 μg in sterile treatment and 8426 μg in non-sterile treatment, and the overall load elimination was 83....

Research paper thumbnail of Organic UV filters and their photodegradates, metabolites and disinfection by-products in the aquatic environment

TrAC Trends in Analytical Chemistry, 2008

Organic ultraviolet (UV) filters are compounds used to absorb UV radiation and are increasingly b... more Organic ultraviolet (UV) filters are compounds used to absorb UV radiation and are increasingly being used as a result of growing concern about UV radiation and skin cancer. Their growing use may increase environmental contamination and exposure through the food chain. There is therefore major concern about the environmental fate and potential effect of organic UV filters used in beauty creams, hair sprays, shampoos, and other personal-care products, as well as those added to plastics and other materials to prevent degradation of polymers and pigments. This review describes the processes undergone by these compounds once released into the environment and the instrumental methods based on chromatography and mass spectrometry reported in the literature for their determination in environmental samples. We include concentrations found in the environment (e.g., water, soil, sediments, sludge and biota). The main focus is on metabolites, photodegradates and by-products of wastewater treatment.

Research paper thumbnail of Analysis of perfluoroalkyl substances in cord blood by turbulent flow chromatography coupled to tandem mass spectrometry

Analysis of perfluoroalkyl substances in cord blood by turbulent flow chromatography coupled to tandem mass spectrometry

Science of The Total Environment, 2012

A fast on-line analytical method based on turbulent flow chromatography (TFC) in combination with... more A fast on-line analytical method based on turbulent flow chromatography (TFC) in combination with tandem mass spectrometry has been applied for the first time for the analysis of eighteen perfluoroalkyl substances (PFASs), in cord blood. A simple and rapid sample pre-treatment was optimised consisting on protein precipitation of 100 μL of sample with acetonitrile (1:1) followed by centrifugation during 10 min. The method was adapted to be sensitive enough and robust with minimum sample injection volume requirements (20 μL). The optimised methodology presented method limits of detection (MLOD) between 0.031 and 0.76 μg/L, detection capabilities (CCα) in the range between 0.005 and 0.99 μg/L and decision limits (CCβ) ranging from 0.006 to 1.16 μg/L. The recoveries in blank blood were calculated by spiking experiments with a mixture of 18 PFASs and established between 70 and 126% for most of compounds. Isotopic dilution was carried out for quantification of selected analytes. In-house validation of this new approach was carried out according to the requirements in the 2002/657/EC Decision. Finally the good applicability of this new approach was proved by the analysis of 60 cord blood samples from two different Mediterranean cities, Barcelona (Spain) and Heraklion (Greece). Ions perfluorohexanesulfonate (PFHxS) and perfluorooctanesulfonate (PFOS) were found at highest concentration and the more frequently compounds were PFHxS, PFOS and perfluorooctanoic acid (PFOA). The newly developed method proved to be suitable for large-scale epidemiologic studies, and to the data on PFASs exposure during pregnancy.

Research paper thumbnail of Infant exposure of perfluorinated compounds: Levels in breast milk and commercial baby food

Infant exposure of perfluorinated compounds: Levels in breast milk and commercial baby food

Environment International, 2010

In this study, an analytical method to determine six perfluorinated compounds (PFCs) based on alk... more In this study, an analytical method to determine six perfluorinated compounds (PFCs) based on alkaline digestion and solid phase extraction (SPE) followed by liquid chromatography-quadrupole-linear ion trap mass spectrometry (LC-QqLIT-MS) was validated for the analysis of human breast milk, milk infant formulas and cereals baby food. The average recoveries of the different matrices were in general higher than 70% with a relative standard deviation (RSD) lower than 21% and method limits of detection (MLOD) ranging from 1.2 to 362 ng/L for the different compounds and matrices. The method was applied to investigate the occurrence of PFCs in 20 samples of human breast milk, and 5 samples of infant formulas and cereal baby food (3 brands of commercial milk infant formulas and 2 brands of cereals baby food). Breast milk samples were collected in 2008 from donors living in Barcelona city (Spain) on the 40 days postpartum. Perfluorooctanesulfonate (PFOS) and perfluoro-7-methyloctanoic acid (i,p-PFNA) were predominant being present in the 95% of breast milk samples. Perfluorooctanoic acid (PFOA) was quantified in 8 of the 20 breast milk samples at concentrations in the range of 21-907 ng/L. Commercial formulas and food were purchased also in 2009 from a retail store. The six PFCs were detected in all brands of milk infant formulas and cereals baby food analyzed, being perfluorodecanoic acid (PFDA), PFOS, PFOA and i,p-PFNA the compounds detected in higher concentrations (up to 1289 ng/kg). PFCs presence can be associated to possible migration from packaging and containers during production processes. Finally, based on estimated body weight and newborn intake, PFOS and PFOA daily intakes and risk indexes (RI) were estimated for the firsts 6 month of life. We found that ingestion rates of PFOS and PFOA, with exception of one breast milk sample did not exceed the tolerable daily intake (TDI) recommended by the EFSA. However, more research is needed in order to assess possible risk associated to PFCs contamination during early stages of life.

Research paper thumbnail of Perfluorinated Compounds in Food: A Global Perspective

Perfluorinated Compounds in Food: A Global Perspective

Critical Reviews in Food Science and Nutrition, 2011

Perfluorinated compounds (PFCs) are resistant to breakdown and are turning up in unexpected place... more Perfluorinated compounds (PFCs) are resistant to breakdown and are turning up in unexpected places around the world, becoming emerging food contaminants. Although these chemicals have been used in countless products since the 1950s, they have been subject to little control until now. There is still an insufficient knowledge of their sources, occurrence, and hazards for food safety decision making. This article provides a comprehensive review of the food contamination levels and dietary intake risks posed by PFCs, as well as the specific methods developed for their determination. It is based on the evaluation of the published literature between 2004 and the beginning of 2010, with special emphasis on those reports of the last two years and in the examination of the growing body of studies on the exposure assessment and food occurrence of PFCs. The current state-of-the art and future perspectives in extraction, clean-up, detection, identification, confirmation, and quantification highlighting the advantages and limitations of each technique have been summarized. How much is known about the sources and pathways of food web and human exposure, which is needed to control and manage the release of these emerging toxic contaminants, has also been explained.

Research paper thumbnail of Wastewater reuse in Mediterranean semi-arid areas: The impact of discharges of tertiary treated sewage on the load of polar micro pollutants in the Llobregat river (NE Spain)

Chemosphere, 2011

The presence of sewage-borne micro contaminants in environmental waters is directly related to th... more The presence of sewage-borne micro contaminants in environmental waters is directly related to the discharge of treated effluents from wastewater treatment plants (WWTP) and the flow rate of the receiving river waters. Mediterranean rivers, in particular, are characterized by important fluctuations in the flow rates and heavy pollution pressures resulting from extensive urban, industrial and agricultural activities. This translates into contamination levels in these rivers often higher than those in other larger European basins. The present work provides an overview of the occurrence of five groups of organic contaminants (131 compounds) namely pharmaceuticals, illicit drugs, polar pesticides, estrogens, alkylphenols and related ethoxylates in WWTP tertiary treatment effluents. Data gathered during a period of water reuse carried out in the lower stretch of the Llobregat river (NE Spain), in the surroundings of the town of Barcelona as a consequence of the severe drought that took place along the years 2007-2008 are presented as illustrative example. In general, measured concentrations of the target compounds were in the low to mid ng L À1 range. The total concentration of each compound class downstream to the discharge point was similar or slightly higher than that found upstream. Regarding the loads calculated for each compound, the relative contribution from the river upstream and the tertiary effluent were highly compound depending with no apparent trend. However, estimation of the overall bulk loads for each compound class determined in the Llobregat river showed the following rank order: pharmaceuticals > alkylphenols > pesticides > illicit drugs) estrogens.

Research paper thumbnail of Perfluorinated Chemicals and Anogenital Distance: Preliminary Approach

Perfluorinated Chemicals and Anogenital Distance: Preliminary Approach

Background and aims: Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) are man-made, ... more Background and aims: Perfluorooctanesulfonate (PFOS) and perfluorooctanoate (PFOA) are man-made, widespread persistent organic pollutants. Although they have been related to deleterious effects tow...

Research paper thumbnail of Environmental risks of sewage sludge reuse in agriculture

Environmental risks of sewage sludge reuse in agriculture

Wastewater Treatment and Reuse – Lessons Learned in Technological Developments and Management Issues, 2020

Research paper thumbnail of Current Insights into Potential Effects of Micro-Nanoplastics on Human Health by in-vitro Tests

Frontiers in Toxicology, 2021

Humans are exposed to micro and nanoplastics (MNPLs) through inhalation, ingestion and, to a less... more Humans are exposed to micro and nanoplastics (MNPLs) through inhalation, ingestion and, to a lesser extent, dermal contact. In recent years, new insights indicate the potential of MNPLs to cause damages to human health. Particle toxicity can include oxidative stress, inflammatory lesions, and then increased internalization or translocation through tissues. On the other hand, plastic additives are used in plastic particles, once internalized, can release toxic substances. It is noteworthy that the potential effects of MNPLs encompass a wide range of polymers and chemical additives, showing various physicochemical and toxicological properties, and the size, shape and surface properties are other variables influencing their effects. In spite of the research carried out recently, MNPLs research is in its early stages, and further investigation is required. In this review article, the knowledge of human exposure routes and the recent results on the toxicological effects of MNPLs in human...

Research paper thumbnail of Adsorption and Desorption Behaviour of Polychlorinated Biphenyls onto Microplastics’ Surfaces in Water/Sediment Systems

Toxics, 2020

The potential of microplastics (MPLs) in marine ecosystems to adsorb and transport other micropol... more The potential of microplastics (MPLs) in marine ecosystems to adsorb and transport other micropollutants to biota, contributing to their entry in the food chain, is a primary cause of concern. However, these interactions remain poorly understood. Here, we have evaluated the adsorption/desorption behaviour of marker polychlorinated biphenyls (PCBs), onto MPL surfaces of three widely used polymers—polystyrene (PS), polyethylene (PE), and polyethylene terephthalate (PET). The range of MPL sizes ranged from 1 to 600 μm. The adsorption/desorption was evaluated in sediment/water systems in marine microcosms emulating realistic environmental conditions for 21 days. The adsorption percentages ranged from 20 to 60%. PCBs with a lower degree of chlorination showed higher adsorption percentages because of conformational impediments of PCBs with high-degree chlorination, and also by their affinity to be adsorbed in sediments. Glassy plastic polymers as PET and PS showed a superior affinity for ...

Research paper thumbnail of Microplastics in Mediterranean coastal area: toxicity and impact for the environment and human health

Trends in Environmental Analytical Chemistry, 2020

This is a PDF file of an article that has undergone enhancements after acceptance, such as the ad... more This is a PDF file of an article that has undergone enhancements after acceptance, such as the addition of a cover page and metadata, and formatting for readability, but it is not yet the definitive version of record. This version will undergo additional copyediting, typesetting and review before it is published in its final form, but we are providing this version to give early visibility of the article. Please note that, during the production process, errors may be discovered which could affect the content, and all legal disclaimers that apply to the journal pertain.

Research paper thumbnail of Metabolic Responses of Mytilus galloprovincialis to Fullerenes in Mesocosm Exposure Experiments

Environmental Science & Technology, 2018

In this study, Mediterranean mussels (Mytilus galloprovincialis) were exposed through the diet to... more In this study, Mediterranean mussels (Mytilus galloprovincialis) were exposed through the diet to fullerene soot, at three concentrations in parallel to a control group. Their metabolomics response was assessed by high-performance liquid chromatography coupled to high-resolution mass spectrometry (HPLC-HRMS). The experiments were conducted in marine mesocosms, during 35 days (7 days of acclimatization, 21 days of exposure and 7 seven days of depuration). Real conditions were emulated in terms of physicochemical conditions of the habitat. Results confirmed the bioaccumulation of fullerenes, and the metabolome of the exposed organisms revealed significant differences in the concentrations of seven free amino acids when compared to the control group. An increase in small nonpolar amino acids (e.g. alanine) and branched chain amino acids (leucine and isoleucine) were observed. Also, glutamine concentrations decreased significantly, suggesting the activation of facultative anaerobic energy metabolism. Branched chain amino acids, such as leucine and isoleucine, followed the opposite trend after the highest level of exposure, which can imply hormesis effects. Other significant differences were observed on lipids content, such as the general increase of free fatty acids, i.e. long chain fatty acids (lauric, myristic and palmitic acids) when increasing the concentration of exposure. These results were consistent with hypoxia and oxidative stress.

Research paper thumbnail of Levels of regulated POPs in fish samples from the Sava River Basin. Comparison to legislated quality standard values

Science of The Total Environment, 2019

PCBs exceeded the maximum levels for fish (as food product) in 20% of the samples. • PBDE concent... more PCBs exceeded the maximum levels for fish (as food product) in 20% of the samples. • PBDE concentrations exceed the EQS up to more than a thousand times. • Data suggest that anthropogenic impact is observed in the Sava River Basin.

Research paper thumbnail of Fungal treatment for the removal of endocrine disrupting compounds from reverse osmosis concentrate: Identification and monitoring of transformation products of benzotriazoles

Chemosphere, 2017

The removal of 27 endocrine-disrupting compounds and related compounds (suspect effect) from a re... more The removal of 27 endocrine-disrupting compounds and related compounds (suspect effect) from a reverse osmosis concentrate using an alternative decontamination method based on a fungal treatment involving Trametes versicolor was assessed. In addition to chemical analysis, the toxicity of the treated water during the treatment was monitored using a bioluminescence inhibition test and estrogenic and anti-estrogenic tests. The compounds 1H-benzotriazole (BTZ) and two tolyltriazoles (TTZs), 4-methyl-1Hbenzotriazole (4-MBTZ) and 5-methyl-1H-benzotriazole (5-MBTZ), were present in the reverse osmosis concentrate at the highest concentrations (7.4 and 12.8 µg L-1 , respectively) and were partially removed by the fungal treatment under sterile conditions (58% for BTZ and 92% for TTZs) and non-sterile conditions, although to lesser extents (32% for BTZ and 50% for TTZs) Individual biotransformation studies of BTZ and the TTZs by T. versicolor in a synthetic medium and further analysis via on-line turbulent flow chromatography coupled to an HRMS-Orbitrap allowed the tentative identification of the transformation products (TPs). Six TPs were postulated for BTZ, two TPs were postulated for 4-MBTZ, and four TPs were postulated for 5-MBTZ. Most of these TPs are suggested to have been generated by conjugation with some sugars and via the methylation of the triazole group. Only TP 148 A, postulated to be derived from the biotransformation of BTZ, was observed in the effluent of the bioreactor treating the reverse osmosis concentrate.

Research paper thumbnail of Suspect screening of emerging pollutants and their major transformation products in wastewaters treated with fungi by liquid chromatography coupled to a high resolution mass spectrometry

Suspect screening of emerging pollutants and their major transformation products in wastewaters treated with fungi by liquid chromatography coupled to a high resolution mass spectrometry

Journal of Chromatography A, 2016

A new approach for the screening of 33 pharmaceuticals and 113 of their known transformation prod... more A new approach for the screening of 33 pharmaceuticals and 113 of their known transformation products in wastewaters was developed. The methodology is based on the analysis of samples by liquid chromatography coupled to high resolution mass spectrometry (HRMS) followed by data processing using specific software and manual confirmation. A home-made library was built with the transformation products reported in literature for the target pharmaceuticals after treatment with various fungi. The method was applied to the search of these contaminants in 67 samples generated along treatment of wastewaters with white-rot fungus Trametes versicolor. The screening methodology allowed the detection of different transformation products (TPs) generated from degradation of parent compounds after fungal treatment. This approach can be a useful tool for the rapid screening and tentative detection of emerging contaminants during water treatment in both full and batch-scale studies when pure standards are not available.

Research paper thumbnail of Photolysis of the antidepressants amisulpride and desipramine in wastewaters: Identification of transformation products formed and their fate

The Science of the total environment, Jan 8, 2015

Attenuation of pharmaceuticals due to natural sunlight is expected to be an important removal pat... more Attenuation of pharmaceuticals due to natural sunlight is expected to be an important removal pathway in wastewater treatment plants using treatment lagoon systems. In this work, the photolysis of two antidepressants, amisulpride and desipramine, has been investigated in both ultrapure water and wastewater under simulated solar irradiation. Results showed that for amisulpride short irradiation times (t1/2 approximately 3h in pure water and 4h in wastewater) were adequate to degrade the parent compound while a longer exposure period was required for desipramine (t1/2 of approximately 36h in pure water), although its degradation is enhanced almost three times by indirect photolysis in wastewaters. A significant number of transformation products (TPs) were identified for both pharmaceuticals by high-resolution mass spectrometry. In general, TPs formed are not persistent although acute toxicity tests for desipramine and its TPs showed an increase of the mixture toxicity after solar irra...

Research paper thumbnail of Identification of new transformation products during enzymatic treatment of tetracycline and erythromycin antibiotics at laboratory scale by an on-line turbulent flow liquid-chromatography coupled to a high resolution mass spectrometer LTQ-Orbitrap

Chemosphere, 2015

This work describes the formation of transformation products (TPs) by the enzymatic degradation a... more This work describes the formation of transformation products (TPs) by the enzymatic degradation at laboratory scale of two highly consumed antibiotics: tetracycline (Tc) and erythromycin (ERY). The analysis of the samples was carried out by a fast and simple method based on the novel configuration of the on-line turbulent flow system coupled to a hybrid linear ion trap-high resolution mass spectrometer. The method was optimized and validated for the complete analysis of ERY, Tc and their transformation products within 10 min without any other sample manipulation. Furthermore, the applicability of the on-line procedure was evaluated for 25 additional antibiotics, covering a wide range of chemical classes in different environmental waters with satisfactory quality parameters. Degradation rates obtained for Tc by laccase enzyme and ERY by EreB esterase enzyme without the presence of mediators were ~78% and ~50%, respectively. Concerning the identification of TPs, three suspected compounds for Tc and five of ERY have been proposed. In the case of Tc, the tentative molecular formulas with errors mass within 2 ppm have been based on the hypothesis of dehydroxylation, (bi)demethylation and oxidation of the rings A and C as major reactions. In contrast, the major TP detected for ERY has been identified as the "dehydration ERY-A", with the same molecular formula of its parent compound. In addition, the evaluation of the antibiotic activity of the samples along the enzymatic treatments showed a decrease around 100% in both cases.

Research paper thumbnail of Assessment of perfluoroalkyl substances in food items at global scale

Assessment of perfluoroalkyl substances in food items at global scale

Environmental Research, 2014

This study assessed the levels of 21 perfluoroalkyl substances (PFASs) in 283 food items (38 from... more This study assessed the levels of 21 perfluoroalkyl substances (PFASs) in 283 food items (38 from Brazil, 35 from Saudi Arabia, 174 from Spain and 36 from Serbia) among the most widely consumed foodstuffs in these geographical areas. These countries were chosen as representatives of the diet in South America, Western Asia, Mediterranean countries and South-Eastern Europe. The analysis of foodstuffs was carried out by turbulent flow chromatography (TFC) combined with liquid chromatography with triple quadrupole mass spectrometry (LC-QqQ-MS) using electrospray ionization (ESI) in negative mode. The analytical method was validated for the analysis of different foodstuff classes (cereals, fish, fruit, milk, ready-to-eat foods, oil and meat). The analytical parameters of the method fulfill the requirements specified in the Commission Recommendation 2010/161/EU. Recovery rates were in the range between 70% and 120%. For all the selected matrices, the method limits of detection (MLOD) and the method limits of quantification (MLOQ) were in the range of 5 to 650 pg/g and 17 to 2000 pg/g, respectively. In general trends, the concentrations of PFASs were in the pg/g or pg/mL levels. The more frequently detected compounds were perfluorooctane sulfonic acid (PFOS), perfluorooctanoic acid (PFOA) and perfluorobutanoic acid (PFBA). The prevalence of the eight-carbon chain compounds in biota indicates the high stability and bioaccumulation potential of these compounds. But, at the same time, the high frequency of the shorter chain compounds is also an indication of the use of replacement compounds in the new fluorinated materials. When comparing the compounds profile and their relative abundances in the samples from diverse origin, differences were identified. However, in absolute amounts of total PFASs no large differences were found between the studied countries. Fish and seafood were identified as the major PFASs contributors to the diet in all the countries. The total sum of PFASs in fresh fish and seafood was in the range from the MLOQ to 28ng/g ww. According to the FAO-WHO diets composition, the daily intake (DI) of PFASs was calculated for various age and gender groups in the different diets. The total PFASs food intake was estimated to be between 2300 and 3800 ng /person per day for the different diets. Finally, the risk intake (RI) was calculated for selected relevant compounds. The results have indicated that by far in no case the tolerable daily intake (TDI) (150, 1500, 50,000, 1,000,000, 150, 1500 ng/kg body weight, for perfluorohexanesulfonate (PFHxS), fluorotelomer alcohol (FTOH), perfluorobutanesulfonic acid (PFBS), perfluorobutanoic acid (PFBA), PFOS and PFOA, respectively) was exceeded.

Research paper thumbnail of Sample preservation for the analysis of antibiotics in water

This paper describes a stability study performed for 56 antibiotics belonging to 9 different grou... more This paper describes a stability study performed for 56 antibiotics belonging to 9 different groups-macrolides, tetracyclines, fluoroquinolones, quinolones, penicillins, cephalosporines, lincosamides, sulfonamides and nitroimidazole antibiotics-in purified water samples fortified with the selected compounds at 10 ng/ml. For this purpose, three different sample preservation modes were tested with the aim of avoiding biotic and abiotic degradation: i) storage at-20ºC, ii) storage at-20ºC with 0.1% of EDTA and iii) pre-concentration in a solid phase extraction cartridge (SPE), which was afterwards stored at-20ºC. Concentrations of antibiotics in the samples preserved using the different protocols were monitored after 0, 1, 2 and 12 weeks. The results showed that, for the accurate determination of all compounds they should be analysed right after sampling. However, if this is not possible, most of the antibiotics can be analysed within the 1st week after sampling and preservation at-20ºC (with or without EDTA) or in a SPE cartridges at-20ºC. Nonetheless, some antibiotics found extensively in the environment, such as sulfamethoxazole, ciprofloxacin, ofloxacin, erythromycin, azithromycin and clarithromycin exhibited low stability after 1 week preservation and, therefore, they should be analysed within this time.

Research paper thumbnail of Characterization of metoprolol biodegradation and its transformation products generated in activated sludge batch experiments and in full scale WWTPs

Characterization of metoprolol biodegradation and its transformation products generated in activated sludge batch experiments and in full scale WWTPs

Metoprolol (MTP) is a compound of concern, considered as an emerging contaminant due to its high ... more Metoprolol (MTP) is a compound of concern, considered as an emerging contaminant due to its high consumption, pseudopersistence and potential ecotoxicity. Activated sludge batch experiments were performed to evaluate the biological transformation of MTP and the formation of transformation products under different treatment conditions. Total MTP removal was obtained in aerobic conditions, and the formation of MTP known metabolites (metoprolol acid (MTPA), α-hydroxymetoprolol (α-HMTP) and O-desmethylmetoprolol (O-DMTP)) and unknown transformation products (TPs) was investigated. The three known metabolites and two new TPs generated along the experiments were identified by liquid chromatography coupled to high resolution mass spectrometry. For the two new TPs plausible structures were proposed based on the tentative identification. MTPA had the major ratio formation for the TPs identified along the experiments (up to 40% of initial MTP concentration after 96 h treatment) and its persistence through biological treatment was proven. Ecotoxicity studies using Vibrio fischeri bioluminescent bacteria in an acute toxicity test showed that MTP and its known TPs are not toxic with the exception of o-DMTP. Finally, MTP and its TPs were monitored in a full scale membrane bioreactor and in a full scale conventional urban wastewater treatment plant (WWTP) and the results were compared with those obtained in batch experiments. α-HMTP was detected for the first time in a WWTP influent whereas MTPA was detected in influent and effluent WWTP samples at much higher levels (up to 100 folds higher) than MTP itself remarking its high persistence.

Research paper thumbnail of Hospital wastewater treatment by fungal bioreactor: removal efficiency for pharmaceuticals and endocrine disruptor compounds

The Science of the total environment, Jan 15, 2014

Hospital effluents contribute to the occurrence of emerging contaminants in the environment due t... more Hospital effluents contribute to the occurrence of emerging contaminants in the environment due to their high load of pharmaceutical active compounds (PhACs) and some endocrine disruptor compounds (EDCs). Nowadays, hospital wastewaters are co-treated with urban wastewater; however, the dilution factor and the inefficiency of wastewater treatment plants in the removal of PhACs and EDCs make inappropriate the co-treatment of both effluents. In this paper, a new alternative to pre-treat hospital wastewater concerning the removal of PhACs and EDCs is presented. The treatment was carried out in a batch fluidized bed bioreactor under sterile and non-sterile conditions with Trametes versicolor pellets. Results on non-sterile experiments pointed out that 46 out of the 51 detected PhACs and EDCs were partially to completely removed. The total initial PhAC amount into the bioreactor was 8185 μg in sterile treatment and 8426 μg in non-sterile treatment, and the overall load elimination was 83....

Research paper thumbnail of Organic UV filters and their photodegradates, metabolites and disinfection by-products in the aquatic environment

TrAC Trends in Analytical Chemistry, 2008

Organic ultraviolet (UV) filters are compounds used to absorb UV radiation and are increasingly b... more Organic ultraviolet (UV) filters are compounds used to absorb UV radiation and are increasingly being used as a result of growing concern about UV radiation and skin cancer. Their growing use may increase environmental contamination and exposure through the food chain. There is therefore major concern about the environmental fate and potential effect of organic UV filters used in beauty creams, hair sprays, shampoos, and other personal-care products, as well as those added to plastics and other materials to prevent degradation of polymers and pigments. This review describes the processes undergone by these compounds once released into the environment and the instrumental methods based on chromatography and mass spectrometry reported in the literature for their determination in environmental samples. We include concentrations found in the environment (e.g., water, soil, sediments, sludge and biota). The main focus is on metabolites, photodegradates and by-products of wastewater treatment.

Research paper thumbnail of Analysis of perfluoroalkyl substances in cord blood by turbulent flow chromatography coupled to tandem mass spectrometry

Analysis of perfluoroalkyl substances in cord blood by turbulent flow chromatography coupled to tandem mass spectrometry

Science of The Total Environment, 2012

A fast on-line analytical method based on turbulent flow chromatography (TFC) in combination with... more A fast on-line analytical method based on turbulent flow chromatography (TFC) in combination with tandem mass spectrometry has been applied for the first time for the analysis of eighteen perfluoroalkyl substances (PFASs), in cord blood. A simple and rapid sample pre-treatment was optimised consisting on protein precipitation of 100 μL of sample with acetonitrile (1:1) followed by centrifugation during 10 min. The method was adapted to be sensitive enough and robust with minimum sample injection volume requirements (20 μL). The optimised methodology presented method limits of detection (MLOD) between 0.031 and 0.76 μg/L, detection capabilities (CCα) in the range between 0.005 and 0.99 μg/L and decision limits (CCβ) ranging from 0.006 to 1.16 μg/L. The recoveries in blank blood were calculated by spiking experiments with a mixture of 18 PFASs and established between 70 and 126% for most of compounds. Isotopic dilution was carried out for quantification of selected analytes. In-house validation of this new approach was carried out according to the requirements in the 2002/657/EC Decision. Finally the good applicability of this new approach was proved by the analysis of 60 cord blood samples from two different Mediterranean cities, Barcelona (Spain) and Heraklion (Greece). Ions perfluorohexanesulfonate (PFHxS) and perfluorooctanesulfonate (PFOS) were found at highest concentration and the more frequently compounds were PFHxS, PFOS and perfluorooctanoic acid (PFOA). The newly developed method proved to be suitable for large-scale epidemiologic studies, and to the data on PFASs exposure during pregnancy.

Research paper thumbnail of Infant exposure of perfluorinated compounds: Levels in breast milk and commercial baby food

Infant exposure of perfluorinated compounds: Levels in breast milk and commercial baby food

Environment International, 2010

In this study, an analytical method to determine six perfluorinated compounds (PFCs) based on alk... more In this study, an analytical method to determine six perfluorinated compounds (PFCs) based on alkaline digestion and solid phase extraction (SPE) followed by liquid chromatography-quadrupole-linear ion trap mass spectrometry (LC-QqLIT-MS) was validated for the analysis of human breast milk, milk infant formulas and cereals baby food. The average recoveries of the different matrices were in general higher than 70% with a relative standard deviation (RSD) lower than 21% and method limits of detection (MLOD) ranging from 1.2 to 362 ng/L for the different compounds and matrices. The method was applied to investigate the occurrence of PFCs in 20 samples of human breast milk, and 5 samples of infant formulas and cereal baby food (3 brands of commercial milk infant formulas and 2 brands of cereals baby food). Breast milk samples were collected in 2008 from donors living in Barcelona city (Spain) on the 40 days postpartum. Perfluorooctanesulfonate (PFOS) and perfluoro-7-methyloctanoic acid (i,p-PFNA) were predominant being present in the 95% of breast milk samples. Perfluorooctanoic acid (PFOA) was quantified in 8 of the 20 breast milk samples at concentrations in the range of 21-907 ng/L. Commercial formulas and food were purchased also in 2009 from a retail store. The six PFCs were detected in all brands of milk infant formulas and cereals baby food analyzed, being perfluorodecanoic acid (PFDA), PFOS, PFOA and i,p-PFNA the compounds detected in higher concentrations (up to 1289 ng/kg). PFCs presence can be associated to possible migration from packaging and containers during production processes. Finally, based on estimated body weight and newborn intake, PFOS and PFOA daily intakes and risk indexes (RI) were estimated for the firsts 6 month of life. We found that ingestion rates of PFOS and PFOA, with exception of one breast milk sample did not exceed the tolerable daily intake (TDI) recommended by the EFSA. However, more research is needed in order to assess possible risk associated to PFCs contamination during early stages of life.

Research paper thumbnail of Perfluorinated Compounds in Food: A Global Perspective

Perfluorinated Compounds in Food: A Global Perspective

Critical Reviews in Food Science and Nutrition, 2011

Perfluorinated compounds (PFCs) are resistant to breakdown and are turning up in unexpected place... more Perfluorinated compounds (PFCs) are resistant to breakdown and are turning up in unexpected places around the world, becoming emerging food contaminants. Although these chemicals have been used in countless products since the 1950s, they have been subject to little control until now. There is still an insufficient knowledge of their sources, occurrence, and hazards for food safety decision making. This article provides a comprehensive review of the food contamination levels and dietary intake risks posed by PFCs, as well as the specific methods developed for their determination. It is based on the evaluation of the published literature between 2004 and the beginning of 2010, with special emphasis on those reports of the last two years and in the examination of the growing body of studies on the exposure assessment and food occurrence of PFCs. The current state-of-the art and future perspectives in extraction, clean-up, detection, identification, confirmation, and quantification highlighting the advantages and limitations of each technique have been summarized. How much is known about the sources and pathways of food web and human exposure, which is needed to control and manage the release of these emerging toxic contaminants, has also been explained.

Research paper thumbnail of Wastewater reuse in Mediterranean semi-arid areas: The impact of discharges of tertiary treated sewage on the load of polar micro pollutants in the Llobregat river (NE Spain)

Chemosphere, 2011

The presence of sewage-borne micro contaminants in environmental waters is directly related to th... more The presence of sewage-borne micro contaminants in environmental waters is directly related to the discharge of treated effluents from wastewater treatment plants (WWTP) and the flow rate of the receiving river waters. Mediterranean rivers, in particular, are characterized by important fluctuations in the flow rates and heavy pollution pressures resulting from extensive urban, industrial and agricultural activities. This translates into contamination levels in these rivers often higher than those in other larger European basins. The present work provides an overview of the occurrence of five groups of organic contaminants (131 compounds) namely pharmaceuticals, illicit drugs, polar pesticides, estrogens, alkylphenols and related ethoxylates in WWTP tertiary treatment effluents. Data gathered during a period of water reuse carried out in the lower stretch of the Llobregat river (NE Spain), in the surroundings of the town of Barcelona as a consequence of the severe drought that took place along the years 2007-2008 are presented as illustrative example. In general, measured concentrations of the target compounds were in the low to mid ng L À1 range. The total concentration of each compound class downstream to the discharge point was similar or slightly higher than that found upstream. Regarding the loads calculated for each compound, the relative contribution from the river upstream and the tertiary effluent were highly compound depending with no apparent trend. However, estimation of the overall bulk loads for each compound class determined in the Llobregat river showed the following rank order: pharmaceuticals > alkylphenols > pesticides > illicit drugs) estrogens.