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Coronavirus disease 2019; First trimester; Preeclampsia Coronavirus 2019; Primer trimestre; Preeclàmpsia Coronavirus 2019; Primer trimestre; Preeclampsia Introduction: The association between preeclampsia and coronavirus disease 2019 (COVID-19) is under study. Previous publications have hypothesized the existence of shared risk factors for both conditions or a deficient trophoblastic invasion as possible explanations for this association. The primary aim of this study was to examine baseline risk factors measured in the first-trimester combined screening for preeclampsia in pregnant women with COVID-19 compared with the general population. A secondary aim of this study was to compare risk factors among patients with mild and severe COVID-19. Material and methods: This was an observational retrospective study conducted at Vall d'Hebron Hospital Campus (Catalonia, Spain). Study patients were 231 pregnant women undergoing the first-trimester screening for preeclampsia and positive for severe acute respiratory syndrome coronavirus 2 between February 2020 and September 2021. The reference cohort were 13 033 women of the general population from six centers across Catalonia from May 2019 to June 2021. Based on the need for hospitalization, patients were classified in two groups: mild and severe COVID-19. First-trimester screening for preeclampsia included maternal history, mean arterial blood pressure, mean uterine artery pulsatility index (UtAPI), placental growth factor (PlGF), and pregnancy-associated plasma protein-A (PAPP-A). Results: The proportion of cases at high risk for preeclampsia was significantly higher among the COVID-19 group compared with the general population (19.0% and 13.2%, respectively; p = 0.012). When analyzing risk factors for preeclampsia individually, women with COVID-19 had higher median body mass index (25.2 vs 24.5, p = 0.041), higher UtAPI multiple of the median (MoM) (1.08 vs 1.00, p < 0.001), higher incidence of chronic hypertension (2.8% vs 0.9%, p = 0.015), and there were fewer smokers (5.7% vs 11.6%, p = 0.007). The MoMs of PlGF and PAPP-A did not differ significantly between both groups (0.96 vs 0.97, p = 0.760 and 1.00 vs 1.01, p = 0.432; respectively). Conclusions: In patients with COVID-19, there was a higher proportion of women at high risk for preeclampsia at the first-trimester screening than in the general population, mainly because of maternal risk factors, rather than placental signs of a deficient trophoblastic invasion.

Objective: To examine baseline risk factors measured in the first-trimester screening for preeclampsia (PE) in pregnant women with COVID-19 versus the general population. To compare risk factors among patients with mild and severe COVID-19. Design: Observational retrospective study. Setting: Six maternities in Catalonia. Population: Study patients were 231 pregnant women undergoing first-trimester screening for PE and positive for SARS-CoV-2. Reference cohort were 13,033 pregnant women with first-trimester screening for PE from 6 maternities. Methods: Recording of maternal history, mean arterial blood pressure (MAP), mean uterine artery pulsatility index (UtAPI), placental growth factor (PlGF) and pregnancy-associated plasma protein-A at first trimester. Confirmation of SARS-CoV-2 infection. Based on the need for hospitalization, patients were classified into mild and severe COVID-19. Main outcome measures: Comparison of proportion of cases at a high risk for PE and of risk factors for PE among groups. Results: High risk for PE was significantly higher amongst COVID-19 patients compared to the general population, showing higher rates of obesity, chronic hypertension, higher UtAPI, and lower rates of smokers. PlGF did not differ significantly. In women with severe COVID-19, compared with mild COVID-19, BMI and MAP were significantly higher, whereas PlGF and UtAPI did not differ significantly. Conclusions: In patients with COVID-19 there was a higher proportion of women at a high risk for PE than in the general population, mainly due to maternal risk factors, rather than placental signs of a deficient trophoblastic invasion. Likewise, according to COVID-19 severity, differences were due to maternal risk factors only.

Objective To evaluate the clinical effectiveness of the routine first-trimester screening for preeclampsia (PE) after being implemented in six Catalan maternities. Methods Participants in the reference group were recruited prospectively between October 2015 and September 2017. Participants in the study group were recruited retrospectively between November 2018 and May 2019, after implementing the screening program. PE risk was assessed between 11 + 0 and 13 + 6 weeks of gestation using the Gaussian algorithm combining maternal characteristics, mean arterial blood pressure, uterine artery pulsatility index, and maternal serum pregnancy-associated plasma protein-A. Women with a risk >= 1/137 were prescribed daily salicylic acid (150 mg) until 36 weeks of gestation. Results Preterm PE occurred in 30 of 2641 participants (1.14%) in the reference group, as compared with 18 of 2848 participants (0.63%) in the study group (OR: 0.55; 95% CI, 0.31-0.99; P = 0.045). In the reference group, 37 participants (1.40%) were admitted to ICU, as compared with 23 participants (0.81%) in the study group (OR: 0.57; 95% CI, 0.34-0.96; P = 0.035). Conclusion The routine first-trimester PE screening can be implemented in a public healthcare setting, leading to a significant reduction in the incidence of preterm PE and of maternal ICU admission.

ImportanceAspirin reduces the incidence of preterm preeclampsia by 62% in pregnant individuals at high risk of preeclampsia. However, aspirin might be associated with an increased risk of peripartum bleeding, which could be mitigated by discontinuing aspirin before term (37 weeks of gestation) and by an accurate selection of individuals at higher risk of preeclampsia in the first trimester of pregnancy.ObjectiveTo determine whether aspirin discontinuation in pregnant individuals with normal soluble fms-like tyrosine kinase–1 to placental growth factor (sFlt-1:PlGF) ratio between 24 and 28 weeks of gestation was noninferior to aspirin continuation to prevent preterm preeclampsia.Design, Setting, and ParticipantsMulticenter, open-label, randomized, phase 3, noninferiority trial conducted in 9 maternity hospitals across Spain. Pregnant individuals (n = 968) at high risk of preeclampsia during the first-trimester screening and an sFlt-1:PlGF ratio of 38 or less at 24 to 28 weeks of gestation were recruited between August 20, 2019, and September 15, 2021; of those, 936 were analyzed (intervention: n = 473; control: n = 463). Follow-up was until delivery for all participants.InterventionsEnrolled patients were randomly assigned in a 1:1 ratio to aspirin discontinuation (intervention group) or aspirin continuation until 36 weeks of gestation (control group).Main Outcomes and MeasuresNoninferiority was met if the higher 95% CI for the difference in preterm preeclampsia incidences between groups was less than 1.9%.ResultsAmong the 936 participants, the mean (SD) age was 32.4 (5.8) years; 3.4% were Black and 93% were White. The incidence of preterm preeclampsia was 1.48% (7/473) in the intervention group and 1.73% (8/463) in the control group (absolute difference, −0.25% [95% CI, −1.86% to 1.36%]), indicating noninferiority.Conclusions and RelevanceAspirin discontinuation at 24 to 28 weeks of gestation was noninferior to aspirin continuation for preventing preterm preeclampsia in pregnant individuals at high risk of preeclampsia and a normal sFlt-1:PlGF ratio.Trial RegistrationClinicalTrials.gov Identifier: NCT03741179 and ClinicalTrialsRegister.eu Identifier: 2018-000811-26

The global increase of cyanobacterial blooms occurrence has been associated with the presence of compounds that generate earthy and musty odour in freshwater systems, among which geosmin stands out. The lack of information on the factors associated to geosmin production by benthic organisms has driven the development of this study, whose main goal is to determine the effects of nutrient concentration and DIN:SRP ratio on geosmin formation and release. The experiment was performed in 18 microcosms under controlled conditions for 21 days, using a natural biofilm suspension from Ter river (NE, Spain) to promote biofilm settlement. Six treatments were set crossing three DIN:SRP ratios (A = 4:1, B = 16:1 and C = 64:1) with two nutrient concentrations (Low and High). After 7 days of experiment, geosmin was detected in biofilm, being higher under high nutrient concentration and low DIN:SRP ratio conditions. In this treatment, geosmin in biofilm reached its maximum concentration at day 16 (3.8 ± 0.9 ng/mg), decreasing at the end of the experiment (21d) due to cyanobacteria detachment and geosmin release into the water (136 ± 6 ng/L). Overall, this experimental study showed that high nutrient concentration and low DIN:SRP ratio favoured the Oscillatoria genus development within biofilm communities, generating the optimal conditions for geosmin production. The interaction between these two factors was demonstrated to be a potential driver of benthic geosmin production and release, and should be monitored and controlled in rivers exploited for drinking water purposes. We would like to acknowledge the water utilities Aigües de Vic S.A. and Aigües d'Osona S.A. (Catalonia, Spain), for their funding support in the study presented in this publication. We also want to thank the help provided by Dr. Helena Guasch and Ms. Núria Pou in identifying the algal community present in the biofilm samples, and the help provided by Dr. Victoria Osorio and Dr. Joan Colon in the development of the analytical method for geosmin. The research leading to these results has received funding from the European Research Council (ERC) under the European Union's Horizon 2020 research and innovation program – H2020 INTCATCH (grant agreement n° 689341 ). LP has received funding from the Postdoctoral Fellowships Programme Beatriu de Pinós, funded by the Secretary of Universities and Research (Government of Catalonia) and by the Horizon 2020 Programme of Research and Innovation of the European Union under the Marie Skłodowska-Curie Grant Agreement No. 801370

Abandoned mines cause serious environmental damage to their surroundings with considerable impacts on freshwater ecosystems. These impacts occur mainly due to the uncontrolled discharge of polluted effluents, which may contain high concentrations of heavy metals. Currently, no real solution exists for this important environmental problem, leaving a legacy of global pollution. This study aimed to assess the impact of a metal mining effluent from an abandoned mine on freshwater ecosystems, using aquatic biofilms as an ecological indicator. At the same time, the efficiency of different innovative treatment technologies in reducing the ecological impacts caused by mining effluents was evaluated, consisting of nanofiltration and nanofiltration combined with electrocoagulation. To do that, aquatic biofilms obtained from a pristine stream, were exposed, under microcosms conditions, to a metal mining effluent, untreated or treated by the innovative treatment technologies and responses were compared with unexposed biofilm which served as control. The structural and functional responses of the biofilm were measured with throughout time. Biofilms that were exposed to the untreated mining effluent showed significant differences respect to the rest of treatments and the control, particularly exhibiting inhibitory effects on photosynthetic efficiency just after 24 h of exposure and a progressive shift of the photosynthetic community composition throughout the exposure period. The treatment technologies significantly reduced the ecological impact caused by the metal mining effluent. However, metal bioaccumulation in biofilm revealed a potential long-term impact. These observations evidenced the biofilm as a useful ecological indicator to assess the ecological impact caused by metal mining effluents on freshwaters and the efficiency of different treatment technologies to reduce it. This work was supported by the European Commission LIFE program throughout the LIFE DEMINE project (LIFE16 ENV/ES/000218).

Water reuse is becoming a common practice in several areas in the world, particularly in those impacted by water scarcity driven by climate change and/or by rising human demand. Since conventional wastewater treatment plants (WWTPs) are not able to efficiently remove many organic contaminants and pathogens, more advanced water treatment processes should be applied to WWTP effluents for water reclamation purposes. In this work, a pilot plant based on microfiltration (MF) followed by reverse osmosis (RO) filtration was applied to the effluents of an urban WWTP. Both the WWTP and the pilot plant were investigated with regards to the removal of a group of relevant contaminants widely spread in the environment: 28 pharmaceuticals and 20 pesticides. The combined treatment by the MF–RO system was able to quantitatively remove the target micropollutants present in the WWTP effluents to values either in the low ng/L range or below limits of quantification. Monitoring of water quality of reclaimed water and water reclamation sources is equally necessary to design the most adequate treatment procedures aimed to water reuse for different needs AcknowledgmentsThis research work has been co-financed by the SpanishMinistry of Economy and Competitiveness through the projectSCARCE (Consolider-Ingenio 2010 CSD2009-00065) and the Euro-pean Union through the European Regional Development Fund(ERDF) and partly supported by the Generalitat de Catalunya (Con-solidated Research Group: Catalan Institute for Water Research2014 SGR 291)

Resumen En marzo de 2010 entro en vigor la nueva ley organica de salud sexual y reproductiva y de la interrupcion voluntaria del embarazo en nuestro pais, que entre otros cambios nos permite realizar interrupciones de embarazo a partir de las 22 semanas en determinados supuestos. Este cambio ha provocado que se planteen nuevos protocolos para el manejo de las interrupciones de embarazo tardias. En la mayoria de centros autorizados para la realizacion de interrupciones de embarazo de nuestro pais abogan por un tratamiento medico, especialmente en aquellas gestaciones que superan las 12 semanas. Despues de realizar una revision de la literatura, hemos encontrado diferentes protocolos de actuacion y dosis farmacologicas, especialmente en gestaciones avanzadas de tercer trimestre. Presentamos nuestro protocolo de interrupcion de embarazo, fruto de nuestra experiencia asicomo resultado de la revision de los protocolos y trabajos publicados.

Interactions between emerging contaminants and other drivers of community structure and function are poorly known. We used laboratory microcosms to investigate the single and combined effects of grazing and triclosan toxicity on the structure and function of stream periphyton. Grazing alone strongly reduced algal biomass, but also reduced oxidative stress and increased periphyton productivity and phosphorus (P) uptake capacity. This suggests that grazed algal communities can compensate for reduced biomass by enhanced growth after being released from grazing. Triclosan exposure (11.6 ± 1.1 μg L−1) reduced the detoxification capacity and P-uptake capacity of periphyton and altered diatom taxonomic composition. This indicates that triclosan at environmentally relevant concentrations affects the capacity of periphyton to remove dissolved nutrients and to cope with toxicant mixtures commonly occurring in streams. Triclosan exposure and grazing pressure had negative synergistic effects on algal size-class distribution and diatom mortality, since the effects of triclosan were higher than expected when periphyton was subject to grazing. Periphyton exposed to toxic substances such as triclosan had a lower capacity to cope with grazing than unexposed communities, because toxicity can limit algal regrowth after release from grazing and promote the loss of less abundant species. This synergism may have important implications because grazing pressure will magnify the negative effects of toxicants on community structure and ecosystem functions such as primary production and nutrient cycling This study was supported by the European Commission through the project Modelkey (Project 511237-2 GOCE). Additional funds were provided by the European Keybioeffects Project (MRTN-CT-2006-035695), VIECO (009/RN08/011), SCARCE (Consolider-Ingenio 2010, CSD2009- 00065) and Fluvialmultistress (CTM2009-14111-CO2-01) and MPCUdG2016/120

Resumen El Doppler de las arterias uterinas permite estudiar de forma precoz el fenomeno de la invasion trofoblastica y constituye una herramienta muy util para el cribado de retraso de crecimiento intrauterino y preeclampsia precoz. Existen numerosos estudios que asocian un engrosamiento de la placenta detectado ecograficamente con resultados perinatales desfavorables. Se presenta un caso clinico con Doppler arterias uterinas patologicas asociado a placenta engrosada que requirio de finalizacion urgente por desprendimiento prematuro de placenta normoinserta.

We examined the presence of pesticides in the Llobregat river basin (Barcelona, Spain) and their effects on benthic biological communities (invertebrates and diatoms). The Llobregat river is one of Barcelona’s major drinking water resources. It has been highly polluted by industrial, agricultural, and urban wastewaters, and—as a typical Mediterranean river—is regularly subjected to periodic floods and droughts. Water scarcity periods result in reduced water flow and dilution capacity, increasing the potential environmental risk of pollutants. Seven sites were selected, where we analysed the occurrence of 22 pesticides (belonging to the classes of triazines, organophosphates, phenylureas, anilides, chloroacetanilides, acidic herbicides and thiocarbamates) in the water and sediment, and the benthic community structure. Biofilm samples were taken to measure several metrics related to both the algal and bacterial components of fluvial biofilms. Multivariate analyses revealed a potential relationship between triazine-type herbicides and the distribution of the diatom community, although no evidence of disruption in the invertebrate community distribution was found. Biofilm metrics were used as response variables rather than abundances of individual species to identify possible cause-effect relationships between pesticide pollution and biotic responses. Certain effects of organophosphates and phenylureas in both structural and functional aspects of the biofilm community were suggested, but the sensitivity of each metric to particular stressors must be assessed before we can confidently assign causality. Complemented with laboratory experiments, which are needed to confirm causality, this approach could be successfully incorporated into environmental risk assessments to better summarise biotic integrity and improve the ecological management., This study was supported by the European Commission project MODELKEY (Project 511237-2 GOCE). Additional funds were provided by the European Project Keybioeffects (MRTN-CT-2006-035695), by the Spanish Ministry of Science and Technology (Project GCL2006-12785/HID), and by the programme VIECO (009/RN08/011) of the Ministry of the Environment and Rural and Marine Affairs.

Herbicides affect the structure and functional parameters of fluvial biofilm. Diuron is toxic to primary producers and disrupts endocrine activity. Here, we studied the interaction between this toxicant and several biological compartments in a simple food chain composed of herbivores (the snail Physella [Costatella] acuta) and biofilm. We used indoor experimental channels to which Diuron was added at a realistic concentration (2 mug/L). Bacterial survival and chlorophyll-a and photosynthetic activity were analyzed in the biofilm. We monitored biomass, mortality, reproduction, and motility as end points in the freshwater snail P. acuta. Our results showed that bacterial survival and photosynthetic activity were sensitive to Diuron. Snails were not affected by the herbicide at the concentration tested. No significant interactions between the toxicant and grazers were observed on the biofilm. Reproductive traits, however, were slightly affected, indicating a possible endocrine disruption.

A system of recirculating channels was used in this study to examine the long-term effects (29 d) of environmentally realistic concentrations of the herbicide diuron (from 0.07 to 7 μg L-1) on biofilm communities. The autotrophic activity of biofilms was affected by this herbicide, as reflected by a marked decrease in the photosynthetic efficiency. Diuron exposure also increased chlorophyll-a content and reduced the biovolume of diatom taxa at low concentrations. The effects on bacteria were also remarkable. Bacterial abundance was reduced after a week of exposure to the herbicide at a range of concentrations. Effects were on the number of live bacteria and on the increase in the leucine-aminopeptidase activity. It is suggested that inputs of herbicides to the river ecosystem at low concentrations may cause a chain of effects in the biofilm, which include inhibitory effects on algae but also indirect effects on the relationships between biofilm components. © 2009 Elsevier Ltd. All rights reserved This study was supported by the European Commission project Modelkey (Project 511237-2 GOCE). Additional funds were provided by the European Project Keybioeffects (MRTN-CT-2006-035695) and by the Spanish Ministry of Science and Technology (Project GCL2006-12785/HID) and the VIECO program (009/RN08/011) of the Spanish Ministry of the Environment and Rural and Marine Affairs

We present an overview of possible links between chemical contamination and the diversity of fluvial communities, in order to assess how conventional and more recently developed methodologies used to estimate the diversity of rivers and streams could be used to explore this relationship. We analyze different trophic levels (bacteria, autotrophic biofilm, benthic macroinvertebrates and fish) and discuss their usefulness in diversity-related studies. We present some practical examples of their application. We strongly recommend that future research should involve a multi-index approach and multidisciplinary studies that integrate chemical and biological analyses to assess effectively the relationship between biological diversity and chemical contamination.

The Water Framework Directive of the European Union requires achievement of good chemical and ecological status in river systems. Risk assessment for toxicants is mostly based on individual single-species tests, though extrapolation of such results to ecosystem evaluation is often afflicted with uncertainties. Advances include higher-tier testing, which comprises use of multi-faceted ecotoxicity tests, and community (multi-species) tests. Including several trophic levels in pollutant testing shows that both direct and indirect effects occur in biological communities. Direct effects are expressed as changes in community composition, growth rates, metabolism and death rate. Indirect effects at other trophic levels (primary producers, consumers, predators) are exerted through trophic links. Biofilm-grazers comprise a simple food chain, where potential and negative effects affecting one of them could be magnified through the food web (bottom-up versus top-down effects), thus reinforcing or decreasing the ability of biofilms to be indicators of the effects of toxicants in aquatic ecosystems.

This chapter summarizes field and laboratory investigations dealing with metals and pesticides (90) and emerging compounds’ (10) effects on fluvial communities. The Arkansas River case study is a good example showing how field observations, together with long-term natural experiments and microcosm experiments, provide consistent evidence of metals effects on macroinvertebrate communities. In the case of biofilms, microcosm and mesocosm experiments confirm that metals and pesticides are responsible for the loss of sensitive species in the community, and that this influence is modulated by several biological and environmental factors. Information about the effects of emerging pollutants is very scarce, highlighting the existence of a missing gap requiring future investigations. The examples provided and the recommendations given are proposed as a general guide for studies aiming to link chemical pollution with ecological alterations.

Triclosan is a commonly used bactericide that survives several degradation steps in WWTP (wastewater treatment plants) and potentially reaches fluvial ecosystems. In Mediterranean areas, where water scarcity results in low dilution capacity, the potential environmental risk of triclosan is high. A set of experimental channels was used to examine the short-term effects of triclosan (from 0.05 to 500 μg L−1) on biofilm algae and bacteria. Environmentally relevant concentrations of triclosan caused an increase of bacterial mortality with a no effect concentration (NEC) of 0.21 μg L−1. Dead bacteria accounted for up to 85% of the total bacterial population at the highest concentration tested. The toxicity of triclosan was higher for bacteria than algae. Photosynthetic efficiency was inhibited with increasing triclosan concentrations (NEC = 0.42 μg L−1), and non-photochemical quenching mechanisms decreased. Diatom cell viability was also affected with increasing concentrations of triclosan. Algal toxicity may be a result of indirect effects on the biofilm toxicity, but the clear and progressive reduction observed in all the algal-related endpoints suggest the existence of direct effects of the bactericide. The toxicity detected on the co-occurring non-target components of the biofilm community, the capacity of triclosan to survive through WWTP processes and the low dilution capacity that characterizes Mediterranean systems extend the relevance of triclosan toxicity beyond bacteria in aquatic habitats., This study was supported by the European Commission project Modelkey (Project 511237-2 GOCE). Additional funds were provided by the European Project Keybioeffects (MRTN-CT-2006-035695), the Spanish projects Fluvialfitomarc (GCL 2006-12785/HID), VIECO (009/RN08/011), SCARCE (Consolider-Ingenio 2010, CSD2009-00065) and Fluvialmultiestres (CTM2009-14111-CO2-01), as well as by Consorci de la Costa Brava and Empresa Mixta d’Aigües de la Costa Brava, S.A.

Among increasingly used pharmaceutical products, beta-blockers have been commonly reported at low concentrations in rivers and littoral waters of Europe and North America. Little is known about the toxicity of these chemicals in freshwater ecosystems while their presence may lead to chronic pollution. Hence, in this study the acute toxicity of 3 beta-blockers: metoprolol, propranolol and atenolol on fluvial biofilms was assessed by using several biomarkers. Some were indicative of potential alterations in biofilm algae (photosynthetic efficiency), and others in biofilm bacteria (peptidase activity, bacterial mortality). Propranolol was the most toxic beta-blocker, mostly affecting the algal photosynthetic process. The exposure to 531microg/L of propranolol caused 85% of inhibition of photosynthesis after 24h. Metoprolol was particularly toxic for bacteria. Though estimated No-Effect Concentrations (NEC) were similar to environmental concentrations, higher concentrations of the toxic (503microg/L metoprolol) caused an increase of 50% in bacterial mortality. Atenolol was the least toxic of the three tested beta-blockers. Effects superior to 50% were only observed at very high concentration (707mg/L). Higher toxicity of metoprolol and propranolol might be due to better absorption within biofilms of these two chemicals. Since beta-blockers are mainly found in mixtures in rivers, their differential toxicity could have potential relevant consequences on the interactions between algae and bacteria within river biofilms.

A wide range of human pharmaceuticals are present at low concentrations in freshwater systems, particularly in sections of polluted river. These compounds show high biological activity, often associated with a high stability. These characteristics imply a potential impact of these substances on aquatic biota even when present at low environmental concentrations. Low flow conditions in Mediterranean rivers, most of which flow through densely populated areas and are subjected to intensive water use, increase the environmental risk of these emergent compounds. Here, we studied whether pharmaceuticals in river water affect the local benthic community structure (diatoms and invertebrates). For this purpose, we analyzed the occurrence of pharmaceuticals along the Llobregat River and examined the benthic community structure (diatoms and invertebrates) of this system. Some pharmaceutical products in the Llobregat River registered concentrations greater than those cited in the literature. Multivariate analyses revealed a potential causal association between the concentrations of some anti-inflammatories and beta-blockers and the abundance and biomass of several benthic invertebrates (Chironomus spp. and Tubifex tubifex). Further interpretation in terms of cause-and-effect relationships is discussed; however, it must be always taken with caution because other pollutants also may have significant contributions. Combined with further community experiments in the laboratory, our approach could be a desirable way to proceed in future risk management decisions.

Biofilms can be regarded as early warning systems for detection of the effects of toxicants on aquatic systems, because they have been successfully used for detection of other environmental stressors (e.g. pH, salinity, organic pollution). A variety of methods is used for detection of the effects of toxicants by use of biofilms. The methods range from structurally-based to functionally-based, and from in vitro-based to systemic approaches. Physiological approaches may be appropriate for detection of acute effects. Among these methods, photosynthesis is more related to the effect of toxicants affecting algal communities, directly or indirectly, and extracellular enzyme activity is less specific. Selecting one or the other may depend on the suspected direct effect of the toxicant. Integrated studies have revealed the relevance of toxicants to top-down or bottom-up regulation of the biofilm community. Persistent or chronic effects should affect other biofilm indicators, for example growth or biomass-related factors (e.g. chlorophyll), or community composition. Among these, community composition might better reflect the effects of the toxicant(s), because this may cause a shift from a sensitive to a progressively tolerant community. Community composition-based approaches do not usually adequately reflect cause-effect relationships and require complementary analysis of properties affected in the short-term, for example physiological properties. The current array of methods available must be wisely combined to disentangle the effects of chemicals on biofilms, and whether these effects are transient or persistent, to successfully translate the chemical action of toxicants into the effect they might have on the river ecosystem.

Audiovisual production has an important role to play in Media Literacy, even if it isn’t as developed as critical reading. Any dialogic process of communication includes expression and creation, which is crucial to help youngters to become competent in our societies. To emphasize this, we analysed the contents of 44 audiovisual productions made by teenagers in different educational and social frameworks. These videos have been produced during practical workshops where participants could choose the subjects to deal with. The most popular issues chosen were: teenagers’ self-image and conflicts, with more or less violence. These subjects allow us to learn about the big influence of TV and cinema in the teenagers’ imaginary. La producción audiovisual es un instrumento controvertido en el marco de la «Educación en Comunicación» (EC. Abarca uno de los ejes de la competencia mediática que promueve la EC: el de la «expresión y creación», que suele considerarse de forma bastante independiente al de la «lectura crítica». Pero ambos ejes son fundamentales: cualquier proceso comunicativo-dialógico implica una competencia relacionada con la lectura, comprensión o interpretación a la par que otra ligada a la expresión-creación. Los recelos responden a diferentes motivos. Por un lado, a las preconcepciones existentes sobre las aportaciones cognitivas y formativas que puede suponer la producción de un vídeo. También se cuestiona el sentido del dominio técnico de unos instrumentos que, la mayoría de las veces, los y las adolescentes los usan para idear contenidos similares a los que aporta la industria más comercial. A esto tenemos que añadir los temores que frecuentemente crea el uso de los audiovisuales en situaciones de aula: la aparición de problemas técnicos, el posible descontrol del alumnado, la ruptura de rutinas, etc. Todo este conjunto de aspectos contribuye a que la producción hecha realmente por los y las adolescentes tenga poca relevancia en los centros escolares. Pero esta situación debe replantearse si tenemos en cuenta las características de la sociedad mediática en la que interactúan las chicas y los chicos. Y, en la línea de abordar más a fondo la utilidad y necesidad de la producción audiovisual con adolescentes, se plantea este artículo que recoge el análisis del contenido de 44 relatos audiovisuales breves. Los han realizado chicas y chicos de diferentes contextos socioculturales en talleres de producción audiovisual, coordinados y organizados por Teleduca, educació i comunicació SCP, en el ámbito de la educación formal y no-formal. Los talleres nacen de diferentes objetivos educativos, pero en todos ellos los y las adolescentes trabajan en equipo. El tipo de vídeo que se les sugiere es una ficción sin diálogos sonoros. Un relato sencillo, con pocos acontecimientos, filmado frecuentemente de forma lineal. El hecho de no utilizar palabras sonoras, pero sí música y algunas veces palabras escritas que complementan puntualmente las imágenes, también simplifica el proceso de grabación y edición que realizan los y las jóvenes al tiempo que se mantiene la capacidad expresiva del contenido. Los chicos y chicas construyen estos textos videográficos de forma libre y espontánea. Por tanto, son construcciones representativas de sus intereses y motivaciones, de sus miradas sobre el mundo, así como un espacio para hacer visibles sus voces. Los análisis del contenido temático de los vídeos de ficción ponen en evidencia una gran variedad de aspectos, entre ellos la influencia que tienen el cine y la televisión en su imaginario. Del conjunto de temas que aparecen, el de la autoimagen adolescente y el del conflicto más o menos violento son los que ocupan lugares preeminentes. Temas que, por lo demás, tienen gran presencia en las pantallas del cine y la televisión. Por lo que los chicos y las chicas difícilmente pueden escapar del juego de miradas que comporta su interacción con los medios. Sólo posibilitando la voz y la mirada de las chicas y los chicos, aportándoles recursos para el cuestionamiento crítico de los textos mediáticos a través del análisis y la producción audiovisual, podrán construir nuevos discursos, nuevas formas de representación.

The Llobregat is a Mediterranean river that is severely impacted by anthropogenic pressures. It is characterized by high flow variability which modulates its chemical and biological status. The present work evaluates the effects of flow changes on the concentration of pharmaceutically active compounds (PhACs) and their relationship to cellular parameters of river biofilms. To this end, at two selected sampling sites at the lower course of the Llobregat river, surface water samples were collected twice a week over two hydrologically different periods exhibiting low and high river flows. Higher levels of PhACs were detected at the downstream sampling site. Irrespective of the flow regime, analgesics, anti-inflammatories and lipid regulators were the most abundant substances at both sampling sites with total concentrations of up to1000 ng/L and 550 ng/L at the upstream and downstream sites, respectively. Antibiotics (fluoroquinolones) and psychiatric treatment drugs were also detected at high levels in the second campaign achieving concentrations of up to 500 ng/L. The principal component analysis (PCA) performed with the PhACs concentrations of the two campaigns revealed differences in the various therapeutic groups depending on sampling site and period. After a flash flood event during the second sampling period, dilution of PhACs occurred, but their average concentrations measured before the flood were restored within two weeks. For the majority of compounds, PhAC concentrations displayed an inverse relationship with river discharge The effects of water containing different concentrations of PhACs on biofilm communities were evaluated and related to flow regime variations. Translocation of biofilm communities from a less to a more polluted site of the river demonstrated an increase in bacteria mortality in the translocated biofilms. After the flood, extracellular peptidase activity and chlorophyll-a concentration were significantly reduced, and biofilm growth rate was significantly lower.