BUSCADOR RECOLECTA

As normal municipal wastewater treatment plants (MWTP) are not able to entirely degrade xenobiotic substances, this study focuses on modified solar photo-Fenton treatment (5 mg L−1 Fe, initial pH ≈ 7) of a municipal wastewater treatment plant (MWTP) effluent. However, effluents do not contain compounds which could form photoactive Fe3+ complexes. The use of ferrioxalate, humic substances (HA) and mixing the MWTP effluent with small amounts of influent could be justified to form photoactive Fe3+ complexes. All experiments were done in MWTP effluent spiked (5 or 100 μg/L) with 15 emerging contaminants (ECs) using a pilot compound parabolic collector (CPC) solar plant designed for solar photocatalytic applications. Dissolved organic carbon and UPLC–UV (with prior solid phase extraction) were applied for evaluating the results. The oxalate-enhanced process provided satisfactory EC degradation results but low residual pH of the treated water. HA (10 mg L−1) enhanced the process, balancing degradation time and residual pH. Mixing of MWTP influent and effluent delivered rather disappointing results, as EC degradation was unsuccessful in all cases tested.

Modern water policy requires new kinds of economic information in order to improve the ability of stakeholders and water authorities to analyze the whole set of alternatives available, to provide transparency and to assess and adapt water decisions to the emerging water management challenges. Considering this, we present an overview of the main drivers of economic information in the European water policy agenda as defined by the Water Framework Directive. After a brief introduction, the paper explains how basic economic statistics have been used to carry out the economic analysis of water use for the preparation of river basin management plans. We present the strategies used to enhance the usefulness of the economic information already available. The paper ends with a reflection on what parts of the economic information gaps have been satisfactorily dealt with and what the remaining gaps are.

A simple method using direct sample injection combined with liquid chromatography tandem mass spectrometry has been developed for the simultaneous analysis of six alkaloid compounds in environmental samples. The target list includes two psychostimulants (nicotine and caffeine), three metabolites (cotinine, nicotinic acid and paraxanthine) and a coffee chemical (trigonelline). The analytical method was evaluated in three different matrices (surface water, influent and effluent wastewater). The method developed showed an adequate sensitivity, below 0.6 μg L(-1) for wastewater and 0.1 μg L(-1) for river matrices, without any prior treatment of the samples. Finally, the methodology was applied to real samples for evaluation of their removal from a sewage treatment plant and their persistence/fate in the aquatic environment. All compounds studied in this work were detected at all sampling points collected along the Henares River. However, nicotinic acid was only detected three times in treated sewage samples at levels above its detection limit.

This work details a rapid analytical method using direct sample injection for the simultaneous identification/quantification of 22 drugs of abuse, including some of their major metabolites, in environmental samples. This has been developed using a hybrid triple quadrupole-linear ion trap-mass spectrometer (QqLIT). With the increasing sensitivity of today's tandem mass spectrometers, direct injection analysis of water samples has become an attractive alternative to traditional analytical protocols, which often include a preliminary pre-concentration step. What's more, this kind of analysis is in accordance with many of the main objectives of so-called green analytical chemistry, or environmentally friendly practice. The analytical performance of the LC–MS/MS method was evaluated in three different water matrices (surface water, influent and effluent wastewater). Data acquisition was carried out in selected reaction monitoring (SRM) mode under time-scheduled conditions, monitoring two SRM transitions for simultaneous identification/quantification of all target compounds in the samples. Additionally, an experiment was performed using the information-dependent acquisition (IDA) scan to carry out the identification of those analytes for which the second transition was present at a low intensity. Finally, the two methodologies developed were applied to real samples for evaluation.

Barbronia weberi, an Asian leech, was found in September-October 2010 in a river from Central Spain. This is the first record of the species for the Iberian Peninsula and the Jarama River in particular, where in September-October 2010 the leech was collected during sampling for a bioassessment program. On the program's completion we expect to observe the seasonal dynamic of B. weberi population in the Jarama River.

Los paisajes culturales y el patrimonio del agua, como dos recursos interrelacionados que encierran importantes valores (naturales, económicos, estéticos, productivos, simbólicos, etc.), han sido un tema de alerta colectiva en estos últimos años, debido a la pérdida de bienes patrimoniales y a los actuales cambios socioeconómicos, ambientales y cultuales. Este trabajo presenta un análisis conceptual del binomio paisaje y patrimonio, con la finalidad de potenciar su conocimiento científico más allá de una simple conservación. La revisión bibliográfica muestra que existe una necesidad de valorar estos recursos con nuevos enfoques multidiciplinarios. El análisis realizado constituye una herramienta potencial de conocimientos, que nos permite tener un marco teórico a la hora de emplear guías de diagnóstico y evaluación a los recursos hídricos, permitiéndonos de esta manera tomar mejores decisiones sobre estrategias, categorización de valores del patrimonio, tecnologías, técnicas y políticas eficaces de ordenación.

La agricultura es un sector clave en la economía rural y constituye un motor de crecimiento en regiones del sur de España capaces de desarrollar un regadío competitivo de alto rendimiento. Este es el caso de determinadas comarcas de la Cuenca del Guadalquivir y del Segura, que no obstante afrontan los problemas derivados de la escasez creciente de agua y de un riesgo de sequía cada vez más acusado. Para responder más efectivamente a estos problemas, se han aprobado recientemente una serie de Planes de Sequía que pretenden ofrecer una respuesta planeada y anticipada que sustituya a la gestión de emergencias del pasado. En este trabajo se estudia el impacto previsible de las reglas de decisión de dichos Planes de Sequía (aprobados sin ningún estudio previo sobre las repercusiones económicas de su aplicación), con el objetivo de evaluar si estos contribuyen o no a la sostenibilidad del regadío y por lo tanto de la economía rural y regional que se sustenta sobre esta actividad económica. Se desarrolla un modelo estocástico para evaluar las pérdidas económicas derivadas de la aplicación de los Planes de Sequía en el sector agrario, concluyendo que tales planes no suponen un avance en la sostenibilidad del regadío ni en la garantía de suministro para usos prioritarios.

The identification of transformation products (TPs) of pharmaceuticals in the environment is essentially a challenging task due to the lack of standards and the instrumental capabilities required to detect compounds (sometimes unknowns) that are produced under environmental conditions. In this work, we report the use of liquid chromatography/electrospray quadrupole time-of-flight mass spectrometry (LC/QTOF-MS/MS) as a tool for the identification of amoxicillin (AMX) and its main TPs in wastewater and river water samples. Laboratory degradation experiments of AMX were performed in both alkaline and acidic media in order to confirm that the expected transformation pathway in the aquatic media is through the β-lactam ring cleavage. A thorough study was carried out with both standards and real samples (wastewater and river water samples). Four compounds were identified as main TPs: both amoxicillin diketopiperacine-2',5' and amoxilloic acid diastereomers. Amoxilloic acid stereoisomers are reported for the first time in environmental matrices. The transformation product (5R)-amoxicillin diketopiperacine-2',5' was frequently detected in river waters. Besides, another AMX transformation product formed during analysis was also structurally elucidated for the first time (amoxicilloic acid methyl ester) via accurate mass measurements. Collected data show that although AMX is not present as such in environmental samples, different TPs occur. This study represent a valuable indicator of the potential of LC/QTOF-MS/MS for the identification and structural elucidation of TPs in the environment using accurate MS/MS experiments, enabling thus the recognition of the environmental transformation pathway.

The physicochemical properties of nanoparticles determine their interaction with living organisms. Four different cerium oxide nanoparticles, including commercial materials, were characterized and compared with a micron-sized ceria. The formation of aggregates as well as ζ-potential, surface area, and chemical composition were determined. The formation of primary particle aggregates was a slow process that led to different particle sizes depending on the composition of the medium. In this paper, we describe the toxicity of cerium oxide for the self-luminescent cyanobacterial recombinant strain Anabaena CPB4337 and the green alga Pseudokirchneriella subcapitata. The toxicity for Anabaena exposed to nanoparticles in pure water for 24 h ranged from 0.27 to 6.3 mg/l; P. subcapitata EC(50) (yielded effective concentration of nanoparticles that inhibits the cellular function of interest by 50%) values in the 2.4-29.6 mg/l range. Images of both organisms showed membrane disruption and highly damaged cells. Free cerium was highly toxic for both organisms, but the negligible amount found dissolved in the nanoparticle suspensions could not explain the observed toxic effect of nanoceria on the aquatic organisms; the dissolution of zinc could contribute to the toxicity of bulk material but could not explain the toxic effect of nanoceria either. We found no evidence of nanoparticle uptake by cells, but our observations suggested that their toxic mode of action required direct contact between nanoparticles and cells; in the case of the cyanobacterium, cells completely coated by layers of ceria nanoparticles were observed. Cell damage most probably took place by cell wall and membrane disruption; further research is needed to find out whether the oxidative activity of ceria could be responsible.

The system ozone and hydrogen peroxide was used to reclaim wastewater from the secondary clarifier from a Sewage Treatment Plant (STP) of Alcalá de Henares (Madrid-Spain). The assays were performed by bubbling a gas mixture of oxygen and ozone, with approximately 24 g Nm(-3) of ozone concentration, through a volume of wastewater samples for 20 minutes at 25 degrees C. The removal of dissolved micropollutants such as Pharmaceutical and Personal Care Products (PPCPs) and Organic Carbon (TOC) was enhanced by adding periodic pulses of hydrogen peroxide while keeping pH above 8.0 throughout the runs. Removal efficiency ratios in the range of 7-26 mg O3/mg TOC and 0.24 mg O3/ng micropollutants at 5 minutes of ozonation were assessed as reference data to reclaim wastewater from STP. The relation between the extent of TOC removed and ozone doses used was related by a second-order kinetic model in which the time-integrated ozone-hydrogen peroxide concentration was included.