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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 relación de agua y ciudad es múltiple y no trata solo del clásico abastecimiento con agua potable, sino que hoy en día hay que considerar, igualmente, el saneamiento y la depuración de las aguas residuales así como, cada vez de forma más creciente, la reutilización de las aguas residuales una vez alcanzado un determinado nivel de calidad. Desde parámetros puramente económicos, la cuantía que representa hoy en día el negocio del agua supera claramente la de otras utilizaciones del agua y, al tiempo, es de una gran complejidad jurídica y organizativa, por el variado número de tasas, impuestos y personas jurídicas (públicas y privadas) que participan en esas actividades. El interés, por tanto, de un riguroso tratamiento de estas cuestiones no necesita justificación. Y ese es el objeto de este libro en el que participan académicos especializados de primera línea así como técnicos y expertos en la relación agua-ciudad. El volumen procede de la realización de las periódicas Jornadas de Derecho de Aguas que la Universidad de Zaragoza y la Confederación Hidrográfica del Ebro, organizan con carácter anual desde 1991.

This study aims to assess the occurrence, fate and temporal and spatial distribution of anthropogenic contaminants in a river subjected to different pressures (industrial, agricultural, wastewater discharges). For this purpose, the Henares River basin (central Spain) can be considered a representative basin within a continental Mediterranean climate. As the studied river runs through several residential, industrial and agricultural areas, it would be expected that the chemical water quality is modified along its course. Thereby the selection of sampling points and timing of sample collection are critical factors in the monitoring of a river basin. In this study, six different monitoring campaigns were performed in 2010 and contaminants were measured at the effluent point of the main wastewater treatment plant (WWTP) in the river basin and at five different points upstream and downstream from the WWTP emission point. The target compounds evaluated were personal care products (PCPs), polycyclic aromatic hydrocarbons (PAHs) and pesticides. Results show that the river is clearly influenced by wastewater discharges and also by its proximity to agricultural areas. The contaminants detected at higher concentrations were the PCPs. The spatial distribution of the contaminants indicates that the studied contaminants persist along the river. In the time period studied no great seasonal variations of PCPs at the river collection points were observed. In contrast, a temporal trend of pesticides and PAHs was observed. Besides the target compounds, other new contaminants were identified and evaluated in the water samples, some of them being investigated for the first time in the aquatic environment. The behaviour of three important transformation products was also evaluated: 9,10-anthracenodione, galaxolide–lactone and 4-amino-musk xylene. These were found at higher concentrations than their parent compounds, indicating the significance of including the study of transformation products in the monitoring programmes.

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.

The degradation of an aqueous solution of fenofibric acid was investigated using ultraviolet (UV) photolysis and UV/H2O2 with a low-pressure mercury lamp. We obtained quantum yields at different temperatures and the rate constant for the reaction of fenofibric acid with hydroxyl radicals. The maximum radical exposure per fluence ratio obtained was 1.4 × 10−10 M L−1 mW−1. Several reaction intermediates were detected by means of exact mass measurements performed by liquid chromatography coupled to quadrupole-time-of-flight mass spectrometry (LC-ESI-QTOF–MS). UV and UV/H2O2 pathways involve the decarboxylation of fenofibric acid to 4-chloro-4′-(1-hydroxy-1-methylethyl)benzophenone and other minor products, predominantly chlorinated aromatics. We detected several intermediates from reactions with hydroxyl radicals and some lower molecular weight products from the scission of the carbonyl carbon-to-aromatic-carbon bond. We recorded high toxicity in UV irradiated samples for the growth of Pseudokirchneriella subcapitata even after the total depletion of fenofibric acid; this was probably due to the presence of chlorinated aromatics. A degree of toxicity reappeared in highly irradiated UV/H2O2 samples, probably because of the formation of ring-opening products. The degree of mineralization was closely related to that of dechlorination and reached values of over 50% after 3–4 min before stabilizing thereafter.