Climate change impact on karstic aquifer hydrodynamics in southern Europe semi-arid region using the KAGIS model.

Nowadays, there are many urban settlements in arid and semiarid areas supplied by groundwater from adjacent small aquifers. Climate projections with expected decreases in averages precipitation values jointly with increases in the frequency of heavy rainfall events does not show a clear pattern to how water resources in karstic aquifers are going to evolve. This paper, focused in the province of Alicante (Southeast of Spain), assesses the behaviour of a small karstic aquifer, the Mela aquifer, whose resources supply urban water consumption for close municipalities. We assess the hydrogeological response of the aquifer, through the KAGIS black-box GIS-based model, for the present climate conditions and for the long period analysing the four scenarios provided by the International Panel of Climate Change. Main results prove that, if we do not diminish the greenhouse gas emissions, the climate change impact on the hydrological response of the study aquifer shows a decrease in the flow rate from its unique spring and will be non-existent during the summer months. So, it will be necessary to design supply strategies for these municipalities and to carry out them, meeting budget restrictions and avoiding potential water shortages.

Standardisation and half-life of 89Zr.

The nuclide 89Zr is being tested for the labelling of compounds with long blood circulation times. It decays by beta plus emission (22.8%) and by electron capture (77.2%) to 89Y. Its half-life has been determined by following the decay rate with two measurement systems; an Ionisation Chamber and an HPGe detector. The combination of six results gives a value of T1/2 = 78.333 (38) h, slightly lower than the DDEP recommended value of 78.42 (13) h. This radionuclide has also been standardised by liquid scintillation counting, 4πγ counting and coincidence techniques.

Results of an international comparison of activity measurements of 68Ge.

An international key comparison, identifier CCRI(II)-K2.Ge-68, has been performed. The National Institute of Standards and Technology (NIST) served as the pilot laboratory, distributing aliquots of a 68Ge/68Ga solution. Results for the activity concentration, CA, of 68Ge at a reference date of 12h00 UTC 14 November 2014 were submitted by 17 laboratories, encompassing many variants of coincidence methods and liquid-scintillation counting methods. The first use of 4π(Cherenkov)ß-γ coincidence and anticoincidence methods in an international comparison is reported. One participant reported results by secondary methods only. Two results, both utilizing pure liquid-scintillation methods, were identified as outliers. Evaluation using the Power-Moderated Mean method results in a proposed Comparison Reference Value (CRV) of 621.7(11)kBqg-1, based on 14 results. The degrees of equivalence and their associated uncertainties are evaluated for each participant. Several participants submitted 3.6mL ampoules to the BIPM to link the comparison to the International Reference System (SIR) which may lead to the evaluation of a Key Comparison Reference Value and associated degrees of equivalence.

Matrix solid-phase dispersion followed by liquid chromatography tandem mass spectrometry for the determination of selective ciclooxygenase-2 inhibitors in sewage sludge samples.

A straightforward single-step extraction method based on matrix solid-phase dispersion (MSPD), followed by high-performance liquid chromatography with hybrid quadrupole time of flight mass spectrometry (LC-QTOF-MS), was developed and optimized to determine five non-steroidal anti-inflammatory drugs (Valdecoxib, Etoricoxib, Parecoxib, Celecoxib and 2,5-Dimethylcelecoxib) in sewage sludge samples. The influence of different operational parameters on the extraction efficiency a well as in the matrix effects of the produced extracts was evaluated in detail. Under final working conditions, freeze dried samples (0.2g) were first soaked with 100µL of aqueous potassium hydroxide solution (60%, w/v), mixed with 1g of anhydrous sodium sulfate and dispersed with 1g of Florisil. This blend was transferred to the top of a polypropylene column cartridge containing 3g of silica. Analytes were recovered using 15mL of hexane/acetone (1:2, v/v) mixture. The extracts were concentrated by evaporation and reconstituted with 1mL of methanol/water (1:1, v/v), filtered and injected in the LC system. Quantification limits from 0.005 and 0.05ngg(-1) and absolute recoveries between 86 and 105% were achieved. Results indicated the presence of two of the targeted COXIBs in real samples of sewage sludge, the highest average concentration (22ngg(-1)) corresponding to celecoxib. Moreover, the screening capabilities of the LC-QTOF-MS system demonstrated that the developed MSPD extraction procedure might be useful for the selective extraction of some other pharmaceuticals (e.g. amiodarone and their metabolite N-desethylamiodarone, miconazole, clotrimazole and ketoprofen) from sludge samples.

Preparation and characterisation of a (226)Ra spiked slag as reference material for radioactive control of steelworks.

One of the issues of the European Research Project MetroMetal is to develop reference materials in order to provide SI-traceable radioactivity monitoring in foundries. For this purpose, a protocol for preparing a set of identical standard slag samples, containing known activity concentrations of (226)Ra, has been developed. This paper describes the preparation of the raw material, the characterisation in terms of its mineralogical, chemical and radiological features, the spiking procedure and the homogeneity testing of the spiked samples.

Development of an ionic liquid based dispersive liquid-liquid microextraction method for the analysis of polycyclic aromatic hydrocarbons in water samples.

A simple, rapid and efficient method, ionic liquid based dispersive liquid-liquid microextraction (IL-DLLME), has been developed for the first time for the determination of 18 polycyclic aromatic hydrocarbons (PAHs) in water samples. The chemical affinity between the ionic liquid (1-octyl-3-methylimidazolium hexafluorophosphate) and the analytes permits the extraction of the PAHs from the sample matrix also allowing their preconcentration. Thus, this technique combines extraction and concentration of the analytes into one step and avoids using toxic chlorinated solvents. The factors affecting the extraction efficiency, such as the type and volume of ionic liquid, type and volume of disperser solvent, extraction time, dispersion stage, centrifuging time and ionic strength, were optimised. Analysis of extracts was performed by high performance liquid chromatography (HPLC) coupled with fluorescence detection (Flu). The optimised method exhibited a good precision level with relative standard deviation values between 1.2% and 5.7%. Quantification limits obtained for all of these considered compounds (between 0.1 and 7 ng L(-1)) were well below the limits recommended in the EU. The extraction yields for the different compounds obtained by IL-DLLME, ranged from 90.3% to 103.8%. Furthermore, high enrichment factors (301-346) were also achieved. The extraction efficiency of the optimised method is compared with that achieved by liquid-liquid extraction. Finally, the proposed method was successfully applied to the analysis of PAHs in real water samples (tap, bottled, fountain, well, river, rainwater, treated and raw wastewater).

Optimization of the matrix solid-phase dispersion sample preparation procedure for analysis of polycyclic aromatic hydrocarbons in soils: comparison with microwave-assisted extraction.

A fast and simple preparation procedure based on the matrix solid-phase dispersion (MSPD) technique is proposed for the first time for the isolation of 16 polycyclic aromatic hydrocarbons (PAHs) from soil samples. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-c,d]pyrene were considered in the study. Extraction and clean-up of samples were carried out in a single step. The main parameters that affect extraction yield, such as dispersant, type and amount of additives, clean-up co-sorbent and extractive solvent were evaluated and optimized. The addition of an alkali solution in MSPD was required to provide quantitative recoveries. Analytical determinations were carried out by high performance liquid chromatography (HPLC) with fluorescence detection. Quantification limits (between 0.01 and 0.6 ng g(-1) dry mass) were well below the regulatory limits for all the compounds considered. The extraction yields for the different compounds obtained by MSPD were compared with the yields obtained by microwave-assisted extraction (MAE). To test the accuracy of the MSPD technique, the optimized methodology was applied to the analysis of standard reference material BCR-524 (contaminated industrial soil), with excellent results.

Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction.

A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 microg kg(-1) dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials.

Approaches for the simultaneous extraction of tetrabromobisphenol A, tetrachlorobisphenol A, and related phenolic compounds from sewage sludge and sediment samples based on matrix solid-phase dispersion.

A procedure based on matrix solid-phase dispersion (MSPD) for sample preparation in the analysis of some bromophenols and halogenated bisphenols in sediments and sludges has been developed. For the first time ever, MSPD was applied for the extraction of organic contaminants from sediment and sewage sludge samples. The influence of experimental conditions on the yield of the extraction process and on the efficiency of the built-in cleanup step was thoroughly evaluated. Analysis of the extracts was performed by nonaqueous capillary electrophoresis coupled with photodiode array ultraviolet detection, using large-volume sample stacking injection based on the electroosmotic flow pump as an on-column preconcentration technique. The method was applied to the analysis of real sludges from urban sewage treatment plants, as well as river and marine sediment samples.

Application of matrix solid-phase dispersion in the analysis of priority polycyclic aromatic hydrocarbons in fish samples.

The performance of matrix solid-phase dispersion (MSPD) for the extraction of polycyclic aromatic hydrocarbons (PAHs) in fish tissue is described. The suitability of different solid supports was tested as well as the influence on the extraction efficiency of the natural fat content in samples. Under optimal conditions 0.6-0.8 g of tissue sample, are dispersed with 2 g of octadecylsiloxane (C18) and 0.5 g of anhydrous sodium sulphate and transferred to the top of a polyethylene solid-phase extraction cartridge which already contains 2 g of florisil and 1 g of C18. Cartridges were eluted with acetonitrile. The analysis of the extracts was carried out by high-performance liquid chromatography (HPLC) coupled with fluorescence detection. The proposed method provides detection limits between 0.04 and 0.32 ng/g for the different considered PAHs, below the maximum levels established by the some regulatory bodies for the six PAHs after recent oil spill episodes and European Union regulations. Recoveries over 80% were obtained for all compounds. Accuracy validation was carried out using the US National Institute of Standards and Technology (NIST) SRM 2977 reference material.

Analysis of tetrabromobisphenol A and other phenolic compounds in water samples by non-aqueous capillary electrophoresis coupled to photodiode array ultraviolet detection.

Non-aqueous capillary electrophoresis (NACE) with large-volume sample stacking injection using the electroosmotic flow pump (LVSEP) has been developed for the determination of tetrabromobisphenol A (TBBPA) and other phenolic compounds in environmental matrices. Methanol has been used as run buffer solvent to reduce the electroosmotic flow (EOF). Identification and quantification of the analytes was performed by photodiode array ultraviolet detection. LVSEP-NACE improved sensitivity of the peak height by 90-300-fold. The method developed was applied to the analysis of TBBPA in river water and wastewater samples, using solid-phase extraction (SPE) as sample pretreatment process. The average recoveries of the analytes were in the range of 96-106% and 73-103% for 1 L of river water and 0.5 L of wastewater samples, respectively. When the method was based on off line SPE-LVSEP-NACE, sensitivity was improved by 3300-4500-fold and 1600-2200-fold for river water and wastewater samples, respectively.

Comparative study of aqueous and non-aqueous capillary electrophoresis in the separation of halogenated phenolic and bisphenolic compounds in water samples.

Capillary zone electrophoresis methods, based on either aqueous and non-aqueous solutions as running buffers and UV spectrophotometric detection, have been developed and optimized for the separation of several halogenated phenolic and bisphenolic compounds, suspected or proved to exhibit hormonal disrupting effects. Both aqueous capillary electrophoresis (CE) and non-aqueous capillary electrophoresis (NACE) methods were suitable for the analysis of compounds under study. The separation of the analytes from other 25 potentially interfering phenolic derivatives was achieved with NACE method. Large-volume sample stacking using the electroosmotic flow pump (LVSEP) was assayed as on-column preconcentration technique for sensitivity enhancement. LVSEP-CE and LVSEP-NACE improved peak heights by 5-26 and 16-330 folds, respectively. To evaluate their applicability, the capillary electrophoresis methods developed were applied to the analysis of water samples, using solid-phase extraction as sample pre-treatment process.

Strategic sample composition in the screening of polycyclic aromatic hydrocarbons in drinking water samples using liquid chromatography with fluorimetric detection.

The screening of polycyclic aromatic hydrocarbons in water samples by means of the strategic sample composition (SSC) technique is presented. SSC uses special supersaturated composition matrices to perform sample composition and analysed the results obtained in the analytical determination of these composite samples by means of evolutionary assisted regression procedures providing estimations of the concentration levels of analytes in each individual sample specimen. Here, 12 composite samples were prepared by departing from 26 water sample specimens, five of which were spiked with known amounts of several polycyclic aromatic hydrocarbons (PAHs). These composite samples were analysed by HPLC using fluorescence detection. Concentration levels spiked were, in some cases clearly higher than allowed limits for drinking waters, whereas in other cases are just in the limit or even down these limits. The study shows the ability of SSC to detect the really contaminated samples and guiding the analyst in taking the adequate decisions.

Application of chromatographic and electrophoretic methodology to the speciation of organomercury compounds in food analysis.

Trace metals such as mercury, especially its organic compounds, are an important risk to the environment and to man due to their accumulation in the food chain. For this reason, the routine determination of the very toxic methylmercury, and of other organic and inorganic mercury compounds in marine and land animals, vegetables, fruits and fresh water is of increasing importance in health and environmental control programmes throughout the world. The majority of speciation methods for organomercurials involve a series of fundamental steps for the identification and quantification of samples of biological origin: extraction or isolation from the matrix; derivatisation and concentration; detection; separation of different species of interest and of interference. Each of these steps, as part of the chromatographic analysis of MeHg and of other organomercurials is revised in this study using food samples.

Evaluation of two solid-phase extraction procedures for the preconcentration of chlorophenols in drinking water.

Two off-line concentration procedures for the determination of sixteen chlorophenols in drinking water were developed. One involves acetylation of the samples and their subsequent preconcentration over graphitized carbon black cartridges. In the other, chlorophenols are derivatized following preconcentration over cross-linked styrene-divinylbenzene. The two proposed procedures are compared in terms of chlorophenol recoveries, throughput and breakthrough volume of the cartridges. The acetylated derivatives of chlorophenols are determined highly selectively at the concentration levels established by international legislation using gas chromatography in combination with microwave induced plasma atomic emission spectroscopy.

Determination of phenolic pollutants in drinking water by capillary electrophoresis in the sample stacking mode.

A method for the determination of phenol, chlorophenols and nitrophenols at levels below those allowed by international legislation in water from the public supply is proposed. Ten of the compounds studied are included on the USA Environmental Protection Agency priority list of aquatic pollutants. Samples are concentrated off-line on cross-linked polystyrene and subsequently subjected to capillary electrophoresis using the sample stacking procedure to remove the matrix. The recoveries afforded by the off-line concentration process and the behaviour of the phenols in relation to sample stacking injection were examined.

Speciation of organotin compounds in marine biomaterials after basic leaching in a non-focused microwave extractor equipped with pressurized vessels.

A rapid method for the speciation of butyl- and triphenyltin compounds in marine biotissues is described. A non-focused microwave extractor, operating at a power of 950 W and equipped with 12 pressurized vessels, was used to achieve fast sample leaching with tetramethylammonium hydroxide. The pH of the liquid extract was adjusted to 5. Organotins were ethylated with sodium tetraethylborate, extracted in isooctane and determined by means of a microwave-induced plasma atomic emission detector coupled to a gas chromatograph. The stability of butyl and phenyl compounds, exposed to the microwave energy, was studied as a function of the vessel temperature. The possibility of simultaneous carried-out extractions and the use of microwave to perform the ethylation and extraction of organotin compounds was also studied. The full procedure was validated with certified material NIES-11 and with real samples, by comparison with a classic leaching method using tetramethylammonium hydroxide without microwave.

[Massive hemoptysis associated with tracheopathia osteochondroplastica]. / Hemoptisis masiva asociada a traqueopatía osteocondroplásica.

A patient with a history of recurrent respiratory infections and hemoptysis due to tracheopathia osteochondroplastica is presented. Two aspects are highlighted. On the one hand, the fact that this entity is still, frequently, an unexpected finding at fiberoptic bronchoscopy. On the other hand, the possibility of massive hemoptysis complicating the carrying out of fiberoptic bronchoscopic examination in this process.

Determination of chlorophenols in drinking water samples at the subnanogram per millilitre level by gas chromatography with atomic emission detection.

The use of an atomic emission detector following a process of preconcentration of drinking water samples by a factor of 1500:1 allows the highly selective determination of chlorophenols present in samples below the maximum limit of 0.5 ng/ml set by international regulations. The preconcentration of the samples is carried out using 0.25-g commercial graphitized carbon cartridges without the need for sample derivatization prior to solid-phase extraction.

Speciation of organomercurials in marine samples using capillary electrophoresis.

A rapid method for speciation and determination of organomercury compounds in biological samples of marine origin using Capillary Electrophoresis (CE) is reported. Organomercurials were extracted from the samples by means of the classical Westöö procedure thus giving organomercury-cysteine complexes which can be separated from each other by means of CE resulting in effective speciation. Electrophoretic separation was achieved in an open silica capillary tube at 15-18 kV using a 100mM sodium borate buffer (pH 8.35). All mercury species were distinctively separated within 12 min. Results are presented for the analysis of real marine samples and reference materials, and compared with those obtained by the GC commonly accepted procedure.