Estudi de la qualitat físico-química de les aigües dels curs baix del riu congost al llarg de l'any 1982

The Besòs basin is one of the most polluted aras in Catalonia, basically due to the high discharge of industrial and domestic effluents and the insuficient waste water treatment plants. The Congost river is a 41 Km long tributary of Besòos river so the study of his water quality is necessary to carry out an overall study of the basin. In the present work the study of the physicochemical quality of the lower watercourse of the Congost river is carried out in five sampling points and in three wells at 50 m near the river. The parameters measured are: temperature, pH, conductivity, alkalinity, total hardness, chloride, non filtrable residue, chemical oxygen demand, ammoniacal nitrogen, organic + ammoniacal nitrogen, detergents, phosphates, hexavalent chromium, total cyanide, biochemical oxygen demand, and nitrite. All parameters were measured once a month during 1982

Estudi de la contaminació química de les aigües subterrànies de Parets del Vallès

La zona objecte d'estudi, riu Tenes-riera Seca, terme municipal de Parets del Vallès, correspon a un aqüífer lliure de litologia de sorres i graves, amb nivells llimosos intcrcalats. D'acord amb la vulnerabilitat de l' aqüífer i amb el seu comportament hidrodinàmic, aquest aqüífer es veu força afectat per les aigüs superficials que són notablement contaminades. Hom estima els abocaments en la conca del Tenes en 8.825 m3 dia-1, amb 3.724 kg s.s. dia-1; els abocaments domèstics corresponen a 1.164 kg DBO5 dia-1 i els industrials a 2.473 kg DBO6 dia-1; aquests darrers s'inicien a partir de Lliçà de Munt i han estat ben estudiats pel Departament de Química Analítica durant els anys 1980 i 1981. El present treball, efectuat dins el terme municipal de Parets del Vallès, ha consistit en mostreigs i anàlisis sistemàtics de l'aigua de diferents pous de la zona, a ambdós vessants i a distàncies diferents del riu Tenes. La comparació de les diferents característiques dels pous mostrejats posa de manifest la representativitat del mostreig. Els resultats mostren canvis en la qualitat de l'aigua que no sempre s'avenen amb les caracteístiques del model hidroquímic preestablert. Hom aprofundeix també l'estudi de les característiques físico-químiques i de contaminació per metalls pesants. Els resultats palesen que es tracta d'aigües hidrogenocarbonatades càlciques del tipus rHCO3-+ rSO4 2- < rCa2+ + rMg2+, rCl- > rNa+ (segons Alekine) amb un i.c.b. > O. Es mostra una relació clara de les aigües subterrànies amb les aigües superficials, de característiques similars excepte en el fet que la relació rNa+/rCa2+ és més elevada per a aquestes últimes, fet que és justificat pel bescanvi de bases (i.c.b.) Hom avalua també el sistema de mostreig, la representativitat dels punts escollits, les dades obtingudes en relació amb la vulnerabilitat de l'aqüifer i els mètodes analítics utilitzats. L'estudi d'elements abasta el Pb, Cd, Cu, Hg, Cr(VI) i B, considerant la incidència sanitària i ambiental. A part, hom estableix les diferents cartes hidroquímiques (diagrames de Stiff i de Scholler Berkaloff) per tal de comparar les dades obtingudes i la representativitat del sistema.In the present work a study of chemical characterization of groundwaters, based on their ionic ratios, as well as metal trace determination is carried out in Parets del Valles, an industrialized village near Barcelona (Catalonia). Thirteen parameters have been analyzed in seventeen wells and from the data obtained, Schoeller-Berkaloff, modified Stiff and Piper-Hill-Langelier diagrams have been constructed, in order to settle the different groups characterizing proundwatcrs in the studied zone. Nitrate content has been specially studied because his occurrence is highly related with the use of fertilizers in agricultural areas. Sampling and analytical procedures are described. All samples studied are calcium hydrogencarbonate type with rHCO3-+ rSO4 2- < rCa2+ + rMg2+, rCl- > rNa+ according Alekine, and with c.b.i. > O. The results show a clear relationship between groundwaters and surface waters quality. On the other hand a study of Pb, Cu, Cd, Hg, Cr and B is carried out in twenty four wells. The analytical methods used are AAS for Pb, Cu, Cd ang Hg, and ICP-AES method for B and Cr. The contents are compared with those measured in surface waters corresponding to four sampling points in Tenes river that crosses the zone

Inorganic arsenic determination in food: a review of analytical proposals and quality assessment over the last six years

Here we review recent developments in analytical proposals for the assessment of inorganic arsenic (iAs) content in food products. Interest in the determination of iAs in products for human consumption such as food commodities, wine, and seaweed among others is fueled by the wide recognition of its toxic effects on humans, even at low concentrations. Currently, the need for robust and reliable analytical methods is recognized by various international safety and health agencies, and by organizations in charge of establishing acceptable tolerance levels of iAs in food. This review summarizes the state of the art of analytical methods while highlighting tools for the assessment of quality assessment of the results, such as the production and evaluation of certified reference materials (CRMs) and the availability of specific proficiency testing (PT) programmes. Because the number of studies dedicated to the subject of this review has increased considerably over recent years, the sources consulted and cited here are limited to those from 2010 to the end of 2015

Occurrence of inorganic arsenic in edible Shiitake (Lentinula edodes) products

The present study reports arsenic speciation analysis in edible Shiitake (Lentinula edodes) products. The study focused on the extraction, and accurate quantification of inorganic arsenic (iAs), the most toxic form of arsenic, which was selectively separated and determined using anion exchange LC-ICPMS. A wide variety of edible Shiitake products (fresh mushrooms, food supplements, canned and dehydrated) were purchased and analysed. A cultivated Shiitake grown under controlled conditions was also analysed. The extraction method showed satisfactory extraction efficiencies (>90%) and column recoveries (>85%) for all samples. Arsenic speciation revealed that iAs was the major As compound up to 1.38 mg As per kg dm (with a mean percentage of 84% of the total arsenic) and other organoarsenicals were found as minor species. Shiitake products had high proportions of iAs and therefore should not be ignored as potential contributors to dietary iAs exposure in populations with a high intake of Shiitake products

Occurrence of arsenic species in algae and freshwater plants of an extreme arid region in northern Chile, the Loa River Basin

This study reports data on arsenic speciation in two green algae species (Cladophora sp. and Chara sp.) and in five aquatic plants (Azolla sp., Myriophyllum aquaticum, Phylloscirpus cf. desserticola, Potamogeton pectinatus, Ruppia filifolia and Zannichellia palustris) from the Loa River Basin in the Atacama Desert (northern Chile). Arsenic content was measured by Mass Spectrometry coupled with Inductively Coupled Plasma (ICP-MS), after acidic digestion. Liquid Chromatography coupled to ICP-MS was used for arsenic speciation, using both anionic and cationic chromatographic exchange systems. Inorganic arsenic compounds were the main arsenic species measured in all samples. The main arsenic species in the extracts of freshwater algae and plants were arsenite and arsenate, whereas glycerol-arsenosugar (gly-sug), dimethylarsinic acid (DMA) and methylarsonic acid (MA) were present only as minor constituents. Of the samples studied, algae species accumulated more arsenic than aquatic plants. Total arsenic content ranged from 182 to 11,100 and from 20 to 248 mg As kg-1 (d.w.) in algae and freshwater plants, respectively. In comparison with As concentration in water samples, there was hyper-accumulation (>0.1% d.w.) in Cladophora sp

Accuracy of a method based on atomic absorption spectrometry to determine inorganic arsenic in food: outcome of the collaborative trial IMEP-41

A collaborative trial was conducted to determine the performance characteristics of an analytical method for the quantification of inorganic arsenic (iAs) in food. The method is based on (i) solubilisation of the protein matrix with concentrated hydrochloric acid to denature proteins and allow the release of all arsenic species into solution, and (ii) subsequent extraction of the inorganic arsenic present in the acid medium using chloroform followed by back-extraction to acidic medium. The final detection and quantification is done by flow injection hydride generation atomic absorption spectrometry (FI-HG-AAS). The seven test items used in this exercise were reference materials covering a broad range of matrices: mussels, cabbage, seaweed (hijiki), fish protein, rice, wheat, mushrooms, with concentrations ranging from 0.074 to 7.55 mg kg(-1). The relative standard deviation for repeatability (RSDr) ranged from 4.1 to 10.3%, while the relative standard deviation for reproducibility (RSDR) ranged from 6.1 to 22.8%. (C) 2016 The Authors. Published by Elsevier Ltd. This is an open access article under the CC BY-NC-ND license (http://creativecommons.org/licenses/by-nc-nd/4.0/)

Famílies botàniques de plantes medicinals

Facultat de Farmàcia, Universitat de Barcelona. Ensenyament: Grau de Farmàcia, Assignatura: Botànica Farmacèutica, Curs: 2013-2014, Coordinadors: Joan Simon, Cèsar Blanché i Maria Bosch.Els materials que aquí es presenten són els recull de 175 treballs d’una família botànica d’interès medicinal realitzats de manera individual. Els treballs han estat realitzat per la totalitat dels estudiants dels grups M-2 i M-3 de l’assignatura Botànica Farmacèutica durant els mesos d’abril i maig del curs 2013-14. Tots els treballs s’han dut a terme a través de la plataforma de GoogleDocs i han estat tutoritzats pel professor de l’assignatura i revisats i finalment co-avaluats entre els propis estudiants. L’objectiu principal de l’activitat ha estat fomentar l’aprenentatge autònom i col·laboratiu en Botànica farmacèutica

Effects of sample processing on arsenic speciation in marine macroalgae.

The stability of arsenic species in environmental samples during sampling, storage and processing is crucial for speciation studies. Losses, interconversion and degradation of arsenocompounds can occur during these steps as a result of the interaction with the container material, microbial activity and temperature or light. In order to study the possible effects of storage and processing on arsenic compounds, subsamples of alga Cystoseira mediterranea Sauvageau were stored under different conditions (nonfrozen; frozen at 18 C for 24 h and 45 days; frozen at 80 C for 24 h and 45 days) and subjected to one of the following processing methods: chopping into fine pieces with a knife; grinding by hand in a glass mortar under N2(l); drying under an air current at room temperature (25 C); drying in an oven at 40 C; lyophilization. The total contents of arsenic and arsenic compounds were then determined in these subsamples. Non-frozen subsamples were of 150 mg As per kg while frozen-defrosted samples were of 92 mg As per kg. Nevertheless, in spite of this loss in content, the proportion of arsenic compounds was maintained in both cases. Our results indicate that freezing is an unsuitable storage method for macroalgae because losses of arsenic may occur. We recommend a drying method for this purpose

Selenium uptake by edible plants from enriched peat.

As a constituent of selenoproteins, selenium (Se) is considered an essential element for human health.The main way that Se enters the body is via the consumption of vegetables, whose concentration of thiselement depends on soil Se content. We grew cabbage, lettuce, chard and parsley, in peat enriched in Seby means of the additive Selcote Ultra®and Na2SeO3and Na2SeO4. Total Se in plants was determinedby acidic digestion and Se speciation by an enzymatic extraction. Both were measured by ICP/MS. Theconcentration ranges were between 0.1 mg Se kg−1and 30 mg Se kg−1for plants grown in Selcote Ultra®media, and between 0.4 mg Se kg−1and 1606 mg Se kg−1for those grown in peat enriched with Se sodiumsalts. We found Se (IV), Se (VI) and SeMet in all the extracts. Peat fortified with Selcote Ultra®gave slightlyhigher Se concentration than natural content values. For plants grown with selenium sodium salts, Secontent increases with the Se added and part of the inorganic Se was converted mainly to SeMet. A highSe fortification can damage or inhibit plant growth. Cabbage showed the greatest tolerance to Se

Study of selenocompounds from selenium-enriched culture of edible sprouts

Selenium is recognised as an essential micronutrient for humans and animals. One of the main sources of selenocompounds in the human diet is vegetables. Therefore, this study deals with the Se species present in different edible sprouts grown in Se-enriched media. We grew alfalfa, lentil and soy in a hydroponic system amended with soluble salts, containing the same proportion of Se, in the form of Se(VI) and Se(IV). Total Se in the sprouts was determined by acidic digestion in a microwave system and by ICP/MS. Se speciation was carried out by enzymatic extraction (Protease XIV) and measured by LC-ICP/MS. The study shows that the Se content of plants depends on the content in the growth culture, and that part of the inorganic Se was biotransformed mainly into SeMet. These results contribute to our understanding of the uptake of inorganic Se and its biotransformation by edible plants