Behaviour of glyphosate in a reservoir and the surrounding agricultural soils.

Glyphosate (GPS) is an herbicide currently used on olive crops in Spain, and can be transported to the nearby reservoirs currently used for human consumption. The purpose of this work was to study the behaviour and environmental fate of GPS in water and sediments of the Vibora Reservoir, its tributary river, and the surrounding agricultural soils to assess the risk of water pollution of this reservoir. The adsorption of GPS by different matrices was as follows: heading of the reservoir sediment (Cabecera)>tail sediment (Cola)>soils>Vibora sediment. The highest amount of oxides (especially Fe oxides) was observed in sediments from Cabecera and Cola whereas the lowest values were recorded on Vibora sediment. Results indicate that the highest GPS adsorption is due to the amorphous oxides and the edge sites of the clay minerals. Glyphosate adsorption increased with decreasing pH from 8 to 7. The desorption percentage of GPS from the four soils studied ranged only from 0.40 to 1.22%. Desorption was almost irreversible for Cabecera and Cola sediments, with values between 0 and 1.1%. Conversely, Vibora sediment presented about 20% desorption, probably due to its coarse texture and lower levels of amorphous oxides. Hockey-stick first-order kinetics was the best descriptor for water glyphosate dissipation at the Cabecera and Cola locations, and simple first-order kinetic for the water from the tributary Vibora River. The half-lives (DT50) were between 6.3 and 11.0days. The rapid degradation of GPS in surface waters and its practically irreversible sorption on these soils and sediments implies that GPS use in similar agricultural areas is of very low environmental risk. This manuscript also outlines the importance of the presence of photo-sensitizers in waters in the degradation routes of GPS in reservoirs.

Soil pollution by PAHs in urban soils: a comparison of three European cities.

The purpose of this study was to determine the degree of contamination with polycyclic aromatic hydrocarbons (PAHs) in samples of urban soil from three European cities: Glasgow (UK), Torino (Italy) and Ljubljana (Slovenia). Fifteen PAHs (naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benzo[a]anthracene, chrysene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenzo[a,h]anthracene, benzo[g,h,i]perylene, indeno[1,2,3-c,d]pyrene) were measured in urban soil samples, using harmonised sampling, sample extraction and analyte quantification methods. Although the mean concentration of each PAH in urban soils of each city showed a wide range of values, high levels of contamination were only evident in Glasgow, where the sum of concentrations of 15 PAHs was in the range 1487-51,822 microg kg(-1), cf. ranges in the other two cities were about ten-fold lower (89.5-4488 microg kg(-1)). The three predominant PAHs were phenanthrene, fluoranthene and pyrene, with the sum of these compounds about 40% of the total PAH content. These data, together with some special molecular indices based on ratios of selected PAHs, suggest pyrogenic origins, especially motor vehicle exhausts, to be the major sources of PAHs in urban soils of the three cities. The largest concentrations for PAHs were often found in sites close to the historic quarters of the cities. Overall, the different climatic conditions, the organic carbon contents of soil, and the source apportionment were the dominant factors affecting accumulation of PAHs in soil.

Reduction of availability of trace metals in urban soils using inorganic amendments.

Urban soils in medium- and large-sized cities generally have shown elevated contents of environmentally important trace metals (e.g. lead, copper, zinc). Such high concentrations in soils of green areas, mainly recreational areas, can be a source of potentially toxic elements and pose a risk for human health. Thus the availability of these contaminants is an essential control parameter, as it indicates potential plant uptake and their transfer to humans via inhalation of suspended dust, or direct ingestion (i.e. hand to mouth pathway), or consumption of contaminated foodstuff. Young children are the most sensitive segment of the population. Addition of amendments to the soil is a feasible technique to reduce the availability of trace metals. Accordingly, four urban soils of green areas of Seville (Spain), with relatively high lead contents and moderate copper and zinc contents, were amended in the laboratory with four inorganic materials [acid zeolite (AZ), sodium zeolite (SZ), Slovakite (SL), apatite (AP)], at two rates (1%, 5% w/w) and incubated for 1 year. Significant decreases in EDTA-extractable metal contents were observed in some of the treatments after adding the amendments even before the incubation begun, mainly for SL treatments. The amendment that produced the longest lasting immobilisation effect, compared to control treatments, was AZ at the higher rate. The effects of SZ and SL tended to decrease with time, while the AP effect was almost negligible after 3 months of ageing. This study confirms the feasibility of using certain inexpensive soil amendments to at least temporarily immobilise metals in urban soils for the purpose of protecting human health, especially that of young children.

Analgesia domiciliario con infusores subcutáneos / Analgesia unit subcutaneous pumas at home

OBJETIVO: Evaluar la efectividad y seguridad del uso de un sistema de bomba elastomérica con una solución de Ketorolaco 270 mg y Tramadol 300 mg en suero fisiológico por vía subcutánea a 1 ml/hora en el tratamiento del dolor postoperatorio moderado-severo en Cirugía Ambulatoria Ortopédica. MATERIAL Y MÉTODOS: Se realiza un estudio retrospectivo sobre 250 pacientes sometidos a diversas intervenciones de Cirugía Ortopédica Ambulatoria. Después de la intervención son conectados al infusor subcutáneo Multitrate 2C1154K (Baxter®) con la pauta propuesta durante tres días. Los parámetros analizados son: Score Telefónico basado en estado general, dolor, sangrado, tolerancia, cumplimiento del tratamiento, fiebre > a 38º C y estado de la herida. Según el Score Telefónico obtenido la evolución se clasifica en Grupo I: evolución normal, correcto nivel de analgesia y buen estado general del paciente; Grupo II: necesidad de nueva llamada y Grupo III: necesita atención médica. Se evalúa la necesidad de analgesia de rescate y la descripción de los efectos secundarios. RESULTADOS: Llamadas del Grupo I: 95,2%; Grupo II: 4%; llamadas del Grupo III: 0,8%. Necesidad de analgesia de rescate: 12,2%. Efectos secundarios: mareo: 1,7%; cefalea 1,4%; vómitos: 1,4%; náuseas: 0,8%; picor: 0,8%; sueño: 0,8%; arrancado 0,5%; no efectos secundarios: 92,6%. CONCLUSIONES: El uso de analgesia invasiva domiciliaria por vía subcutánea, mediante una infusión de 1 ml/hora de una mezcla de Ketorolaco y Tramadol es eficaz y seguro para el control del dolor moderado-severo en Cirugía Ortopédica Ambulatoria (AU)

AIM: To evaluate the feasibility and security of the use of an elastomeric pump with 270 mg of Ketorolac and 300 mg of Tramadol in a saline solution for subcutaneous administration at a rate of 1 ml/hour for analgesic treatment of moderate pain in Orthopaedic Ambulatory Surgery. MATERIAL AND METHODS: A retrospective study with 250 patients was performed. At the end of surgery, Multitrate 2C1154K (Baxter®) subcutaneous infusor was connected for three days. We analysed a Phone Score based on: general status, pain level, bleeding, diet, treatment fulfillment, fever > 38º C and satisfactory wound evolution. According to the Phone Score obtained we divided the evolution into three groups: Group I: normal evolution, correct level of analgesia and good general state of patient; Group II: new call needed; Group III: medical treatment needed. Supplemental oral analgesia and secondary effects were also evaluated. RESULTS: (95.2%) of calls were in Group I; (4%) were in Group II and (0.8%) in Group III. The need of supplemental oral analgesia was 12.2%. The secondary effects observed were: dizziness: (1.7%); headache: (1.4%); vomiting: (1.4%); nausea: (0.8%); itching: (0.8%); drowsiness: (0.8%); accidental removal: (0.5%); no secondary effects: (92.6%). CONCLUSION: the use of the elastomeric pump Multitrate 2C1154K (Baxter®) for subcutaneous administration of Ketorolac 270 mg and Tramadol 300 mg at 1 ml/hour ratio is useful and safe for moderate postoperative pain control in Orthopaedic Ambulatory Surgery (AU)

Copper and zinc retention by an organically amended soil.

This paper describes changes in retention of Cu and Zn in laboratory experiments by a sandy soil that had been amended in the field with different composted wastes. The amounts of the metals retained increased as a result of the amendments, especially after two years. Desorption of the sorbed metals was always negligible, regardless of the treatment. The proportion of Cu retained was considerably higher than that of Zn, suggesting a higher affinity of the soil for the former. The greater sorption in the amended soils indicates a build-up of fresh sites for metal retention. The use of 'log(activity) vs. pH' plots showed that the nature of the surfaces retaining metals on the untreated and amended soils is different. At comparable pH values, the amended soils gave higher solution metal concentrations. Some of the possible environmental consequences of the use of these amendments for remediation purposes are discussed.

The effect of dissolved glyphosate upon the sorption of copper by three selected soils.

The effect of the pesticide glyphosate (GPS) on adsorption processes of copper onto three soils of different characteristics has been studied. Cu adsorption decreases in general with increasing GPS concentration in solution, due principally to the lower equilibrium pHs, although this is not the only variable affecting copper adsorption. For the same pH values, Cu adsorption is higher in two of the three soils in the presence of GPS, but for the third soil, Cu adsorption is higher in the absence of GPS. This behavior is explained by the possibility of GPS adsorption on these soils and by the formation of Cu-GPS complexes in solution. The soils showing a higher Cu adsorption in the presence of GPS than in its absence for the same pH are able to adsorb this pesticide. In these soils, copper can be adsorbed directly on the soil surfaces, and also through the formation of bonds with GPS previously adsorbed. The third soil was not able to adsorb GPS. Consequently, all the pesticide remained in solution, forming strong Cu complexes with low tendency to be adsorbed on this soil. For this reason, the concentration of free Cu in solution is drastically reduced, and the adsorption of copper on this soil is lower.

Ethyl cellulose polymer microspheres for controlled release of norfluazon.

The pesticide norfluazon has been microencapsulated using ethyl cellulose to develop controlled-release formulations that decrease its mobility through the soil and protect it from photodegradation. Ethyl cellulose microspheres loaded with norfluazon were prepared by the solvent-evaporation method. To obtain the microspheres, certain conditions (pesticide/polymer ratio, percentage of emulsifying agent and solvent) were varied. The shape and size of the microspheres obtained were studied by scanning electron microscopy. Other parameters, such as solids recovery, encapsulation efficiency and pesticide loading, were also studied. The release rate of norfluazon from the different microspheres was slower than that of pure norfluazon. In particular, microspheres obtained with o-xylene, which provided the largest diameter, retarded the initial release of the pesticide relative to microspheres obtained with chloroform, or to pure norfluazon. Moreover, the studies showed that the pesticide/polymer ratio controlled the release of norfluazon, which was slower when this ratio was low. Release rates conformed to a generalised kinetic equation for a diffusion-controlled release mechanism, and the time taken for 50% of the active ingredient to be released into water, t50, was calculated.

Glyphosate adsorption on soils of different characteristics. Influence of copper addition.

Results of glyphosate (GPS) adsorption on three soils of different characteristics show that the interaction of this pesticide with the soils was not related to their CEC and clay minerals content, but to the content of iron and aluminum amorphous oxides and organic matter. The presence of Cu in treatment solutions enhanced GPS adsorption, due to several reasons: GPS coordinates strongly to Cu, and Cu GPS complexes formed seem to have higher ability to be adsorbed on the soil than free GPS; GPS adsorption can take place on sites where Cu was previously adsorbed, acting as a bridge between the soil and GPS; when Cu was present the solution pH decreased, and GPS adsorption increased, since lower pHs lead to the formation of GPS species with lower negative charge, which are adsorbed more easily on the negatively charged soil surfaces.