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1.
Environ Geochem Health ; 45(12): 9215-9230, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37209325

RESUMO

Mining activity is one of the main sources to pollute soil, water and plants. An analysis of soil and plant samples around the Atrevida mining area in Catalonia (NE Spain) was preformed to determine potentially harmful elements (PHEs). Soil and plant samples were taken at eight locations around the mining area. The topsoil (0-15 cm) samples were analysed for physico-chemical properties by standard methods, by ICP-MS for Cd, Co, Cr, Cu, Fe, Ni, Pb and Zn, and were microwave-digested. Plant, root and shoot samples were digested separately, and heavy metals were analysed by AAS. Translocation factor (TF), biological concentration factor (BCF) and biological accumulation factor (BAF) were determined to assess the tolerance strategies developed by native species and to evaluate their potential for phytoremediation purposes. Soil pH was generally acid (5.48-6.72), with high soil organic matter (SOM) content and a sandy loamy or loamy texture. According to the agricultural soil values in southern Europe, our PHEs concentrations exceeded the toxicity thresholds. The highest root content of the most studied PHEs appeared in Thymus vulgaris L. and Festuca ovina L., while Biscutella laevigata L. accumulated more PHEs in shoots. The TF values were > 1 in B. laevigata L., but BAF obtained < 1, except Pb. B. laevigata L., and can be considered potentially useful for phytoremediation for having the capacity to restrict the accumulation of large PHEs amounts in roots and Pb translocation to shoots.


Assuntos
Metais Pesados , Poluentes do Solo , Solo/química , Espanha , Chumbo/toxicidade , Chumbo/análise , Poluentes do Solo/análise , Metais Pesados/toxicidade , Metais Pesados/análise , Plantas , Monitoramento Ambiental
2.
Environ Pollut ; 196: 156-63, 2015 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-25463709

RESUMO

Historical trends in trace element deposition were analyzed using herbaria specimens. We determined Al, Fe, Mg, Mn, Ca, Na, P, K, S, As, Cd, Cr, Cu, Ni, Pb and Zn contents in leaves of eight specimens collected in 1941. To assess changes, we collected the same plants from a botanical garden in 2012. The concentrations of major elements showed large species variability. However, temporal trends were predominately detected for heavy metals. The Cd, Ni and Cr contents in the 2012 leaves were 10, 13 and 16 times higher, respectively, than in 1941. Urban activities have substantially raised the levels of these metals in urban atmospheres due to changes in human activities over 70 years of urban growth. Nevertheless, Pb has decreased (126%) in recent decades thanks to controlled lead fuel combustion. In short, metal deposition trend to increase Cr, Ni and Cd levels.


Assuntos
Cidades/estatística & dados numéricos , Monitoramento Ambiental/métodos , Poluição Ambiental/estatística & dados numéricos , Metais Pesados/análise , Crescimento Demográfico , Humanos , Metais , Oligoelementos/análise
3.
Eur J Cancer ; 36(16): 2069-75, 2000 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-11044643

RESUMO

The aim of this study was to prospectively evaluate the diagnostic contribution of the detection of K-ras mutation and measurement of serum CA 19.9 concentrations to cytological diagnosis in patients with clinical suspicion of pancreatic cancer. These patients had either the presence or absence of a pancreatic mass as determined by imaging procedures. A total of 156 consecutive patients with clinical suspicion of pancreatic cancer or for confirmation and follow-up of their chronic pancreatitis disease were included: 84 patients presenting a pancreatic mass (group 1) and 72 patients without a pancreatic mass (group 2). K-ras mutations were detected by a restriction fragment length polymorphism/polymerase chain reaction (RFLP/PCR) method and CA 19.9 by an immunoluminometric assay. When a pancreatic mass was present, cytology offered a high sensitivity, but with a significant number of inconclusive results and K-ras mutational analysis offered a highly specific test. In the absence of a pancreatic mass, CA 19.9 (cut-off 100 U/ml) increased the sensitivity of the diagnosis by cytology and K-ras mutational analysis did not add significant information. Thus both tests contribute to the clinical decision process when pancreatic cancer is clinically suspected and the cytological report is not conclusive.


Assuntos
Biomarcadores Tumorais/sangue , Antígeno CA-19-9/sangue , Genes ras/genética , Mutação/genética , Neoplasias Pancreáticas/diagnóstico , Adulto , Idoso , Idoso de 80 Anos ou mais , Biópsia por Agulha/métodos , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias Pancreáticas/sangue , Estudos Prospectivos , Sensibilidade e Especificidade
4.
Surg Endosc ; 16(2): 234-9, 2002 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-11967670

RESUMO

BACKGROUND: Hand-assisted laparoscopic surgery (HALS) represents a useful alternative to conventional laparoscopic surgery (LS). Its potential advantages--(a quicker, safer procedure and less need to convert to open surgery) are due to the recovery of tactile feedback. However, HALS requires the performance of a mini-laparotomy when surgery commences, and the wound is stretched and compressed throughout the procedure. In addition, it is associated with a more intense manipulation of the intraabdominal viscera. All of these factors increase the surgical trauma, it is not known whether HALS maintains the minimally invasive characteristics of conventional LS. Therefore, we set out to study the applicability, immediate clinical outcome, inflammatory response, and cost of HALS compared with conventional LS using colectomy as a model. METHODS: We performed a prospective randomized trial comparing laparoscopic-assisted colectomy with HAL colectomy. The aims of the study were to assess (a) perioperative features, including time, advantages, and conversion; (b) the patient's immediate clinical response, including recovery of bowel sounds, refeeding time, postoperative pain, local and general morbidity, and hospital stay; (c) the effect on the inflammatory response, using interleukin-6 (ILG) and C-reactive protein (CRP) measurements; (d) oncological issues, including intraoperative cytology and features of the specimen; and (d) the relative costs of the two procedures. RESULTS: A total of 54 patients were enrolled in the study, 27 laparoscopic and 27 HALS. The operative times were similar, but HALS was associated with a far lower conversion rate--7% vs 23%. Immediate clinical outcomes, oncological features, and costs were similar for the two procedures, but HALS was associated with a significantly greater increase in IL6 and CRP than the conventional laparoscopic procedure. CONCLUSION: This comparative study shows that HALS simplifies difficult intraoperative situations, reducing the need for conversion. Although it is a more aggressive procedure, HALS preserves the features of a minimally invasive approach, maintains all of the oncological features of conventional laparoscopic surgery, and does not increase the cost. HALS should therefore be considered as a useful adjunct when difficult situations arise during conventional laparoscopic colectomy.


Assuntos
Colectomia/métodos , Laparoscopia/métodos , Idoso , Idoso de 80 Anos ou mais , Índice de Massa Corporal , Colectomia/efeitos adversos , Colectomia/economia , Colectomia/estatística & dados numéricos , Feminino , Humanos , Inflamação/etiologia , Período Intraoperatório , Laparoscopia/efeitos adversos , Laparoscopia/economia , Laparoscopia/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Complicações Pós-Operatórias/etiologia , Estudos Prospectivos , Resultado do Tratamento
5.
Environ Pollut ; 92(1): 19-25, 1996.
Artigo em Inglês | MEDLINE | ID: mdl-15091407

RESUMO

The concentrations of Cd, Co, Cu, Ni, Pb, Zn, Fe and Mn in different inorganic fertilizers (urea, calcium superphosphate, iron sulphate and copper sulphate) and in pesticides (two herbicides and one fungicide) are evaluated together with the contribution of these metals in soils from their use. The study was made in rice farming areas to the north of Albufera Natural Park (Valencia, Spain). The results obtained show that superphosphate is the fertilizer that contains the highest concentrations of Cd, Co, Cu and Zn as impurities. Copper sulphate and iron sulphate have the most significant concentrations of Pb, and are the only fertilizers in which Ni was detected. The three pesticides analysed show similar Cd contents and the highest levels of Fe, Mn, Zn, Pb and Ni are found in the herbicides. The most significant additions of heavy metals as impurities that soil receives from agricultural practices, are Mn, Zn, Co and Pb. Three contamination indexes have been applied to provide a basis for comparison of potential heavy metal toxicity. These results denote the potential toxicity of heavy metals in the studied soils.

6.
Chemosphere ; 55(7): 1027-34, 2004 May.
Artigo em Inglês | MEDLINE | ID: mdl-15051371

RESUMO

This study determines total levels of three (Cd, Pb and Ni) potentially toxic trace elements in western Almería (Spain) greenhouse surface soil horizons using microwave digestion; it establishes the geochemical baseline concentration, and it investigates possible relationships between soil properties and elemental concentrations. The results show that the soil concentration of these heavy metals is lower than mentioned in the European and Spanish normative, but they are higher than those reported by other authors working on agricultural soils. The obtained geochemical baseline concentrations (mg kg(-1)) were: Cd 0.4-0.8, Pb 2.5-89.9 and Ni 16.1-30.7. Using the upper baseline criterion, 88% of greenhouse soils have relatively higher content of heavy metals because of their Cd, Pb and Ni concentration. Moreover, soil properties are related to heavy metals contents suggesting that among Cd, Pb and Ni have a similar origin and those total metal concentrations are controlled primarily by soil compositions.


Assuntos
Agricultura , Ambiente Controlado , Metais Pesados/análise , Solo/análise , Micro-Ondas , Espanha , Espectrofotometria Atômica
7.
Chemosphere ; 46(2): 355-69, 2002 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-11827296

RESUMO

The toxic effects of waters collected from irrigation channels in a Mediterranean wetland (Albufera Natural Park, Valencia, Spain) were tested with the Microtox assay and compared with six pollution indices (PIs) defined from analytical parameters. Chemical oxygen demand (COD), biological oxygen demand (BOD), nutrients, heavy metals and pesticides were measured. The bioassay result (concentrations of the water sample (% V/V) that reduced light emission to 10%, 20% and 50%, EC10, EC20 and EC50, respectively (ECs)) was compared with the PIs. This comparison has demonstrated a general agreement between ECs and PIs, except in the case of irrigation channels affected by herbicides used in rice farming (molinate and thiobencarb). No pronounced inhibition was detected in the bioluminescence in relation to the eutrophic parameters in the irrigation waters for EC50 values, indicating that this parameter does not suffice to detect eutrophic waters. Data derived from irrigation water pollution and bioassay were assembled by multivariate statistical techniques (principal component analysis). These components were associated with various contamination sources.


Assuntos
Eutrofização , Metais Pesados/toxicidade , Praguicidas/toxicidade , Vibrio/efeitos dos fármacos , Poluentes da Água/toxicidade , Agricultura , Bioensaio/métodos , Dose Letal Mediana , Região do Mediterrâneo , Oxigênio/metabolismo , Espanha , Abastecimento de Água
8.
Chemosphere ; 84(1): 1-8, 2011 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-21392813

RESUMO

Heavy metals have become one of the most serious anthropogenic stressors for plants and other living organisms. Having efficient and feasible bioassays available to assess the ecotoxicological risks deriving from soil pollution is necessary. This work determines pollution by Cd, Co, Cr, Cu, Ni, Pb, V and Zn in two soils used for growing rice from the Albufera Natural Park in Valencia (Spain). Both were submitted to a different degree of anthropic activity, and their ecotoxicological risk was assessed by four ecotoxicity tests to compare their effectiveness: Microtox test, Zucconi test, pot bioassay (PB) and soil plate bioassay (SPB). The sensitivity of three plant species (barley, cress and lettuce) was also assessed. The results reveal a different degree of effectiveness and level of inhibition in the target organisms' growth depending on the test applied, to such an extent that the one-way analysis of variance showed significant differences only for the plate bioassay results, with considerable inhibition of root and shoot elongation in seedlings. Of the three plant species selected, lettuce was the most sensitive species to toxic effects, followed by cress and barley. Finally, the results also indicate that the SPB is an efficient, simple and economic alternative to other ecotoxicological assays to assess toxicity risks deriving from soil pollution.


Assuntos
Monitoramento Ambiental/métodos , Metais Pesados/toxicidade , Poluentes do Solo/toxicidade , Bioensaio , Brassicaceae/efeitos dos fármacos , Ecotoxicologia , Hordeum/efeitos dos fármacos , Lactuca/efeitos dos fármacos , Medição de Risco , Solo/química
9.
Chemosphere ; 78(4): 409-15, 2010 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-20004461

RESUMO

This paper provides the first available information on the determination of the total mercury content in different Mediterranean calcareous soils by thermal decomposition, amalgamation and atomic absorption spectrophotometry. Fifty-three samples from five soil use groups (natural, dry land, greenhouse, irrigated and rice farming soils) were analysed. The results show that the levels of mercury in these soils were 9.4-1585mugkg(-1). Soil organic matter and the zinc equivalent index have been related to Hg content in soils, suggesting that Cu, Ni, Zn and Hg are of a similar origin. The background level (BL), geochemical baseline concentrations (GBC) and the reference value (RV) were established from natural soils. Calculations are according to the log-normal distribution criterion. The BL, GBC and RV values obtained were 25.1, 9.8-64.3, and 64.3mugkg(-1), respectively. The BL was similar to the baseline concentration in soils obtained at Admiralty Bay (Antarctica) (24.6mugkg(-1)) and a Spanish peat bog (Galicia) (22mugkg(-1)). These data show that rice farming soils (gleyic-calcaric Fluvisols, Fluvaquents), irrigated soils (calcaric Fluvisols, Xerofluvents) and some greenhouse soils (cumulic Antrosols) presented much higher levels, indicating contamination. Hg accumulation in these soils was associated with local anthropogenic sources.


Assuntos
Carbonato de Cálcio/química , Mercúrio/análise , Poluentes do Solo/análise , Solo/análise , Poluentes Químicos da Água/análise , Monitoramento Ambiental , Oryza/química , Poluentes do Solo/química , Poluentes Químicos da Água/química
10.
Chemosphere ; 75(6): 781-7, 2009 May.
Artigo em Inglês | MEDLINE | ID: mdl-19187949

RESUMO

Composting organic residue is an interesting alternative to recycling waste as the compost obtained may be used as organic fertilizer. This study aims to assess the composting process of rice straw and sewage sludge on a pilot-scale, to evaluate both the quality of the composts obtained and the effects of applying such compost on soil properties and plant development in pot experiments. Two piles, with shredded and non-shredded rice straw, were composted as static piles with passive aeration. Throughout the composting process, a number of parameters were determined, e.g. colour, temperature, moisture, pH, electrical conductivity, organic matter, C/N ratio, humification index, cation exchange capacity, chemical oxygen demand, and germination index. Moreover, sandy and clayey soils were amended with different doses of mature compost and strewed with barley in pot experiments. The results show that compost made from shredded rice straw reached the temperatures required to maximise product sanitisation, and that the parameters indicating compost maturity were all positive; however, the humification index and NH(4) content were more selective. Therefore, using compost-amended soils at a dose of 34 Mg ha(-1) for sandy soil, and of 11 Mg ha(-1) for clayey soil improves soil properties and the growth of Hordeum vulgare plants. Under there conditions, the only limiting factor of agronomic compost utilisation was the increased soil salinity.


Assuntos
Agricultura/métodos , Conservação dos Recursos Naturais/métodos , Oryza , Caules de Planta , Esgotos , Solo , Gerenciamento de Resíduos/métodos
11.
Arch Environ Contam Toxicol ; 44(2): 141-51, 2003 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-12520386

RESUMO

It is known that the sources of soil contamination can be endogenous or exogenous and that exogenous contamination may be direct or indirect. In this work, an environmental pesticide fate study was conducted in soil profiles collected from 23 rice field sites in an important Mediterranean wetland (Albufera Natural Park, Valencia, Spain) from April 1996 to November 1997. Temporal and spatial distribution of 44 pesticide residues in an alluvial Mediterranean soil (gleyic-calcaric Fluvisol, Fluvaquent) were monitored. During this period, the levels of pesticide residues in different soil horizons (Ap1 0-12 cm, Ap2 12-30 cm, ApCg 30-50 cm, C1gr 50-76 cm, and C2r 76-100 cm) were investigated. In addition, information was collected on agricultural pesticide application practices and soil characteristics. Distribution throughout the soil profile showed that pesticide concentrations were always higher in the topsoil (Ap1 horizon), in the autumn season, and in the border with citrus-vegetable orchard soils (calcaric Fluvisol, Xerofluvent). Chlorpyrifos (organophosphorus), endosulfan (organochlorine), and pyridaphenthion (organophosphorus) insecticides were, respectively, the most detected of all the pesticides investigated. These results were associated with processes, such as nonleaching, transport by movement into surface waters, retention, volatilization, and chemical and biological degradation in the topsoil, as well as with direct and indirect exogenous contamination sources.


Assuntos
Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Agricultura , Monitoramento Ambiental , Oryza , Estações do Ano , Espanha
12.
Arch Environ Contam Toxicol ; 32(4): 346-52, 1997 May.
Artigo em Inglês | MEDLINE | ID: mdl-9175498

RESUMO

An environmental fate study was conducted in a citrus orchard plot in València (Spain) in the fall of 1993. Dissipation and distribution of atrazine, simazine, chlorpyrifos and tetradifon residues following their controlled addition for agricultural purposes in a mediterranean red soil (Luvic Calcisol, Rhodoxeralf) were evaluated. During a two-month period, the amounts of applied pesticides in different soil layers (0-0.05, 0.05-0.22, 0.22-0.42, and 0.42-0.52 m) were monitored. In addition, information on soils, weather and agricultural practice were collected. Degradation half-lives were calculated, assuming zero-order kinetics: 11 days for atrazine, 12 days for simazine, 10 days for chlorpyrifos, and 18 for tetradifon. The distribution through the soil profile shows that the pesticide concentrations were always highest in the upper layer (0-0.05 m) of soil, and that atrazine was the most mobile of all the four pesticides investigated.


Assuntos
Clorpirifos/análise , Frutas , Hidrocarbonetos Clorados/análise , Inseticidas/análise , Resíduos de Praguicidas/análise , Poluentes do Solo/análise , Triazinas/análise , Cromatografia Gasosa , Monitoramento Ambiental , Solo/análise , Água , Tempo (Meteorologia)
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