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1.
Mar Pollut Bull ; 196: 115644, 2023 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-37922592

RESUMEN

This study aimed to assess the presence of 21 UVFs and metabolites in coastal regions of the Iberian Peninsula, to evaluate their environmental risk, and identify possible influential factors affecting their measured concentrations. Sampling was carried out in spring and summer to assess possible seasonal variations. UVFs were detected in 43 of the 46 sampling sites. Only 5 were found above LOD: BP4, OC, BP3 and metabolites BP1 and BP8. Samples collected in Mar Menor had the greatest variety of compounds per sample and the highest cumulative concentrations. The risk was characterized using Risk Quotients (RQ). BP1 showed a Low environmental Risk in 2 sites while for OC the RQ indicated a Moderate Risk in 22 points. The variables that contribute most to the variation are population density, sampling season, whether it was an open bay or not, and level of urbanization. The presence of WWTPs had a lower influence.


Asunto(s)
Contaminantes Químicos del Agua , Contaminantes Químicos del Agua/análisis , Monitoreo del Ambiente , Medición de Riesgo
2.
Eur Arch Otorhinolaryngol ; 280(7): 3177-3185, 2023 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-36806910

RESUMEN

PURPOSE: To evaluate the efficacy of ossicular chain reconstruction (OCR) in primary and revision surgeries, and to investigate the impact of the number of previous surgeries on hearing outcomes. METHODS: Retrospective analysis of cases with OCR due to chronic otitis in a tertiary center between January 2018 and September 2021. RESULTS: Altogether, 147 cases of ossicle involvement were assessed. In 91.83% (n = 135) OCR was performed, 96.26% of them with titanium TORP/PORP (n = 130), two cases with autologous prosthesis and three with piston. Mean follow-up was 8.8 months. The ABG significantly improved in the total group (TORP/PORP) from a mean (SD) of 30.94 (15.55) to 19.76 (13.36) dB (p < 0.0001) with 60.86% success. The best results were achieved in primary OCR with PORP implantation without cholesteatoma (89.47%). Primary cases have a significantly higher success rate in contrary to revision surgeries (72.27%, vs. 52.00%, p = 0.032). The only relevant predictive factor proved to be the fact of revision (p = 0.029). A statistically significant correlation between the number of previous surgeries and hearing results could not be proved. There was no difference in hearing outcomes between patients with only one or more than one previous surgeries in the revision groups. Neither the presence of cholesteatoma, nor the type of OCR (TOPR/PORP) and the indication of revision had an impact on postoperative ABG. CONCLUSIONS: Titanium prostheses are effective in OCR both in primary and revision cases. It is not the number of previous surgeries, but the fact of revision that influences postoperative hearing results.


Asunto(s)
Colesteatoma del Oído Medio , Prótesis Osicular , Reemplazo Osicular , Humanos , Reemplazo Osicular/métodos , Estudios Retrospectivos , Titanio , Resultado del Tratamiento , Audición , Timpanoplastia/métodos , Colesteatoma del Oído Medio/cirugía
4.
Chemosphere ; 310: 136894, 2023 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-36265710

RESUMEN

The bioaccumulation potential of spherical and rod-shaped CuO nanomaterials (NMs) was assessed in rainbow trout (Oncorhynchus mykiss) exposed via water and diet following the OECD Test Guideline No. 305. Fish were exposed via diet to both NMs at concentrations of 70 and 500 mg Cu/kg for 15 days, followed by 44 days of depuration. For water-borne exposure, only the rod-shaped CuO NMs were tested at 0.08 and 0.8 mg Cu/L for 28 days, followed by 14 days of depuration. The concentration of Cu was determined in fish whole body to derive biomagnification and bioconcentration factors (BMF and BCF). Different tissues were sampled to investigate the total Cu biodistribution and target organs as well as the particle number-based bioaccumulation of CuO NMs. Estimated BMF and BCF values were below the thresholds of concern. However, shape and route influenced depuration. Following dietary exposure, there was a higher depuration of Cu from fish exposed to the rod-shaped compared to the spherical CuO NMs. A higher depuration was also observed for rod-shaped CuO NMs following the dietary exposure compared the aqueous one. Despite the much higher dietary exposure concentrations of rod-shape CuO NMs, similar Cu body burdens were reached via water. Cu was found in particulate form in different tissues. Although these NMs had a low bioaccumulation potential, differences in distribution and elimination patterns of Cu were observed depending on the exposure route and particle shape. Careful consideration of the most relevant exposure route is needed when designing a bioaccumulation experiment for testing NMs.


Asunto(s)
Nanoestructuras , Oncorhynchus mykiss , Contaminantes Químicos del Agua , Animales , Bioacumulación , Distribución Tisular , Contaminantes Químicos del Agua/análisis , Cobre , Agua
5.
Aquat Toxicol ; 251: 106291, 2022 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-36099779

RESUMEN

The potential toxicity deriving from the interaction between chemicals and manufactured nanoparticles (NPs) represents an emerging threat to the environment and human health. Several studies have focused on the risks and (eco)toxicity of manufactured NPs as a consequence of their extensive use in recent years, however, there is still a limited understanding of the combined effects caused by manufactured NPs in the presence of other environmental contaminants. This is particularly relevant to aquatic environments, where many types of pollutants are inevitably released and can be involved in many kinds of reactions. In this context, the interaction between catecholate type ligands and two different nanomaterials, namely TiO2 and Fe2O3 NPs, was investigated by performing cytotoxicity assays with the topminnow fish hepatoma cell line (PLHC-1) using: i) the original organic molecules, ii) pristine NPs alone, and iii) modified NPs obtained by grafting the ligands on the NPs surface. Cytotoxic effects were explored at three different levels, specifically on cellular metabolism, membrane integrity and lysosomal activity. The outcomes from these assays showed cytotoxicity only for the free catechol type ligands, while in general no significant decrease in cell viability was observed for pristine NPs, as well as for the modified NPs, regardless the initial cytotoxicity level of the organic ligands These results suggest that the binding of catechols on the NPs' surface inhibited their cytotoxicity, indicating that TiO2 and Fe2O3 NPs may act as sorbents of these contaminants, thus reducing their possible detrimental effects.


Asunto(s)
Contaminantes Ambientales , Nanopartículas del Metal , Nanopartículas , Contaminantes Químicos del Agua , Animales , Catecoles/toxicidad , Humanos , Nanopartículas del Metal/toxicidad , Nanopartículas/química , Nanopartículas/toxicidad , Titanio/química , Contaminantes Químicos del Agua/toxicidad
6.
Ecotoxicol Environ Saf ; 231: 113227, 2022 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35077996

RESUMEN

As a consequence of increasing production and use of graphene-related materials (GRM), their release into the aquatic environment is likely to be expected. Development of appropriate model systems to assess their potential toxicity toward aquatic organisms is undoubtedly needed. Of particular relevance are primary cultures of fish hepatocytes, since they maintain similar functionalities as those of the original tissue. Isolated hepatocytes from rainbow trout (Oncorhynchus mykiss) were exposed to ranges of concentrations of different forms of GRM, two graphene oxides (GO) of sheet-like structure and one tubular-shaped carbon nanofiber (CNF) in the presence or absence of fetal bovine serum (FBS) for 24 and 72 h. Metabolic activity, cell membrane integrity, lysosomal function, reactive oxygen species (ROS) formation and interaction with cytochrome P450 1 A enzyme were assessed by using AlamarBlue, 5-carboxyfluorescein diacetate-acetoxymethyl ester, neutral red uptake, dichlorofluorescein and 7-ethoxyresorufin-O-deethylase (EROD) assays, respectively. In the presence of FBS, GO affected metabolic activity and cell membrane integrity more than CNF, whilst absence of serum further reduced cell viability in GRM-exposed cells. GRM did not alter lysosomal function nor did it induce ROS formation or EROD activity. Intracellular uptake was observed only in the case of CNF when incubated without FBS. Primary hepatocytes from rainbow trout appear to be a suitable model to screen for cytotoxicity and to reveal any interaction with GRM. Results emphasize the role of serum proteins in the toxicological responses following exposure to GRM with important implications for the environmental risk assessment of these nanomaterials.


Asunto(s)
Grafito , Oncorhynchus mykiss , Animales , Citocromo P-450 CYP1A1 , Grafito/toxicidad , Hepatocitos , Especies Reactivas de Oxígeno
7.
Auris Nasus Larynx ; 48(4): 630-635, 2021 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-33303286

RESUMEN

OBJECTIVE: Non-echo planar diffusion weighted magnetic resonance imaging is a reliable surveillance tool of residual cholesteatoma nowadays. It is not known whether the material of the ossicular chain prosthesis modifies the sensitivity and specificity of MRI in these cases. The aim of the study was to compare the sensitivity, specificity and a localization-specific accuracy of non-EPI DW MRI sequences for residual cholesteatoma in the following 3 subgroups: patients with titanium ossicular prosthesis (group T), with autologous cortical bone columella (group A) or without any reconstruction (group WR) of hearing bones. METHODS: This prospective study covered 28 cases with cholesteatoma of the middle ear undergone second-look surgery, who had preoperative PROPELLER DW-MRI. Surgical findings were compared to the results of the DWI-MRI. RESULTS: The overall sensitivity, specificity, positive predictive value (PPV) and negative predictive value (NPV) were: 0.76-0.8-0.76-0.8. Group T, group A and group WR sensitivity was 0.83-0.6-1, specificity: 0.75-0.75-0.85, PPV: 0.83-0.75-0.66, NPV: 0.75-0.6-1. Overall accuracy was 0.78. Size of missed cholesteatoma was 2-4 mm (mean: 2.66±1.15). CONCLUSIONS: Various materials are suitable for ossicular chain reconstruction. The poor detectability of residual or recurrent cholesteatoma in the middle ears reconstructed with autologous bony prosthesis may still claim second-look surgery instead of the usage of non- EPI DWI sequences independently in these patients.


Asunto(s)
Colesteatoma del Oído Medio/diagnóstico por imagen , Osículos del Oído/cirugía , Oído Medio/diagnóstico por imagen , Adulto , Audiometría de Tonos Puros , Umbral Auditivo , Colesteatoma del Oído Medio/cirugía , Imagen de Difusión por Resonancia Magnética , Oído Medio/patología , Femenino , Humanos , Masculino , Valor Predictivo de las Pruebas , Estudios Prospectivos , Prótesis e Implantes , Segunda Cirugía , Sensibilidad y Especificidad
8.
Environ Toxicol Chem ; 38(10): 2314-2325, 2019 10.
Artículo en Inglés | MEDLINE | ID: mdl-31343769

RESUMEN

Manufactured nanomaterial production is outpacing the ability to investigate environmental hazard using current regulatory paradigms, causing a backlog of materials requiring testing. To ameliorate this issue, regulatory bodies have proposed integrating safety into the production of novel nanomaterials, allowing for hazards to be identified early in development rather than aftermarket release. In addition, there is a growing interest in short-term ecotoxicity testing to rapidly identify environmental hazards. In this sense, the present study investigated 3 carbon nanofibers (CNFs), created with different production methods, using short-term in vitro and in vivo exposures on fish cell lines, mussel hemocytes, crustacea, and algae. The present study investigated if differences in ecotoxicity hazard between the CNFs could be identified and, if so, which product could be considered less hazardous. A major challenge in assessing the potential hazards posed by manufactured nanomaterials is standardizing the preparation for testing. Standardized operating protocols have been proposed using protein to facilitate the preparation of stable stock suspension, which is not environmentally representative. As such, the study also assessed the potential impacts these standardized protocols (with or without the use of protein) could have on the interpretation of environmental hazard. The results demonstrated that there were clear differences between the 3 CNFs and that the dispersion protocol influenced the interpretation of hazard, demonstrating a need for caution when interpreting ecotoxicity in a regulatory context. Environ Toxicol Chem 2019;38:2314-2325. © 2019 SETAC.


Asunto(s)
Organismos Acuáticos/efectos de los fármacos , Carbono/toxicidad , Ecotoxicología , Nanofibras/toxicidad , Animales , Línea Celular , Daphnia/efectos de los fármacos , Peces/crecimiento & desarrollo , Hemocitos/efectos de los fármacos , Mytilus/efectos de los fármacos , Nanofibras/ultraestructura , Especificidad de la Especie
9.
Environ Toxicol Chem ; 38(5): 925-935, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30698850

RESUMEN

Sorption of chemical substances to nanoparticles (NPs) in the aqueous phase strongly influences NP physicochemisty, and investigations of these complex interactions can provide important insights into the environmental fate of NPs. The objective of the present study was to use differences in copper (Cu) bioavailability to investigate aqueous-phase sorption with NPs that had different physicochemical characteristics (silicon [Si], perovskite, and titanium dioxide NPs [TiO2 NPs]). Sorption of Cu with NPs was assessed by the presence of adsorbent in water and onto the NP surface after ultracentrifugation, and by changes in Cu bioavailability under static conditions during exposure of larval zebrafish, as well as under conditions of continuous agitation during exposure of the alga Chlorella vulgaris. The presence of TiO2 NPs reduced total Cu in the water column and Cu bioavailability (measured by growth inhibition, mortality, and metallothionein 2 gene expression), confirming Cu sorption to TiO2 NPs. Nanoparticle surface area was the most important factor that affected Cu sorption, as indicated by less bioavailable Cu in the presence of smaller TiO2 NPs. The surface area effect was consistent regardless of exposure conditions (alga, continuous agitation; zebrafish, static water) and was further supported by the fact that the lowest total Cu concentration in the water column was found in the presence of the smallest NP. The results differed with other NP types, for example, silicon NPs, in which Cu sorption was indicated by analytical chemistry, but sorption was not sufficient to significantly alter Cu bioavailability. The bioavailability tests did not indicate Cu sorption with perovskite NPs. The results demonstrate that surface area critically influences sorption, that Cu sorption as measured by bioavailability is not affected by agitation or static conditions, and that Cu sorption differs among types of NPs, indicating differences in their surface physicochemistry. Environ Toxicol Chem 2019;9999:1-11. © 2019 SETAC.


Asunto(s)
Cobre/metabolismo , Nanopartículas/química , Agua/química , Adsorción , Animales , Disponibilidad Biológica , Compuestos de Calcio/química , Chlorella vulgaris/crecimiento & desarrollo , Regulación de la Expresión Génica , Larva/metabolismo , Metalotioneína/genética , Metalotioneína/metabolismo , Óxidos/química , Propiedades de Superficie , Titanio/química , Contaminantes Químicos del Agua/química , Pez Cebra/genética
10.
Chemosphere ; 218: 347-358, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30476766

RESUMEN

Graphene-related materials (GRMs) are one of the most attractive materials from an application perspective, consequently their release into aquatic environments is highly likely. In the present work, the potential of fish hepatocytes (topminnow fish hepatoma cell line, PLHC-1) and macrophages (carp leukocyte cell line, CLC) to study the toxicity and intracellular fate of helical-ribbon carbon nanofibers (CNFs) and graphene oxide (GO) used in a variety of intermediate industrial products was evaluated, allowing a first ranking of GRMs according to their cytotoxicity. Cells were exposed to a concentration range of 0-200 µg ml-1 of GRMs for 24 and 72 h and cell viability was assessed by measuring mitochondrial activity (AlamarBlue assay), plasma membrane integrity (5-carboxyfluorescein diacetate-acetoxymethyl ester assay) and lysosomal function (neutral red uptake assay). Results showed that both the cell type and the choice of endpoint determined the toxicity of GRMs. In both cell lines, CNFs appeared to have higher toxicity than GO and the highest degree of graphitization in fibers was associated with lower toxicity. Transmission electron microscopy revealed that CNFs were taken up into membrane-bound compartments of PLHC-1 cells in a size-independent manner, whereas in CLC, longer CNFs were encountered free in the cytoplasm and only the shorter CNFs were localized in membrane-surrounded vesicles. GO sheets were present within vesicles as well as free in the cytoplasm of both cell types. These findings contribute to the understanding of the toxicity and behaviour of these GRMs in living systems, therefore aiding in designing safer materials for the environment.


Asunto(s)
Ecotoxicología/métodos , Peces , Grafito/toxicidad , Nanofibras/toxicidad , Pruebas de Toxicidad/métodos , Animales , Línea Celular , Supervivencia Celular/efectos de los fármacos , Relación Dosis-Respuesta a Droga , Grafito/administración & dosificación , Grafito/química , Grafito/farmacocinética , Hepatocitos/efectos de los fármacos , Neoplasias Hepáticas Experimentales/patología , Lisosomas/efectos de los fármacos , Macrófagos/citología , Macrófagos/efectos de los fármacos , Microscopía Electrónica de Transmisión , Mitocondrias/efectos de los fármacos , Nanofibras/administración & dosificación , Nanofibras/química
11.
Ear Nose Throat J ; 97(4-5): E13-E17, 2018.
Artículo en Inglés | MEDLINE | ID: mdl-29940687

RESUMEN

Langerhans cell histiocytosis (LCH) is regarded as a clonal disease, usually carrying the activating BRAF mutation V600E. Although LCH theoretically may affect all types of human tissue and typically appears during childhood, temporal bone involvement in adult patients is exceedingly rare. We report an atypical case of a 56-year-old man as one of the oldest patients diagnosed with temporal bone involvement of a BRAF-negative LCH, which caused painless otorrhea and hearing loss. Cutaneous manifestation (multifocal multisystem LCH, also known as Letterer-Siwe disease) was later recognized incidentally. Administration of ifosfamide plus doxorubicin and mesna with supplementary irradiation resulted in a temporary remission followed by slow but constant tumor progression, which after 2.5 years became resistant to treatment with cytarabine and dasatinib. Attempts at therapy (cladribine) to achieve cure are ongoing.


Asunto(s)
Pérdida Auditiva/etiología , Histiocitosis de Células de Langerhans/complicaciones , Histiocitosis de Células de Langerhans/patología , Histiocitosis de Células de Langerhans/terapia , Humanos , Masculino , Persona de Mediana Edad , Hueso Temporal/patología
12.
Eur Arch Otorhinolaryngol ; 271(7): 2083-9, 2014 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-24609650

RESUMEN

Tuberculosis remains one of the most challenging infectious diseases, which rarely manifests in the middle ear cleft exclusively. Typical symptoms of tuberculosis have become more and more confusing due to the genetic evolution of different Mycobacterium species. In the diagnosis of tuberculous otitis media (TOM), clinical suspicion plays a fundamental role, when topical and/or systemic antibiotic treatment cannot lead to improvement in ear discharge and inflammation. If there is no other reason of persisting otorrhea, microbiological sampling and culturing are the subsequent steps of diagnosis. These investigations, however, have low sensitivity; therefore a canal wall-up mastoidectomy is recommended, which includes the removal of necrotic bone and multiple histological sampling from various locations. Currently, histopathological analysis is the most robust and reliable method in the diagnosis of TOM. Tuberculin skin test, Mycobacterium-specific PCR and interferon-gamma release assay cannot distinguish between active, inactive or post-infective conditions. According to these considerations, these methods may serve as supplementary assays for the final diagnosis. Having the appropriate diagnosis after surgical intervention and laboratory analysis, medical management should be continued by anti-tuberculosis chemotherapy. Hereby, we demonstrate two cases with primary TOM and provide an overview of the literature in the light of diagnostic and therapeutic guidelines in the management of TOM.


Asunto(s)
Antituberculosos/uso terapéutico , Otitis Media/microbiología , Otitis Media/patología , Tuberculosis/diagnóstico , Tuberculosis/tratamiento farmacológico , Adulto , Femenino , Humanos , Otitis Media/terapia , Adulto Joven
13.
Orv Hetil ; 153(46): 1832-8, 2012 Nov 18.
Artículo en Húngaro | MEDLINE | ID: mdl-23146783

RESUMEN

INTRODUCTION: Inflammatory bowel disease may show a life long persistence, while female fertility is time-limited. AIM: The aim of the authors was to obtain more knowledge about the obstetrical-gynecological aspects of this disorder. METHODS: The authors evaluated 100 patients with inflammatory bowel disease and 100 healthy women with a self-composed questionnaire. RESULTS: Menarche occurred significantly earlier in patients than in controls (p = 0,03). Either the activity of the disease, or the therapy itself may initiate irregularities in the menstrual cycle. Patients used contraceptives less frequently than controls (p = 0,002), and the time from family-planning to conception was longer in patients. Symptoms of bowel disease during pregnancy were not as severe as before and after pregnancy (p<0,001). Excess weight had a beneficial effect on symptoms during pregnancy (p = 0,042) and on the frequency of complications. Preterm birth and low birth weight were more frequent in newborns of patients (p = 0,019). CONCLUSION: Pregnancy has positive effect on the symptoms of inflammatory bowel disease in case gestation occurs in a stable period of the inflammatory bowel disease.


Asunto(s)
Recién Nacido de Bajo Peso , Enfermedades Inflamatorias del Intestino/complicaciones , Menarquia , Trastornos de la Menstruación/epidemiología , Trastornos de la Menstruación/etiología , Complicaciones del Embarazo/epidemiología , Complicaciones del Embarazo/etiología , Nacimiento Prematuro/epidemiología , Adulto , Edad de Inicio , Anciano , Lactancia Materna/estadística & datos numéricos , Estudios de Casos y Controles , Anticonceptivos/uso terapéutico , Femenino , Fertilización , Ginecología , Humanos , Hungría/epidemiología , Recién Nacido , Enfermedades Inflamatorias del Intestino/terapia , Persona de Mediana Edad , Obstetricia , Sobrepeso , Embarazo , Nacimiento Prematuro/etiología , Encuestas y Cuestionarios , Factores de Tiempo
14.
Arch Environ Contam Toxicol ; 62(1): 22-8, 2012 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-21468719

RESUMEN

A short-term whole-sediment test using the polychaete Arenicola marina was conducted under laboratory conditions to assess the bioavailability of metals bound to sediments collected from 12 sites of the Gulf of Cádiz. To achieve this objective, the rate of increase of metal bioaccumulation and the induction of a typical biomarker, metallothioneinlike proteins (MTLPs) were determined. Results of the multivariate analysis showed associated metal-rich sediments, increased rate of Cu and Zn accumulations, but lower toxicity with an increased MTLP induction, whereas sedimentary Ni and Co concentrations were related to higher toxicity to lugworms, although it might be caused by other contaminants present in these sediments. The linear kinetic approach was shown to be valid in certain circumstances, but more validation studies of this parameter are required before it can be recommended for use in evaluating metal bioavailability in sediments.


Asunto(s)
Monitoreo del Ambiente/métodos , Sedimentos Geológicos/química , Metales Pesados/farmacocinética , Poliquetos/metabolismo , Contaminantes Químicos del Agua/farmacocinética , Animales , Disponibilidad Biológica , Biomarcadores/metabolismo , Metaloproteínas/metabolismo , Metales Pesados/análisis , Metales Pesados/toxicidad , Análisis Multivariante , Poliquetos/efectos de los fármacos , España , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
15.
Environ Sci Pollut Res Int ; 17(9): 1519-28, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20496008

RESUMEN

BACKGROUND, AIM AND SCOPE: The influence of pH (range 6.5-8.5) on the uptake of Zn, Cd, Pb, Cu, Ni, Cr, Hg, and As by juveniles of the clam Ruditapes philippinarum was examined in order to understand whether variation in sediment pH has significant repercussions on metal bioaccumulation. MATERIALS AND METHODS: Clams were exposed to sediments collected in three locations in the Gulf of Cadiz (Huelva, Guadalquivir and Bay of Cadiz) and to contaminated particles derived from an accidental mining spill in Spain. RESULTS: With a notable exception of metal Cd, the concentration of metals within clams significantly increased (p < 0.1) when sediment pH was lowered by one or two units. Moreover, the magnitude of this effect was dependent on the type of sediment contamination. DISCUSSION: Lower pH increases metal solubility and reduces or invert the metal sorption of metals to sediments. Increases in free metal ions in water favors metal uptake by clams, hence pH is an important factor controlling the mobility of these metals within sediments and their subsequent bioaccumulation within biota. Although sediment-water exchange of Cd can increase with acidification, this excess may be counterbalanced by the presence of ligands in seawater preventing the uptake by organism. Besides chlorines, Cd has also an affinity with carbonates and other ligands present in sea water. These Cd-carbonate complexes may reduce the bioavailable to organisms. CONCLUSIONS: These results highlight the potential implications of sediment acidification, either due to the storage excess of organic matter or to the forced capture of CO(2), on the increasing metal availability to benthic organisms. RECOMMENDATIONS AND PERSPECTIVES: This kind of studies should be increased to address the influence of acidification in the behavior, bioavailability, toxicity, and risk assessment of contaminants associated with sediments either above sub-seabed geological formations in marine environments or in high enriched by organic matter in estuarine areas. Recently, the capture of CO(2) in marine environments has been approved and started; it is necessary to address the potential impacts associated with leakages or other events occurring during the procedure of injection and storage of CO2.


Asunto(s)
Bivalvos/metabolismo , Sedimentos Geológicos/química , Metales/metabolismo , Contaminantes Químicos del Agua/metabolismo , Ácidos/química , Ácidos/toxicidad , Animales , Bivalvos/efectos de los fármacos , Concentración de Iones de Hidrógeno , Metales/análisis , Metales/toxicidad , Contaminantes Químicos del Agua/análisis , Contaminantes Químicos del Agua/toxicidad
16.
Ecotoxicol Environ Saf ; 73(3): 306-11, 2010 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-19913912

RESUMEN

The induction of metallothionein-like proteins (MTLPs) as well as cadmium levels (Cd) was studied in tissues of gilthead sea bream Sparus aurata and flatfish Solea senegalensis after an intraperitoneal (i.p.) injection of cadmium (2.5 mg kg(-1) body weight). The liver, gills, intestine and blood of S. aurata as well as the liver and intestine of S. senegalensis were collected for analysis at 0, 3 and 6 days after the injection. Cd levels significantly increased in all tissues of the treated animals, and the highest accumulation was found in the liver in both species (p<0.05). Cadmium administration provoked significant inductions of MTLP synthesis in the liver and intestine of S. aurata (p<0.05), while no increase in these protein levels was recorded in tissues of S. senegalensis. Our findings imply that MTLP synthesis in S. aurata probably led to an enhanced ability to cope with the toxicant, whereas the MTLP induction in S. senegalensis was inhibited by the accumulated cadmium, as reflected by the mortality rate of this species. Under the experimental conditions, hepatic MTLPs appear to be a good indicator of the Cd level in S. aurata; however, no link was found between the cadmium concentration and MTLP induction in S. senegalensis, which suggests that MTLPs did not play a main role in detoxification by metal sequestration.


Asunto(s)
Cloruro de Cadmio/toxicidad , Peces Planos/fisiología , Contaminación de Alimentos/análisis , Dorada/fisiología , Contaminantes Químicos del Agua/toxicidad , Animales , Biomarcadores/metabolismo , Cloruro de Cadmio/farmacocinética , Branquias/efectos de los fármacos , Branquias/metabolismo , Inactivación Metabólica , Inyecciones Intraperitoneales , Mucosa Intestinal/metabolismo , Intestinos/efectos de los fármacos , Hígado/efectos de los fármacos , Hígado/metabolismo , Longevidad/efectos de los fármacos , Metalotioneína/biosíntesis , Metalotioneína/efectos de los fármacos , Pruebas de Toxicidad Aguda , Contaminantes Químicos del Agua/farmacocinética
17.
Mar Environ Res ; 66(1): 38-40, 2008 Jul.
Artículo en Inglés | MEDLINE | ID: mdl-18381224

RESUMEN

The coast of Huelva is considered as a heavily contaminated area where the Tinto and Odiel rivers discharge after running through a metalliferous mining area in the Iberian Pyrite Belt and end in common estuary called Ría of Huelva. Lead is a highly toxic and widely distributed element in the aquatic environment; therefore there is a great interest in assessing the impact of this contaminant on aquatic organisms. To study the bioavailability and sources of lead, the bivalve species Chamelea gallina was collected from six sampling sites along the coast of Huelva. Besides the effect of this metal on the enzyme activity, delta-aminolevulinic acid dehydratase (ALA-D) was determined in the whole tissue. Results show the inverse relationship between the lead concentration and the activity of ALA-D measured in whole tissues (r2=0.7). Individuals collected from the Ría of Huelva estuary had the highest levels of total lead concentrations and the lowest activity of ALA-D. Lead isotope analyses demonstrated the different sources of lead contamination and also confirmed the influence of Ría of Huelva on the metal input to the marine environment.


Asunto(s)
Bivalvos/enzimología , Exposición a Riesgos Ambientales/análisis , Monitoreo del Ambiente/métodos , Plomo/administración & dosificación , Plomo/farmacología , Porfobilinógeno Sintasa/metabolismo , Animales , Biomarcadores/análisis , Plomo/análisis , Océanos y Mares , España
18.
Environ Int ; 33(4): 445-55, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17196253

RESUMEN

The Tinto and Odiel rivers are seriously affected by acid mine drainage (AMD) from the long-term mining activities in Iberian Pyrite Belt (IPB). As a consequence, the Huelva estuary is heavily contaminated by metals and metalloids. This study presents an estimation of the seasonal variation, and the dissolved contaminant load transported by both rivers from February 2002 to September 2004. Besides, toxicity and bioaccumulation tests with the sediments of the estuary have been conducted in order to measure the mobility of the toxic metals. Results show that the Tinto and Odiel rivers transport enormous quantities of dissolved metals to the estuary: 7900 t yr(-1) of Iron (Fe), 5800 t yr(-1) Aluminium (Al), 3500 t yr(-1) Zinc (Zn), 1700 t yr(-1) Copper (Cu), 1600 t yr(-1) Manganese (Mn) and minor quantities of other metals and metalloids. These values represent 37% of the global gross flux of dissolved Zn transported by rivers in to the ocean, and 15% of the global gross flux of dissolved Cu. These metals and metalloids usually sink in the estuarine sediments due to pH and salinity changes. The increase of salinity in the estuary favours the adsorption and trapping of metals. For this reason, the mobility and bioavailability of metals such as Zn, Cd and Cu is higher in sediments located in the area of fresh water influence that in sediments located in the marine influenced area of the estuary, showing a higher percentage of fractionation and bioaccumulation of these metals in the station influenced by the fresh water environment.


Asunto(s)
Ácidos/análisis , Metales/análisis , Minería , Contaminantes Químicos del Agua/análisis , Animales , Disponibilidad Biológica , Sedimentos Geológicos , Metales/toxicidad , Ríos , España
19.
Environ Int ; 33(4): 463-8, 2007 May.
Artículo en Inglés | MEDLINE | ID: mdl-17218013

RESUMEN

Ecotoxicological effects associated with contaminants present in dredged material from Spain were determined using a marine biotest based on the determination of metallothionein-like-protein concentrations (MTLPs) in the shore crab Carcinus maenas. Intermoult female C. maenas were exposed in the laboratory to sediments from three Spanish ports, Ría de Huelva (SW, Spain), La Coruña (NW, Spain) and Bahía de Cádiz (SW, Spain) per replicate during 21 days. Hepatopancreas samples from crabs were taken for metallothioneins analysis on days 0, 7 and 21. Furthermore, chemical analysis was performed in the stations to determine the degree and nature of sediment contamination (Cr, Ni, Cu, Zn, Cd, Pb, Hg, As, PAHs and PCBs). A significant increase (p<0.05) in metallothionein concentration was observed over time in individuals exposed to sediment from the port Ría de Huelva characterized by high concentrations of metals. A toxicokinetic approach is proposed in this study related to the use of this biomarker in C. maenas to evaluate bioavailability associated with metals present in dredged material. As a first step, this toxicokinetic approach might reveal as a sensitive tool for evaluating bioavailability of contaminants present in dredged material.


Asunto(s)
Metalotioneína/metabolismo , Metales/análisis , Contaminantes Químicos del Agua/análisis , Animales , Disponibilidad Biológica , Crustáceos , Sedimentos Geológicos/química , Hepatopáncreas/química , Metales/farmacocinética , Metales/toxicidad , Contaminantes Químicos del Agua/farmacocinética , Contaminantes Químicos del Agua/toxicidad
20.
Chemosphere ; 66(3): 428-34, 2007 Jan.
Artículo en Inglés | MEDLINE | ID: mdl-16860849

RESUMEN

The harmful effects of contaminants on the ecosystems and humans are characterised by their environmental toxicity. The aim of this study was to assess applicability and reliability of several environmental toxicity tests, comparing the result of the whole soils and their water extracts. In the study real contaminated soils were applied from three different inherited contaminated sites of organic and inorganic pollutants. The measured endpoints were the bioluminescence inhibition of Vibrio fischeri (bacterium), the dehydrogenase activity inhibition of Azomonas agilis (bacterium), the reproduction inhibition of Tetrahymena pyriformis (protozoon), and Panagrellus redivivus (nematode), the mortality of Folsomia candida (springtail), the root and shoot elongation inhibition of Sinapis alba (plant: white mustard) and the nitrification activity inhibition of an uncontaminated garden soil used as "test organism". Besides the standardised or widely used methods some new, direct contact ecotoxicity tests have been developed and introduced, which are useful for characterisation of the risk of contaminated soils due to their interactive nature. Soil no. 1 derived from a site polluted with transformer oil (PCB-free); Soil no. 2 originated from a site contaminated with mazout; Soil no. 3 was contaminated with toxic metals (Zn, Cd, Cu, Pb, As). In most cases, the interactive ecotoxicity tests indicated more harmful effect of the contaminated soil than the tests using soil extracts. The direct contact environmental toxicity tests are able to meet the requirements of environmental toxicology: reliability, sensibility, reproducibility, rapidity and low cost.


Asunto(s)
Contaminantes del Suelo/toxicidad , Suelo/análisis , Pruebas de Toxicidad/métodos , Aliivibrio fischeri/efectos de los fármacos , Aliivibrio fischeri/metabolismo , Animales , Artrópodos/efectos de los fármacos , Artrópodos/crecimiento & desarrollo , Monitoreo del Ambiente/métodos , Luminiscencia , Nematodos/efectos de los fármacos , Nematodos/crecimiento & desarrollo , Oxidorreductasas/antagonistas & inhibidores , Oxidorreductasas/metabolismo , Pseudomonadaceae/efectos de los fármacos , Pseudomonadaceae/enzimología , Sinapis/efectos de los fármacos , Sinapis/crecimiento & desarrollo , Tetrahymena pyriformis/efectos de los fármacos , Tetrahymena pyriformis/crecimiento & desarrollo
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