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1.
J Eur Acad Dermatol Venereol ; 33(10): 1928-1934, 2019 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-31055872

RESUMO

BACKGROUND: Nickel (Ni) dermatitis remains a highly prevalent allergic condition in Italy. There is a continuous need for clinical and epidemiological surveillance to evaluate whether or not European Ni Directive has been effective in contact allergy prevention. OBJECTIVES: To assess the prevalence of Ni dermatitis among patch-tested patients and self-interviewed school students and to analyse Ni release from earlobe jewellery. METHODS: Results of patch tests performed in 2006-2007, 2015-2016 and 2017-2018 were retrieved. A questionnaire was compiled by 315 secondary school students. Ni release from earring parts was analysed with the EN1811:2015 method. RESULTS: A significant time trend of decreasing Ni positivity from 2006-2007 to 2017-2018 was observed both in the overall population (44.1% in 2006-2007, 33.0% in 2015-2016, 31.6% in 2017-2018, P < 0.0001) and in female patients (P < 0.0001). Conversely, change was not significant in males (P = 0.16). Decrease was significant for all age groups, except for those aged >60 years (P = 0.51). Among 242 students who reported earring use, 130 (54%) reported symptoms at earlobes, mostly associated with jewellery of materials other than gold and silver (59% of those with earlobe symptoms). Ni release exceeded the migration limit in 4/21 (20%) earring parts. CONCLUSIONS: A high prevalence of Ni dermatitis and earlobe symptoms were found in Rome. A decreasing time trend was noted, with a significant decline in Ni sensitivity compared to the situation observed right after Ni Directive implementation. This most likely represents the consequence of reduced Ni content in earring parts, although a major care in the use of Ni-containing objects could contribute to explain these findings.


Assuntos
Dermatite Alérgica de Contato/epidemiologia , Dermatite Alérgica de Contato/etiologia , Joias/efeitos adversos , Níquel/efeitos adversos , Adolescente , Adulto , Dermatite Alérgica de Contato/prevenção & controle , Pavilhão Auricular , União Europeia , Feminino , Humanos , Joias/análise , Legislação como Assunto , Masculino , Pessoa de Meia-Idade , Níquel/análise , Testes do Emplastro , Prevalência , Cidade de Roma/epidemiologia , Fatores Sexuais , Inquéritos e Questionários , Adulto Jovem
2.
Food Chem Toxicol ; 156: 112447, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-34343597

RESUMO

Recently, the cultivation of light Cannabis, with a total THC content less than 0.6%, has been encouraged due to its industrial and therapeutic potential. This has increased the consumption of hemp for both smoking purposes and food preparation. Even so, Cannabis inflorescences are not subject to EU regulations and standards provided for food and tobacco products. A study was carried out on thirty-one inflorescences samples, collected in different Italian regions, in order to determine cannabinoids, pesticides and metals and to evaluate the exposure of consumers to contaminants and ensure a safe consumption. Contents of THC were always below 0.5%, while CBD ranged between 0.3 and 8.64%. The determination of 154 pesticides showed that 87% of the samples contained fungicides and insecticides in the range 0.01-185 µg/g. The most found are spinosad and cyprodinil. The concentration of metals ranged from 1 to more than 100 µg/g and As, Cd, Co, Cr, Hg, Cu, Mo, Ni and V exceeded the regulatory US limits for inhaled Cannabis products, while Pb exceeded them for both oral and inhaled products. These contaminants are intrinsically toxic and may affect public health. Actions are needed to establish regulatory measures and reduce the adverse effects caused by contaminants in Cannabis.


Assuntos
Canabinoides/toxicidade , Cannabis/química , Inflorescência/química , Metais/toxicidade , Praguicidas/toxicidade , Canabinoides/análise , Itália , Metais/análise , Praguicidas/análise
3.
Food Chem Toxicol ; 146: 111816, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33080330

RESUMO

The recent application of manufactured nanomaterials (MNMs) in plant protection products (PPPs) enhances stability of the active substance (a.s.), minimizes application losses, reduces the quantities of a.s., increases coverage on leaf surface, improves precise application, etc. Besides offering benefits, there is high concern about the potential risk for human and environment associated with the use of nanopesticides. In this study, a panel of complementary methodologies were used to determine size distribution and chemical identification of four different formulations of nanopesticides. Measurements were performed by dynamic light scattering (DLS), transmission electron microscopy (TEM), asymmetric field flow fractionation-multi angle light scattering (AF4-FFF-MALS), gas/liquid chromatography with mass spectrometry (GC-MS/MS, LC-MS/MS) or diode array detector (HPLC-DAD) and inductively coupled plasma mass spectrometry (ICP-MS). Results indicated average size values in the ranges: 27.4-148.7 nm by DLS; 39.1-82.0 nm by AF4-FFF-MALS; and 42-90 nm by TEM. Linked to these nanosized particles both organic active ingredients and inorganic ones were identified. In addition, the obtained data revealed that all the four PPPs contained more than 50% of particles with number size distribution between 1 and 100 nm and, according to the European Commission definition, they can be defined as nanopesticides.


Assuntos
Nanotecnologia , Praguicidas/química , Cromatografia Líquida de Alta Pressão/métodos , Fracionamento por Campo e Fluxo , Hidrodinâmica , Espectrometria de Massas/métodos , Microscopia Eletrônica de Transmissão , Praguicidas/análise
4.
J Toxicol Environ Health A ; 72(2): 88-93, 2009.
Artigo em Inglês | MEDLINE | ID: mdl-19034798

RESUMO

The Pd tissue distribution and elimination in rats following oral exposure in drinking water of dipotassium hexachloropalladate at doses of 100 or 250 ng/ml for 14 d were determined. The sector field inductively coupled plasma mass spectrometry used for Pd quantification showed the adequate sensitivity (10 ng/l) and accuracy (96-105%), and all the more in consideration of the very low levels of Pd accumulated. Tissues were taken and analyzed after 14 d. The tissue containing the highest Pd concentration was the kidney (4 ng/g dry weight in controls and 75 ng/g dry weight at the maximum dose), with left and right kidneys showing a comparable accumulation. The Pd kidney levels rose, but not significantly, with the administered dose. None of the other organs (liver, lung, spleen, adrenal glands, and bones) appeared to accumulate Pd, even at the highest dose. At the 250-ng/ml dose, small amounts of Pd were found in serum (0.27 ng/ml vs. 0.19 ng/ml in controls), while they were higher in urine (1.2 ng/ml vs. 0.16 ng/ml in controls) and in feces (3,231 ng/g dry weight vs. 69 ng/g dry weight in controls). Feces were the main excretion route for Pd, with a significant linear correlation with exposed dose, which is likely due to low intestinal absorption of Pd.


Assuntos
Paládio/farmacocinética , Abastecimento de Água , Administração Oral , Animais , Masculino , Espectrometria de Massas , Distribuição Aleatória , Ratos , Ratos Wistar , Estatísticas não Paramétricas , Distribuição Tecidual
5.
Neurotoxicology ; 29(1): 60-72, 2008 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-17936361

RESUMO

We have studied at the ultrastructural level the presence of manganese (Mn) in rat basal ganglia, which are target regions of the brain for Mn toxicity. The rats underwent a moderate level of Mn exposure induced per os for 13 weeks. Mn was detected by means of electron spectroscopy imaging (ESI) and electron energy-loss spectroscopy (EELS) analyses on perfusion fixed samples embedded in resin. While no significant contamination by exogenous Mn occurred during the processing procedures, less than 50% of endogenous Mn was lost during fixation and dehydration of the brain samples. The residual Mn ions in the samples appeared as discrete particles, localized in selected sub-cellular organelles in a cell, suggesting that no significant translocation had occurred in the surrounding area. In control rats, the Mn sub-cellular localization and relative content were the same in neurons and astrocytes of rat striatum and globus pallidus: the Mn level was highest in the heterochromatin and in the nucleolus, intermediate in the cytoplasm, and lowest in the mitochondria (p<0.001). After chronic Mn treatment, while no ultrastructural damage was detected in the neurons and glial cells, the largest rate of Mn increase was noted in the mitochondria of astrocytes (+700%), an intermediate rate in the mitochondria of neurons (+200%), and the lowest rate in the nuclei (+100%) of neurons and astrocytes; the Mn level in the cytoplasm appeared unchanged. EELS analysis detected the specific spectra of Mn L(2,3) (peak at DeltaE = 665 eV) in such organelles, confirming the findings of ESI. Although a consistent loss of Mn occurred during the processing of tissue samples, ESI and EELS can be useful methods for localization of endogenous Mn in embedded tissues. The high rate of Mn sequestration in the mitochondria of astrocytes in vivo may partly explain the outstanding capacity of astrocytes to accumulate Mn, and their early dysfunction in Mn neurotoxicity. The high level of Mn in the heterochromatin and nucleoli of neurons and astrocytes in basal conditions and its further increase after Mn overload should provide insight into new avenues of investigating the role of Mn in the normal brain and a baseline for future Mn toxicity studies.


Assuntos
Gânglios da Base/efeitos dos fármacos , Manganês/metabolismo , Manganês/toxicidade , Oligoelementos/metabolismo , Oligoelementos/toxicidade , Análise de Variância , Animais , Gânglios da Base/metabolismo , Gânglios da Base/ultraestrutura , Citoplasma/efeitos dos fármacos , Citoplasma/ultraestrutura , Masculino , Microscopia Eletrônica de Transmissão/métodos , Mitocôndrias/efeitos dos fármacos , Mitocôndrias/ultraestrutura , Neurônios/efeitos dos fármacos , Neurônios/ultraestrutura , Ratos , Ratos Wistar , Espectroscopia de Perda de Energia de Elétrons/métodos , Frações Subcelulares/efeitos dos fármacos , Frações Subcelulares/metabolismo
6.
Toxicol Lett ; 298: 25-32, 2018 Dec 01.
Artigo em Inglês | MEDLINE | ID: mdl-29953930

RESUMO

Although high or repeated exposure to different forms of Hg can have serious health consequences, the most important toxicity risk for humans is as methylmercury (MeHg) which exposure is mainly through consumption of fish. Generally, more than the 80% of Hg in hair is as MeHg, which is taken up by hair follicles as MeHg-cysteine complexes. In this context, hair samples were collected from 200 children (7 years) living in a coastal site in the North-East (A) of Italy and from 299 children (6-11 years) living in a urban area of South of Italy (B) to determine the levels of MeHg. Considering the neurotoxicity of MeHg, children were subjected to cognitive and neuropsychological tests. The hair values of Hg in the children population groups were comparable with data reported in other international surveys. On the other hand, combining results of the neurological tests with Hg levels, a possible relationship between Hg and an increase of the errors average reported in some neurological tests has been noted. Although the Hg levels were not elevated, a possible neurological influence in children, a population more susceptible than adults, might not be excluded, but the influence on neurological performances of the children could be also due to the family environment (socio economic status, educational level, etc.).


Assuntos
Poluentes Ambientais/análise , Cabelo/química , Compostos de Metilmercúrio/análise , Fatores Etários , Criança , Comportamento Infantil , Desenvolvimento Infantil , Cognição , Monitoramento Ambiental/métodos , Poluentes Ambientais/efeitos adversos , Feminino , Contaminação de Alimentos , Humanos , Masculino , Intoxicação do Sistema Nervoso por Mercúrio/diagnóstico , Intoxicação do Sistema Nervoso por Mercúrio/etiologia , Intoxicação do Sistema Nervoso por Mercúrio/fisiopatologia , Intoxicação do Sistema Nervoso por Mercúrio/psicologia , Compostos de Metilmercúrio/efeitos adversos , Testes Neuropsicológicos , Características de Residência , Medição de Risco , Alimentos Marinhos/efeitos adversos
7.
J Pharm Biomed Anal ; 44(5): 1197-202, 2007 Sep 03.
Artigo em Inglês | MEDLINE | ID: mdl-17566689

RESUMO

It is extensively well-known that Ni and other metals occurring as impurities in cosmetic products might give rise to contact dermatitis in subjects with pre-existing allergy. The present study on the content of 13 metals (Cd, Co, Cr, Cu, Hg, Ir, Mn, Ni, Pb, Pd, Pt, Rh, and V) in moisturizing creams, labelled as "Ni-tested" (i.e., Ni content <100 ng g(-1)) and available on the Italian market, provides a basis for assessing their safety for consumers. Quantification of metals was performed by sector field inductively coupled plasma mass spectrometry after microwave-assisted acid digestion of products. The developed method had limits of quantification less than 0.8 ng g(-1) for all the elements; recovery was in the interval 88% (Cd, Co) to 110% (Hg), and precision was always under 7%. Nickel was present in all the products with levels between 17.5 and 153 ng g(-1); three skin creams were slightly above the concentration reported on the label. The other elements were at levels below 1 microg g(-1). The highest concentrations, in ng g(-1), of Co, Cr, Cu, and Mn were 222, 303, 51.2, and 59.9, respectively. Mean Cd, Pb, and V were below 5 ng g(-1), while Hg was absent in all the samples. Among the new emergent allergens, Ir and Rh were in traces or even undetectable, while Pt had levels of 2.65 and 6.28 ng g(-1) in two creams and Pd was equal to 1.07 ng g(-1) in one product. The overall results are below the sensitizing limit proposed for consumer products and, thus, probably have no significant toxicological effects. Nevertheless, some creams presented amounts of Co and Cr comparable to those of Ni and therefore they have to be monitored in consideration of their cross-reactivity as well.


Assuntos
Alérgenos/análise , Fármacos Dermatológicos/análise , Metais Pesados/análise , Níquel/análise , Higiene da Pele/métodos , Ácidos , Aconitato Hidratase , Alérgenos/efeitos adversos , Dermatite Alérgica de Contato/etiologia , Emolientes/efeitos adversos , Emolientes/análise , Humanos , Espectrometria de Massas/métodos , Metais Pesados/efeitos adversos , Micro-Ondas , Níquel/efeitos adversos , Pomadas/efeitos adversos , Pomadas/análise
8.
Sci Total Environ ; 388(1-3): 24-34, 2007 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-17884145

RESUMO

The capability of alloys used in cheap jewellery to release metal ions on contact with the skin causing allergic contact dermatitis (ACD) is generally acknowledged. To reduce the diffusion of the Ni-induced ACD the Council Directive 94/27/EC [Council Directive 94/27/EC of 30 June 1994. Official Journal L 188, 22/07/1994, 1.] limited the total Ni content in alloys and its release rate in artificial sweat. In this work, three different aspects were explored: i) the frequency of skin sensitization to Ni-containing earrings in patients before and after the introduction of the Directive's limit; ii) metal composition of alloys by X-ray analysis; iii) metal leaching in artificial sweat followed by Sector Field Inductively Coupled Plasma Mass Spectrometry (SF-ICP-MS) quantification. Well-known allergenic metals, as Ni, Cr and Co, and possible emergent allergens, as Al, Ag, Au, Cd, Cu, Fe, Ir, Mn, Pb, Pd, Pt, Rh, Sn, V and Zn, were studied. Results showed that the frequency of allergy due to earrings did not decrease after the introduction of the Ni limit: in 1994 and in 2005 patients positive to Ni patch tests were 54.3% and 53.5%, respectively. The earring components analyzed were Fe-based or alloys of Cu/Zn or Fe/Cr/Ni, plated with a thin film of precious metal (Ag, Au) which, in several cases, was combined with a Ni layer beneath. Five out of 10 items were not in compliance with the Ni Directive 94/27/EC having a total Ni content >0.05%. In three cases the release of Ni concentrations was higher than the safe sensitizing limit given by the above mentioned Regulation (i.e., <0.5 microg/cm(2)/week). The release of Cu and Zn was very variable among the different pieces (Cu: 0.134-30.9 microg/cm(2)/week; Zn: 0.141-160 microg/cm(2)/week); two objects released high amounts of Fe (358 and 586 microg/cm(2)/week) and one released considerable Mn (21 microg/cm(2)/week). Lead was released from 70% of the objects, while Ag, Al, Cd, Co, Cr and Sn from ca. 30% of the items and concentrations of these elements were well below 0.5 microg/cm(2)/week. Vanadium was released by only one item whereas Au, Ir, Pd, Pt and Rh were never leached.


Assuntos
Qualidade de Produtos para o Consumidor , Dermatite Alérgica de Contato/etiologia , Metais/efeitos adversos , Metais/análise , Dermatite Alérgica de Contato/epidemiologia , Monitoramento Ambiental , Monitoramento Epidemiológico , Humanos , Itália/epidemiologia , Projetos Piloto , Testes Cutâneos
9.
J Neurol Sci ; 248(1-2): 23-30, 2006 Oct 25.
Artigo em Inglês | MEDLINE | ID: mdl-16765382

RESUMO

BACKGROUND: Involvement of metals in the risk of developing Parkinson's disease (PD) has been suggested. In the present study, concentration of metals in cerebrospinal fluid (CSF), blood, serum, urine and hair of 91 PD patients and 18 controls were compared. METHODS: Blood and hair were microwave digested, while CSF, serum and urine were water-diluted. Elements quantification was achieved by Inductively Coupled Plasma Atomic Emission Spectrometry and Sector Field Inductively Coupled Plasma Mass Spectrometry. RESULTS: Some metal imbalances in PD were observed: i), in CSF, lower Fe and Si; ii), in blood, higher Ca, Cu, Fe, Mg and Zn; iii), in serum, lower Al and Cu; iv), in urine, lower Al and Mn, higher Ca and Fe; and v), in hair, lower Fe. The ROC analysis suggested that blood Ca, Fe, Mg and Zn were the best discriminators between PD and controls. In addition, hair Ca and Mg were at least 1.5 times higher in females than in males of patients and controls. A decrement with age of patients in hair and urine Ca and, with less extent, in urine Si was observed. Magnesium concentration in CSF decreased with the duration and severity of the disease. Elements were not influenced by the type of antiparkinsonian therapy. CONCLUSIONS: Variation in elements with the disease do not exclude their involvement in the neurodegeneration of PD.


Assuntos
Metais/sangue , Metais/líquido cefalorraquidiano , Transtornos Parkinsonianos/sangue , Transtornos Parkinsonianos/induzido quimicamente , Fatores Etários , Idoso , Idoso de 80 Anos ou mais , Feminino , Cabelo/metabolismo , Humanos , Masculino , Metais/urina , Pessoa de Meia-Idade , Transtornos Parkinsonianos/urina , Curva ROC , Espectrofotometria Atômica/métodos , Estatísticas não Paramétricas
10.
G Ital Med Lav Ergon ; 28(2): 202-3, 2006.
Artigo em Italiano | MEDLINE | ID: mdl-16805466

RESUMO

Iridium (Ir) is one of the six elements collectively known as the platinum group metals. For its excellent catalytic properties, Ir was recently introduced into DeNOx, a new generation of automotive catalysts. The aim of our study was to evaluate urinary Ir levels in an urban population. A total of 122 healthy male subjects of Rome (Italy) were studied. Ir quantification in the urine samples of these subjects was carried out by sector field inductively coupled plasma mass spectrometry. The mean urinary Ir level was 10.41 ng/g creatinine (standard deviation: 9.67; 25th-75th percentile: 3,62-12,74 ng/g creatinine). The scientific community should respond to a potential increase in environmental exposure to Ir, due to its growing use as a catalyst, with very careful evaluation of the biological levels of this metal and monitoring of airborne particulate present in the life environment. Further investigation will enable researchers to confirm and integrate the findings of our present study undertaken in the context of surveillance.


Assuntos
Monitoramento Ambiental , Irídio/urina , Adulto , Humanos , Itália , Masculino , Pessoa de Meia-Idade , População Urbana
11.
Artigo em Inglês | MEDLINE | ID: mdl-12450533

RESUMO

Zilpaterol is an adrenergic drug currently licensed in Mexico and South Africa as a feed additive for cattle close to consignment. In this study an analytical method to detect zilpaterol in commercial feeds was set up. The influence of extraction solvent and matrix was evaluated. The drug as a trimethylsilyl derivative was characterized by GC-MS, on a quadrupole detector, in the electron impact mode. Acidic extraction, solid-phase extraction C(18) non-endcapped clean-up and mass characterization on ions m/z 308, 291, 405, 390 provided zilpaterol recoveries >75.3% and repeatability <3.3% in feeds spiked in the range 30.0-120.0 ng/g. The limits of detection and quantification were 7.5 and 25.0 ng/g, respectively. Such limits are well below the dose of 5.0-20.0 microgram/g proposed as effective.


Assuntos
Ração Animal/análise , Cromatografia Gasosa-Espectrometria de Massas/métodos , Compostos de Trimetilsilil/análise , Animais , Bovinos , Cromatografia Líquida de Alta Pressão , Reprodutibilidade dos Testes , Sensibilidade e Especificidade
12.
Occup Environ Med ; 61(7): 636-9, 2004 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-15208381

RESUMO

BACKGROUND: Over the past two decades there has been a substantial increase in environmental levels of palladium, platinum, and rhodium, the platinum group elements (PGEs), due to the widespread use of catalytic converters for automotive traction. AIM: To evaluate urinary platinum levels in occupationally exposed subjects. METHODS: A total of 161 employees from the Rome City Police Force were studied; 103 were traffic police involved in controlling streets with an average flow of vehicles, while the remaining 58 were control subjects engaged only in office work. Platinum quantification in the urine samples of these subjects was carried out by sector field inductively coupled plasma mass spectrometry. RESULTS: There were no statistically significant differences between platinum levels in the group of subjects engaged in traffic control and the control group (4.45 (2.42) ng/l v 4.56 (2.84) ng/l, respectively). CONCLUSIONS: Urinary levels were found to be higher than those reported for other urban populations, thus showing a progressive increase in human exposure to Pt.


Assuntos
Poluentes Ocupacionais do Ar/toxicidade , Platina/urina , Polícia , Adulto , Distribuição por Idade , Monitoramento Ambiental/métodos , Monitoramento Epidemiológico , Feminino , Humanos , Exposição por Inalação/efeitos adversos , Masculino , Pessoa de Meia-Idade , Exposição Ocupacional , Platina/efeitos adversos , Cidade de Roma/epidemiologia , População Urbana , Emissões de Veículos
13.
Sci Total Environ ; 299(1-3): 1-19, 2002 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-12462571

RESUMO

Traffic is the main source of platinum-group element (PGE) contamination in populated urban areas. There is increasing concern about the hazardous effects of these new pollutants for people and for other living organisms in these areas. Airborne and road dusts, as well as tree bark and grass samples were collected at locations in the European cities of Göteborg (Sweden), Madrid (Spain), Rome (Italy), Munich (Germany), Sheffield and London (UK). Today, in spite of the large number of parameters that can influence the airborne PGE content, the results obtained so far indicate significantly higher PGE levels at traffic sites compared with the rural or non-polluted zones that have been investigated (background levels). The average Pt content in airborne particles found in downtown Madrid, Göteborg and Rome is in the range 7.3-13.1 pg m(-3). The ring roads of these cities have values in the range 4.1-17.7 pg m(-3). In Munich, a lower Pt content was found in airborne particles (4.1 pg m(-3)). The same tendency has been noted for downtown Rh, with contents in the range 2.2-2.8 pg m(-3), and in the range 0.8-3.0 and 0.3 pg m(-3) for motorway margins in Munich. The combined results obtained using a wide-range airborne classifier (WRAC) collector and a PM-10 or virtual impactor show that Pt is associated with particles for a wide range of diameters. The smaller the particle size, the lower the Pt concentration. However, in particles

Assuntos
Poluentes Atmosféricos/análise , Exposição por Inalação , Compostos de Platina/análise , Saúde Pública , Emissões de Veículos/análise , Poluentes Atmosféricos/efeitos adversos , Cidades , Poeira , Monitoramento Ambiental , Europa (Continente) , Humanos , Tamanho da Partícula , Compostos de Platina/efeitos adversos , Medição de Risco , População Urbana , Emissões de Veículos/efeitos adversos
14.
Sci Total Environ ; 296(1-3): 199-208, 2002 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-12398337

RESUMO

A comparison of platinum-group element (PGE) emission between gasoline and diesel engine catalytic converters is reported within this work. Whole raw exhaust fumes from four catalysts of three different types were examined during their useful lifetime, from fresh to 80,000 km. Two were gasoline engine catalysts (Pt-Pd-Rh and Pd-Rh), while the other two were diesel engine catalysts (Pt). Samples were collected following the 91441 EUDC driving cycle for light-duty vehicle testing, and the sample collection device used allowed differentiation between the particulate and soluble fractions, the latter being the most relevant from an environmental point of view. Analyses were performed by inductively coupled plasma-mass spectrometry (ICP-MS) (quadrupole and high resolution), and special attention was paid to the control of spectral interference, especially in the case of Pd and Rh. The results obtained show that, for fresh catalysts, the release of particulate PGE through car exhaust fumes does not follow any particular trend, with a wide range (one-two orders of magnitude) for the content of noble metals emitted. The samples collected from 30,000-80,000 km present a more homogeneous PGE release for all catalysts studied. A decrease of approximately one order of magnitude is observed with respect to the release from fresh catalysts, except in the case of the diesel engine catalyst, for which PGE emission continued to be higher than in the case of gasoline engines. The fraction of soluble PGE was found to represent less than 10% of the total amount released from fresh catalysts. For aged catalysts, the figures are significantly higher, especially for Pd and Rh. Particulate PGE can be considered as virtually biologically inert, while soluble PGE forms can represent an environmental risk due to their bioavailability, which leads them to accumulate in the environment.


Assuntos
Poluentes Atmosféricos/análise , Gasolina/análise , Paládio/análise , Platina/análise , Ródio/análise , Emissões de Veículos/análise , Espectrometria de Massas , Medição de Risco , Solubilidade
15.
Sci Total Environ ; 257(1): 1-15, 2000 Jul 20.
Artigo em Inglês | MEDLINE | ID: mdl-10943898

RESUMO

Automotive catalytic converters, in which Pt, Pd and Rh (platinum-group elements; PGEs) are the active components for eliminating several noxious components from exhaust fumes, have become the main source of environmental urban pollution by PGEs. This work reports on the catalyst morphology through changes in catalyst surface by scanning electron microscopy/energy dispersive X-ray spectroscopy (SEM/EDX) and laser-induced breakdown spectrometry (LIBS) from fresh to aged catalytic converters. The distribution of these elements in the fresh catalysts analysed (Pt-Pd-Rh gasoline catalyst) is not uniform and occurs mainly in a longitudinal direction. This heterogeneity seems to be greater for Pt and Pd. PGEs released by the catalysts, fresh and aged 30,000 km, were studied in parallel. Whole raw exhaust fumes from four catalysts of three different types were also examined. Two of these were gasoline catalysts (Pt-Pd Rh and Pd-Rh) and the other two were diesel catalysts (Pt). Samples were collected following the 91,441 EUDC driving cycle for light-duty vehicle testing. The results show that at 0 km the samples collected first have the highest content of particulate PGEs and although the general tendency is for the release to decrease with increasing number of samples taken, exceptions are frequent. At 30,000 km the released PGEs in gasoline and diesel catalysts decreased significantly. For fresh gasoline catalysts the mean of the total amount released was approximately 100, 250 and 50 ng km(-1) for Pt, Pd and Rh, respectively. In diesel catalysts the Pt release varied in the range 400-800 ng km-1. After ageing the catalysts up to 30,000 km, the gasoline catalysts released amounts of Pt between 6 and 8 ng km(-1), Pd between 12 and 16 ng km(-1) and Rh between 3 and 12 ng km(-1). In diesel catalysts the Pt release varied in the range 108-150 ng km(-1). The soluble portion of PGEs in the HNO3 collector solution represented less than 5% of the total amount for fresh catalysts. For 30,000 km the total amount of soluble PGEs released was similar or slightly higher than for 0 km.


Assuntos
Paládio/análise , Platina/análise , Rubídio/análise , Emissões de Veículos , Eletroquímica/métodos , Monitoramento Ambiental/métodos , Lasers , Microscopia Eletrônica de Varredura/métodos , Controle de Qualidade , Espectrometria de Massa de Íon Secundário/métodos , Análise Espectral/métodos , Propriedades de Superfície
16.
Exp Gerontol ; 60: 197-206, 2014 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-25446984

RESUMO

The concentration of calcium (Ca), cobalt (Co), copper (Cu), iron (Fe), magnesium (Mg), manganese (Mn) and selenium (Se) in plasma of 76 nonagenarians (mean age, 89.0±6.3 years), 64 centenarians (mean age, 101±1 years) and 24 middle-aged subjects as controls (mean age 61.2±1.1 years), was determined by sector field inductively coupled plasma mass spectrometry. All the subjects lived in Sardinia, an Italian island, that has the higher prevalence of centenarians than in other European countries. A comparison among the three classes of age showed a significant depletion of Ca, Co, Fe, Mn and Se (all p<0.001) in nonagenarians and centenarians with respect to controls. In particular, the geometric mean (GM) values of Ca, Co, Fe, Mn and Se were: 94.1 µg/ml, 0.46 ng/ml, 1314 ng/ml, 2.47 ng/ml and 111 ng/ml in controls; 87.6 µg/ml, 0.22 ng/ml, 815 ng/ml, 1.07 ng/ml and 88.9 ng/ml in nonagenarians; 87.0 µg/ml, 0.29 ng/ml, 713 ng/ml, 1.27 ng/ml and 81.9 ng/ml in centenarians. The highest inverse relationship with age was observed for Fe (p<0.001; ρ=-0.352) and Se (p<0.001; ρ=-0.417). This trend was also observed when data were sorted by gender. On the other hand, Cu and Mg levels in plasma remained substantially unchanged during aging. As regards Cu, it was significantly higher in females than in males in controls (GM, 1294 ng/ml vs. 1077 ng/ml; p=0.012), in nonagenarians (GM, 1216 ng/ml vs. 1081 ng/ml; p=0.011) as well as in centenarians (GM, 1226 ng/ml vs. 1152 ng/ml; p=0.045) and in hypertensive subjects with respect to healthy people (GM, 1215 ng/ml vs. 1129 ng/ml; p=0.021). These data can be used to enhance knowledge and support the research on: i) metals involved in aging in areas with high rates of human longevity; ii) variables (gender, lifestyle habits and health status) as critical determinants in aging; and iii) mineral intake and supplementation at older age affecting the healthy aging.


Assuntos
Envelhecimento/sangue , Longevidade/fisiologia , Metais/sangue , Idoso de 80 Anos ou mais , Cálcio/sangue , Estudos de Casos e Controles , Cobalto/sangue , Cobre/sangue , Feminino , Humanos , Ferro/sangue , Itália , Magnésio/sangue , Masculino , Manganês/sangue , Pessoa de Meia-Idade , Selênio/sangue
17.
Neurology ; 76(6): 549-55, 2011 Feb 08.
Artigo em Inglês | MEDLINE | ID: mdl-21300970

RESUMO

BACKGROUND: Metals are suspected of being involved in the pathogenesis of various neurologic diseases. We previously found a complex imbalance in serum chemical elements and oxidative status in patients with clinically definite multiple sclerosis (CDMS). OBJECTIVE: To understand whether this imbalance affects people with clinically isolated syndrome (CIS) and, if so, whether it predicts conversion to CDMS. METHODS: We studied 22 chemical elements and the oxidative status in 49 patients with CIS, 49 patients with CDMS, and 49 healthy donors (HD). Univariate and multivariate approaches were used to identify profiles for each group. A logistic regression analysis was used to identify the predictive potential of baseline data (elements, oxidative status, and MRI findings) for conversion to CDMS over 36 months. RESULTS: Several elements and oxidative status values differed significantly among the 3 groups. Discriminant analysis revealed a major contribution of Ca, Fe, Sn, Zn, serum antioxidant capacity, and serum oxidative status, which resulted in distinct profiles (the prediction of group membership was 96% [cross-validated 92%] for HD, 92% [cross-validated 92%] for CDMS, and 90% [cross-validated 86%] for CIS). A weighted combination of element concentrations and oxidative status values, adjusting for all other predictors, would predict a reduction in the risk of conversion to CDMS within 3 years (odds ratio 0.37; 95% confidence interval 0.18-0.76; p = 0.007), thereby proving more effective than MRI at baseline. CONCLUSIONS: The peculiar imbalance in serum elements and oxidative status that characterizes patients with CIS and may predict conversion to CDMS warrants studies on larger sample sizes.


Assuntos
Doenças Desmielinizantes/sangue , Doenças Desmielinizantes/diagnóstico , Estresse Oxidativo/fisiologia , Oligoelementos/sangue , Adolescente , Adulto , Biomarcadores/sangue , Doenças Desmielinizantes/epidemiologia , Feminino , Humanos , Estudos Longitudinais , Masculino , Pessoa de Meia-Idade , Valor Preditivo dos Testes , Adulto Jovem
18.
Transplant Proc ; 42(4): 1061-5, 2010 May.
Artigo em Inglês | MEDLINE | ID: mdl-20534224

RESUMO

After hepatic resection and transplantation with a partial graft, death and regeneration of the hepatocytes coexist in the liver. However, when the functional liver mass is inadequate to ensure a proper balance between regeneration vs functional and metabolic demands, small-for-size syndrome develops. We assessed the early effects of extended hepatic resection on liver function in a rat model. Six male Sprague-Dawley rats underwent 80% resection of the liver, and 6 rats served as a control group. At 6 hours after resection, blood samples were obtained from the hepatic vein for measurement of reduced glutathione (GSH), oxidized glutathione (GSSG), and hepatic venous oxygen saturation (Shvo(2)), and for standard liver function tests including determination of concentrations of alanine aminotransferase (ALT), aspartate aminotransferase (AST), gamma-glutamyl transpeptidase, and total bilirubin. The remnant lobe was removed for GSH assay and histopathologic analysis. In the resection group, values were significantly higher for ALT (P = .002), AST (P = .002), and Shvo(2) (P = .01), whereas a significant decrease was observed for blood GSH (P = .009) but not liver GSH. Also in the resection group, we observed characteristic hepatocyte vacuolization with a gradient from periportal acinar zone 1 to the centrolobular area, the presence of hemorrhagic necrosis, and several leukocyte adhesions. The Shvo(2) and GSH data suggest early alteration of oxygen metabolism, as demonstrated by the reduction in oxygen uptake and decreased liver GSH secretion, with preservation of hepatic GSH. Mitochondrial dysfunction and oxidative injury seem to have a crucial role in early onset of liver damage.


Assuntos
Regeneração Hepática/fisiologia , Transplante de Fígado/fisiologia , Alanina Transaminase/sangue , Animais , Anticonvulsivantes/farmacologia , Aspartato Aminotransferases/sangue , Moduladores GABAérgicos/farmacologia , Hepatectomia , Hepatócitos/citologia , Hepatócitos/fisiologia , Fígado/anatomia & histologia , Fígado/fisiologia , Testes de Função Hepática , Masculino , Mitocôndrias Hepáticas/patologia , Mitocôndrias Hepáticas/fisiologia , Tamanho do Órgão , Sistema Porta/fisiologia , Ratos , Ratos Sprague-Dawley , Tiletamina/farmacologia , Veia Cava Inferior/cirurgia , Zolazepam/farmacologia
20.
Clin Biochem ; 42(16-17): 1654-7, 2009 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-19651118

RESUMO

The present study describes the specific content of ferritin iron, zinc and aluminium in four different groups: 1) hemodialysis hyperferritinemic patients; 2) septic patients; 3) iron overloaded patients with hematologic diseases; and 4) blood donors. In all four groups high levels of aluminium and zinc were found in addition to those of iron. However, the sum of the ferritin ions of the control group is significantly higher than that of the other three groups. Furthermore, while ferritin of hemodialysis patients has the same molecular ratio of metal ions as control group (high Al content vs. Fe and Zn), a lower Al/Fe ratio is found both in septic and hematological patients. The results of the present paper might help to explain the high percentage of hyperferritinemia found in hemodialysis patients also in presence of low transferrin saturation and in absence of inflammatory markers. Moreover, the high content of ions other than iron in the ferritin core leads us to believe that ferritin is not only an iron storage protein but rather a regulator of redox active ions.


Assuntos
Alumínio/sangue , Doadores de Sangue , Ferritinas/sangue , Ferro/sangue , Diálise Renal , Zinco/sangue , Estudos de Casos e Controles , Humanos
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