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1.
Biol Trace Elem Res ; 201(2): 627-635, 2023 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-35305538

RESUMEN

The relationship between trace elements and neurological development is an emerging research focus. We performed a case-control study to explore (1) the differences of 13 trace elements chromium (Cr), manganese (Mn), cobalt (Co), zinc (Zn), arsenic (As), selenium (Se), molybdenum (Mo), cadmium (Cd), stannum (Sn), stibium (Sb), mercury (Hg), titanium (TI), and plumbum (Pb) concentration in whole blood and urine between autism spectrum disorder (ASD) children and their typical development peers, and (2) the association between the 13 trace elements and core behaviors of ASD. Thirty ASD subjects (cases) and 30 age-sex-matched healthy subjects from Baise City, Guangxi Zhuang Autonomous Region, China, were recruited. Element analysis was carried out by inductively coupled plasma-optical emission spectrometry. Autistic behaviors were assessed using Autism Behavior Checklist (ABC), Childhood Autism Rating Scale (CARS), and Children Neuropsychological and Behavior Scale (CNBS). The whole blood concentrations of Mo (p = 0.004), Cd (0.007), Sn (p = 0.003), and Pb (p = 0.037) were significantly higher in the ASD cases than in the controls. Moreover, Se (0.393), Hg (0.408), and Mn (- 0.373) concentrations were significantly correlated between whole blood and urine levels in ASD case subjects. There were significant correlations between whole blood Sb (0.406), Tl (0.365), Mo (- 0.4237), Mn (- 0.389), Zn (0.476), and Se (0.375) levels and core behaviors of ASD. Although the mechanism of trace element imbalance in ASD is unclear, these data demonstrate that core behaviors of ASD may be affected by certain trace elements. Further studies are recommended for exploring the mechanism of element imbalance and providing corresponding clinical treatment measures.


Asunto(s)
Trastorno del Espectro Autista , Trastorno Autístico , Mercurio , Selenio , Oligoelementos , Humanos , Niño , Oligoelementos/análisis , Cadmio/análisis , Estudios de Casos y Controles , Plomo/análisis , China , Selenio/análisis , Manganeso/análisis , Molibdeno/análisis , Estaño/análisis , Mercurio/análisis
2.
Environ Pollut ; 315: 120452, 2022 Dec 15.
Artículo en Inglés | MEDLINE | ID: mdl-36272605

RESUMEN

Metal/loid pollution from shipwrecking activities has drawn significant concern due to their persistent threat to the marine ecosystem and human health. We investigated the spatiotemporal distribution, pollution characteristics, risks, sources, and potential impact of metal/loids in the sediments and seafood in the Bay of Bengal at nearby open beaching shipwrecking yards in Bangladesh. We collected 78 sediments and 208 seafood samples from the exposed and control sites from 2018 to 2020 during the dry and wet seasons. The concentrations of 16 elements, including cadmium, arsenic, lead, chromium, manganese, copper, zinc, iron, tin, antimony, nickel, cobalt, molybdenum, vanadium, selenium, and thallium were measured using validated inductively coupled plasma-mass spectrometry (ICP-MS) methods. Based on the pollution indices (enrichment factor, geoaccumulation index, pollution index, and pollution load index), lead, arsenic, cadmium, selenium, copper, zinc, and tin from the dry season showed higher contaminations compared to the wet and their concentrations were increased from 2018 to 2020 with seasonal fluctuations. Sediment cadmium and arsenic posed relatively higher and moderate ecological risks. Health risk analysis indicated that lead, cadmium, and inorganic arsenic (estimated) in seafood species pose a possible health threat to the general population. Further, there were possible ecological and health risks for the metal/loids in combination based on the ecological risk index in sediment and the hazard index in seafood, respectively. Source apportionment suggested that anthropogenic activities through uncontrolled shipwrecking operations over the last four decades were the largest polluting dominator, contributing 55-77% of the metal/loid concentrations. Therefore, the data may inform mitigation strategies for emission control at the shipwrecking yards to protect marine ecosystems and their local population.


Asunto(s)
Arsénico , Metales Pesados , Selenio , Estaño , Contaminantes Químicos del Agua , Humanos , Arsénico/análisis , Bahías , Cadmio/análisis , Cobre/análisis , Ecosistema , Monitoreo del Ambiente , Sedimentos Geológicos/química , Metales Pesados/análisis , Alimentos Marinos/análisis , Selenio/análisis , Estaño/análisis , Contaminantes Químicos del Agua/análisis , Zinc/análisis
3.
Artículo en Inglés | MEDLINE | ID: mdl-36141460

RESUMEN

Children are highly vulnerable to chemical exposure. Thus, metal and metalloid in infant formulas are a concern, although studies in this regard are still relatively scarce. Thus, the presence of aluminum, arsenic, cadmium, tin, mercury, lead, and uranium was investigated in infant formulas marketed in Brazil by inductively coupled plasma mass spectrometry, and the Target Hazard Quotients (THQ) and Target Cancer Risk (TCR) were calculated in to assess the potential risk of toxicity for children who consume these products continuously. Aluminum ranging from 0.432 ± 0.049 to 1.241 ± 0.113 mg·kg-1, arsenic from 0.012 ± 0.009 to 0.034 ± 0.006 mg·kg-1, and tin from 0.007 ± 0.003 to 0.095 ± 0.024 mg·kg-1 were the major elements, while cadmium and uranium were present at the lowest concentrations. According to the THQ, arsenic contents in infant formulas showed a THQ > 1, indicating potential health risk concerns for newborns or children. Minimal carcinogenic risks were observed for the elements considered carcinogenic. Metabolic and nutritional interactions are also discussed. This study indicates the need to improve infant formula surveillance concerning contamination by potentially toxic and carcinogenic elements.


Asunto(s)
Arsénico , Mercurio , Metaloides , Metales Pesados , Neoplasias , Uranio , Niño , Humanos , Lactante , Recién Nacido , Aluminio/análisis , Arsénico/análisis , Arsénico/toxicidad , Brasil/epidemiología , Cadmio/análisis , Carcinógenos/análisis , Carcinógenos/toxicidad , Salud Infantil , Contaminación de Alimentos/análisis , Intoxicación por Metales Pesados , Fórmulas Infantiles/análisis , Mercurio/análisis , Metaloides/análisis , Metales Pesados/análisis , Receptores de Antígenos de Linfocitos T , Medición de Riesgo , Estaño/análisis , Uranio/análisis
4.
Environ Sci Pollut Res Int ; 29(54): 81804-81829, 2022 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-35739445

RESUMEN

The groundwater resources of mining areas have been in a challenging condition in terms of metal pollution and human health. Therefore, this study investigated the concentration of cobalt (Co), molybdenum (Mo), selenium (Se), tin (Sn), and antimony (Sb) in groundwater samples (wells, qanats, and springs) in a heavily contaminated mining district, South Khorasan, Eastern Iran. Human health risk of the studied metals to target groups was assessed, and water quality of the studied groundwater was investigated in the study area. A total of 367 sampling sites (279 wells, 74 qanats, and 14 springs) in South Khorasan Province were selected to collect the groundwater samples from June to July 2020. Sampling was performed thrice for each sampling point, and hydrochemical parameters were evaluated using a portable multiparameter. Inductively coupled plasma mass spectrometry (ICP-MS) was used to detect the metal concentrations. Results showed an order of Se > Mo > Sn > Co > Sb, and hazard index (HI) demonstrated a warning condition for south of South Khorasan (drinking application), southwest of South Khorasan (Irrigation application), and east and center of South Khorasan (drinking-irrigation application). Hydrochemical parameters showed a classification of "Na + K type" and "Mixed Ca-Mg-Cl type" with an overall group of "Na-Cl-HCO3" for sampled waters. Ficklin-Caboi diagram depicted a classification of "near-neutral low metal," and Schoeller diagram classified studied groundwater as "good" for drinking and irrigation consumptions and "Na-Cl" type based on ion balance diagram. Based on the correlation analysis, positive relationships were recorded among EC, TDS, Cl-, Na+, sulfate, Ca2+, salt, total hardness, Mg2+, ammonia, and K+ measured in the water samples. In essence, arid regions of the world greatly rely upon groundwater resources for drinking and irrigation consumptions, and mining districts with a heavy load of active mines can be a serious threat to the groundwater quality and human health.


Asunto(s)
Agua Subterránea , Selenio , Oligoelementos , Contaminantes Químicos del Agua , Humanos , Oligoelementos/análisis , Selenio/análisis , Antimonio/análisis , Molibdeno/análisis , Amoníaco/análisis , Irán , Estaño/análisis , Monitoreo del Ambiente/métodos , Contaminantes Químicos del Agua/análisis , Agua Subterránea/química , Calidad del Agua , Medición de Riesgo , Sulfatos/análisis , Cobalto/análisis
5.
Se Pu ; 37(1): 21-26, 2019 Jan 08.
Artículo en Chino | MEDLINE | ID: mdl-30693705

RESUMEN

For the determination of organo-tin residues in edible vegetable oil, a method was developed based on gas chromatography-mass spectrometric (GC-MS) with positive chemical ionization (PCI). The edible oil samples were first dissolved by cyclohexane-ethyl acetate (1:1, v/v), and then purified by gel permeation chromatography (GPC). After derivatization by sodium tetraethylborate, the samples were analyzed by GC-MS with PCI source in the single ion monitor (SIM) mode. The seven organo-tin compounds showed good linear relationships in the range of 20-2000 µg/L and the correlation coefficients exceeded 0.99. The limits of quantitation (LOQs) and the average recoveries of the seven organo-tin compounds were 0.3-1.2 µg/kg and 66.2%-103.2%, respectively, and the relative standard deviations were less than 11.5% at three spike levels (0.05, 0.10, and 0.20 mg/kg). The method showed good linearity and high sensitivity and can be used for the determination of organo-tin residues in edible vegetable oil.


Asunto(s)
Contaminación de Alimentos/análisis , Compuestos Organometálicos/análisis , Residuos de Plaguicidas/análisis , Aceites de Plantas/análisis , Estaño/análisis , Cromatografía en Gel , Cromatografía de Gases y Espectrometría de Masas , Verduras
6.
Metab Brain Dis ; 32(1): 195-202, 2017 02.
Artículo en Inglés | MEDLINE | ID: mdl-27581303

RESUMEN

The objective of the study was to investigate hair trace elements content in children suffering from autism spectrum disorder (ASD). A total of 74 ASD children and 74 sex- and age-matched controls divided into two age groups (2-4 and 5-9 years) were investigated. Hair trace elements content was assessed using inductively coupled plasma mass spectrometry. A general cohort of ASD children was characterized by 29 %, 41 %, and 24 % lower hair levels of chromium (Cr), iodine (I), and vanadium (V), respectively, whereas the level of selenium (Se) exceeded the respective control values by 31 %. In ASD children aged 2-4 years hair Cr, I and V content was 68 %, 36 % and 41 % lower than in the controls. Older ASD children were characterized by 45 % increase in hair Se levels. In a general cohort of ASD children hair beryllium (Be) and tin (Sn) levels were 50 % and 34 % lower than the control values. In the first age group (2-4 years) of ASD children 34 %, 42 %, and 73 % lower levels of arsenic (As), boron (B), and Be were detected. In the second age group of ASD children only a nearly significant 25 % decrease in hair lead (Pb) was detected. Surprisingly, no significant group difference in hair mercury (Hg), zinc (Zn), and copper (Cu) content was detected. Generally, the results of the present study demonstrate that children with ASD are characterized by lower values in hair of not only essential but also toxic trace elements.


Asunto(s)
Trastorno del Espectro Autista , Cabello/química , Oligoelementos/análisis , Arsénico/análisis , Niño , Preescolar , Cromo/análisis , Cobre/análisis , Femenino , Humanos , Yodo/análisis , Masculino , Mercurio/análisis , Selenio/análisis , Estaño/análisis , Vanadio/análisis , Zinc/análisis
7.
Chemosphere ; 168: 786-797, 2017 Feb.
Artículo en Inglés | MEDLINE | ID: mdl-27836270

RESUMEN

This study investigates the geochemical characteristics of recent shallow-water aragonite-rich sediments from the karstic marine lakes located in the pristine environment on the island of Mljet (Adriatic Sea). Different trace elements were used as authigenic mineral formation, palaeoredox and pollution indicators. The distribution and the historical record of trace elements deposition mostly depended on the sedimentological processes associated with the formation of aragonite, early diagenetic processes governed by the prevailing physico-chemical conditions and on the recent anthropogenic activity. This study demonstrated that Sr could be used as a proxy indicating authigenic formation of aragonite in a marine carbonate sedimentological environment. Distribution of the redox sensitive elements Mo, Tl, U and Cd was used to identify changes in redox conditions in the investigated lake system and to determine the geochemical cycle of these elements through environmental changes over the last 100 years. The significant enrichment of these elements and the presence of early formed nanostructured authigenic framboidal pyrite in laminated deeper parts of sediment in Malo Jezero, indicate sporadic events of oxygen-depleted euxinic conditions in the recent past. Concentrations of trace elements were in the range characteristic for non-contaminated marine carbonates. However, the increase in the concentrations of Zn, Cu, Pb, Sn, Bi in the upper-most sediment strata of Veliko Jezero indicates a low level of trace element pollution, resulting from anthropogenic inputs over the last 40 years. The presence of butyltin compounds (BuTs) in the surface sediment of Veliko Jezero additionally indicates the anthropogenic influence in the recent past.


Asunto(s)
Carbonato de Calcio/análisis , Monitoreo del Ambiente , Sedimentos Geológicos/química , Lagos/química , Estroncio/análisis , Oligoelementos/análisis , Contaminación del Agua/análisis , Bismuto/análisis , Cadmio/análisis , Carbonato de Calcio/química , Cobre/análisis , Hierro , Región Mediterránea , Minerales , Molibdeno/análisis , Oxidación-Reducción , Sulfuros , Estaño/análisis , Titanio/análisis , Uranio/análisis , Zinc/análisis
8.
Environ Monit Assess ; 185(8): 6407-12, 2013 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-23232849

RESUMEN

The presence of heavy metals in the environment could constitute a hazard to food security and public health. These can be accumulated in aquatic animals such as fish. In the present paper, three heavy metals (mercury, selenium, and tin) in canned products produced and sold in Iran were studied: longtail tuna, Kawakawa, Kilka, and yellowfin tuna were determined using inductively coupled plasma-optical emission spectrometer and a direct mercury analyzer. Analytical results were validated by spiking the samples with various concentrations of these metals to test recovery. The metal contents, expressed in micrograms per gram, wet weight, varied depending upon the species studied. The levels of Hg ranged from 0.0003 to 0.408 µg/g, the levels of Sn ranged from 0.036 to 0.480 µg/g, while the levels of Se ranged from 0.130 to 4.500 µg/g. Comparative evaluation of these metals in different brands of canned fish showed that the average concentrations of Hg, Sn, and Se of all species is significantly lower than adverse level for the species themselves and for human consumption when compared with FAO/WHO permissible limits. Therefore, their contribution to the total body burden of these heavy metals can be considered as negligibly small.


Asunto(s)
Contaminación de Alimentos/análisis , Mercurio/análisis , Alimentos Marinos/análisis , Selenio/análisis , Estaño/análisis , Contaminantes Químicos del Agua/análisis , Contaminación de Alimentos/estadística & datos numéricos , Conservación de Alimentos , Irán , Alimentos Marinos/estadística & datos numéricos , Contaminación Química del Agua/estadística & datos numéricos
9.
Artículo en Inglés | MEDLINE | ID: mdl-19736595

RESUMEN

The dissolution of iron and tin from tinplate cans filled with tomato purée (pH 4.34) and dioctyl sebacate oil (DOS), essential onion oil (EOO) or potassium nitrate was studied using atomic absorption spectroscopy (AAS), while nitrate was determined using high-performance liquid chromatography (HPLC). The maximum values found in cans were up to 284 mg kg(-1) for tin and 513 mg kg(-1) for iron at elevated storage temperature. Results indicated that the addition of EOO to tomato purée prevents the corrosion process in the case of tin, where concentrations were lowered from 223 to 28 mg kg(-1) for cans with DOS oil and EOO at 20 degrees C, respectively (inhibition rate of 87%). On the other hand, the presence of EOO enhanced the corrosion process for iron increasing the concentration from 15 to 46 mg kg(-1) during 7 months of storage, although this value did not exceed maximum permitted value (50 mg kg(-1)). In cans with tomato purée and potassium nitrate, dissolution of tin started after 30 (36 degrees C) and 60 (20 degrees C) days of storage as a consequence of nitrate action, which act as a corrosion accelerator. Since the addition of EOO improves the taste of canned tomato purée, its potential use as a corrosion inhibitor would be of interest.


Asunto(s)
Contaminación de Alimentos/análisis , Embalaje de Alimentos , Solanum lycopersicum , Estaño/química , Cromatografía Líquida de Alta Presión/métodos , Corrosión , Análisis de los Alimentos/métodos , Humanos , Hierro/análisis , Aceites de Plantas/química , Espectrofotometría Atómica/métodos , Sulfuros/química , Estaño/análisis
10.
Environ Pollut ; 155(2): 320-6, 2008 Sep.
Artículo en Inglés | MEDLINE | ID: mdl-18086510

RESUMEN

Mangrove and halophytic plants occur along the coastal areas of Tamil Nadu, south India and these plants have been used in traditional medicine for centuries. Heavy metals are known to pose a potential threat to terrestrial and aquatic biota. However, little is known on the toxic levels of heavy metals found in mangrove and halophytic plants that are used in traditional medicine in India. To understand heavy metal toxicity, we investigated the bioconcentration factors (BCF) of heavy metals in leaves collected from eight mangroves and five halophytes in the protected Pichavaram mangrove forest reserve in Tamil Nadu State, south India. Data presented in this paper describe the impact of essential (Cu, Fe, Mg, Mn and Zn) and non-essential/environmentally toxic trace metals (Hg, Pb and Sn) in mangrove and halophytic medicinal plants. The concentrations of Pb among 13 plant species were higher than the normal range of contamination reported for plants. The average concentration of Hg in the halophytic plants (0.43+/-0.37 microg/g) was seven times higher than mangrove plants (0.06+/-0.03 microg/g) and it indicated pollutants from industrial sources affecting halophytes more than mangroves.


Asunto(s)
Conservación de los Recursos Naturales , Metales Pesados/análisis , Hojas de la Planta/química , Plantas Medicinales , Contaminantes Químicos del Agua/análisis , Humedales , Cobre/análisis , Monitoreo del Ambiente/métodos , Agua Dulce , India , Hierro/análisis , Plomo/análisis , Magnesio/análisis , Manganeso/análisis , Mercurio/análisis , Estaño/análisis , Zinc/análisis
11.
Artículo en Inglés | MEDLINE | ID: mdl-15756965

RESUMEN

Concentrations of 34 metals were determined in the concentrated waste activated sludge from a dissolved air flotation unit at an advanced municipal wastewater treatment plant (WWTP) with biological nutrient removal. Reduction in enhanced biological phosphorus removal (EBPR) efficiency was observed at total tin concentrations greater than 4 microg L(-1) in the solids fraction of the mixed liquor suspended solids. No influence on carbon or nitrogen removal efficiency was found by elevated tin concentrations. Other process control variables and metal concentrations were not correlated with reduced EBPR efficiency on dates with elevated tin levels. The known high contributions of organotin species toward total tin in activated sludges from other municipal WWTPs, and the high toxicity of these compounds, suggests elevated organotin levels may be responsible for the observed reduction in EBPR efficiency.


Asunto(s)
Fósforo/aislamiento & purificación , Estaño/química , Eliminación de Residuos Líquidos , Purificación del Agua , Colombia Británica , Carbono/aislamiento & purificación , Metales/análisis , Nitrógeno/aislamiento & purificación , Oxígeno/análisis , Aguas del Alcantarillado/análisis , Estaño/análisis
12.
Nature ; 432(7013): 35-6, 2004 Nov 04.
Artículo en Inglés | MEDLINE | ID: mdl-15525972

RESUMEN

The discovery of a small tin canister in London during archaeological excavations of a Roman temple precinct, dated to the middle of the second century AD, is a landmark in the study of this class of artefact. Such discoveries from the Roman world are rare and this is the only one to be found so far with its lid and contents--a whitish medicinal or cosmetic cream--providing a unique opportunity for us to study the ancient formulation.


Asunto(s)
Cosméticos/química , Cosméticos/historia , Mundo Romano , Animales , Arqueología , Ácidos Grasos/análisis , Cromatografía de Gases y Espectrometría de Masas , Historia Antigua , Londres , Espectroscopía Infrarroja por Transformada de Fourier , Almidón/análisis , Estaño/análisis
13.
Guang Pu Xue Yu Guang Pu Fen Xi ; 23(3): 594-6, 2003 Jun.
Artículo en Chino | MEDLINE | ID: mdl-12953551

RESUMEN

A new spectrophotometric method for the determination of trace amount of tin (IV) has been developed based on the reaction of Sn (IV) with o-cresolphthalexon (XO), which forms a stable complex in the presence of polyvinyl alcohol (PVA). The complex exhibited a maximum absorbance at 544 nm. The molar absorption coefficient was 4.38 x 10(5) L.mol-1.cm-1. Recovery factor ranged from 97.4%-101.1%. Beers law was obeyed in the range of Sn 0.1-5 micrograms.(25 mL)-1. The complex was stable within 6 h. The suitable conditions for the reaction were investigated. The developed method has been applied to the determination of Sn (IV) in water samples. The result obtained is satisfactory.


Asunto(s)
Residuos Industriales/análisis , Espectrofotometría Ultravioleta/métodos , Estaño/análisis , Contaminantes Químicos del Agua/análisis , Fenolftaleínas/química , Alcohol Polivinílico/química , Selenio/química , Sensibilidad y Especificidad , Tensoactivos
14.
Analyst ; 125(12): 2223-9, 2000 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-11219056

RESUMEN

In order to estimate metal distribution patterns in biomolecules of different sizes and their possible relationship with environmental heavy metal contamination, multi-elemental distributions in different fractions of the cytosols of mussels were studied. To do so, samples were collected from natural populations of two coastal regions in Spain: a wild (uncontaminated) coast and an industrialised (contaminated) area in Asturias. Moreover, some commercial mussels from the Galicia coast were also investigated for comparison. Aliquots of the mussel cytosol extracts from each sample were applied to a calibrated Sephadex G-75 column (100 x 1 cm) and forty 3 ml fractions were obtained. After suitable dilution, 18 trace metals were determined by double focusing inductively coupled plasma mass spectrometry (DF-ICP-MS). The use of DF-ICP-MS detection allowed the resolution of several spectral interferences that cannot be resolved by quadrupole ICP-MS. Accurate results for ultratrace elements at basal levels are possible even after sample dilution to prevent matrix effects. After biomolecule-metal association pattern has been established, quantitative analysis of mussel cytosols from the three coastal areas was carried out, using external aqueous calibration plus standard additions to correct for possible matrix effects. Results showed that total metal contents increased following the expected order: wild coast < Galicia coast < industrial area coast. Speciation of Cu, Zn, Ca, U, Ni, Mo, Mn, Cr, V, Cd, Al and Sb showed a similar distribution pattern among cytosolic ligands for all the studied samples. Conversely, Fe, Pb, Sn, Co, Hg and Ag were found to exhibit different speciation patterns when samples from industrialised (contaminated) and non-industrialised areas were compared.


Asunto(s)
Bivalvos/química , Contaminación de Alimentos/análisis , Metales/análisis , Aluminio/análisis , Animales , Antimonio/análisis , Cadmio/análisis , Calcio/análisis , Cromo/análisis , Cobalto/análisis , Cobre/análisis , Citosol/química , Hierro/análisis , Plomo/análisis , Manganeso/análisis , Espectrometría de Masas/métodos , Mercurio/análisis , Molibdeno/análisis , Níquel/análisis , Plata/análisis , España , Estaño/análisis , Uranio/análisis , Vanadio/análisis , Zinc/análisis
15.
Mutat Res ; 443(1-2): 157-81, 1999 Jul 15.
Artículo en Inglés | MEDLINE | ID: mdl-10415439

RESUMEN

Humans have been in contact with metals almost since the beginning of our existence. In fact, one cannot even think on human evolution without considering the great role played by metals in mankind's development. Metals are common moieties of molecules involved in a wide variety of biological processes, and hence are found in virtually all living organisms. Some metals are essential for human nutrition; others are found as contaminants in foodstuffs. One feature of the normal human diet which is frequently found is the simultaneous presence of both essential and toxic metals. Other factors important in the risk-evaluation analysis of metals are their pharmacokinetics, interactions among them and with other major components of the diet, and, especially, the great differences in the dietary habits of different populations and in the regional distribution of metals. In attempting to understand the role which dietary metals could play in human carcinogenesis, we found that the many factors involved and the lack of specific information made it difficult to reach firm conclusions on the hazards of dietary metals. We hope that this paper will raise the interest of genetic toxicologists in the subject and will consequently facilitate a risk analysis of the carcinogenic potential of dietary metals.


Asunto(s)
Carcinógenos/análisis , Dieta , Contaminación de Alimentos , Metales/efectos adversos , Metales/análisis , Mutágenos/análisis , Arsénico/análisis , Arsénico/toxicidad , Cadmio/análisis , Cadmio/toxicidad , Cromo/análisis , Cromo/toxicidad , Humanos , Plomo/análisis , Plomo/toxicidad , Mercurio/análisis , Mercurio/toxicidad , Mutágenos/toxicidad , Níquel/análisis , Níquel/toxicidad , Selenio/análisis , Selenio/toxicidad , Estaño/análisis , Estaño/toxicidad , Vanadio/análisis , Vanadio/toxicidad , Zinc/análisis , Zinc/toxicidad
16.
J Anal Toxicol ; 23(2): 108-12, 1999.
Artículo en Inglés | MEDLINE | ID: mdl-10192414

RESUMEN

An atomic-absorption spectrometric method is described for the determination of tin, vanadium, iron, and molybdenum in two certified reference materials, food samples, and petroleum crude. After treatment with acids, these elements are separated from matrix elements by simultaneous solvent extraction of 5,5'-methylenedisalicylohydroxamic acid complexes from HCl/NaClO4 solution into an isobutyl methyl ketone/tributyl phosphate solution. The detection limits range from 0.018 to 0.19 microg/mL (n = 3), and the relative standard deviations do not exceed 2.0% at levels of 0.5, 0.6, 2.0, and 7.0 microg/mL of Fe, Mo, V, and Sn, respectively. The method is selective and suffers only from interference by Zr(IV), Ti(IV), Th(IV), W(VI), PO4(3-), and F-.


Asunto(s)
Contaminación de Alimentos , Metales/análisis , Petróleo/análisis , Espectrofotometría Atómica/métodos , Calibración , Interacciones Farmacológicas , Concentración de Iones de Hidrógeno , Iones , Hierro/análisis , Molibdeno/análisis , Sensibilidad y Especificidad , Estaño/análisis , Vanadio/análisis
17.
Sci Total Environ ; 227(1): 69-72, 1999 Feb 16.
Artículo en Inglés | MEDLINE | ID: mdl-10209881

RESUMEN

Metallic teapots traditionally used in Morocco were investigated for release of toxic metals from the teapots and their toxicity, as determined by MetPAD, a bacterial toxicity test that is specific for heavy metal toxicity. Our data show that some teapots were non-toxic while a few others were highly toxic, as shown by MetPAD. Tea addition reduced somewhat heavy metal toxicity due possibly to the complexing ability of tea. Chemical analysis of teapot leachates showed that some contained zinc and copper. Teapot No. 5, which showed the highest toxicity, also displayed the highest Zn concentration (7.39 mg/l), confirming the toxicity data. Based on estimates of tea consumption in Morocco, we showed that the extra daily burden of Zn ranged from 1.75 to 4.2 mg/day, assuming the maximum zinc concentration of 7.4 mg/l, as found in our study. This represents 3.5-8% of the LOAEL for zinc of 50 mg/day and would not be important as compared to other sources zinc intake.


Asunto(s)
Utensilios de Comida y Culinaria , Contaminación de Alimentos/análisis , Metales Pesados/análisis , Té/química , Cromo/efectos adversos , Cromo/análisis , Cobre/efectos adversos , Cobre/análisis , Humanos , Metales Pesados/efectos adversos , Marruecos , Níquel/efectos adversos , Níquel/análisis , Té/efectos adversos , Estaño/efectos adversos , Estaño/análisis , Zinc/efectos adversos , Zinc/análisis
18.
J Prosthet Dent ; 77(4): 405-13, 1997 Apr.
Artículo en Inglés | MEDLINE | ID: mdl-9104718

RESUMEN

STATEMENT OF PROBLEM: The high reactivity of fluoride agents used in topical fluoride treatments have raised important questions on their potential adverse effects on restorative materials. PURPOSE: The purpose of this study was to evaluate the effect of topical fluoride agents used for office or home treatments on the surface morphologic characteristics and composition of composite restoratives. MATERIAL AND METHODS: The fluorides used were Act, Phosflur, Gel II, Prevident, Stop, Butler APE, Nupro, and Omni Gel & Rinse. The composites tested were Brilliant DI, Heliomolar Ro, Herculite XRV, and P-50. The pH of the fluorides was measured as received and after dilution with water at a 1:3 volume ratio. The composites were subjected to the fluoride treatments until the total number of applications simulated the equivalent of 4 years under treatment. The changes induced on the surface morphologic features and composition of the restoratives were assessed by multiple internal reflectance Fourier transform infrared spectroscopy, scanning electron microscopy, and x-ray microanalysis. RESULTS: All fluorides showed an acidic pH that was not significantly changed after dilution, except Stop, which exhibited a significant pH reduction. All fluorides increased the amount of loosely bound water in the composite matrix. Butler APF gel was the most aggressive for Brilliant DI and Herculite XRV, leading to excessive surface degradation, porosity, destruction of the filler-matrix interface, filler dissolution, and debonding. A reduction in the extent of remaining C = C bonds was observed in Herculite XRV after Butler APF treatment; Phosflur, Gel II, and Prevident had a milder effect. Treatment of Brilliant Dl and Herculite XRV with Omni Gel & Rinse resulted in the formation of a stable precipitation layer rich in barium, phosphorus, tin, oxygen, and fluoride. P-50 was severely affected at the resin-matrix interface after Stop treatment, whereas Omni Gel & Rinse induced fewer surface changes. Heliomolar Ro was the least affected restorative regardless of the type of fluoride used.


Asunto(s)
Cariostáticos/química , Resinas Compuestas/química , Restauración Dental Permanente , Fluoruros Tópicos/química , Fluoruro de Fosfato Acidulado/química , Resinas Acrílicas/química , Bario/análisis , Bisfenol A Glicidil Metacrilato/química , Fenómenos Químicos , Precipitación Química , Química Física , Dentífricos/química , Microanálisis por Sonda Electrónica , Fluoruros/análisis , Geles/química , Concentración de Iones de Hidrógeno , Ensayo de Materiales , Microscopía Electrónica de Rastreo , Antisépticos Bucales/química , Oxígeno/análisis , Fósforo/análisis , Poliuretanos/química , Porosidad , Cementos de Resina/química , Solubilidad , Espectroscopía Infrarroja por Transformada de Fourier , Propiedades de Superficie , Estaño/análisis , Agua
19.
Zhongguo Zhong Yao Za Zhi ; 17(6): 342-3, 382, 1992 Jun.
Artículo en Chino | MEDLINE | ID: mdl-1418577

RESUMEN

Uniform design has been applied to select the optimum technological conditions for processing Heixi in Shenrong Heixi Pills, using the contents of the main constituent of Heixi SNS as the optimum target. The best technological conditions have thus been found.


Asunto(s)
Materia Medica/química , Sulfuros/análisis , Compuestos de Estaño , Estaño/análisis , Calor , Microcomputadores , Tecnología Farmacéutica
20.
Z Lebensm Unters Forsch ; 193(4): 351-5, 1991 Oct.
Artículo en Inglés | MEDLINE | ID: mdl-1767596

RESUMEN

Sodium, potassium, arsenic, selenium and tin have been determined in 38 different types of domestic and imported fresh fruits. All samples (n = 242) were analysed for Na und K whereas a limited number of samples (n = 85) of each fruit type was selected for the determination of As, Se and Sn. The median contents, in mass fractions of the edible portion, found for fresh fruits are: Na less than 0.001%; K 0.17%; As 4 micrograms/kg; Se 2 micrograms/kg and Sn less than 0.05 mg/kg. The corresponding 90th percentile values are: Na 0.002%, K 0.34%; As 12 micrograms/kg; Se 10 micrograms/kg and Sn 0.10 mg/kg. Results for selenium reported here differ substantially from those given for a number of fresh fruits in the German Food Composition Tables 1986/1987. The average consumption of 129 g fresh fruit by Dutch citizens in the age category of 22-75 years contributes, in general, marginally to the total daily dietary intake of sodium, arsenic, selenium and tin. Fresh fruit can contribute substantially, up to 23%, to the average oral daily intake of potassium.


Asunto(s)
Arsénico/análisis , Electrólitos/análisis , Frutas/química , Selenio/análisis , Estaño/análisis , Contaminación de Alimentos/análisis , Potasio/análisis , Sodio/análisis
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