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1.
Eur J Appl Physiol ; 112(8): 3027-31, 2012 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-22179857

RESUMEN

Cadmium (Cd), tungsten (W), tellurium (Te), beryllium (Be), and lead (Pb), are non-essential metals pervasive in the human environment. Studies on athletes during training periods compared to non-training control subjects, indicate increased loss of minerals through sweat and urine. The aim of this study was to compare the level of these trace elements, determined by inductively coupled plasma mass spectrometry (ICP-MS) in urine samples, between athletes and age-matched sedentary subjects living in the same geographical area, although anthropometric and cardiovascular measurements showed that athletes have significantly (P ≤ 0.001) lower BMI, body fat and heart rate, whereas the muscle and bone percentage was significantly (P ≤ 0.001) higher than in sedentary subjects. The validity of the methodology was checked by the biological certified reference material. Trace element analysis concentrations, expressed in µg/mg creatinine, of five toxic elements in urine from athletes (n = 21) versus sedentary subjects, (n = 26) were as follows: Cd (0.123 ± 0.075 vs. 0.069 ± 0.041, P ≤ 0.05); W (0.082 ± 0.053 vs. < limit of detection); Te (0.244 ± 0.193 vs. 0.066 ± 0.045, P ≤ 0.001), Be (0.536 ± 0.244 vs. 0.066 ± 0.035, P ≤ 0.001); Pb (0.938 ± 0.664 vs. 2.162 ± 1.444 P ≤ 0.001). With the exception of Pb, urine toxic metal concentrations from athletes were higher than from sedentary subjects. This fact suggests that physical activity counteracts, at least in part, the cumulative effect of toxic environment by increasing the urine excretion of toxic metals in trained people.


Asunto(s)
Atletas , Contaminantes Ambientales/toxicidad , Contaminantes Ambientales/orina , Metales/toxicidad , Metales/orina , Conducta Sedentaria , Adolescente , Adulto , Antropometría , Berilio/toxicidad , Berilio/orina , Biomarcadores/orina , Composición Corporal , Índice de Masa Corporal , Cadmio/toxicidad , Cadmio/orina , Ambiente , Conducta Alimentaria , Humanos , Plomo/toxicidad , Plomo/orina , Masculino , Espectrometría de Masas/normas , Estándares de Referencia , Reproducibilidad de los Resultados , Características de la Residencia , Carrera , España , Telurio/toxicidad , Telurio/orina , Tungsteno/toxicidad , Tungsteno/orina , Adulto Joven
2.
Occup Med (Lond) ; 61(2): 132-5, 2011 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-21183571

RESUMEN

BACKGROUND: Few studies have considered garlic odour as a socially important outcome of occupational tellurium (Te) exposure or concurrent exposures, and most known guidelines focus on other signs and symptoms (e.g. weight loss and somnolence). This study considers workers exposed to tellurium and selenium (Se) at an Ontario, Canada silver refinery. AIMS: To establish the relation of urinary tellurium concentrations to reporting garlic odour, while considering other work-related factors such as concurrent urinary selenium concentrations. METHODS: Historical surveillance records of urinary analyses for tellurium and selenium concentrations (µmol Te or Se/mol creatinine in urine) and symptom self-reports were used. Records were available from December 1986 to June 2002. Logistic regression models were fitted using age at sampling, tellurium and selenium urine concentration and duration of employment. Individual main effects were age adjusted and the final model was fitted for tellurium and selenium urine concentration and duration of employment. RESULTS: Urinary tellurium concentration was significantly associated with garlic odour reporting (odds ratio = 1.74, 95% confidence interval 1.01-2.97, P < 0.05). Furthermore, the likelihood of reporting garlic odour rose as workers reached urinary tellurium concentrations >1 µmol/mol creatinine. CONCLUSIONS: Tellurium urinary concentrations of <1 µmol/mol creatinine appear to limit, but not eliminate, the likelihood of reporting garlic odour. Future studies should consider the effect of concurrent selenium exposure as well as other workplace factors and hygiene.


Asunto(s)
Ajo , Exposición Profesional/estadística & datos numéricos , Odorantes , Selenio/orina , Telurio/orina , Adulto , Factores de Edad , Empleo , Femenino , Humanos , Modelos Logísticos , Masculino , Persona de Mediana Edad , Exposición Profesional/análisis , Ontario , Autoinforme , Plata , Factores de Tiempo
6.
J Trace Elem Electrolytes Health Dis ; 5(4): 239-44, 1991 Dec.
Artículo en Inglés | MEDLINE | ID: mdl-1822332

RESUMEN

As tellurium ranks among the rare non-essential trace elements there is only little known of its intestinal absorption and its metabolic behaviour in humans. Data for risk evaluations needed for occupational medicine are based on animal experiments only. In order to investigate the metabolic behaviour of tellurium in man, tellurium in different forms was administered perorally to healthy male human volunteers. It was given as sodium tellurate, sodium tellurite, metallic colloid and intrinsically bound in cress. For the latter, cress was cultivated with tellurium-containing water in order to provide tellurium for ingestion in a form which is more equivalent to foodstuffs. After the administration the urinary excretion of tellurium was determined. Tellurium concentrations were measured in urine samples by means of graphite furnace atomic absorption spectroscopy (GFAAS) after wet ashing and a preconcentration of tellurium by solvent extraction with isobutyl methyl ketone (IBMK). From the cumulative tellurium excretion in the first four days after the administration, a percentage intestinal absorption of 25% +/- 10% for soluble tellurium salts can be calculated. The renal tellurium excretion is faster after administration of hexavalent tellurium than after ingestion of the tetravalent form. This can explain the higher toxicity of the tetravalent tellurium compounds found in animal experiments. The introduction of tellurium to cress lowered the intestinal absorption to approximately 15%. For metallic tellurium the fractional intestinal absorption was found to be about 10%.


Asunto(s)
Telurio/orina , Adulto , Humanos , Absorción Intestinal , Masculino , Telurio/administración & dosificación , Telurio/farmacocinética
7.
Anal Chem ; 66(8): 1316-22, 1994 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-8210046

RESUMEN

The antitumor drug AS-101 [ammoniumtrichloro (dioxoethylene-O,O')tellurate(IV)] is the first tellurium-containing compound that has been identified as possessing immunomodulating properties and minimal toxicity. We have developed a stable isotope dilution gas chromatography/mass spectrometry method using 120Te as an internal standard and (4-fluorophenyl)magnesium bromide as a derivatizing agent for Te determination in urine. The urine samples were digested using HNO3 + H2O2 prior to derivatization with lithium bis(trifluoroethyl)dithiocarbamate at a pH of 3. The trifluorodiethyldithiocarbamate of tellurium was reacted with the Grignard reagent in anhydrous diethyl ether to obtain Te-(FC6H4)2 for GC/MS analysis. All isotope ratio measurements were made by selected ion monitoring with a Finnigan MAT 8230 organic mass spectrometer using a 10-m fused silica capillary column. Overall percision values for the five major Te isotopes relative to 130Te were 0.6-3.1% when 10-ng samples of chelated Te were analyzed. No appreciable memory or carry-over effect was observed when two synthetic mixtures differing in 120Te:130Te ratios by a factor of 50 were sequentially analyzed. The isotope dilution GC/MS method was validated by determining Te in urine samples and comparing the values with electrothermal atomic absorption spectrometry. Te concentrations were determined in the 100-500 micrograms/L range with CVs of 1-4%.


Asunto(s)
Telurio/orina , Cromatografía de Gases y Espectrometría de Masas , Humanos , Indicadores y Reactivos , Espectrofotometría Atómica
8.
Int Arch Occup Environ Health ; 69(3): 219-23, 1997.
Artículo en Inglés | MEDLINE | ID: mdl-9049674

RESUMEN

OBJECTIVE: An analytical method has been established to determine the concentration of antimony (Sb), bismuth (Bi), lead (Pb), cadmium (Cd), mercury (Hg), Palladium (Pd), platinum (Pt), tellurium (Te), tin (Sn), thallium (Tl) and tungsten (W) in urine. The aim was to develop a method which is equally suitable for the determination of environmentally as well as occupationally caused metal excretion. METHODS: Inductively coupled plasma-mass spectroscopy (ICP-MS) was used for the determination of metals. Calibration was done using aqueous solutions and standard addition respectively. RESULTS: Urine samples of 14 persons occupationally non-exposed to metals were analysed. With the exception of Pt and Bi all the metals were found in these urine samples. The detection limits for these metals lie between 5 and 50 ng/l. CONCLUSIONS: For some metals, which are important from an occupational as well as an environmental viewpoint, ICP-MS is more sensitive than atomic absorption spectrometry (AAS). ICP-MS, moreover, is welcome as a reference method for AAS with the additional advantage of multi-element measurement.


Asunto(s)
Espectrometría de Masas/métodos , Metales Pesados/orina , Exposición Profesional/análisis , Adulto , Antimonio/orina , Bismuto/orina , Cadmio/orina , Calibración , Femenino , Humanos , Plomo/orina , Masculino , Mercurio/orina , Metales Pesados/normas , Persona de Mediana Edad , Paladio/orina , Platino (Metal)/orina , Reproducibilidad de los Resultados , Sensibilidad y Especificidad , Estadística como Asunto , Telurio/orina , Talio/orina , Estaño/orina , Tungsteno/orina
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