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1.
Gac. sanit. (Barc., Ed. impr.) ; 36(2): 173-183, mar./abr. 2022. ilus, tab
Artículo en Inglés | IBECS | ID: ibc-209198

RESUMEN

Objective: What are the levels of asbestos exposure that cause each type of health effect? The objective of this study was to review the available scientific evidence on exposure levels for asbestos and their relationship to health effects. Method: An umbrella review of English-language reviews and meta-analyses, from 1980 to March 2021 was conducted. We included reviews involving quantified asbestos exposures and health outcomes. The review has been adapted to the indications of the PRISMA declaration. Methodological quality of the selected studies was assessed using the AMSTAR instrument. Results: We retrieved 196 references. After applying the search strategy and quality analysis, 10 reviews were selected for in-depth analysis. For lung cancer, the highest risk was observed with exposure to amphiboles. Longer, thinner fibers had the greatest capacity to cause lung cancer, especially those > 10 μm in length. For mesothelioma, longer and thinner fibers were also more pathogenic; amphiboles ≥ 5 μm are especially associated with increased mesothelioma risk. No studies observed an increased risk for lung cancer or mesothelioma at asbestos exposure levels <0.1 f/ml. No reviews provided information on exposure concentrations for pulmonary fibrosis. Currently, there is limited evidence in humans to establish the causal relationship between gastrointestinal cancer and asbestos exposure. Conclusions: Banning all asbestos exposure remains the best measure to preventing its negative health effects. The highest quality reviews and meta-analyses support that there is little risk of lung cancer or mesothelioma at daily exposure levels below 0.1 f/ml. (AU)


Objetivo: Revisar la evidencia científica disponible sobre los niveles de exposición al asbesto y su relación con los efectos sobre la salud. Método: Se realizó una revisión de revisiones sistemáticas y metaanálisis en inglés, desde 1980 hasta marzo de 2021. Se incluyeron revisiones que involucran exposiciones cuantificadas al asbesto y resultados de salud. La revisión se adaptó a las indicaciones de la Declaración PRISMA. La calidad metodológica de los estudios seleccionados fue evaluada mediante el instrumento AMSTAR. Resultados: Se recuperaron 196 referencias y tras aplicar la estrategia de búsqueda y analizar la calidad se seleccionaron 10 revisiones para un análisis en profundidad. Para el cáncer de pulmón, se observó mayor riesgo con la exposición a anfíboles. Las fibras más largas y delgadas presentaron mayor capacidad de causar cáncer de pulmón, especialmente aquellas de longitud >10μm. Para el mesotelioma, las fibras más largas y delgadas también fueron más patógenas; los anfíboles ≥ 5μm se asociaron con un mayor riesgo de mesotelioma. Ningún estudio observó mayor riesgo de cáncer de pulmón o de mesotelioma con niveles de exposición al asbesto <0,1 f/ml. Ningún estudio proporcionó información sobre concentraciones de exposición para la fibrosis pulmonar. Actualmente existe evidencia limitada en humanos para establecer la relación causal entre la exposición al asbesto y el cáncer gastrointestinal. Conclusiones: Prohibir toda exposición al asbesto es la mejor medida para prevenir sus efectos negativos para la salud. Las revisiones y metaanálisis de más alta calidad respaldan que hay escaso riesgo de cáncer de pulmón y de mesotelioma con niveles de exposición diaria por debajo de 0,1 f/ml. (AU)


Asunto(s)
Historia del Siglo XX , Historia del Siglo XXI , Amianto , Límite Permisible de Riesgos Laborales , Fibrosis Pulmonar , Neoplasias Pulmonares , Neoplasias Gastrointestinales , Mesotelioma
2.
Int J Occup Med Environ Health ; 33(5): 611-620, 2020 Sep 17.
Artículo en Inglés | MEDLINE | ID: mdl-32699425

RESUMEN

OBJECTIVES: Setting and implementing occupational exposure limits (OELs) is one of the measures taken to protect workers from adverse effects of hazardous chemicals. The EU Regulation on Registration, Evaluation, Authorisation and Restriction of Chemicals (REACH) introduced an additional kind of exposure guidance values for workers; namely, the derived no effect level (DNEL) for workers' inhalation exposure (worker DNEL). About 500 substances have a Swedish OEL, while roughly 5000 substances have a worker DNEL derived by REACH registrants. This work aims to investigate how the Swedish OELs and worker DNELs are perceived at Swedish workplaces, and whether worker DNELs are considered a possible alternative to OELs when the latter are lacking. MATERIAL AND METHODS: An online questionnaire was designed and sent to Swedish companies identified through the European Chemicals Agency's database of registered substances (N = 126) and the Swedish Chemicals Agency's registry of companies that import or manufacture notifiable chemical products (N = 227). The response rates were 52% and 38%, respectively. RESULTS: The respondents stated that they were using the Swedish OELs and most of them considered these to be a suitable risk management tool. As about one-third of the respondents expressed that they had some experience in using substances without the Swedish OELs, there are certain data gaps that worker DNELs may fill. One-third of the respondents familiar with worker DNELs stated that they would consider using worker DNELs for substances without the Swedish OELs. However, nearly half of the respondents reported to be unfamiliar with worker DNELs. CONCLUSIONS: Poor familiarity with DNELs may pose an obstacle to properly recognizing DNELs' potential as well as the possible limitations of individual DNELs. There is a need for education about DNELs, as well as for tools facilitating the evaluation of DNELs and OELs from other sources in cases where the applicable Swedish OEL is lacking. Int J Occup Med Environ Health. 2020;33(5):611-20.


Asunto(s)
Industria Química/normas , Sustancias Peligrosas/efectos adversos , Exposición por Inhalación/prevención & control , Exposición por Inhalación/normas , Exposición Profesional/efectos adversos , Exposición Profesional/prevención & control , Exposición Profesional/normas , Adulto , Unión Europea , Femenino , Guías como Asunto , Humanos , Exposición por Inhalación/estadística & datos numéricos , Masculino , Concentración Máxima Admisible , Persona de Mediana Edad , Exposición Profesional/estadística & datos numéricos , Medición de Riesgo/métodos , Medición de Riesgo/estadística & datos numéricos , Encuestas y Cuestionarios , Suecia , Valores Limites del Umbral , Lugar de Trabajo
3.
Acta biol. colomb ; 24(2): 232-242, May-ago. 2019. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1010853

RESUMEN

RESUMEN En 2013 el pescado proporcionó a más de 3100 millones de personas casi el 20 % de la ingesta promedio de proteínas de origen animal per cápita (FAO, 2016). De acuerdo con el Programa de las Naciones Unidas para el Desarrollo (PNUD), en Colombia y, particularmente en las poblaciones ribereñas y costeras, el 90 % del consumo de proteína de origen animal proviene del pescado, como resultado de un acceso muy bajo a otro tipo de proteínas. Colombia enfrenta uno de los mayores problemas por contaminación ambiental a nivel mundial, generado en gran parte por el abuso de sustancias químicas para el aprovechamiento de minerales, mala disposición de aguas servidas y prácticas industriales y agrícolas inadecuadas, en cuerpos de aguas fundamentales para la dinámica poblacional de animales, vegetales y humanos. Como estrategia mundial para reducir los riesgos a la salud humana por consumo de pescado contaminado con metales pesados, se han considerado límites máximos permisibles, propuestos por diferentes entidades; sin embargo, el 31,5 % de los resultados de estudios publicados para Colombia, son superiores al límite permisible recomendado por la OMS (0,5 μg/g). Los resultados presentados en esta revisión evidencian la urgente necesidad de realizar estudios que evalúen el riesgo a la salud que enfrentan pobladores de zonas mineras y no mineras de Colombia, aportará también fundamentos científicos y bases para el establecimiento de ejes estratégicos que permitan la puesta en marcha de nuevos proyectos productivos que ofrezcan el acceso de la población a diversas fuentes de alimentación.


ABSTRACT In 2013, fish provided to more of 3100 million people about 20 % of the average intake of animal protein per capita (FAO, 2016). According to the United Nations Development Program (UNDP), in Colombia and, particularly in the coastal populations, 90 % of the protein consumption of animal origin comes from fish, mainly as a result of very low access comparing it with another type of proteins. Colombia faces one of the biggest problems due to global environmental pollution, generated in largely part by the abuse of chemical substances for the exploitation of minerals, poor disposal of wastewater and inadequate industrial and agricultural practices, in bodies of natural water essential for population dynamics of animals, plants and humans. As a global strategy to reduce the risks to human health from the consumption of fish contaminated with heavy metals, maximum permissible limits have been considered, proposed by different entities. However, 31.5 % of the results of studies published for Colombia, register higher than the permissible limit recommended by the WHO (0.5 μg/g). The results presented in this review, evidence the urgent need to conduct studies that assess the health risk faced by residents of mining and non-mining areas of Colombia, will also provide scientific foundations and bases for the establishment of strategic axes that permit the start-up of new productive projects, which offer the population access to various sources of food.

4.
Hig. aliment ; 32(286/287): 61-64, dez. 2018. tab
Artículo en Portugués | LILACS, VETINDEX | ID: biblio-1481871

RESUMEN

Aflatoxicose é uma intoxicação resultante da ingestão de aflatoxinas presentes nos alimentos. O quadro clínico está diretamente relacionado ao grau de contaminação do produto, tempo e quantidade ingerida pelo individuo assim como seu estado nutricional. O presente estudo teve como objetivo analisar a presença de aflatoxina em amostras selecionadas de pastas de amendoim comercializadas em Belo Horizonte, MG e correlacionar com a legislação vigente no Brasil e em outros países. Para tal, foram coletadas uma amostra de cada marca diferente de pasta de amendoim integral, sem adição de outros ingredientes, comercializadas no Mercado Central, em Belo Horizonte-MG, em dezembro de 2016. Como critério de escolha foram selecionadas todas as marcas comercializadas no referido estabelecimento, com a descrição de pasta de amendoim integral sem adição de açúcar e outros ingredientes. Os resultados mostraram que em todas as amostras analisadas a quantidade de aflatoxina encontrada foi menor que 2,0 µg/kg de amostra, dentro do recomendado na legislação brasileira e internacional.


Aflatoxicosis is an intoxication caused by the ingestion of aflatoxins present in food. The symptoms are directly related to the degree of contamination of the product, time and amount of ingest by the individual as well as their nutritional status. The present study aimed to determine the presence of aflatoxin in peanut pastes commercialized in Belo Horizonte, MG and correlate with current legislation in Brazil and other countries. For this purpose, six samples of whole peanut paste, without addition of other ingredients, commercialized at the Central Market in Belo Horizonte, MG, in December 2016. As a selection criterion, all the brands marketed in the establishment were selected. Description of whole peanut paste without added sugar and other ingredients. The results showed that in all analyzed samples the amount of aflatoxin found was lower than 2.0 µg / kg of sample, within the recommended in international and Brazilian legislation.


Asunto(s)
Aflatoxinas/análisis , Aflatoxinas/normas , Alimentos de Cacahuete , Límite Permisible de Riesgos Laborales , Micotoxinas
5.
NOVA publ. cient ; 14(25): 47-56, 2016. ilus, tab
Artículo en Español | LILACS, COLNAL | ID: biblio-955155

RESUMEN

Objetivo. Determinar prevalência de hipoacusia neurosensorial inducida por ruido en los trabajadores expuestos a ruido en cuatro empresas dedicadas al procesamiento de madera en la ciudad de Cartagena. Métodos. Sé realizó un estudio descriptivo de corte transversal en cuatro empresas de aserríos del sector madera de la ciudad de Cartagena, dedicadas a la transformación de la troza de madera en tablas y listones a través de operaciones de corte, cepillado y canteado de la madera. La población objeto de estudio fue de veinte trabajadores del área de maquinado expuestos a ruido. Se hizo una evaluación preliminar para conocer en forma detallada el ambiente de trabajo y las circunstancias bajo las cuales se exponen los trabajadores al ruido, las características del ruido y sus fuentes. Resultados. La prevalencia de hipoacusia neurosensorial inducida por ruido fue del 20%. Se encontró en el grupo objeto de estudio un 5 % con hipoacusia entre trabajadores de 41 a 45 años de edad y un 15% en trabajadores de más de 46 años de edad. En cuanto al tiempo de servicio en las distintas empresas, los trabajadores de 1 a 30 años presentaron el 20% de hipoacusia neurosensorial inducida por el ruido. En la medición de la exposición al ruido basada por puesto de trabajo en las distintas empresas seleccionadas se determinó el nivel continuo equivalente que oscila entre 95,7 dB(A) a 101,9 dB(A) el cual sobrepasa los valores límites permisibles de acuerdo a los criterios de ACGIH de USA. El nivel de riesgo es alto en una de las empresas mientras se encontró un nivel de riesgo medio en las otras empresas seleccionadas


Objective. To find out prevalence of noise-induced sensorineural hearing loss in workers exposed to noise in four companies implicated in wood processing in the city of Cartagena. Method. A descriptive cross-sectional study was conducted in four companies sawmills the timber sector of the city of Cartagena, dedicated to the transformation of the log wooden board and batten through cutting, brushing and chamfering wood. The study population was twenty machining area workers exposed to noise. A preliminary evaluation was done to know in detail the work environment and the circumstances under which workers are exposed to noise, noise characteristics and sources. Results. The prevalence of noise-induced sensorineural hearing loss was 20%. It was found in the study group that 5% with hearing loss among workers 41 to 45 years old and 15% in workers over 46 years old. As for the time of service in the various companies, workers from 1 to 30 years had 20% of sensorineural hearing loss induced by noise. In the measurement of noise exposure per job based on the different selected companies the equivalent continuous level of between 95.7 dB (A) to 101.9 dB (A) which exceeds the permissible limit values determined according to the US ACGIH criteria. The risk level is high in one of the companies as a medium risk was found in the other selected companies


Asunto(s)
Humanos , Pérdida Auditiva , Salud Laboral , Sordera , Pérdida Auditiva Sensorineural
6.
Anal Chem ; 86(8): 3712-6, 2014 Apr 15.
Artículo en Inglés | MEDLINE | ID: mdl-24654958

RESUMEN

We have demonstrated a novel sensing strategy employing a giant magnetoresistance (GMR) biosensor and DNA chemistry for the detection of mercuric ion (Hg(2+)). This assay takes advantages of high sensitivity and real-time signal readout of GMR biosensor and high selectivity of thymine-thymine (T-T) pair for Hg(2+). The assay has a detection limit of 10 nM in both buffer and natural water, which is the maximum mercury level in drinking water regulated by U.S. Environmental Protection Agency (EPA). The magnitude of the dynamic range for Hg(2+) detection is up to three orders (10 nM to 10 µM). Herein, GMR sensing technology is first introduced into a pollutant monitoring area. It can be foreseen that the GMR biosensor could become a robust contender in the areas of environmental monitoring and food safety testing.


Asunto(s)
Técnicas Biosensibles/métodos , Compuestos de Mercurio/análisis , Contaminantes Químicos del Agua/análisis , Emparejamiento Base , Biotina/química , ADN/química , Agua Potable/análisis , Inocuidad de los Alimentos , Dispositivos Laboratorio en un Chip , Límite de Detección , Campos Magnéticos , Concentración Máxima Admisible , Estreptavidina/química , Timina/química , Abastecimiento de Agua/análisis
7.
Med Pr ; 63(3): 329-44, 2012.
Artículo en Polaco | MEDLINE | ID: mdl-22880454

RESUMEN

BACKGROUND: High-frequency (HF) welders are the most common devices that make use of dielectric heating. They are a source of high-intensity electromagnetic fields (EMFs). Manual operation of those welders makes that the limbs are exposed to EMFs of extremely high intensity, far in excess of the currently admissible values. The aim of this study was to update knowledge of actual exposure of HF welder operators to EMF and to optimize the procedure of exposure assessment. MATERIAL AND METHODS: Measurements of the EMF intensity in the vicinity of 10 dielectric welders at work posts of 12 operators were performed. EMF measurements were made using the reference method, extended by auxiliary measurement points to measure induced currents I(L) in the limbs. Induced current measurements were performed in 20 operators tending the same HF welder. RESULTS: the highest values of the electric (E) and magnetic (H) fields measured at work posts were for whole body: E, up to 350 V/m, and H, up to 1.00 A/m; and for limbs: E, up to 600 V/m and H, up to 3.30 A/m. The W exposure indicator in the primary vertical measurement points was almost as high as 60. I(L) values measured at the wrist exceeded 64 mA and were individual-operator-dependent. CONCLUSIONS: EMF exposure of 25% of HF welder operators exceeded the national admissible values and after taking into account the operators' hands, this figure rose to 50%. The measured value of I(L), representing a measure of internal exposure to EMF, should serve as the main criterion in deciding whether working conditions are admissible.


Asunto(s)
Campos Electromagnéticos , Monitoreo del Ambiente/métodos , Exposición Profesional/análisis , Soldadura , Mano/efectos de la radiación , Cabeza/efectos de la radiación , Humanos , Concentración Máxima Admisible , Exposición Profesional/normas , Dosis de Radiación , Valores Limites del Umbral , Torso/efectos de la radiación
8.
Food Chem Toxicol ; 48(11): 3167-70, 2010 Nov.
Artículo en Inglés | MEDLINE | ID: mdl-20728500

RESUMEN

Hg, Pb and Cd levels in fresh and canned tuna were determined and assessed by comparing element levels in these samples with maximum permissible limits set by European legislation. The estimated weekly intakes by human consuming both fresh and canned tuna were also evaluated for possible consumer health risks. Among tested metals, Hg had the highest concentrations, followed by Pb and Cd either in fresh tuna or canned tuna. None of the tested samples surpassed the European regulatory limits fixed for Cd and Pb, whereas 8.9% of the tuna cans and 20% of fresh tuna samples exceeded standard for Hg. The size of tuna was a determining factor of Hg burden. A high intake of Hg surpassing the toxicological reference value established by WHO, was associated with consumption of larger size tuna specimens. Also canned tuna consumption with Hg concentrations higher than 1 µg kg(-1), strongly increased the consumer exposure. In contrast, Cd and Pb weekly intakes through consumption either of fresh tuna or canned tuna did not exceed the toxicological reference values established by WHO, and consequently there was no human health risk. A continuous surveillance system of Hg content in these fishery products is crucial for consumer protection.


Asunto(s)
Seguridad de Productos para el Consumidor , Contaminación de Alimentos/análisis , Conservación de Alimentos , Metales Pesados/análisis , Alimentos Marinos/análisis , Atún , Animales , Cadmio/análisis , Monitoreo del Ambiente/métodos , Humanos , Italia , Plomo/análisis , Límite de Detección , Concentración Máxima Admisible , Mercurio/análisis , Espectrofotometría Atómica
9.
Int J Occup Environ Health ; 16(3): 249-62, 2010.
Artículo en Inglés | MEDLINE | ID: mdl-20662417

RESUMEN

It has previously been shown that occupational exposure limits (OELs) for the same substance can vary significantly between different standard-setters. The work presented in this paper identifies the steps in the process towards establishing an OEL and how variations in those processes could account for these differences. This study selects for further scrutiny substances for which the level of OELs vary by a factor of 100, focussing on 45 documents concerning 14 substances from eight standard-setters. Several of the OELs studied were more than 20 years old and based on outdated knowledge. Furthermore, different standard-setters sometimes based their OELs on different sets of data, and data availability alone could not explain all differences in the selection of data sets used by standard-setters. While the interpretation of key studies did not differ significantly in standard-setters' documentations, the evaluations of the key studies' quality did. Also, differences concerning the critical effect coincided with differences in the level of OELs for half of the substances.


Asunto(s)
Concentración Máxima Admisible , Gestión de Riesgos/normas , Valores Limites del Umbral , Pruebas de Carcinogenicidad/normas , Europa (Continente) , Humanos , Gestión de Riesgos/organización & administración , Estados Unidos , United States Occupational Safety and Health Administration
10.
Ber Wiss ; 33(4): 419-35, 2010 Dec.
Artículo en Alemán | MEDLINE | ID: mdl-21469298

RESUMEN

The paper tackles the changes that occurred in the political culture and the episteme of risk in the Federal Republic of Germany in the 1970s. The objects of observation are limit values for hazardous industrial materials, especially for carcinogens. At the forefront of the production of such values in Germany was the German Research Society's Senate Commission for the Examination of Hazardous Industrial Materials. Limit values bring economy, politics, and science together and they mediate different interests. This makes limit values an ideal object of study to bring together changes in different parts of society. In 1972, a new category of limit values for carcinogenic substances is introduced, the so called "Technische Richtkonzentration" (TRK). This category of values does not assume that complete safety can be reached, as do limit values for hazardous industrial materials, so called "Maximale Arbeitsplatzkonzentrationen" (MAK). This means an important rupture in toxicological thinking. Until the 1970s, Paracelsus' dictum about dosage and poison still served as starting point for toxicologists. The innovation of TRK marks an important rupture in the episteme of regulating dangerous matters. Whereas until the 1970s there existed, at least as an ideal, the myth of "no risk" or "zero tolerance" even in the case of carcinogens, since the beginning of the 1970s, certainty is no more guaranteed by epistemically, but by socially robust knowledge. This also means the return of the risk society at the beginning of the 1970s, whereby cancer at the workplace becomes--in the view of the regulatory bodies--out of a medical problem a socioeconomic illness. The paper argues that these changes are connected to a general feeling of disorientation.


Asunto(s)
Carcinógenos/historia , Concentración Máxima Admisible , Neoplasias/historia , Enfermedades Profesionales/historia , Exposición Profesional/historia , Política , Factores Socioeconómicos , Valores Limites del Umbral , Toxicología/historia , Alemania Occidental , Historia del Siglo XX , Humanos
11.
Int J Environ Res Public Health ; 5(2): 86-90, 2008 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-18678921

RESUMEN

We measured the quartz content of 20 bulk settled dust and 200 respirable dust samples in a cross-sectional dust exposure assessment that is part of an epidemiological study to ascertain the risk of nonmalignant respiratory diseases among Zambian copper miners. Dust samples were collected from the copper mines of Mopani Copper Mine plc (Mufulira and Nkana Mines). Analytical measurements employed NIOSH Method 0600 for gravimetric analysis of respirable dust and NIOSH Method 7500 for quartz analysis in bulk and respirable dust samples. The measured quartz content of respirable dust showed that 59% and 26% of Mufulira and Nkana Mine samples, respectively, were above the calculated U.S. Occupational Safety and Health Administration permissible exposure limit. The mean intensities of respirable dust exposure at Mufulira and Nkana were 0.992 mg/m3 (range 0-7.674) and 0.868 mg/m3 (range 0-6.944), respectively while the mean intensities of respirable quartz at Mufulira and Nkana were 0.143 mg/m3 (range 0-1.302) and 0.060 mg/m3 (range 0-0.317), respectively. These results indicate weak dust monitoring at these mines which may increase the risk of nonmalignant disease in many miners. Since Zambian mining regulations do not have crystalline silica exposure limits, these results accord with the recommendation that Zambian mining houses and the government establish crystalline silica analysis laboratory capacity and adopt dust mass concentration occupational exposure limits for more protective dust monitoring of workers.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Monitoreo del Ambiente , Exposición por Inhalación/análisis , Minería , Exposición Profesional/análisis , Dióxido de Silicio/análisis , Silicosis/epidemiología , Contaminantes Ocupacionales del Aire/toxicidad , Cobre , Estudios Transversales , Polvo/análisis , Monitoreo Epidemiológico , Humanos , Exposición por Inhalación/efectos adversos , Concentración Máxima Admisible , National Institute for Occupational Safety and Health, U.S. , Exposición Profesional/efectos adversos , Salud Laboral , Cuarzo/análisis , Medición de Riesgo , Dióxido de Silicio/toxicidad , Silicosis/etiología , Valores Limites del Umbral , Estados Unidos , Zambia
12.
Med Pr ; 59(2): 187-95, 2008.
Artículo en Polaco | MEDLINE | ID: mdl-18652144

RESUMEN

In 2007, a new maximum admissible concentration value of 88 mg/m3 was specified for dichloromethane (DCM) in the Polish list of admissible concentrations of harmful chemicals and dusts in the work environment atmosphere. The new value is four times higher than the former one (20 mg/m3), valid in Poland for 20 past years. At the same time, it was decided that the value of short term exposure limit (STEL) shall no longer be specified. Dichloromethane is a chemical which can be absorbed by routes other than respiratory, therefore, biological monitoring is required to ensure that the risk is not underestimated. Experimental data support the conclusion that volatile chloroorganic compounds, including dichloromethane, are excreted with urine in the unchanged form, and thus their absorption and exposure can be easily assessed. Concentration of dichloromethane in urine determined at the end of work shift is proposed in Poland as a specific index of dichloromethane exposure. Dichloromethane inhalation exposure at maximum admissible concentration of 88 mg/m3 corresponds with biological exposure index (BEI) of 0.15 mg DCM/l urine. The BEI value proposed in Poland for DCM is compatible with that specified by the American Conference of Governmental Industrial Hygienists (ACGIH).


Asunto(s)
Monitoreo del Ambiente/métodos , Exposición por Inhalación/análisis , Cloruro de Metileno/orina , Exposición Profesional/análisis , Plaguicidas/orina , Humanos , Concentración Máxima Admisible , Polonia , Factores de Riesgo , Valores Limites del Umbral
13.
Health Phys ; 85(2): 220-7, 2003 Aug.
Artículo en Inglés | MEDLINE | ID: mdl-12938970

RESUMEN

The new dose limits recently adopted in Canada (and elsewhere in the world) have made it more difficult to detect some radionuclides by in vivo counting at the average dose limit of 20 mSv. This is particularly true for natural uranium. Two techniques have been developed by the Human Monitoring Laboratory to reduce the Minimum Detectable Activity (MDA) for the lung counting of this nuclide. The first technique, developed in collaboration with Cameco, is to either sum sequential counts of an individual or to sum spectra of a group of workers similarly occupationally exposed. This technique offers a reduction in the MDA of up to a factor of three. The second technique, developed in collaboration with CNEN, involves the summing of photopeaks within an individual spectrum and offers a reduction in the MDA of up to a factor of two.


Asunto(s)
Contaminantes Atmosféricos/análisis , Contaminantes Atmosféricos/farmacocinética , Pulmón/metabolismo , Exposición Profesional/análisis , Radiometría/métodos , Uranio/análisis , Adulto , Carga Corporal (Radioterapia) , Canadá , Humanos , Masculino , Concentración Máxima Admisible , Persona de Mediana Edad , Modelos Biológicos , Control de Calidad , Dosis de Radiación , Radiometría/instrumentación , Reproducibilidad de los Resultados , Tamaño de la Muestra , Sensibilidad y Especificidad , Valores Limites del Umbral
14.
Rev. Soc. Esp. Enferm. Nefrol ; 4(4): 6-10, oct. 2001. tab
Artículo en Es | IBECS | ID: ibc-9637

RESUMEN

En alguna ocasión, todos nos hemos tenido que enfrentar con un catéter central que no funcionaba de forma correcta, concretamente debido a una disminución del flujo de salida que hacia completamente inútil la depuración. Sin entrar a analizar las causas que conducen a ello ( malposición, restos de fibrina, etc ... ), vamos a exponer el estudio que hemos realizado sobre la calidad de la técnica una vez adoptada la solución más fácil e inmediata, o sea, la inversión de las líneas, comparando para ello el valor de la recirculación de, la urea en condiciones normales, con el que se obtiene al invertir las líneas arterial y venosa. Hemos estudiado 46 pacientes, 18 varones y 28 mujeres, con edades comprendidas entre los 28 y los 82 años, todos ellos portadores de catéteres de doble luz normofuncionantes, fabricados de silicona, con luces paralelas, un diámetro 11,5 FR, longitudes de 15 ó 20 cm y situados en diversas localizaciones. Al invertir las luces del catéter nuestros resultados muestran que, pese a la evidencia de un aumento significativo en la tasa de recirculación de la urea al trocar las líneas respecto a las condiciones normales de uso, se logran unas cifras que la mayoría de los autores consideran aceptables. Igualmente, el incremento en la resistencia venosa, por otra parte esperado, se mantiene en límites permisibles. Por tanto, la inversión de luces durante la sesión permite mantener una diálisis adecuada con matices, ya que nos gustaría confirmar estos resultados utilizando el modelo cinético de la urea (AU)


Asunto(s)
Adulto , Anciano , Femenino , Masculino , Persona de Mediana Edad , Humanos , Cateterismo Urinario , Insuficiencia Renal Crónica/terapia , Diálisis Renal/instrumentación , Cateterismo Urinario/clasificación , Resultado del Tratamiento , Resistencia Vascular , Diálisis Renal/métodos
15.
Ingeniería sanitaria y ambiental (Buenos Aires) ; (37): 31-35, mar.-abr. 1998. Ilus, Tab
Artículo en Español | BINACIS | ID: bin-139084

RESUMEN

Analiza 30 muestras de agua, 20 de sedimentos y los organismos acuáticos del Lago San Roque, Argentina, encontrando una concentración de fósforo mayor a los límites permisibles internacionales. Concluye que este lago está eutroficado por la excesiva carga de fósforo y nitrógeno, el ingreso directo de las aguas residuales y el grado de desarrollo del fitoplancton


Asunto(s)
Lagos , Contaminación de Lagos y Embalses , Ambiente , Eutrofización , Fitoplancton
16.
Ing. sanit. ambient ; (37): 31-35, mar.-abr. 1998. ilus, tab
Artículo en Español | BINACIS | ID: biblio-1162724

RESUMEN

Analiza 30 muestras de agua, 20 de sedimentos y los organismos acuáticos del Lago San Roque, Argentina, encontrando una concentración de fósforo mayor a los límites permisibles internacionales. Concluye que este lago está eutroficado por la excesiva carga de fósforo y nitrógeno, el ingreso directo de las aguas residuales y el grado de desarrollo del fitoplancton


Asunto(s)
Eutrofización , Fitoplancton , Lagos , Ambiente , Contaminación de Lagos y Embalses
17.
Braz. j. med. biol. res ; 26(8): 875-7, Ago. 1993.
Artículo en Inglés | LILACS | ID: lil-148760

RESUMEN

A technique for the determination of the threshold concentrations of chemical substances for elicitation of spreading depression is described. The technique minimizes the interference of mechanical stimulating effects and alterations in the susceptibility of the retina to spreading depression due to changes in unstirred layers at the liquid-tissue interphase. The following threshold concentrations were shown to elicit the wave: 8000-10000 microM KCl, 100-200 microM sodium glutamate, 5-10 microM sodium kainate, 10-20 microM sodium N-methyl-aspartate, 600-1200 microM (NH4)2SO4 and 400-600 microM BaCl2. Variations of K+ or Mg2+ concentration in the standard Ringer solution that may cause an increase or decrease of spreading depression velocity have an inverse effect on the threshold for elicitation of the reaction


Asunto(s)
Animales , Depresión de Propagación Cortical , Retina/fisiología , Embrión de Pollo , Límite Permisible de Riesgos Laborales , Soluciones Isotónicas/administración & dosificación , Factores de Tiempo
18.
Salvador; s.n; 1993. 39 p. tab.
Tesis en Portugués | LILACS | ID: lil-137594

RESUMEN

Uma fundiçäo de chumbo, em funcionamento na cidade de Santo Amaro da Purificaçäo, BA, desde 1960, polui intensamente o ambiente com chumbo (Pb) e cádmio (Cd). Em 1991, realizou-se um estudo de prevalência de disfunsäo renal, em 344 indivíduos de ambos os sexos, com idade entre 20 e 50 anos, residentes em um raio de 500 m a partir da chaminé da fábrica. Numa área sem exposiçäo industrial foram estudados 81 indivíduos. Os indicadores de exposiçäo utilizados foram chumbo no sangue (PbS) e cádmio na urina (CdU). Disfunçäo renal foi investigada por N-acetil-ß-D-glucosaminidase (NAG), proteinúria, ácido úrico e creatinina séricos. Quanto aos indicadores de efeito, os resultados encontrados näo diferem significantemente nas duas áreas estudadas. Os indivíduos residentes em Santo amaro da Purificaçäo, com exposiçäo ambiental e ocupacional, mostraram médias de PbS e CdU superiores àqueles com exposiçäo apenas ambiental. Os indicadores de efeito näo mostram diferenças entre estes grupos


Asunto(s)
Humanos , Masculino , Femenino , Adulto , Persona de Mediana Edad , Cadmio/orina , Exposición Profesional/efectos adversos , Enfermedades Renales/inducido químicamente , Plomo/sangre , Límite Permisible de Riesgos Laborales , Brasil , Exposición a Riesgos Ambientales , Salud Laboral
19.
s.l; s.n; 1991. <236> p. ilus, tab.
Tesis en Portugués | LILACS | ID: lil-112931

RESUMEN

O trabalho em turnos interfere no ritmo das variaçöes circadianas, implicando na saúde e na produtividade dos trabalhadores e podem afetar a susceptibilidade tóxica. Questiona-se, se os níveis permitidos ou recomendados para os riscos químicos (limites de exposiçäo ocupacional, LEOs) devem ser ajustados para esses casos e sob qual parâmetro. Revisaram-se as evidências dessas variaçöes publicadas nos últimos 20 anos, listando 500 agentes químicos com importância ocupacional, divididos em 20 efeitos à saúde. Foram revistas as variaçöes nos eventos cinéticos e dinâmicos. Demonstrou-se que as evidências cobrem os 20 efeitos classificados e referem-se, em parte às observaçöes com efeitos näo letais. Constatou-se que as alteraçöes nos LEOs näo podem ser propostas exclusivamente com base na variaçäo dos eventos toxicocinéticos. Os eventos toxicodinâmicos, e outros fatores podem ser importantes e, na grande maioria, o próprio LEO näo tem sustentaçäo científica adequada. Recomenda-se que os indicadores de exposiçäo ou de efeito sejam estabelecidos como desvio de uma funçäo. Recomenda-se que a exposiçäo seja interrompida em determinados horários, específicos para cada substância, ao invés do emprego de um redutor algébrico.


Asunto(s)
Ritmo Circadiano/efectos de los fármacos , Exposición Profesional , /efectos adversos , Toxicología , Contaminantes Ocupacionales del Aire/efectos adversos , Susceptibilidad a Enfermedades , Enfermedades Profesionales/inducido químicamente , Concentración Máxima Admisible , Riesgos Laborales
20.
s.l; s.n; 1991. <236> p. ilus, tab.
Tesis en Portugués | HomeoIndex - Homeopatia | ID: hom-8121

RESUMEN

O trabalho em turnos interfere no ritmo das variações circadianas, implicando na saúde e na produtividade dos trabalhadores e podem afetar a susceptibilidade tóxica. Questiona-se, se os níveis permitidos ou recomendados para os riscos químicos (limites de exposição ocupacional, LEOs) devem ser ajustados para esses casos e sob qual parâmetro. Revisaram-se as evidências dessas variações publicadas nos últimos 20 anos, listando 500 agentes químicos com importância ocupacional, divididos em 20 efeitos à saúde. Foram revistas as variações nos eventos cinéticos e dinâmicos. Demonstrou-se que as evidências cobrem os 20 efeitos classificados e referem-se, em parte às observações com efeitos não letais. Constatou-se que as alterações nos LEOs não podem ser propostas exclusivamente com base na variação dos eventos toxicocinéticos. Os eventos toxicodinâmicos, e outros fatores podem ser importantes e, na grande maioria, o próprio LEO não tem sustentação científica adequada. Recomenda-se que os indicadores de exposição ou de efeito sejam estabelecidos como desvio de uma função. Recomenda-se que a exposição seja interrompida em determinados horários, específicos para cada substância, ao invés do emprego de um redutor algébrico.(AU)


Asunto(s)
Horario de Trabajo por Turnos/efectos adversos , Toxicología , Exposición Profesional , Ritmo Circadiano , Concentración Máxima Admisible , Riesgos Laborales , Contaminantes Ocupacionales del Aire/efectos adversos , Enfermedades Profesionales/inducido químicamente , Susceptibilidad a Enfermedades
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