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1.
Agora (Rio J.) ; 24(1): 91-99, Jan.-Apr. 2021.
Artículo en Portugués | LILACS, Index Psicología - Revistas | ID: biblio-1284999

RESUMEN

RESUMO: Este trabalho discute o fenômeno da exibição dos adolescentes nas redes sociais. Iniciamos interrogando o enfraquecimento do Outro parental e os impasses decorrentes dos avanços da virtualidade na contemporaneidade. Recuperamos o debate sobre o narcisismo na adolescência, apresentando o "dar-se a ver" e a "exibição" como mecanismos distintos em relação ao olhar do Outro da cultura. Seguindo as proposições de Lacan sobre o instante de ver e a esquize do olho e do olhar, concluímos que o visualizar é uma operação dominante no ato de exibição, levando os jovens à repetição e não à estabilização no campo do Outro.


Abstract: This paper discusses the phenomenon of adolescent exhibition in social media. We started by questioning the weakening of the parental Other and the impasses arising from the advances of virtuality in contemporary times. We rescue the debate about narcissism in adolescence, presenting the "offer of oneself to the gaze" and the "exhibition" as distinct mechanisms in relation to the Other's look in the culture. According to Lacan's propositions about the moment of seeing, as well as the eye and gaze's "schize", the research concludes that viewing is a dominant operation within the act of exhibiting, which leads to repetition and not stabilization of adolescents in the field of the Other.


Asunto(s)
Psicoanálisis , Conducta del Adolescente , Trastorno de Adicción a Internet , Límites Permisibles , Redes Sociales en Línea
2.
Terminología | DeCS - Descriptores en Ciencias de la Salud | ID: 051897

RESUMEN

3.
Entramado ; 16(2): 298-310, jul.-dic. 2020. tab, graf
Artículo en Inglés | LILACS-Express | LILACS | ID: biblio-1149283

RESUMEN

ABSTRACT Cocoa (Theobroma cacao L.) is a species originating from the humid tropics. Over 70,000 km2 worldwide is dedicated to growing cocoa, and approximately 30% of its global production is concentrated in the equatorial regions of Central and South America, the Antilles and tropical Asia. The demand for cocoa is growing significantly but the presence of cadmium (Cd) in the species is a potential problem limiting its commercialization. The present study determined the Cd, Ni, Pb and Cr content in two cocoa-producing regions in northern Colombia. Foliage (leaf, bean and shell) and soil were analyzed. The mean Ni, Pb and Cr content in the plant tissue did not exceed the maximum permissible limits set by the United States Environmental Protection Agency (EPA). The mean Cd content in the beans was 0.51 mg kg-1 in region 1 and 0.66 mg kg-1 in region 2, which are considered risky per reports from the European Union and restrict the product's export. These results serve as a reference for future research on cocoa.


RESUMEN El cacao (Theobroma cacao L.) es una especie originaria de los trópicos húmedos. Más de 70,000 km2 en todo el mundo están dedicados a su cultivo y aproximadamente el 30% de su producción mundial se concentra en las regiones ecuatoriales de América Central y del Sur las Antillas y Asia tropical. La demanda de cacao está creciendo significativamente, pero la presencia de cadmio (Cd) en la especie es un problema potencial que limita su comercialización. El presente estudio determinó el contenido de Cd, Ni, Pb y Cr en dos regiones productoras de cacao en el norte de Colombia. Se analizaron el tejido (hoja, frijol y cáscara) y el suelo. El contenido medio de Ni, Pb y Cr en el tejido vegetal no excedió los límites máximos permisibles establecidos por la Agencia de Protección Ambiental (EPA) de los Estados Unidos. El contenido medio de Cd en los frijoles fue de 0,51 mg kg-1 en la región 1 y 0,66 mg kg-1 en la región 2, que se consideran riesgosos según los informes de la Unión Europea y restringen la exportación del producto. Estos resultados sirven como referencia para futuras investigaciones sobre el cacao.


RESUMO O cacau (Theobroma cacao L) é uma espécie originária dos trópicos úmidos. Mais de 70.000 km2 em todo o mundo são dedicados à sua cultura e aproximadamente 30% de sua produção global está concentrada nas regiões equatoriais da América Central e do Sul, Antilhas e Ásia tropical. A demanda por cacau está crescendo significativamente, mais a presença de cádmio (Cd) nas espécies é um problema potencial que limita sua comercialização. O presente estudo determinou o teor de Cd, Ni, Pb e Cr em duas regiões produtoras de cacau no norte da Colômbia. A folhagem (folha, feijão e casca) e o solo foram analisados. O teor médio de Ni, Pb e Cr no tecido vegetal não excedeu os límites máximos permitidos estabelecidos pela Agência de Proteção Ambiental dos Estados Unidos (EPA). O conteúdo médio de Cd nos grãos foi de 0,51 mg kg-1 na região 1 e 0,66 mg kg-1 na região 2, que são considerados de risco por relatórios da União Europeia e restringem a exportação do produto. Esses resultados servem como referência para futuras pesquisas sobre cacau.

4.
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
5.
Toxicol Lett ; 334: 117-144, 2020 Nov 01.
Artículo en Inglés | MEDLINE | ID: mdl-32497562

RESUMEN

This paper derives an occupational exposure limit for benzene using quality assessed data. Seventy-seven genotoxicity and 36 haematotoxicity studies in workers were scored for study quality with an adapted tool based on that of Vlaanderen et al., 2008 (Environ Health. Perspect. 116 1700-5). These endpoints were selected as they are the most sensitive and relevant to the proposed mode of action (MOA) and protecting against these will protect against benzene carcinogenicity. Lowest and No- Adverse Effect Concentrations (LOAECs and NOAECs) were derived from the highest quality studies (i.e. those ranked in the top tertile or top half) and further assessed as being "more certain" or "less certain". Several sensitivity analyses were conducted to assess whether alternative "high quality" constructs affected conclusions. The lowest haematotoxicity LOAECs showed effects near 2 ppm (8 h TWA), and no effects at 0.59 ppm. For genotoxicity, studies also showed effects near 2 ppm and showed no effects at about 0.69 ppm. Several sensitivity analyses supported these observations. These data define a benzene LOAEC of 2 ppm (8 h TWA) and a NOAEC of 0.5 ppm (8 h TWA). Allowing for possible subclinical effects in bone marrow not apparent in studies of peripheral blood endpoints, an OEL of 0.25 ppm (8 h TWA) is proposed.


Asunto(s)
Contaminantes Ocupacionales del Aire/toxicidad , Benceno/toxicidad , Mutágenos/toxicidad , Exposición Profesional/análisis , Estudios Epidemiológicos , Humanos , Concentración Máxima Admisible , Nivel sin Efectos Adversos Observados , Exposición Profesional/efectos adversos , Medición de Riesgo , Valores Limites del Umbral
6.
Toxins (Basel) ; 12(3)2020 03 19.
Artículo en Inglés | MEDLINE | ID: mdl-32204439

RESUMEN

A survey on 120 cereal samples (barley, maize, rice and wheat) from Algerian markets has been carried out to evaluate the presence of 15 mycotoxins (ochratoxin A, deoxynivalenol, fumonisin B1 and B2, T-2 and HT-2 toxins, zearalenone, fusarenon X, citrinin, sterigmatocystin, enniatins A, A1, B and B1, and beauvericin). With this purpose, a QuEChERS-based extraction and ultra-high performance liquid chromatography coupled to tandem mass spectrometry (UHPLC-MS/MS) were used. Analytical results showed that 78 cereal samples (65%) were contaminated with at least one toxin, while 50% were contaminated with three to nine mycotoxins. T-2 toxin, citrinin, beauvericin and deoxynivalenol were the most commonly found mycotoxins (frequency of 50%, 41.6%, 40.8% and 33.3%, respectively). Fumonisins (B1 + B2), enniatins B and B1, deoxynivalenol and zearalenone registered high concentrations (289-48878 µg/kg, 1.2-5288 µg/kg, 15-4569 µg/kg, 48-2055 µg/kg and 10.4-579 µg/kg, respectively). Furthermore, concentrations higher than those allowed by the European Union (EU) were observed in 21, 8 and 1 samples for fumonisins, zearalenone and deoxinivalenol, respectively. As a conclusion, the high levels of fumonisins (B1 + B2) in maize and deoxynivalenol, zearalenone and HT-2 + T-2 toxins in wheat, represent a health risk for the average adult consumer in Algeria. These results pointed out the necessity of a consistent control and the definition of maximum allowed levels for mycotoxins in Algerian foodstuffs.


Asunto(s)
Exposición Dietética/análisis , Grano Comestible/química , Contaminación de Alimentos/análisis , Fumonisinas/análisis , Tricotecenos/análisis , Zearalenona/análisis , Argelia , Cromatografía Líquida de Alta Presión , Grano Comestible/normas , Humanos , Límite de Detección , Concentración Máxima Admisible , Reproducibilidad de los Resultados , Medición de Riesgo , Espectrometría de Masas en Tándem , Triticum/química , Zea mays/química
7.
Cult. cuid. enferm ; 17(1): 20-31, 2020.
Artículo en Español | LILACS, BDENF - Enfermería, COLNAL | ID: biblio-1247417

RESUMEN

La constante exposición a sustancias químicas en diferentes espacios donde se desarrolla la vida humana, hace necesario conocer la naturaleza de éstas, para determinar la forma más adecuada de manipularlas disminuyendo su riesgo. Tomar a la ligera su uso en el trabajo o en el hogar, puede ser el origen para un accidente o una enfermedad. Los componentes químicos tienen unas características propias para ser clasificados, sea por sus propiedades fisicoquímicas o por sus efectos negativos sobre la salud de las personas y el medio ambiente. Por lo tanto, es necesario comprender la toxicología de los productos peligrosos, su potencial de envenenar y dañar, además de reconocer las vías de penetración al organismo: nariz, boca, piel u ojos; para tomar acciones de control que eviten la presencia de estos agentes en nuestro entorno. El riesgo químico se presenta cuando una sustancia peligrosa está en concentraciones por encima de sus valores límites permisibles en cualquiera que sea su presentación en el ambiente (sólido, líquido, gaseoso), y al entrar en contacto con el individuo amenaza su integridad y/o su bienestar mediante efectos adversos agudos o crónicos. Este riesgo no sólo afecta a las personas, sino también a los ecosistemas por medio de la contaminación del suelo y de las aguas, y del deterioro de la capa de ozono. Como los productos químicos hacen parte importante del desarrollo del ser humano, tener herramientas de información necesaria para su empleo es de gran ayuda para la gestión alrededor del riesgo químico, y es ahí donde el Sistema Globalmente Armonizado de Clasificación y Etiquetado de Sustancias Química se convierte es un aliado de la industria y la comercialización de estos productos, ofreciendo una serie de elementos de comunicación de peligros para mayor seguridad en el manejo, almacenamiento y transporte de sustancias peligrosas y prevención de la enfermedad.


The constant exposure to chemical substances in different spaces where human life develops, makes it necessary to know their nature, to determine the most appropriate way to handle them, reducing their risk. Take lightly its use at work or at home, It may be the source for an accident or illness. The chemical components have their own charac-teristics to be classified, either because of their physicochemical properties or because of their negative effects on people's health and the environment. Therefore, it is necessary to understand the toxicology of dangerous products, their potential to poison and damage, in addition to recognizing the penetration pathways to the organism: nose, mouth, skin or eyes; to take control actions that prevent the presence of these agents in our environ-ment. The chemical risk arises when a hazardous substance is in concentrations above its permissible limit values in whatever its presentation in the environment (solid, liquid, gas), and upon contact with the individual threatens its integrity and / or your well-be-ing through acute or chronic adverse effects. This risk not only affects people, but also ecosystems through soil and water pollution, and the deterioration of the ozone layer. As chemical products are an important part of the development of human beings, having the necessary information tools for their use is of great help for the management around chemical risk, and that is where the Globally Harmonized System of Classification and Labeling of Chemical Substances becomes It is an ally of the industry and the commer-cialization of these products, offering a series of danger communication elements for greater safety in the handling, storage and transport of dangerous substances and disease prevention.


Asunto(s)
Salud
8.
Aerosp Med Hum Perform ; 90(9): 807-812, 2019 Sep 01.
Artículo en Inglés | MEDLINE | ID: mdl-31426897

RESUMEN

INTRODUCTION: The previous Spacecraft Maximal Allowable Concentrations (SMACs) for methanol were established by characterizing minor effects upon cognitive functions as a no-observable adverse effects level (NOAEL). However, an increasing awareness of the risk posed by Space-Associated Neuro-ocular Syndrome (SANS) has caused NASA Toxicology to reexamine SMACs for methanol because exposure to it can also adversely affect ocular health. An updated review of the literature indicates that no adjustments to the SMACs due to SANS complications were required, while confirming that effects upon the central nervous system remain the appropriate basis for the SMACs for methanol. Our review, however, identified several issues that provide justification for modest SMAC reductions. It has recently been recognized that inhaled methanol may reach the brain via the olfactory system and be absorbed there into the highly toxic metabolite formaldehyde. A benchmark dose (BMD) for an extra risk of 10%, derived from an analysis of the incidences of neurological lesions in monkeys chronically exposed to methanol, is an order of magnitude less than the Environmental Protection Agency's (EPA's) reference concentration for chronic inhalation of methanol. Reports calling attention to the relative insensitivity of traditional methods of assessing cognitive function erode confidence that adverse effects at the concentration reported as a NOAEL would have been recognizable. Therefore, an additional modest safety factor of three is applied to SMACs for methanol.Scully RR, Garcia H, McCoy JT, Ryder VE. Revisions to limits for methanol in the air of spacecraft. Aerosp Med Hum Perform. 2019; 90(9):807-812.


Asunto(s)
Cognición/efectos de los fármacos , Metanol/toxicidad , Síndromes de Neurotoxicidad/prevención & control , Nave Espacial/normas , Valores Limites del Umbral , Animales , Astronautas , Modelos Animales de Enfermedad , Haplorrinos , Humanos , Incidencia , Concentración Máxima Admisible , Síndromes de Neurotoxicidad/epidemiología , Síndromes de Neurotoxicidad/etiología , Nivel sin Efectos Adversos Observados , Exposición Profesional/normas , Pruebas de Toxicidad Crónica
9.
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.

10.
CES med ; 33(2): 100-110, mayo-ago. 2019. tab, graf
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1055536

RESUMEN

Resumen Introducción: la exposición dietaria a la aflatoxina es un factor de riesgo para carcinoma hepatocelular, el cáncer primario de hígado más frecuente. Esta asociación se estableció gracias a la evidencia in vitro e in vivo de la relación entre la exposición a la aflatoxina B1 y la transversión G→T en el codón 249 del gen TP53, así como evidencia de la sinergia entre la aflatoxina y la infección crónica por virus de la hepatitis B. Métodos: se determinó la frecuencia de la mutación R249S del gen TP53 en 30 pacientes con diagnóstico de cirrosis y/o carcinoma hepatocelular quienes fueron sometidos a trasplante hepático en un hospital en Medellín, Colombia. Se extrajo ADN a partir de las muestras de explante hepático, se amplificó el fragmento de interés y se detectó la mutación por polimorfismos de longitud de fragmentos de restricción. Resultados: se encontró la mutación R249S en una de las 30 muestras analizadas (3,33 %) y se determinó, por medio de marcadores serológicos, infección por el virus de la hepatitis B en dos casos (6,67 %). No se encontró simultáneamente la mutación y la presencia de los marcadores de infección por virus de la hepatitis B. Conclusión: los resultados sugieren una baja exposición dietaria con aflatoxina B1 en la población de estudio. Sin embargo, es importante tener en cuenta la regulación de los límites permisibles de aflatoxina B1 y la inclusión en el diagnóstico diferencial de carcinoma hepatocelular, dada la heterogeneidad de las condiciones de la población en diferentes regiones del país.


Abstract Introduction: The dietary exposure to aflatoxin is a risk factor of hepatocellular carcinoma, the most frequent primary liver cancer. This risk factor was identified after in vivo and in vitro evidence of the relation between exposure to aflatoxin B1 and transversion G → T at 249 codon of the TP53 gene; as well as evidence of the synergy between hepatitis B virus chronic infection. Methods: the frequency of the R249S mutation of the TP53 gene was determined in 30 cases of cirrhosis and/or hepatocellular carcinoma, with liver transplantation in the hepatology unit of a hospital in Medellín, Colombia. DNA was extracted from the liver explant samples; the sequence of interest was amplified, and the mutation was detected by restriction fragment length polymorphisms. Results: the R249S mutation was found in 1 of the 30 samples analyzed (3.33 %); and hepatitis B virus infection was detected by serological markers in 2 of the 30 cases (6.67 %). We did not find the mutation and the presence of hepatitis B virus infection markers at the same time in any of the samples. Conclusion: The results suggest a low dietary exposure with aflatoxin B1 in the study population. However, it is important to take into consideration the regulation of the permissible limits of aflatoxin B1 and the inclusion in the differential diagnosis of hepatocellular carcinoma, given the heterogeneity of the conditions of the population in different regions of the country.

11.
Arch Toxicol ; 93(5): 1187-1200, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30993379

RESUMEN

Derived no-effect levels for workers (wDNELs) under the European REACH legislation have many aspects in common with occupational exposure limits (OELs). In an attempt to examine under which circumstances wDNELs might be used as exposure guidance outside their intended application, we compared derivation methods, coverage of substances and numerical values of wDNELs against two regulatory OEL lists (European Commission and Sweden) and three sets of recommendations (European SCOEL, German MAK and US ACGIH). Finally, we looked closer at wDNELs where SCOEL concluded that data were insufficient to derive an OEL. Major differences between wDNELs and OELs include regulatory background, intended use, actors involved, substance selection criteria, transparency and procedure of derivation, and operationalisation in terms of risk management measures. As of summer 2018, approximately five times more substances were covered by wDNELs than by the five sets of OELs examined herein. Meanwhile, many occupationally relevant pollutants were not covered by wDNELs, e.g. one-third of Swedish OELs lack corresponding wDNELs. We also note that wDNELs and OELs for the same substance may vary considerably, up to several orders of magnitude. In conclusion, with extensive substance coverage, wDNELs extend the landscape beyond the OELs. That said, important limitations are (1) that many air pollutants relevant for workers' health are not covered by REACH, and (2) concerns for inconsistencies in the derivation of wDNELs and in their level of protection. In particular, that route-to-route extrapolation is a common practice that may be grossly misleading when the effect of concern is local, e.g. sensitisation.


Asunto(s)
Exposición Profesional/legislación & jurisprudencia , Salud Laboral/legislación & jurisprudencia , Gestión de Riesgos/legislación & jurisprudencia , Unión Europea , Humanos , Concentración Máxima Admisible , Nivel sin Efectos Adversos Observados , Valores Limites del Umbral
12.
J Appl Toxicol ; 39(5): 688-701, 2019 05.
Artículo en Inglés | MEDLINE | ID: mdl-30620996

RESUMEN

Occupational exposure limits (OELs) have been previously proposed for diacetyl; however, most of these values are based on worker cohort studies that are known to have several limitations and confounders. In this analysis, an 8 hour time-weighted average (TWA) OEL for diacetyl was derived based on data from a chronic, 2 year animal inhalation study recently released by the US National Toxicology Program. In that study, complete histopathology was conducted on male and female mice and rats exposed to 0, 12.5, 25 or 50 ppm diacetyl. Several responses in the lower respiratory tract of rats (the more sensitive species) were chosen as the critical endpoints of interest. Benchmark concentration (BMC) modeling of these endpoints was used to estimate BMC values associated with a 10% extra risk (BMC10 ) and the associated 95% lower confidence bound (BMCL10 ), which were subsequently converted to human equivalent concentrations (HECs) using a computational fluid dynamics-physiologically based pharmacokinetic (CFD-PBPK) model to account for interspecies dosimetry differences. A composite uncertainty factor of 8.0 was applied to the human equivalent concentration values to yield 8 hour TWA OEL values with a range of 0.16-0.70 ppm. The recommended 8 hour TWA OEL for diacetyl vapor of 0.2 ppm, based on minimal severity of bronchiolar epithelial hyperplasia in the rat, is practical and health-protective.


Asunto(s)
Contaminantes Ocupacionales del Aire/análisis , Diacetil/análisis , Exposición por Inhalación/normas , Modelos Biológicos , Exposición Profesional/normas , Contaminantes Ocupacionales del Aire/farmacocinética , Animales , Diacetil/farmacocinética , Relación Dosis-Respuesta a Droga , Humanos , Exposición por Inhalación/análisis , Concentración Máxima Admisible , Exposición Profesional/análisis , Ratas , Medición de Riesgo , Especificidad de la Especie , Valores Limites del Umbral
13.
Food Addit Contam Part B Surveill ; 12(1): 65-73, 2019 Mar.
Artículo en Inglés | MEDLINE | ID: mdl-30488777

RESUMEN

A total of 158 fruit and vegetable samples produced in Jordan were examined for the presence of pesticide residues using the multi-residue analysis technique by Liquid Chromatography-tandem Mass Spectrometry (LC-MS/MS) and the QuEchERS extraction method. A total of 73 samples (46%) were free from detectable residues, while 85 samples (54%) contained residues. Among the tested samples, 34 (22%) contained residues above Maximum Residue Levels (MRLs) and 51 (32%) contained residues at or below MRLs. Most of the detected residues were found in sweet pepper, peach and apricot samples. Only watermelon samples were free from detectable residues, while tomato and melon samples exhibited residues below MRLs. Out of the 113 pesticides tested, 22 pesticides were found above the limit of detection, 9 of which (hexaconazole, propargite, propiconazole, myclobutanil, thiamethoxam, thiacloprid, clothianidin, clofentezine and pyridaben) had residues that violate MRLs according to European regulations. A continuous monitoring programme for pesticide residues in Jordanian fruits and vegetables is highly recommended.


Asunto(s)
Cromatografía Líquida de Alta Presión/métodos , Contaminación de Alimentos/análisis , Frutas/química , Residuos de Plaguicidas/análisis , Espectrometría de Masas en Tándem/métodos , Verduras/química , Jordania , Límite de Detección , Concentración Máxima Admisible , Plaguicidas/análisis , Reproducibilidad de los Resultados
14.
Rev. peru. med. integr ; 4(1): 4-14, 2019. tab
Artículo en Español | LILACS, MOSAICO - Salud integrativa | ID: biblio-1145755

RESUMEN

Objetivos. Determinar la composición química, características físico-químicas y el efecto genotóxico del aceite de Plukenetia volubilis L. Materiales y métodos. Se evaluó el perfil de ácidos grasos, tocoferoles, esteroles, fosfolípidos, carotenoides, tocotrienoles y fenoles; así como las características físico-químicas y trazas metálicas. La genotoxicidad fue evaluada a través del ensayo de morfología de la cabeza de espermatozoides. Para este ensayo, se emplearon ratones albinos machos formando 3 grupos de experimentación de 7 animales cada uno: control negativo (solución salina 0,9%), control positivo (50 mg/kg/pc/día de ciclofosfamida) y grupo problema que recibió por vía oral 0,5 ml de aceite sacha inchi (NIMET); las sustancias se administraron cada 24 horas por 5 días. Resultados. El aceite contiene ácidos grasos poliinsaturados(81,72%), monoinsaturados (10,31%) y saturados(7,67%); siendo el alfa-linolénico (47,35%) y el linoleico (34,34%) los más abundantes. El tocoferol y esterol más abundante fueron el gamma-tocoferol y el beta-siitosterol respectivamente, y en escasa cantidad se halló: fenoles, fosfolípidos, carotenoides y tocotrienoles. Los índices de refracción, saponificación, yodo, peróxido y de acidez, fueron 1,48, 189 mg KOH/g, 190, 0,9 meq/kg, 1,11 KOH/g respectivamente. La densidad, materia insaponificable y humedad y materias volátiles fueron 0,9276, 0,27%, 0,05% respectivamente. Los niveles de arsénico y de plomo, no excedieron los límites máximos permisibles. El grupo de ciclofosfamida mostró una cantidad mayor de espermatozoides anormales (P<0,01) con respecto a los grupos de solución salina y NIMET; no se halló diferencia significativa entre los grupos de solución salina y NIMET . Conclusiones. el aceite de Plukenetia volubilis, es rico en ácidos grasos esenciales alfa-linolénico y linoleico, con una óptima proporción omega 6/omega 3, con significativas cantidades de tocoferoles y fitoesteroles los cuales le brindan una estabilidad oxidativa y con características físico-químicas que corroboran su calidad.En este diseño evaluado el aceite de sacha inchi no induce genotóxicidad, podemos decir que su consumo es seguro como alimento.


Objectives. To determine the chemical composition, physical-chemical characteristics and the genotoxic effect of Plukenetia volubilis L. oil. Materials and methods. The profile of fatty acids, tocopherols, sterols, phospholipids, carotenoids, tocotrienols and phenols was evaluated; as well as the physical-chemical characteristics and metallic traces. Genotoxicity was assessed through the sperm head morphology test. For this test, male albino mice were used forming 3 experimental groups of 7 animals each: negative control (saline solution 0.9%), positive control (50 mg / kg / pc / day of cyclophosphamide) and problem group received via oral 0.5 ml sacha inchi oil (NIMET); the substances were administered every 24 hours for 5 days. Results. The oil contains polyunsaturated (81.72%), monounsaturated (10.31%) and saturated (7.67%) fatty acids; being alpha-linolenic (47.35%) and linoleic (34.34%) the most abundant. The most abundant tocopherol and sterol were gammatocopherol and beta-siitosterol respectively, and in a small amount it was found: phenols, phospholipids, carotenoids and tocotrienols. The indices of refraction, saponification, iodine, peroxide and acidity were 1.48, 189 mg KOH / g, 190, 0.9 meq / kg, 1.11 KOH / g respectively. The density, unsaponifiable matter and moisture and volatile materials were 0.9276, 0.27%, 0.05% respectively. The arsenic and lead levels did not exceed the maximum permissible limits. The cyclophosphamide group showed a higher amount of abnormal sperm (P <0.01) with respect to the saline solution and NIMET groups; no significant difference was found between the saline solution and NIMET groups. Conclusions. Plukenetia volubilis oil, is rich in alphalinolenic and linoleic essential fatty acids, with an optimum omega 6 / omega 3 ratio, with significant amounts of tocopherols and phytosterols which provide oxidative stability and physical-chemical characteristics that corroborate its quality. In this evaluated design sacha inchi oil does not induce genotoxicity, we can say that its consumption is safe as food.


Asunto(s)
Animales , Masculino , Ratones , Euphorbiaceae/química , Genotoxicidad , Plantas Medicinales , Cabeza del Espermatozoide , Fitoquímicos , Medicina Tradicional
15.
Rev. med. vet. (Bogota) ; (37): 13-24, jul.-dic. 2018. tab
Artículo en Español | LILACS-Express | LILACS | ID: biblio-1094052

RESUMEN

Resumen Las concentraciones de metales pesados en aves están influenciadas por factores como dieta, migración y tiempo de residencia. En el presente estudio se midieron las concentraciones (en μg(g-1 de peso seco) de los metales pesados cadmio (Cd), níquel (Ni), cobre (Cu), plomo (Pb), cromo (Cr) y zinc (Zn) en sangre de gallo (Gallus gallus domesticus). Para ello se le extrajeron 2 ml de sangre a ocho adultos y siete juveniles, y luego se procesaron con técnicas rutinarias de digestión, vertiendo 0,5 g de sangre en tubos de digestión con 5 ml de una mezcla ácida (180 ml de ácido nítrico y 100 ml de ácido clorhídrico), para lo cual se usó un bloque de calentamiento. Se analizaron en un espectrofotómetro de absorción atómica con flujo de aire-acetileno y corrector de fondo de deuterio. Las concentraciones promedio de metales pesados determinados en la sangre de los gallos adultos y juveniles no mostraron diferencias estadísticamente significativas, pero se pudo evidenciar que el patrón de las concentraciones se distribuyó de distinta manera en cada grupo. En orden descendente: Zn ˃ Ni ˃ Pb ˃ Cu ˃ Cr ˃ Cd, en adultos; mientras que para los juveniles fue: Zn ˃ Pb ˃ Ni ˃ Cu ˃ Cr ˃ Cd. Las concentraciones promedio para cada uno de los metales pesados analizados obtenidos en sangre de gallo fueron similares o estuvieron por debajo de los límites permisibles a los señalados en estudios realizados en otros países. En general, las concentraciones de los metales pesados obtenidos en los gallos no se consideran alarmantes.


Abstract The concentrations of heavy metals in birds are influenced by factors such as diet, migration, and residence time. The present study measured the concentrations (in μg(g-1 of dry weight) of the following heavy metals in the blood of cocks (Gallus gallus domesticus): cadmium (Cd), nickel (Ni), copper (Cu), lead (Pb), chromium (Cr), and zinc (Zn). For the effect, 2 ml of blood was extracted from eight adult and seven juvenile cocks, and then they were processed with routine digestion techniques, pouring 0.5 g of blood into digestion tubes with 5 ml of an acid mixture (180 ml of nitric acid and 100 ml of hydrochloric acid), using a heating block, to analyze them in an atomic absorption spectrophotometer with air-acetylene flow and a deuterium corrector. The average concentrations of heavy metals found in the blood of adult and juvenile cocks did not show statistically significant differences, but it evidenced that the pattern of concentrations was different in each group. In descending order: Zn ˃ Ni ˃ Pb ˃ Cu ˃ Cr ˃ Cd, in adults; and Zn ˃ Pb ˃ Ni ˃ Cu ˃ Cr ˃ Cd, in juveniles. Average concentrations for each one of the analyzed heavy metals obtained in rooster blood were below the permissible limits or were similar to those indicated in studies carried out in other countries. In general, the concentrations of heavy metals found in cocks are not considered alarming.


Resumo As concentrações de metais pesados em aves estão influenciadas por fatores como dieta, migração e tempo de residência. No presente estudo foram medidas as concentrações (em μg(g-1 de peso seco) dos metais pesados cadmio (Cd), níquel (Ni), cobre (Cu), chumbo (Pb), cromo (Cr) e zinco (Zn) em sangue de galo (Gallus gallus domesticus). Para isso, foram extraídos 2 ml de sangue a oito adultos e sete jovens, e logo foram processados com técnicas rotineiras de digestão, vertendo 0,5 g de sangue em tubos de digestão com 5 ml de uma mescla ácida (180 ml de ácido nítrico e 100 ml de ácido clorídrico), utilizando um bloco de aquecimento, para depois analisá-las em um espectrofotômetro de absorção atômica com fluxo de ar-acetileno e corretor de fundo de deutério. As concentrações médias de metais pesados determinados no sangue dos galos adultos e jovens não mostraram diferenças estatisticamente significativas, mas se pôde evidenciar que o padrão das concentrações se distribuiu de forma distinta em cada grupo. Em ordem descendente: Zn ˃ Ni ˃ Pb ˃ Cu ˃ Cr ˃ Cd, em adultos; enquanto que para os jovens foi: Zn ˃ Pb ˃ Ni ˃ Cu ˃ Cr ˃ Cd. As concentrações médias para cada um dos metais pesados analisados obtidos em sangue de galo foram similares ou estiveram abaixo dos limites permitidos aos apontados em estudos realizados em outros países. De modo geral, as concentrações dos metais pesados obtidos nos galos não se consideram alarmantes.

16.
Nutr. hosp ; 35(2): 469-473, mar.-abr. 2018.
Artículo en Español | IBECS | ID: ibc-172761

RESUMEN

Los ftalatos son unos compuestos químicos clasificados como disruptores endocrinos que están presentes en prácticamente todos los entornos de la vida cotidiana. En el campo de la nutrición artificial son relevantes porque se encuentran como plastificantes en las líneas de infusión elaboradas con PVC. Son moléculas lipófilas que se unen débilmente al PVC y, por lo tanto, se extraen fácilmente por los compuestos lipídicos que forman parte de la nutrición tanto parenteral como enteral, tal y como demuestran diversos estudios. Como disruptores endocrinos, afectan directamente a los órganos reproductivos debido a sus efectos antiandrogénicos y estrogénicos. Favorecen la inflamación y el estrés oxidativo y también se relacionan con el desarrollo de obesidad, asma, alteraciones neurológicas y oftalmológicas, colestasis y otras alteraciones gastrointetinales. La legislación establece unos rangos máximos de exposición que están pensados para la exposición diaria; sin embargo, en el entorno médico la exposición sigue un patrón diferente, más puntual y con picos muy altos, para los cuales no hay márgenes descritos, por lo que se recomienda evitar la exposición siempre que sea posible. La industria trabaja en el desarrollo de plastificantes alternativos para los cuales la experiencia de uso es todavía limitada. Actualmente, en el campo de la nutrición artificial se recomienda utilizar líneas de infusión tanto intravenosa como enteral libres de ftalatos


Phthalates are chemical compounds classified as endocrine disruptors which are present in practically every environment of daily life. In the field of artificial nutrition, they are relevant because they are found as plasticizers in infusion lines made with PVC. They are lipophilic molecules which weakly pair with PVC and, therefore, they are easily extracted by the fatty compounds that are part of both the parenteral and enteral nutrition, as various studies show. As endocrine disruptors, they directly affect the reproductive organs because of their antiandrogenic and estrogenic effects. They promote inflammation and oxidative stress and they are also related to the development of obesity, asthma, neurological and ophthalmic disorders, cholestasis and other gastrointestinal disorders. The legislation establishes the highest recommended exposure level for daily exposure; however, in the medical environment the exposure follows a different pattern, more occasional with very high peaks, for which there are no established thresholds, that is why it is recommended to avoid exposure whenever possible. The industry is working on the development of alternative plasticizers, for which the use experience is still limited. Currently, in the field of artificial nutrition it is recommended to use phthalate-free intravenous and enteral infusion lines


Asunto(s)
Humanos , Disruptores Endocrinos/análisis , Alimentación Artificial/métodos , Dibutil Ftalato/efectos adversos , Plastificantes/efectos adversos , Límites Permisibles , Contaminación Química
17.
Huancayo; s.n; 2018. 37 p. tab, graf, ilus.
Tesis en Español | LIPECS | ID: biblio-1050331

RESUMEN

El Servicio de Farmacia del Hospital Nacional Ramiro Prialé Prialé brinda atención a pacientes asegurados de la provincia de Huancayo, lo que hace necesario aplicar medidas higiénicas y de bioseguridad por parte del personal asistencial; frente a lo cual este estudio se planteó como objetivo evaluar la calidad microbiológica del personal asistencial del Hospital Nacional Ramiro Prialé Prialé de Huancayo; para ello se empleó el método analítico, siendo un estudio de tipo básico, transversal, prospectivo y de nivel descriptivo. Se aplicó un diseño descriptivo transversal, analizando 48 muestras de tres superficies corporales (cabello, manos y fosas nasales) de cuatro personas escogidas mediante muestreo no probabilístico intencional entre junio y julio del 2017. Para evaluar la calidad microbiológica se empleó el método de recuento en placa mediante la técnica de hisopado, empleando indicadores de calidad higiénica (bacterias mesófilas viables, mohos y levaduras) e indicadores de calidad higiénico-sanitaria (Escherichia coli y Staphylococcus aureus). El análisis de bacterias mesófilas viables arrojó valores mayores en superficie de cabello (53,3 UFC/placa), mientras que los mohos y levaduras fueron mayores en fosas nasales (43,5 UFC/placa). En todos los casos los recuentos se mantuvieron por debajo de los límites permisibles. Hubo mayor presencia de E. coli en cabello (4,0 UFC/placa) y de S. aureus en manos (5,0 UFC/placa), sobrepasando su límite de permisividad. La comparación con los estándares microbiológicos para personal e instituciones sanitarias permitió establecer que la calidad fue inaceptable en superficie de cabello y manos; siendo aceptable en fosas nasales. Palabras clave: Calidad microbiológica, personal asistencial, aerobios mesófilos, Escherichia coli, Staphylococcus aureus.


Asunto(s)
Humanos , Personal de Salud , Indicadores de Calidad de la Atención de Salud , Higiene , Escherichia coli
18.
J Expo Sci Environ Epidemiol ; 28(1): 69-75, 2018 01.
Artículo en Inglés | MEDLINE | ID: mdl-28513604

RESUMEN

Exposure limit values give the exposure level at which an accepted (or acceptable) number of additional work related diseases are expected. The values are derived from dose-response curves and carry a large amount of uncertainty. In this paper we aim to quantify some of this uncertainty with statistical means. We explore the limit value issued by the European Chemical Agency (ECHA) for occupational exposure to hexavalent chromium, CR(VI). We investigate how the dose-response model and statistical estimation variability influences the data-based fixation of exposure limit values. We also look at the effect of measurement variation on the exposure level itself, where simulation techniques allow to quantify the uncertainty in statistical terms. We demonstrate that statistical uncertainty needs to be taken into account when fixing exposure limit values based on data.


Asunto(s)
Cromo/análisis , Relación Dosis-Respuesta a Droga , Exposición Profesional/análisis , Exposición Profesional/normas , Medición de Riesgo/métodos , Valores Limites del Umbral , Baltimore , Estudios de Cohortes , Simulación por Computador , Monitoreo del Ambiente , Europa (Continente) , Humanos , Modelos Lineales , Neoplasias Pulmonares/inducido químicamente , Concentración Máxima Admisible , Exposición Profesional/efectos adversos , Ohio , Distribución de Poisson , Incertidumbre
20.
Med Pr ; 68(6): 693-703, 2017 Oct 17.
Artículo en Inglés | MEDLINE | ID: mdl-28930303

RESUMEN

BACKGROUND: Presented information about the welding process and equipment, focusing on the emission of electromagnetic field (EMF) with levels significant in terms of the labor safety regulations in force in Poland - the ordinances of the Minister of Family, Labour and Social Policy that came into force on June 27, 2016 and June 29, 2016 - emerged due to harmonization with European Union directive 2013/35/EU of 26 June 2013 of the European Parliament and the Council. They presented methods of determination of the EMF distribution in the welding machine surroundings and analyzed the background knowledge from the available literature. MATERIAL AND METHODS: The subject of the analysis included popular high frequency welders widely used in the industry. Electromagnetic field measurements were performed in the welder operating place (in situ) during machine normal operations, using measurement methods accordant with labor safety regulations in force in Poland and according to the same guidelines, the EMF distributions and parameters having been described. RESULTS: They presented various scenarios of particular, real examples of excessive exposure to EMF in the dielectric welder surroundings and showed solutions, ranging from simple and costless and ending on dedicated electromagnetic shielding systems, which allowed to reduce EMF exposure in some cases of more than 80% (protection zone ranges) or eliminate dangerous zone presence. CONCLUSIONS: It has shown that in the dielectric welders surrounding, significant EMF strength levels may be the result of errors or omissions which often occur during development, installation, operation or modification of welding machines. It has allowed to present the measures that may significantly reduce the exposure to EMF of workers in the welder surroundings. The role of accredited laboratories in helping in such cases was underlined. Med Pr 2017;68(6):693-703.


Asunto(s)
Campos Electromagnéticos , Exposición Profesional/análisis , Monitoreo de Radiación/normas , Soldadura/normas , Unión Europea , Mano/efectos de la radiación , Cabeza/efectos de la radiación , Humanos , Concentración Máxima Admisible , Polonia , Valores Limites del Umbral , Torso/efectos de la radiación
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