Browsing by Author "Albuquerque, Paula"
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- Adaptação de um instrumento de avaliação qualitativa do risco químico em anatomia patológicaPublication . Ferro, Amadeu Borges; Ladeira, Carina; Viegas, Carla; Ribeiro, Cátia; Figueira, Edite; Albuquerque, Paula; Quintino, FernandaOs agentes químicos são frequentemente manipulados nos laboratórios de anatomia patológica. Existem diversos estudos que comprovam a existência de uma associação entre a exposição a produtos químicos e o desenvolvimento de determinadas patologias, demonstrando, assim, a importância da avaliação e monitorização deste tipo de agentes. Pretendeu-se, com este trabalho, caracterizar a exposição dos técnicos de anatomia patológica aos agentes químicos através de um instrumento baseado no International Chemical Control Toolkit, no serviço de histopatologia dos laboratórios de anatomia patológica da região de Lisboa e Vale do Tejo.
- Análise das implicações para a saúde humana do uso das nanotecnologiasPublication . Albuquerque, Paula; Gomes, J. F.As nanotecnologias representam um importante potencial para a promoção da qualidade de vida e da competitividade industrial na Europa. Um material com nanodimensões tem uma relação superfície/volume que vai alterar as suas propriedades físicas, químicas, ópticas e magnéticas do material e fazer com que este reaja de maneira diferente e de uma forma desconhecida com os organismos e o ambiente. As nanopartículas são capazes de entrar facilmente no organismo através da pele, pulmões e capazes de originar efeitos no ambiente a nível de água, solo e ar. A nível de saúde muitos dos estudos são projectados como uma analogia à exposição humana ao quartzo, e ao amianto, e também no que concerne à poluição do ar e aplicações médicas (fármacos) com nanopartículas. Relativamente ao ambiente, existem ainda poucos estudos, mas ainda assim, surgem certas evidências que relatam, que dependendo das características e tipos de interacção dos nanomateriais com ecossistemas poderá ocorrer entre outros, retenção dos mesmos no ambiente. A investigação é ainda diminuta, fornecendo poucas evidências, no entanto, existem factos e resultados indicadores de que os efeitos na saúde e ambiente poderão ser prejudicais. A prevenção da doença e do ambiente deverão ser salvaguardadas e serem objecto de intervenções prioritárias. O conhecimento das relações existentes entre nanopartículas emitidas para o ar e a saúde humana, em diferentes condições ambientais, é de importância primordial para melhorar as estimativas de exposição, assim como para o desenvolvimento de estratégias eficientes de controlo para reduzir a exposição humana, os riscos sobre a saúde, e, também para estabelecer, avaliar e melhorar os regulamentos e a legislação relativa à qualidade do ar, emissões e a utilização de nanomateriais em produtos de consumo corrente.
- Application of a control banding tool for risk level assessment and control of nanoparticles exposure in welding operationsPublication . Gomes, João; Pereira, Catarina; Albuquerque, Paula; Miranda, RosaScope of study: welding operations result in harmful emissions of nanoparticles; the aim of emissions monitorisation is to evaluate exposure levels and to derive protection measures in order to protect exposed workers; however, the traditional approach of comparing measured concentrations with exposure limits cannot be used; but risk levels can be quantified by using Control Banding Strategies.
- Characterization of airborne emission of nanoparticles in the ceramic industry in PortugalPublication . Esteves, Hélder; Bordado, J.; Gomes, João; Miranda, R.; Albuquerque, PaulaThe objective of this study was to evaluate occupational exposure to nanoparticles during some tasks performed in different production processes of different ceramic industries in Portugal, to select the places of greatest occupational exposure through the analysis of the sampled data, to verify what is the pulmonary accumulation in these places, to identify the composition of the released nanoparticles, apply a Control Banding Tool and try to understand which companies require more risk control measures. The study was carried out in three different national ceramics production industries, one for sanitary ceramics production, another for porcelain crockery production and finally another for the production of ornamental crockery (red paste). It is concluded that occupational exposure values to nanoparticles are high in all cases and that nanoparticles are very small in size (11.5 to 15.4 nm). Existing risk control measures are insufficient and verified risk levels are high (Risk Level 3 and 4). The chemical composition of the analyzed nanoparticles is similar regardless of the typology of the ceramic production plant and their chemical composition as a percentage of certain materials has a direct influence on crystallinity.
- Characterization of airborne emission of nanoparticles in the ceramic industry in PortugalPublication . Esteves, H.; Bordado, J.; Gomes, João; Miranda, R.; Albuquerque, PaulaThe objective of this study was to evaluate occupational exposure to nanoparticles during some tasks performed in different production processes of different ceramic industries in Portugal, to select the places of greatest occupational exposure through the analysis of the sampled data, to verify what is the pulmonary accumulation in these places, to identify the composition of the released nanoparticles, apply a Control Banding Tool and try to understand which companies require more risk control measures. The study was carried out in three different national ceramics production industries, one for sanitary ceramics production, another for porcelain crockery production, and finally another for the production of ornamental crockery (red paste). It is concluded that occupational exposure values to nanoparticles are high in all cases and that nanoparticles are very small in size (11.5 to 15.4 nm). Existing risk control measures are insufficient and verified risk levels are high (Risk Level 3 and 4). The chemical composition of the analyzed nanoparticles is similar regardless of the typology of the ceramic production plant and their chemical composition as a percentage of certain materials has a direct influence on crystallinity.
- Characterization of airborne particles generated from metal active gas welding processPublication . Guerreiro, C.; Gomes, João; Carvalho, P.; Santos, T. J. G.; Miranda, R. M.; Albuquerque, PaulaThis study is focused on the characterization of particles emitted in the metal active gas welding of carbon steel using mixture of Ar + CO2, and intends to analyze which are the main process parameters that influence the emission itself. It was found that the amount of emitted particles (measured by particle number and alveolar deposited surface area) are clearly dependent on the distance to the welding front and also on the main welding parameters, namely the current intensity and heat input in the welding process. The emission of airborne fine particles seems to increase with the current intensity as fume-formation rate does. When comparing the tested gas mixtures, higher emissions are observed for more oxidant mixtures, that is, mixtures with higher CO2 content, which result in higher arc stability. These mixtures originate higher concentrations of fine particles (as measured by number of particles by cm 3 of air) and higher values of alveolar deposited surface area of particles, thus resulting in a more severe worker's exposure.
- Determination of airborne nanoparticles from welding operationsPublication . Gomes, João; Albuquerque, Paula; Miranda, Rosa Maria Mendes; Vieira, Maria Teresa FreireThe aim of this study is to assess the levels of airborne ultrafine particles emitted in welding processes (tungsten inert gas [TIG], metal active gas [MAG] of carbon steel, and friction stir welding [FSW] of aluminum) in terms of deposited area in pulmonary alveolar tract using a nanoparticle surface area monitor (NSAM) analyzer. The obtained results showed the dependence of process parameters on emitted ultrafine particles and demonstrated the presence of ultrafine particles compared to background levels. Data indicated that the process that resulted in the lowest levels of alveolar deposited surface area (ADSA) was FSW, followed by TIG and MAG. However, all tested processes resulted in significant concentrations of ultrafine particles being deposited in humans lungs of exposed workers.
- Determination of airborne nanoparticles in elderly care centresPublication . Almeida-Silva, Marina; Almeida, Susana Marta; Gomes, J. F.; Albuquerque, Paula; Wolterbeek, H. Th.According to numerous studies, airborne nanoparticles have a potential to produce serious adverse human health effects when deposited into the respiratory tract. The most important parts of the lung are the alveolar regions with their enormous surface areas and potential to transfer nanoparticles into the blood stream. These effects may be potentiated in case of the elderly, since this population is more susceptible to air pollutants in general and more to nanoparticles than larger particles. The main goal of this investigation was to determine the exposure of institutionalized elders to nanoparticles using Nanoparticle Surface Area Monitor (NSAM) equipment to calculate the deposited surface area (DSA) of nanoparticles into elderly lungs. In total, 193 institutionalized individuals over 65 yr of age were examined in four elderly care centers (ECC). The occupancy daily pattern was achieved by applying a questionnaire, and it was concluded that these subjects spent most of their time indoors, including the bedroom and living room, the indoor microenvironments with higher prevalence of elderly occupancy. The deposited surface area ranged from 10 to 46 μm2/cm3. The living rooms presented significantly higher levels compared with bedrooms. Comparing PM10 concentrations with nanoparticles deposited surface area in elderly lungs, it is conceivable that living rooms presented the highest concentration of PM10 and were similar to the highest average DSA. The temporal distribution of DSA was also assessed. While data showed a quantitative fluctuation in values in bedrooms, high peaks were detected in living rooms.
- Determination of airborne nanoparticles in elderly care centresPublication . Almeida-Silva, Marina; Almeida, Susana Marta; Gomes, João; Albuquerque, Paula; Wolterbeek, H. T.According to numerous studies, airborne nanoparticles have a potential to produce serious adverse human health effects when deposited into the respiratory tract. The most important parts of the lung are the alveolar regions with their enormous surface areas and potential to transfer nanoparticles into the blood stream. These effects may be potentiated in case of the elderly, since this population is more susceptible to air pollutants in general and more to nanoparticles than larger particles. The main goal of this investigation was to determine the exposure of institutionalized elders to nanoparticles using Nanoparticle Surface Area Monitor (NSAM) equipment to calculate the deposited surface area (DSA) of nanoparticles into elderly lungs. In total, 193 institutionalized individuals over 65 yr of age were examined in four elderly care centers (ECC). The occupancy daily pattern was achieved by applying a questionnaire, and it was concluded that these subjects spent most of their time indoors, including the bedroom and living room, the indoor microenvironments with higher prevalence of elderly occupancy. The deposited surface area ranged from 10 to 46 mu m(2)/cm(3). The living rooms presented significantly higher levels compared with bedrooms. Comparing PM10 concentrations with nanoparticles deposited surface area in elderly lungs, it is conceivable that living rooms presented the highest concentration of PM10 and were similar to the highest average DSA. The temporal distribution of DSA was also assessed. While data showed a quantitative fluctuation in values in bedrooms, high peaks were detected in living rooms.
- Environmental monitoring and biomarkers of exposure to styrene in chemical industryPublication . Fernandes, Daniela; Meneses, Márcia; Albuquerque, Paula; Barros, MiguelABSTRACT - Biomarkers of exposure to chemicals, such as styrene, allows to estimate the exposure to a particular compound by measuring the compound or it(s) metabolite(s) in body fluids. As an example, the determination of mandelic acid and phenylglyoxylic acid in urine. Indicators of genotoxicity are categorized as: (a) DNA and protein adducts; (b) DNA strand breaks. Styrene metabolism is initiated by Cytochrome P450 enzymes mediated by the oxidation of styrene to a reactive metabolite, the styrene-7,8-oxide. This study aims to review the environmental monitoring, complemented with biomarkers of exposure in order to understand its correlation and styrene genotoxicity. Systematic searches were performed to identify studies of occupational exposure to styrene and health effects in workers of chemical industries. To determine styrene air concentration, several studies used a personal air sampling method. A significant correlation has been found between styrene air concentration and mandelic and phenylglyoxylic acid concentration in urine. A significant relationship was found between individual levels of mandelic acid and phenylglyoxylic acid and styrene-7,8-oxide adducts to N-terminal valine in hemoglobin among exposed individuals. A strong correlation was also found between the frequency of DNA single-strand breaks, in mononuclear leukocytes, and styrene airborne level. The relationship between DNA damage, persistence and repair is complex, which complicates the relevance evaluation of potential genotoxic exposures difficult. There is conflicting evidence on the relationship between genotoxic response and exposure level. In future individual susceptibility studies, the individual genotypes associated with the metabolic route and DNA damage of styrene (metabolizing enzymes and DNA repair enzymes) should be analyzed. From the analysis of several studies it was found that indeed there is a strong correlation between the exposure levels and exposure biomarkers; however, no evidence was found regarding the styrene genotoxicity.
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