Exposure assessment: the influence of environmental monitoring methodology

Exposure assessment is an important step of risk assessment process and has evolved more quickly than perhaps any aspect of the four-step risk paradigm (hazard identification, exposure assessment, dose-response analysis, and risk characterization). Nevertheless, some epidemiological studies have associated adverse health effects to a chemical exposure with an inadequate or absent exposure quantification. In addition to the metric used, the truly representation of exposure by measurements depends on: the strategy of sampling, random collection of measurements, and similarity between the measured and unmeasured exposure groups. Two environmental monitoring methodologies for formaldehyde occupational exposure were used to assess the influence of metric selection in exposure assessment and, consequently, in risk assessment process.

Are air-borne mycotoxins a public health concern in Portugal?

Introduction - Microscopic filamentous fungi, under suitable environmental conditions, can lead to the production of highly toxic chemical substances, commonly known as mycotoxins. The most widespread and studied mycotoxins are metabolites of some genera of moulds such as Aspergillus, Penicillium and Fusarium. Quite peculiar conditions may influence mycotoxin biosynthesis, such as climate, geographical location, cultivation practices, storage and type of substrate. Toxicity has been extensively investigated for the most important mycotoxins, such as aflatoxins, ochratoxin A and Fusarium toxins, and much information derived from toxicokinetics in animal models has also been obtained. The adverse effects are mainly related to genotoxicity, carcinogenicity, mutagenicity, teratogenicity and immunotoxicity. Aim of the study - To identify fungal species able to produce important mycotoxins in different Portuguese settings.

Neutron activation analysis of wheat samples

The deficiency of essential micronutrients and excess of toxic metals in cereals, an important food items for human nutrition, can cause public health risk. Therefore, before their consumption and adoption of soil supplementation, concentrations of essential micronutrients and metals in cereals should be monitored. This study collected soil and two varieties of wheat samples–Triticum aestivum L. (Jordão/bread wheat), and Triticum durum L. (Marialva/durum wheat) from Elvas area, Portugal and analyzed concentrations of As, Cr, Co, Fe, K, Na, Rb and Zn using Instrumental Neutron Activation Analysis (INAA) to focus on the risk of adverse public health issues. The low variability and moderate concentrations of metals in soils indicated a lower significant effect of environmental input on metal concentrations in agricultural soils. The Cr and Fe concentrations in soils that ranged from 93–117 and 26,400–31,300 mg/kg, respectively, were relatively high, but Zn concentration was very low (below detection limit <22 mg/kg) indicating that soils should be supplemented with Zn during cultivation. The concentrations of metals in roots and straw of both varieties of wheat decreased in the order of K>Fe>Na>Zn>Cr>Rb>As>Co. Concentrations of As, Co and Cr in root, straw and spike of both varieties were higher than the permissible limits with exception of a few samples. The concentrations of Zn in root, straw and spike were relatively low (4–30 mg/kg) indicating the deficiency of an essential micronutrient Zn in wheat cultivated in Portugal. The elemental transfer from soil to plant decreases with increasing growth of the plant. The concentrations of various metals in different parts of wheat followed the order: Root>Straw>Spike. A few root, straw and spike samples showed enrichment of metals, but the majority of the samples showed no enrichment. Potassium is enriched in all samples of root, straw and spike for both varieties of wheat. Relatively to the seed used for cultivation, Jordão presented higher transfer coefficients than Marialva, in particular for Co, Fe, and Na. The Jordão and Marialva cultivars accumulated not statistically significant different concentrations of different metals. The advantages of using INAA are the multielementality, low detection limits and use of solid samples (no need of digestion).

A simulation study on the abatement of CO2 emissions by de-absorption with monoethanolamine

Because of the adverse effect of CO2 from fossil fuel combustion on the earth's ecosystems, the most cost-effective method for CO2 capture is an important area of research. The predominant process for CO2 capture currently employed by industry is chemical absorption in amine solutions. A dynamic model for the de-absorption process was developed with monoethanolamine (MEA) solution. Henry's law was used for modelling the vapour phase equilibrium of the CO2, and fugacity ratios calculated by the Peng-Robinson equation of state (EOS) were used for H2O, MEA, N-2 and O-2. Chemical reactions between CO2 and MEA were included in the model along with the enhancement factor for chemical absorption. Liquid and vapour energy balances were developed to calculate the liquid and vapour temperature, respectively.

Fungal contamination of poultries litter: a public health problem

Exposure to certain fungi can cause human illness. Fungi cause adverse human health effects through three specific mechanisms: generation of a harmful immune response (e.g., allergy or hypersensitivity pneumonitis); direct infection by the fungal organism; by toxic-irritant effects from mold byproducts, such as mycotoxins. In Portugal there is an increasingly industry of large facilities that produce whole chickens for domestic consumption and only few investigations have reported on fungal contamination of the poultry litter. The material used for poultry litter is varied but normally can be constitute by: pine shavings; sawdust of eucalyptus; other types of wood; peanut; coffee; sugar cane; straw; hay; grass; paper processed. Litter is one of the most contributive factors to fungal contamination in poultries. Spreading litter is one of the tasks that normally involve higher exposure of the poultry workers to dust, fungi and their metabolites, such as VOC’s and mycotoxins. After being used and removed from poultries, litter is ploughed into agricultural soils, being this practice potentially dangerous for the soil environment, as well for both humans and animals. The goal of this study was to characterize litter’s fungal contamination and also to report the incidence of keratinophilic and toxigenic fungi.

Aspiração manual de trombos no enfarte agudo do miocárdio com supradesnivelamento segmento ST: impacto da técnica de aspiração manual de trombos na reperfusão do miocárdio durante a intervenção coronária percutânea primária

Mestrado em Tecnologia de Diagnóstico e Intervenção Cardiovascular. Área de especialização: Intervenção Cardiovascular.

Checklist cirúrgica: contributo para uma intervenção na área da segurança do doente

Mestrado em Intervenção Sócio-Organizacional na Saúde - Área de especuialização: Políticas de administração e gestão de serviços de saúde.

Intervenção coronária percutânea no enfarte agudo do miocárdio: influência no prognóstico dos doentes

Mestrado em Tecnologia de Diagnóstico e Intervenção Cardiovascular. Área de especialização: Intervenção Cardiovascular.

Fungal and microbial volatile organic compounds exposure assessment in a waste sorting plant

In the management of solid waste, pollutants over a wide range are released with different routes of exposure for workers. The potential for synergism among the pollutants raises concerns about potential adverse health effects, and there are still many uncertainties involved in exposure assessment. In this study, conventional (culture-based) and molecular real-time polymerase chain reaction (RTPCR) methodologies were used to assess fungal air contamination in a waste-sorting plant which focused on the presence of three potential pathogenic/toxigenic fungal species: Aspergillus flavus, A. fumigatus, and Stachybotrys chartarum. In addition, microbial volatile organic compounds (MVOC) were measured by photoionization detection. For all analysis, samplings were performed at five different workstations inside the facilities and also outdoors as a reference. Penicillium sp. were the most common species found at all plant locations. Pathogenic/toxigenic species (A. fumigatus and S. chartarum) were detected at two different workstations by RTPCR but not by culture-based techniques. MVOC concentration indoors ranged between 0 and 8.9 ppm (average 5.3 ± 3.16 ppm). Our results illustrated the advantage of combining both conventional and molecular methodologies in fungal exposure assessment. Together with MVOC analyses in indoor air, data obtained allow for a more precise evaluation of potential health risks associated with bioaerosol exposure. Consequently, with this knowledge, strategies may be developed for effective protection of the workers.

Fungal contamination of poultry litter: a public health problem

Although numerous studies have been conducted on microbial contaminants associated with various stages related to poultry and meat products processing, only a few reported on fungal contamination of poultry litter. The goals of this study were to (1) characterize litter fungal contamination and (2) report the incidence of keratinophilic and toxigenic fungi presence. Seven fresh and 14 aged litter samples were collected from 7 poultry farms. In addition, 27 air samples of 25 litters were also collected through impaction method, and after laboratory processing and incubation of collected samples, quantitative colony-forming units (CFU/m3) and qualitative results were obtained. Twelve different fungal species were detected in fresh litter and Penicillium was the most frequent genus found (59.9%), followed by Alternaria (17.8%), Cladosporium (7.1%), and Aspergillus (5.7%). With respect to aged litter, 19 different fungal species were detected, with Penicillium sp. the most frequently isolated (42.3%), followed by Scopulariopsis sp. (38.3%), Trichosporon sp. (8.8%), and Aspergillus sp. (5.5%). A significant positive correlation was found between litter fungal contamination (CFU/g) and air fungal contamination (CFU/m3). Litter fungal quantification and species identification have important implications in the evaluation of potential adverse health risks to exposed workers and animals. Spreading of poultry litter in agricultural fields is a potential public health concern, since keratinophilic (Scopulariopsis and Fusarium genus) as well as toxigenic fungi (Aspergillus, Fusarium, and Penicillium genus) were isolated.

Assessment of patient dose in digital systems

The assessment of patient dose has gained increased attention, still being an issue of concern that arises from the use of digital systems. The development of digital technology offers the possibility for a reduction of radiation dose around 50% without loss in image quality when compared to a conventional screen–film system. Digital systems give an equivalent or superior diagnostic performance and also several other advantages, but the risk of overexposure with no adverse effect on image quality could be present. This chapter refers to the management of patient dose and provides an explanation of dose-related concepts. In this chapter, exposure influence in dose and image representation and the effects of radiation exposure are also discussed.

Desvio de posicionamento em radioterapia para patologias de cabeça e pescoço e próstata: revisão de literatura

Introdução – Numa era em que os tratamentos de Radioterapia Externa (RTE) exigem cada vez mais precisão, a utilização de imagem médica permitirá medir, quantificar e avaliar o impacto do erro provocado pela execução do tratamento ou pelos movimentos dos órgãos. Objetivo – Analisar os dados existentes na literatura acerca de desvios de posicionamento (DP) em patologias de cabeça e pescoço (CP) e próstata, medidos com Cone Beam Computed Tomography (CBCT) ou Electronic Portal Image Device (EPID). Metodologia – Para esta revisão da literatura foram pesquisados artigos recorrendo às bases de dados MEDLINE/PubMed e b-on. Foram incluídos artigos que reportassem DP em patologias CP e próstata medidos através de CBCT e EPID. Seguidamente foram aplicados critérios de validação, que permitiram a seleção dos estudos. Resultados – Após a análise de 35 artigos foram incluídos 13 estudos e validados 9 estudos. Para tumores CP, a média (μ) dos DP encontra-se entre 0,0 e 1,2mm, com um desvio padrão (σ) máximo de 1,3mm. Para patologias de próstata observa-se μDP compreendido entre 0,0 e 7,1mm, com σ máximo de 7,5mm. Discussão/Conclusão – Os DP em patologias CP são atribuídos, maioritariamente, aos efeitos secundários da RTE, como mucosite e dor, que afetam a deglutição e conduzem ao emagrecimento, contribuindo para a instabilidade da posição do doente durante o tratamento, aumentando as incertezas de posicionamento. Os movimentos da próstata devem-se principalmente às variações de preenchimento vesical, retal e gás intestinal. O desconhecimento dos DP afeta negativamente a precisão da RTE. É importante detetá-los e quantificá-los para calcular margens adequadas e a magnitude dos erros, aumentando a precisão da administração de RTE, incluindo o aumento da segurança do doente. - ABSTRACT - Background and Purpose – In an era where precision is an increasing necessity in external radiotherapy (RT), modern medical imaging techniques provide means for measuring, quantifying and evaluating the impact of treatment execution and movement error. The aim of this paper is to review the current literature on the quantification of setup deviations (SD) in patients with head and neck (H&N) or prostate tumors, using Cone Beam Computed Tomography (CBCT) or Electronic Portal Image Device (EPID). Methods – According to the study protocol, MEDLINE/PubMed and b-on databases were searched for trials, which were analyzed using selection criteria based on the quality of the articles. Results – After assessment of 35 papers, 13 studies were included in this analysis and nine were authenticated (6 for prostate and 3 for H&N tumors). The SD in the treatment of H&N cancer patients is in the interval of 0.1 to 1.2mm, whereas in prostate cancer this interval is 0.0 to 7.1mm. Discussion – The reproducibility of patient positioning is the biggest barrier for higher precision in RT, which is affected by geometrical uncertainty, positioning errors and inter or intra-fraction organ movement. There are random and systematic errors associated to patient positioning, introduced since the treatment planning phase or through physiological organ movement. Conclusion – The H&N SD are mostly assigned to the Radiotherapy adverse effects, like mucositis and pain, which affect swallowing and decrease secretions, contributing for the instability of patient positioning during RT treatment and increasing positioning uncertainties. Prostate motion is mainly related to the variation in bladder and rectal filling. Ignoring SD affects negatively the accuracy of RT. Therefore, detection and quantification of SD is crucial in order to calculate appropriate margins, the magnitude of error and to improve accuracy in RTE and patient safety.

Occupational exposure to poultry dust and effects on the respiratory system in workers

Farmers are occupationally exposed to many respiratory hazards at work and display higher rates of asthma and respiratory symptoms than other workers. Dust is one of the components present in poultry production that increases risk of adverse respiratory disease occurrence. Dust originates from poultry residues, molds, and feathers and is biologically active as it contains microorganisms. Exposure to dust is known to produce a variety of clinical responses, including asthma, chronic bronchitis, chronic airways obstructive disease (COPD), allergic alveolitis, and organic dust toxic syndrome (ODTS). A study was developed to determine particle contamination in seven poultry farms and correlate this with prevalence rate of respiratory defects and record by means of a questionnaire the presence of clinical symptoms associated with asthma and other allergy diseases by European Community Respiratory Health Survey. Poultry farm dust contamination was found to contain higher concentrations of particulate matter (PM) PM5 and PM10. Prevalence rate of obstructive pulmonary disorders was higher in individuals with longer exposure regardless of smoking status. In addition, a high prevalence for asthmatic (42.5%) and nasal (51.1%) symptoms was noted in poultry workers. Data thus show that poultry farm workers are more prone to suffer from respiratory ailments and this may be attributed to higher concentrations of PM found in the dust. Intervention programs aimed at reducing exposure to dust will ameliorate occupational working conditions and enhance the health of workers.

Exposure to particles in Portuguese swine production

Several studies have shown that human exposures to airbome dust and microorganisms, such as bacteria and fungi, can cause respiratory diseases. Agricultural workers have been found to be at high risk of exposures to airborne particles. From a human health perspective dust exposure in pig farming is the most important risk because of the large number of workers needed in pig production and the increasing number of working hours inside enclosed buildings. In the pig buildings, particulate matters like dust play a role in not only deteriorating indoor air quality but also can cause an adverse health effect on workers. Generally, dust is recognized to adsorb and transport odorous compounds and biological agents. The aim of this study was to determine particles contamination in 7 swine farms located in Lisbon district, Portugal.

Fungal contamination: comparation between Portuguese poultries and swines

Animal confinement tends to increase the overall microbial load in the production environment caused by high amounts of feed and organic residuals (manure and wastewater) present in those environments. The number of animais and the handling and management required to work in these settings also contribute to enhance that microbial ioad. Animal housing typically exposes workers to substantial concentrations of bioaerosols, such as fungi and their metabolites. Therefore, agricultural workers, and especially pig and poultry farmers, are at increased risk of occupational respiratory diseases. Exposure to bioaerosols in poultries and swines may vary depending upon the stage of the animals' growth, density, manure management procedures, litter type and used floor coverage, among others. Gathering temporal information about the quantity and the composition of fungal load is necessary to better understand the relationship between these factors and adverse health symptoms of workers. This study aimed to characterize and compare fungal contamination between these two different settings.