A monitoração individual é um procedimento básico de verificação da obediência às diretrizes regulatórias de proteção radiológica. Dosímetros eletrônicos com detectores de estado sólido (DE) têm sido amplamente usados para dosimetria pessoal, inclusive em feixes pulsados de radiação onde a resposta deles ainda não é conhecida e falhas têm sido registradas. Neste trabalho, condições de radiação para testar a resposta de DE em feixes contínuos e pulsados foram estudadas na máquina de raios X de potencial constante Seifert-Pantak HS320 e na máquina de raios X médico VMI Pulsas 800 Plus. Os feixes foram caracterizados em termos de tensão no tubo, camada semirredutora, energia média e taxa de kerma no ar. A coerência metrológica do detector Xi R/F Unfors usado como referência nas medidas de kerma no ar foi verificada contra câmaras de ionização Radcal 10X6-6 a RC-6. Dosímetros eletrônicos RADOS Rad-60, Aloka PDM-111 Thermoelectron e EPD MK2 foram testados quanto ao erro intrínseco relativo e dependência energética em radiações similares às qualidades RQR e RQA da IEC e série N da ISO. Os resultados demonstraram a confiabilidade do dosímetro de estado sólido Unfors Xi R/F, embora sua resposta mostrasse ser afetada em feixes altamente filtrados. Os testes nos DE mostraram que alguns erros intrínsecos relativos em termos de equivalente de dose pessoal, Hp(10), foram maiores que os valores estabelecidos em normas para feixes contínuos. Em feixes pulsados, alguns DE não responderam adequadamente à radiação e apresentaram erros intrínsecos relativos bem altos. Este trabalho ressaltou a necessidade de testes adicionais nos DE, além de limitada calibração em feixes de 137Cs, antes de usá-los em feixes pulsados de raios X. / Personal radiation monitoring is a basic procedure to verify the compliance to regulatory requirements for radiological protection. Electronic personal dosimeters (EPD) based on solid state detectors have largely been used for personnel monitoring; including for pulsed radiation beams where their responses are not well known and deficiencies have been reported. In this work, irradiation conditions for testing the response of EPDs in both continuous and pulsed X-ray beams were studied to be established in a constant potential Seifert-Pantak and in a medical Pulsar 800 Plus VMI X-ray machines. Characterization of X-ray beams was done in terms of tube voltage, half-value layer, mean energy and air kerma rate. A Xi R/F Unfors solid state dosimeter used as reference for air kerma measurements was verified against a RC-6 and 10X6-6 Radcal ionization chambers as far its metrological coherence. Rad-60 RADOS, PDM- 11 Aloka and EPD MK2 Thermoelectron EPDs were selected to be tested in terms of relative intrinsic error and energy response in similar to IEC RQR, IEC RQA and ISO N reference radiations. Results demonstrated the reliability of the solid state Xi R/F Unfors dosimeter to be as reference dosimeter although its response was affected by heavily filtered beams. Results also showed that relative intrinsic errors in the response of the EPDs in terms of personal dose equivalent, Hp(10), were higher than the requirement established for continuous beams. In pulsed beams, some EPDs showed inadequate response and high relative intrinsic errors. This work stressed the need of performing additional checks for EPDs, besides the limited 137Cs beam calibration, before using them in pulsed X-ray beams.

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Adverse health effects from exposure to air pollution, although at present only partly understood, are a global challenge and of widespread concern. Quantifying human exposure to air pollutants is challenging, as ambient concentrations of air pollutants at potentially harmful levels are ubiquitous and subject to high spatial and temporal variability. At the same time, individuals have their very own unique activity-patterns. Hence exposure results from intertwined relationships between environmental and human systems add complexity to the assessment process. It is essential to develop a deeper understanding of individual exposure pathways and situations occurring in people’s everyday lives. This is important especially with regard to exposure and health impact assessment which provide the basis for public health advice and policy development. This thesis describes the development and application of a personal monitoring method to assess exposure to fine particulate matter in a variety of microenvironments. Tools and methods applied are tested with respect to feasibility, intrusiveness, performance and potential for future applications. The development of the method focuses on the application in everyday environments and situations in an attempt to capture as much of the total exposure as possible, across a complete set of microenvironments. Seventeen volunteers took part in the pilot study, collected data and provided feedback on methodology and tools applied. The low-cost particle counter applied showed good agreement with reference instruments when studied in two different environments. Based on the assessment of the two instruments functions to derive particle mass concentration from the original particle number counts have been defined. The application of the devices and tools received positive feedback from the volunteers. Limitations are mainly related to the non-weatherproof design of the particle counter. The collection of time-activity patterns with GPS and time-activity diaries is challenging and requires careful processing. Resulting personal exposure profiles highlight the influence of individual activities and contextual factors. Highest concentrations were measured in indoor environments where people also spent the majority of time. Differences between transport modes as well as between urban and rural areas were identified.

Introdução: A poluição atmosférica é proveniente de complexas interações que envolvem emissões de poluentes atmosféricos e que sabidamente causam consequências negativas para a saúde humana. De acordo com alguns estudos, a exposição à poluição, durante a gestação, pode causar baixo peso ao nascimento e prematuridade. Contudo, não há ainda consenso sobre os períodos de maior susceptibilidade para a exposição à poluição, e quais seriam os seus efeitos nos desfechos do gestação e na determinação do sexo do recém-nascido (RN). Objetivos: Com a finalidade de investigar o impacto da poluição na gestação e, consequentemente, no RN, os objetivos deste projeto são avaliar a influência da exposição à poluição, antes da concepção, na determinação do sexo do RN, e, durante a gestação, nos desfechos do parto e na curva de crescimento da circunferência cefálica (CC) entre o terceiro trimestre e o parto. Métodos: Um estudo prospectivo com 371 gestantes, intitulado ProcriAR, foi realizado na cidade de São Paulo. Os poluentes dióxido de nitrogênio (NO2) e ozônio (O3) foram medidos durante cada trimestre da gestação por meio da utilização de amostradores passivos individuais (APIs). Simultaneamente, foi realizada a análise dos poluentes NO2 e material particulado com tamanho menor que 10 Micro m (MP10) medidos pela estação fixa de ar de Taboão da Serra da Companhia Ambiental do Estado de São Paulo (CETESB), localizada na zona oeste de São Paulo e a mais próxima da residência das gestantes do projeto. Os desfechos avaliados foram: idade gestacional, peso, comprimento e medida da CC do RN; sexo do RN e crescimento do polo cefálico entre o terceiro trimestre e o parto. Quando a variável desfecho era contínua, foi realizada análise linear multivariada, controle de idade gestacional, sexo do RN, idade materna no momento da concepção, índice de massa corporal (IMC), paridade, tabagismo, consumo de álcool, cor, nível de escolaridade completado, estado civil, índice de pulsatilidade (IP) da artéria umbilical no terceiro trimestre, e via de parto para a variável CC. Resultados: Não foram observadas associações entre a exposição ao NO2 e O3, avaliados em cada trimestre da gestação, e a idade gestacional, o peso, o comprimento, a CC ao nascer e o crescimento do polo cefálico fetal entre o terceiro trimestre e o parto. A exposição ao NO2 e MP10 no ano prévio à concepção influenciou na chance de ser do sexo feminino, ou seja, para cada aumento de 1 unidade do poluente do NO2, constatou-se um aumento de 10% na chance de ser do sexo feminino (Razão de chances (RC) = 1,100; intervalo de confiança (IC) de 95% = 1,040, 1,164; p = 0,001). Em relação ao MP10, para cada aumento de 1 unidade desse poluente, observou-se um aumento de 18 % na chance de ser do sexo feminino (RC = 1,176; IC de 95% = 1,054, 1,311; p = 0,004). Conclusão: Nossos resultados sugerem que, no ambiente de São Paulo, a exposição à poluição no ano prévio à concepção esteve associada à determinação do sexo do RN / Background: Ambient pollution may lead to adverse obstetric outcomes, such as premature birth and low birth weight. Objectives: To determine the influence of maternal air pollution exposure on sex ratio, on birth outcomes and on the growth curve of cephalic pole between the third trimester and the birth. Methods: ProcriAR, a prospective cohort study of 371 pregnant women, was conducted in the city of São Paulo. Nitrogen dioxide (NO2) and ozone (O3) were measured during each trimester using passive personal monitors. At the same time, NO2 and particulate matter lower than 10 Micro m (PM10) were measured by a fixed station. We evaluated the gestational age, birth weight, birth lenght, head circumference, newborn sex and the growth curve of cephalic pole between the third trimester and the birth. When the outcome variable was continuous, multivariate analysis was performed, controlling for gestational age, newborn sex, maternal age at conception, body mass index, parity, smoking, alcohol consumption, race, highest education level completed, marital status, umbilical artery pulsatility values at third trimester and type of delivery for the outcome head circumference. We used multiple logistic regression models to evaluate the association of being female based on a quantitative increase in pollutant concentration, controlling for maternal age at conception, parity and smoking. Results: Elevated exposure to pollutants NO2 and PM10 were associated with increased odds of being female. Each unit increase of NO2 exposure increased the odds of being female by 10% (odds ratio (OR) = 1,100, 95% confidence interval (CI) = 1,040, 1,164; p = 0,001) and each unit increase of PM10 increased by 18% (OR = 1,176, 95% CI 1,054, 1,311, p = 0,004). Conclusion: In São Paulo, maternal exposure to pollutants prior to conception was significantly associated with the odds of being female

The thesis deals with the issue of operative dosimetry, to be specific, with personal dosimetry. The objective of the thesis is to compare several parameters, such as the dose, direction and energy dependence, in two types of electronic dosimeters made by the firm Siemens (type EPD1) and by the firm MGP Instruments (type DMC 2000XB). In the first section of my thesis the personal monitoring and related data such as quantities used to monitor external irradiation are introduced. In the next section the operative monitoring, focused mainly on electronic but also on thermoluminescent and radiophotoluminescent dosimetry, is described. The results of the irradiation (exposure) of electronic personal dosimeters of types EPD1 and DMC 2000XB are included in the thesis and the measured values are statistically processed. The dose, direction and energy dependence of both types of these dosimeters is evaluated and put into diagrams.