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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
21

Etude sur les déterminants professionnels agricoles et leurs effets sur la reproduction et le développement de l'enfant / Negative effects of agricultural exposures on human reproduction and child development

Pons, Romain 19 December 2018 (has links)
Les expositions professionnelles agricoles, et notamment l’exposition aux pesticides, ont été associées à divers effets négatifs, sur la fertilité, le déroulement de la grossesse et le développement de l’enfant. Peu d’études se sont intéressées à des activités agricoles spécifiques excepté le travail sous serre et la floriculture et aucune n’a été à ce jour conduite en France. (1) L’interrogation de plus de 800 femmes, incluses dans la cohorte AGRIculture & CANcer (AGRICAN) et ayant eu une grossesse depuis l’inclusion (2005), grâce à 2 questionnaires rétrospectifs a montré un allongement du délai nécessaire à concevoir en lien avec l’emploi sur une exploitation agricole, le travail de nuit ou l’exposition à des vibrations. Des augmentations de risque d’avortements spontanés et de malformations ont également été observées mais restent à confirmer. (2) Le développement d’une méthode d’analyse multi-résidus a permis de mesurer 25 pesticides différents parmi 116 recherchés dans les urines de femmes travaillant sur des exploitations de poly-culture élevage. Les herbicides étaient les plus fréquemment détectés, notamment en lien avec la présence de maïs sur l’exploitation ou de tâches réalisées au contact des animaux d’élevage. Le glyphosate ou son métabolite AMPA étaient retrouvés dans 85% des échantillons.Un projet de recherche poursuivra les travaux engagés en s’intéressant au développement cognitif des enfants nés depuis 2005. / Agricultural exposures, including pesticide exposure, have been associated with several negative effects on fertility, pregnancy and child development. Few studies focused on specific agricultural activity excepted floriculture and working in greenhouse and none was conducted in France. (1) More than 800 women, enroled in the AGRIculture & CANcer (AGRICAN) cohort and who reported a pregnancy since enrolment (2005) agreed to fill in 2 questionnaires. An increase of time to pregnancy was observed for women who worked on a farm, for those exposed to night work and to vibrations. Increased risks of spontaneous abortions or abnormalities were also observed in relation to agricultural work but these results need to be confirmed. (2) Multi-residue analytical method was developed and applied to women of childbearing age, working in crop-livestock farms. Twenty-five pesticides or metabolites were detected among 116 measured in urine samples. Herbicides were the most frequently detected, especially when women worked on corn-crop farms or were involved in breeding tasks. Glyphosate or its metabolite AMPA were detected in 85% of urine samples.Future project will allow us to investigate cognitive development of children born since 2005.
22

Exposure to respirable crystalline silica amongst stope employees in an underground gold mine between July 2008 and June 2010

Kesilwe, Senki Benjamin 12 February 2014 (has links)
A research report submitted to the Faculty of Health Sciences, School of Public Health, University of the Witwatersrand, Johannesburg, in partial fulfillment of the requirements for the degree of Master of Public Health: Occupational Hygiene, Johannesburg, 2012 / The aim of the study was to determine if the gold mine under study achieved the 2008 elimination of silicosis occupational hygiene milestones as set out by the South African mining industry in 2003. To identify high risk quartz exposed occupations within the conventional stope and TM³ stope employees of an underground gold mine between July 2008 and June 2010; to describe the personal quartz exposure of conventional stope and TM³ stope employees in an underground gold mine between July 2008 and June 2010; and to compare the time weighted average (TWA) quartz exposures between the conventional stope and TM³ stope to the Department of Mineral Resources-Occupational Exposure Limit (DMR-OEL) of 0.1 mg/m3, the National Institute of Occupational Safety and Health-Recommended Exposure Limit (NIOSH-REL) of 0.05 mg/m3 and the American Conference of Government Industrial Hygienists-Threshold Limit Value (ACGIHTLV) of 0.025 mg/m3.
23

Coal tar pitch volatiles exposure in a petrochemical refinery plant: a task based exposure assessment

Makgatho, Michael 23 March 2009 (has links)
This study describes tripper car operators’ exposure to coal tar pitch volatiles at an operation at Coal Distribution Steam Plant that involves the use of coal tar mix to feed as fuel the steam generating boilers. A cross-sectional task-based exposure assessment approached was used. The objectives of this study were to monitor tripper car operators’ exposures to coal tar pitch volatiles as benzene soluble fraction and to then compare the measured concentrations with the occupational exposure limit. The general aim of the study was to accumulate data about employee exposure to coal tar pitch volatiles in South African Petrochemical Refineries. A total of 56 samples was collected and analyzed for coal tar pitch volatiles – benzene soluble fraction. Of the 56 samples, 41 were personal samples collected on the breathing zones of the workers and 15 samples were field blank samples. The method used for the collection of the samples was the United States Department of Labor, Occupational Safety & Health Administration Method 58. In South Africa the available occupational exposure limit for coal tar pitch volatiles is the time weighted average occupational exposure limit – recommended limit for cyclohexane soluble fraction which is 0.14 mg/m3. For the evaluation of personal exposure to compare with the occupational exposure limit, the UK Health & Safety Executive Method for the Determination of Hazardous Substances (MDHS) 68 was adopted in the past to monitor workplace air. This method was since withdrawn by the Health & Safety Executive after research conducted by the Health & Safety Laboratory revealed that unacceptable variability were introduced into the method due to the small mass changes involved and the difficulty in accurately weighing the filters before and after the cyclohexane extraction. Due to the unavailability of a suitable and acceptable method to assess workers’ exposure to coal tar pitch volatiles – cyclohexane soluble fraction to compare to the South African occupational exposure limit, the Occupational Safety & Health Administration Method Number 58 was used during this study for the collection of the samples. This is a validated method. This method follows a similar approach as the MDHS 68 however benzene is used instead of cyclohexane during sample extraction. The Occupational Safety and Health Administration have the permissible exposure limit of 0.2 mg/m3 for coal tar pitch volatiles – benzene soluble fraction to use when assessing worker exposure. This limit was used during this study for assessing tripper car exposure to coal tar pitch volatiles. No coal tar pitch volatiles were detected on the samples collected during the study. The results revealed concentrations below detection limit of the test laboratory analytical method. The detection limit used thereof was 0.1 mg per sample. The tripper car operators were therefore exposed to coal tar pitch volatiles at concentrations that complied with the permissible exposure limit 0.2 mg/m3. The hypothesis of this study was that the tripper car operators at Coal Distribution Steam Plant are over exposed to coal tar pitch volatiles – benzene soluble fraction. This hypothesis is therefore rejected. Based on the results derived from this study it is recommended that further research studies be conducted specifically with focus on different methods of exposure assessment to workers exposed to coal tar pitch volatiles in South African Petrochemical Refinery Plants. - ii - Since the method used was limited to the particulate phase of the contaminant exposure, with the gaseous phase of exposure to coal tar pitch volatiles only looked at when the PEL is exceeded. A method that can measure both the gaseous and particulate phase of the contaminant must be investigated.
24

Avaliação dos níveis de exposição ocupacional ao mercúrio nos consultórios públicos de Araguaína,TO / Evaluation of the levels of occupational exposure to mercury in the public dental offices in Araguaina, TO, Brazil

Xavier, Fernanda Villibor 17 May 2011 (has links)
O objetivo deste trabalho foi realizar a avaliação dos riscos ocupacionais ao mercúrio utilizado em odontologia, aos quais os auxiliares em saúde bucal (ASB) da rede pública de saúde do município de Araguaína, Tocantins, estão expostos. O processo odontológico do sistema de saúde no município em questão foi estudado, de modo minucioso, a partir de um levantamento do número de restaurações de amálgama de prata executadas durante o período de janeiro de 2003 a dezembro de 2007 na base de dados DATASUS. Nesse estudo, foram avaliadas as condições de armazenamento dos resíduos de amálgama nos consultórios odontológicos públicos do município analisado. Foram estudadas diferentes soluções-barreira para armazenamento dos resíduos de amálgama no que diz respeito a sua eficácia no combate à emissão de vapores de mercúrio para o ambiente. A solução contendo amoníaco foi a que apresentou melhor tempo para estocagem dos resíduos (19 dias a 37 ºC), seguida pela solução contendo fixador fotográfico (12 dias) e solução de bicarbonato de sódio (7 dias). Com base nestas informações, caracterizou-se o perfil do ASB que atua nos consultórios públicos do município de Araguaína quanto à idade, ao sexo, ao grau de exposição ao mercúrio e aos procedimentos de biossegurança executados. O estudo possibilitou elaborar um banco de dados, com relação ao manuseio e ao descarte de resíduos de amálgama, com o intuito de subsidiar políticas públicas de saúde voltadas à modificação de situações de risco as quais os profissionais estão submetidos e/ou submetem seus pacientes. Foi realizado também um programa de monitoramento biológico, utilizando como marcador a presença de mercúrio em amostras de urina (HgU), em membros da equipe odontológica da rede municipal de saúde de Araguaína e em alunos da escola técnica de saúde, polo de Araguaína, atuantes como ASB em outros municípios da região norte (n=91). Como comparação, um grupo de não expostos ao mercúrio foi avaliado (n=43) e os valores de HgU determinados. A pesquisa permitiu concluir que, em relação aos valores de HgU, a equipe odontológica avaliada estava dentro dos limites propostos pela NR 7 (até 35 gHg.g-1CR). Com relação à contaminação por mercúrio, a média da concentração do HgU para o grupo expostos (5,61 μgHg.g-1CR) foi aproximadamente 8 vezes maior se comparada ao do grupo não expostos (0,65 μgHg.g-1CR), evidenciando a necessidade de um programa de treinamento de profissionais e de gerenciamento de resíduos, bem como de uma atuação mais efetiva na realização do monitoramento biológico periódico nos profissionais da equipe odontológica. / The aim of this work was to evaluate the occupational risks of exposure to mercury utilized in dentistry, to which dental auxiliaries from the public health system of the city of Araguaína, Tocantins, Brazil are exposed. The dentistry process from the city health system was rigorously studied based on an assessment, in the DATASUS database, of the number of amalgam restorations conducted in the period from January 2003 to December 2009. In this study, we evaluated the storage conditions of mercury residuals in the public dental offices in the studied municipality. Different barrier solutions for the storage of mercury residuals were studied regarding their efficacy in controlling the emission of mercury vapor in the environment. The solution containing ammonia presented the best time of storage of residuals (19 days at 37 °C), followed by the so lution containing photographic fixative (12 days) and the sodium bicarbonate solution (7 days). Based on these information, a profile of the dental auxiliaries actuating in the public dental offices of the city of Araguaína was characterized according to age, sex, level of exposure to mercury and conducted biosecurity procedures. The study allowed the elaboration of a database regarding handling and discard of amalgam residuals, with the purpose to assist public health policies to modify risk situations to which the professionals and/or their patients are exposed. A biological monitoring program was also carried out using as marker the presence of mercury in urine samples (HgU) from members of the dentistry team of the Araguaína public health system and from students from the Araguaína unit of the health care technical school who actuated as dental auxiliaries in other municipalities of the north region of the state (n=91). For comparison, a group of not exposed to mercury was evaluated (n=43), determining their HgU values. The research allowed to conclude that the HgU values from the dentistry team were within the limits set by Regulatory Norm nº 7 by the Brazilian Ministry of Labor (up to 35 gHg.g-1CR). Regarding mercury contamination, the average HgU concentration for the exposed group (5,61 μgHg.g-1CR) was approximately 8 times higher when compared to the values from the not exposed group (0,65 μgHg.g-1CR), making evident the need for a professional training and residuals management program, as well as for a more effective actuation in the realization of periodical biological monitoring in the professionals from the dentistry team.
25

Famílias inseridas no arranjo produtivo informal da produção de joias e bijuterias de Limeira, SP: a exposição ocupacional a contaminantes químicos em ambiente domiciliar / Families inserted in local productive arrangement of the productive chain of jewelry and fashion jewelry from Limeira, SP: the occupational exposure to chemical contaminants in a home setting

Ferreira, Ana Paula Sacone da Silva 22 August 2018 (has links)
Introdução: A informalidade no mercado de trabalho assola muitas economias em desenvolvimento e é uma característica notável da produção de joias e bijuterias em Limeira, São Paulo, um dos maiores polos de produção de joias e bijuterias do Brasil. A produção de joias e bijuterias envolve o manuseio de produtos que podem ter em sua composição elementos com potencial tóxico à saúde humana. Em Limeira, a atividade de produção ocorre dentro dos domicílios, o que significa que o trabalhador e seus familiares podem estar expostos a elementos potencialmente tóxicos (EPT) oriundos da atividade ocupacional. Objetivos: Este estudo investigou a exposição ocupacional aos EPTs Cromo (Cr), Manganês (Mn), Níquel (Ni), Cobre (Cu), Zinco (Zn), Arsênio (As) Cádmio (Cd), Antimônio (Sb), Estanho (Sn), Mercúrio (Hg) e Chumbo (Pb), dos trabalhadores domiciliares e de seus familiares inseridos no arranjo produtivo de joias e bijuterias na cidade de Limeira - SP e discutiu os riscos identificados no ambiente de trabalho domiciliar versus a legislação ocupacional vigente. Métodos: Este estudo incluiu 52 famílias (n=165 indivíduos), divididas em grupo Exposto (n=112) e grupo Controle (n=53). Foram coletadas amostras de sangue (n=165) dos trabalhadores e seus familiares, e amostras de ar da zona de respiração de soldadores (n=9). As concentrações de EPTs foram determinadas por espectrometria de massas com plasma indutivamente acoplado (ICP-MS). Questionários foram aplicados para obter informações sociodemográficas, detalhes das condições do local de trabalho e dos materiais utilizados. As informações relevantes para compor a avaliação do ambiente de trabalho frente aos requisitos legais vigentes foram obtidas a partir destes questionários. Além disso, a análise de componentes principais (PCA), formação de clusters e regressão logística foram realizadas. Resultados: Os elementos Cd, Ni e Cu apresentaram concentração no ar maiores do que as diretrizes ocupacionais americanas. Foi encontrada diferença estatisticamente significativa para a concentração de Pb entre os grupos Exposto e Controle e entre os sexos (p <0,05), já para o Cu e Sb foram encontradas diferenças apenas entre os sexos (p <0,05). Conclusões: As concentrações de EPTs encontradas no ar são preocupantes, uma vez que os familiares dos trabalhadores, incluindo as crianças, estão no mesmo cenário de exposição. Condições inadequadas de trabalho foram observadas nas residências, revelando a necessidade de implementar ações públicas urgentes para proteger essas famílias de trabalhadores. A avaliação do cenário de exposição revelou que os trabalhadores e familiares estão sob os mesmos riscos de exposição, uma vez que a produção de joias é realizada sem nenhuma proteção do trabalhador e em ambiente geralmente compartilhado dentro das casas. Ações públicas e remodelagem do fluxo produtivo são necessárias para proteção social e de saúde destes trabalhadores e seus familiares com foco em melhoria das condições de trabalho e regularização profissional. / Introduction: Informality in the occupational segment devastated many developing economies and is a notable feature of the production of jewelry and fashion jewelry in Limeira city, São Paulo, one of the largest poles of jewelry and fashion jewelry production in Brazil. The production of jewelry and fashion jewelry involves the manipulation of chemical products that may have in their composition potentially toxic elements (PTE) to human health. In Limeira, the production activity occurs inside the households, which means that worker and family members could be exposed to PTE from the occupational activity. Objective: This study investigated occupational exposure to PTE Chromium (Cr), Manganese (Mn), Nickel (Ni), Copper (Cu), and Zinc (Zn), Arsenic (As), Cadmium (Cd), Antimony (Sb), Tin (Sn), Mercury (Hg), and Lead (Pb), household workers and their families included in the production of jewelry and fashion jewelry in Limeira, and discussed the risks identified in the households\' occupational environment assessment versus the current occupational legislation. Methods: This study included 52 families (n = 165 individuals), divided into Exposed group (n = 112) and Control group (n = 53). Blood samples (n = 165) were collected from the workers and their relatives, and air samples from the breathing zone of welders (n = 9). Concentrations of EPTs were determined by ICP-MS. Questionnaires were applied to collect sociodemographic information, details of the workplace conditions and the materials used. The relevant information to compose the occupational environment assessment against the current legal requirements were obtained from these questionnaires. In addition, the principal component analysis (PCA), clusters formation and logistic regression were performed. Results: Cd, Ni, and Cu elements presented higher air concentration than the American occupational guidelines limits. A statistically significant difference was found for the Pb concentration between the exposed and control groups and between the sexes (p <0.05), whereas for Cu and Sb only differences between the sexes were found (p <0.05). Conclusions: Concentrations of EPT found in the air raise concern, since workers\' relatives, including children, are in the same exposure scenario. Inadequate working conditions were observed in the houses, revealing the need to implement urgent public actions to protect these families and the workers. The exposure assessment revealed that workers and family members are at the same risk of exposure as the production of jewelry is carried out without any individual protection and, generally, is performed in the shared environment inside the houses. Public actions and remodeling the productive flow are necessary for the social and health protection of these workers and the families with a focus on improving working conditions and professional regularization.
26

Avaliação dos níveis de exposição ocupacional ao mercúrio nos consultórios públicos de Araguaína,TO / Evaluation of the levels of occupational exposure to mercury in the public dental offices in Araguaina, TO, Brazil

Fernanda Villibor Xavier 17 May 2011 (has links)
O objetivo deste trabalho foi realizar a avaliação dos riscos ocupacionais ao mercúrio utilizado em odontologia, aos quais os auxiliares em saúde bucal (ASB) da rede pública de saúde do município de Araguaína, Tocantins, estão expostos. O processo odontológico do sistema de saúde no município em questão foi estudado, de modo minucioso, a partir de um levantamento do número de restaurações de amálgama de prata executadas durante o período de janeiro de 2003 a dezembro de 2007 na base de dados DATASUS. Nesse estudo, foram avaliadas as condições de armazenamento dos resíduos de amálgama nos consultórios odontológicos públicos do município analisado. Foram estudadas diferentes soluções-barreira para armazenamento dos resíduos de amálgama no que diz respeito a sua eficácia no combate à emissão de vapores de mercúrio para o ambiente. A solução contendo amoníaco foi a que apresentou melhor tempo para estocagem dos resíduos (19 dias a 37 ºC), seguida pela solução contendo fixador fotográfico (12 dias) e solução de bicarbonato de sódio (7 dias). Com base nestas informações, caracterizou-se o perfil do ASB que atua nos consultórios públicos do município de Araguaína quanto à idade, ao sexo, ao grau de exposição ao mercúrio e aos procedimentos de biossegurança executados. O estudo possibilitou elaborar um banco de dados, com relação ao manuseio e ao descarte de resíduos de amálgama, com o intuito de subsidiar políticas públicas de saúde voltadas à modificação de situações de risco as quais os profissionais estão submetidos e/ou submetem seus pacientes. Foi realizado também um programa de monitoramento biológico, utilizando como marcador a presença de mercúrio em amostras de urina (HgU), em membros da equipe odontológica da rede municipal de saúde de Araguaína e em alunos da escola técnica de saúde, polo de Araguaína, atuantes como ASB em outros municípios da região norte (n=91). Como comparação, um grupo de não expostos ao mercúrio foi avaliado (n=43) e os valores de HgU determinados. A pesquisa permitiu concluir que, em relação aos valores de HgU, a equipe odontológica avaliada estava dentro dos limites propostos pela NR 7 (até 35 gHg.g-1CR). Com relação à contaminação por mercúrio, a média da concentração do HgU para o grupo expostos (5,61 &mu;gHg.g-1CR) foi aproximadamente 8 vezes maior se comparada ao do grupo não expostos (0,65 &mu;gHg.g-1CR), evidenciando a necessidade de um programa de treinamento de profissionais e de gerenciamento de resíduos, bem como de uma atuação mais efetiva na realização do monitoramento biológico periódico nos profissionais da equipe odontológica. / The aim of this work was to evaluate the occupational risks of exposure to mercury utilized in dentistry, to which dental auxiliaries from the public health system of the city of Araguaína, Tocantins, Brazil are exposed. The dentistry process from the city health system was rigorously studied based on an assessment, in the DATASUS database, of the number of amalgam restorations conducted in the period from January 2003 to December 2009. In this study, we evaluated the storage conditions of mercury residuals in the public dental offices in the studied municipality. Different barrier solutions for the storage of mercury residuals were studied regarding their efficacy in controlling the emission of mercury vapor in the environment. The solution containing ammonia presented the best time of storage of residuals (19 days at 37 °C), followed by the so lution containing photographic fixative (12 days) and the sodium bicarbonate solution (7 days). Based on these information, a profile of the dental auxiliaries actuating in the public dental offices of the city of Araguaína was characterized according to age, sex, level of exposure to mercury and conducted biosecurity procedures. The study allowed the elaboration of a database regarding handling and discard of amalgam residuals, with the purpose to assist public health policies to modify risk situations to which the professionals and/or their patients are exposed. A biological monitoring program was also carried out using as marker the presence of mercury in urine samples (HgU) from members of the dentistry team of the Araguaína public health system and from students from the Araguaína unit of the health care technical school who actuated as dental auxiliaries in other municipalities of the north region of the state (n=91). For comparison, a group of not exposed to mercury was evaluated (n=43), determining their HgU values. The research allowed to conclude that the HgU values from the dentistry team were within the limits set by Regulatory Norm nº 7 by the Brazilian Ministry of Labor (up to 35 gHg.g-1CR). Regarding mercury contamination, the average HgU concentration for the exposed group (5,61 &mu;gHg.g-1CR) was approximately 8 times higher when compared to the values from the not exposed group (0,65 &mu;gHg.g-1CR), making evident the need for a professional training and residuals management program, as well as for a more effective actuation in the realization of periodical biological monitoring in the professionals from the dentistry team.
27

Occupational exposure to ethylene oxide in women sterilising staff working in Gauteng province, South Africa: Exposure assessment and association with adverse reproductive outcome

Gresie-Brusin, Florentina Daniela 10 November 2006 (has links)
Faculty of health sciences School of Public Health 0204521g dgresie@yahoo.co.uk;dgresie@hotmail.com / Ethylene oxide is used widely in hospitals as a gaseous sterilant for heat-sensitive medical items, surgical instruments and other objects and fluids that come into contact with biological tissues. Although ethylene oxide is recognised as a reproductive toxicant in humans, so far few studies have been carried out to investigate the association between exposure to ethylene oxide and the occurrence of adverse reproductive outcomes (Hemminki et al 1982 and 1983; Rowland et al, 1996; Yakubova et al, 1976). The results of these studies suggested that ethylene oxide is capable of causing reproductive dysfunction and that further research is needed in order to understand its effects on reproductive health. This study investigated the association between exposure to ethylene oxide during pregnancy and adverse reproductive outcome in women sterilising staff working in sterilising units using ethylene oxide in Gauteng province, South Africa. The study had the following objectives: 1) to describe the extent and nature of ethylene oxide use in sterilising units operational in medical facilities in Gauteng; 2) to assess the current exposure to ethylene oxide in sterilising units in Gauteng; 3) to collect information on the last recognised pregnancy using a questionnaire; 4) to assess the validity of the information on the evolution and outcome of the last recognised pregnancy collected by the means of the questionnaire; 5) to assess the association between occupational exposure to ethylene oxide during pregnancy and adverse reproductive outcome. The study population was represented by singleton pregnancies that: 1) occurred in women currently working in sterilising units using ethylene oxide in Gauteng province, South Africa; 2) were the last recognised pregnancy occurring in these women after the 1st January 1992; 3) occurred while the mother was employed. The adverse reproductive outcome was defined as the occurrence of any the following: spontaneous abortion, still birth, pregnancy loss (spontaneous abortion or still birth), low birth weight and combined adverse reproductive outcome (spontaneous abortion, still birth or low birth weight). The study enrolled 68.8% of the medical facilities in Gauteng that were using ethylene oxide to sterilise medical equipment. The majority of the employees working in the sterilising units included in the study were women (96.6%) and they were employed in one of the following jobs: technician (operator), instrument packer and cleaner. xiii Most of the sterilising units participating in the study used ethylene oxide sterilisation daily and only 15.4% of them reported that the employees operating the ethylene oxide steriliser used protective clothing. Recorded levels of ethylene oxide were provided by 46.2% of the sterilising units; they were all bellow 0.25 ppm (the South African long-term exposure limit for occupational exposure to ethylene oxide is 5 ppm). Changes in ethylene oxide sterilisation equipment and or technology were reported by 42.3% of the sterilising units and they were all engineering control measures aimed at reducing exposure to ethylene oxide. Measurements of the current levels of ethylene oxide were performed at the time of the study by the National Institute for Occupational Health using hydrobromic acid-coated petroleum charcoal tubes connected to calibrated Gilian pumps through which air containing ethylene oxide was drawn. The samples were analysed by the Analytical Services of the National Institute for Occupational Health. A total of 418 samples were collected (100 blank samples, 97 personal samples and 221 static samples). Quality control was ensured by the following methods: 1) verification by an Approved Inspection Authority; 2) collection of duplicate samples; 3) collection of blank samples. These measurements showed that exposure to ethylene oxide still occurred in sterilising units (ethylene oxide was detected in 9 out of the 10 public hospitals) and that the employees most exposed are the ones working with the ethylene oxide steriliser (technician or operator). There were 113 women working in the sterilising units enrolled in the study who had been pregnant after the 1st January 1992; 109 of them agreed to participate in the study and to complete the questionnaire. Information on exposure to ethylene oxide during pregnancy was obtained from three sources: walk-through survey, questionnaire-collected data and measurements of the levels of ethylene oxide in sterilising units at the time of the study. Information on the evolution and outcome of these pregnancies was gathered from the mother using a questionnaire. The questionnaire collected demographic data, reproductive history, medical data, risk factors for the adverse reproductive outcome (environmental and occupational exposures, lifestyle), and data regarding the evolution and outcome of the last recognised pregnancy. The questionnaire also collected detailed information on the job held at the time of the last recognised pregnancy (if the woman was working with ethylene oxide, she was asked to provide a complete list of daily tasks she was performing). Prior to administration, the questionnaire was tested on a small sample of working women. xiv The validity of the questionnaire-collected information on the evolution and outcome of the last recognised pregnancy was assessed by comparing this information against medical records (considered the “gold standard”). The assessment showed that mothers’ recall was accurate for the following variables: medical facility were the pregnancy was recorded, date of the reproductive event, gestation length, vital status of the newborn, number of foetuses, child gender, disease/medical problems during pregnancy and treatment received during pregnancy. There was an error in the mothers’ reporting of the birth weight of their babies. The possible misclassification of outcome resulting from this error was shown to be nondifferential (the proportion of subjects misclassified on outcome did not depend on exposure). Therefore, this misclassification could bias the effect estimate towards the null value or it could not produce any bias at all. The analysis carried out to detect possible associations between exposure to ethylene oxide and adverse reproductive outcomes included 98 of the initial 109 pregnancies on which information had been collected (11 pregnancies were excluded from the analysis for the following reasons: 2 were multiple pregnancies, 4 were conceived before 1st January 1992 and 5 were conceived while the mother was not employed). Amongst the 98 singleton pregnancies included in the analysis, 19 were classified as exposed and 79 as unexposed to ethylene oxide. The relative risk for spontaneous abortion was RR=16.63 (95%CI=1.97-140.42; p=0.004), for stillbirths RR=3.47 (95%CI=0.63-19.01; p=0.18), for pregnancy loss RR=6.24 (95%CI=1.95- 19.93; p=0.003), for low birth weight RR=0.61 (95%CI=0.09-4.30; p=0.51) and for combined adverse reproductive outcome RR=2.09 (95%CI=1.00-4.36; p=0.06). No confounders were detected for any of the associations between exposure to ethylene oxide and the adverse reproductive outcomes under study. For the association between exposure to ethylene oxide and combined adverse reproductive outcome the analysis detected three effect modifiers: paternal age (father aged 40 or older at conception), passive smoking and maternal age (mother aged 35 or older at conception). In conclusion, this study, the first in South Africa on ethylene oxide exposure and adverse reproductive outcomes, confirmed the widespread use of ethylene oxide, exposure to this agent in public sector hospitals and associations between exposure to ethylene oxide and spontaneous abortion and between exposure to ethylene oxide and pregnancy loss (either spontaneous abortion or stillbirth). xv Moreover, the study provided data on reproductive outcomes in employed women (on which scant data are available in South Africa) and added information on the validity of selfreported pregnancy data relative to medical records. The findings of the study support the conclusions of the previous studies that had suggested that exposure to ethylene oxide during pregnancy could lead to adverse reproductive outcomes. The study detected no associations between exposure to ethylene oxide and stillbirth, low birth weight or between exposure to ethylene oxide and combined adverse reproductive outcome.
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Utilizing urinary biomarkers in Egyptian adolescent applicators and non-applicators to characterize pesticide exposure to λ-cyhalothrin, α-cypermethrin, chlorpyrifos and profenofos applied on cotton crops over time

Okeke, Barbara C. 01 May 2018 (has links)
Organophosphates (OPs) and Pyrethroids (PYRs) are widely used pesticides in both agricultural and non-agricultural environments. In agricultural work settings, typically more than one pesticide is used in combination, or sequentially, to kill pests. There is currently a gap in research that looks at how exposures to multiple pesticides can impact human health – particularly among adolescents who work in these environments. The goal of this dissertation research was to examine the use of OP (chlorpyrifos, and profenofos) and PYR (λ-Cyhalothrin, α-Cypermethrin) pesticides across an application season and how exposure is associated with symptoms and cholinesterase enzyme activity, and to examine the impact of a sequential exposure to multiple OPs, and exposure to both OPs and PYRs. Urine and blood samples, questionnaire data, and a medical exam were collected over a 10-month period from adolescent pesticide applicators in Egypt. Overall, applicators had higher exposure than non-applicators to all four pesticides. The non-applicators were also exposed and had levels 4 times higher in urine metabolite levels than the general population in the U.S. In addition, these exposures caused increased symptoms and severity of symptoms among both applicators and non-applicators. In conclusion, adolescent agriculture workers in the Egyptian cotton fields are exposed to multiple pesticides and are susceptible to the impact of those exposures on their health.
29

Exposure to airborne asbestos in Jamaican hospitals

Scarlett, Henroy P. January 2007 (has links) (PDF)
Thesis (D.P.H.)--University of Alabama at Birmingham, 2007. / Title from PDF title page (viewed on Feb. 19, 2010). Includes bibliographical references (p. 145-153).
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Estimating the burden of occupational bladder cancer in Ontario using the CAREX Canada database

Angeles, Joy 04 September 2008 (has links)
Objective: This study attempts to estimate the proportion of incident cases of bladder cancer in Ontario, Canada that is due to exposure to occupational carcinogens. Methods: The population attributable risk approach is used to estimate the proportion of bladder cancer in Ontario that is due to occupation. Risk ratios were obtained from a review of epidemiologic literature using a priori inclusion and exclusion criteria. Summary risk estimates for each bladder carcinogen included were calculated using RevMan 4.2. The CAREX Canada database provided Ontario-specific estimates of the proportion of workers exposed to bladder carcinogens. Results: In Ontario, the proportion of bladder cancer due to occupational exposure is approximately 5.6% (95% CI 0.2% to 14%). Based on the incident number of bladder cancer cases in 2001 in Ontario, it is estimated that approximately 52 new cases of bladder cancer were due to occupational exposure to polycyclic aromatic hydrocarbons (PAHs), diesel exhaust, aromatic amines and 2-naphthylamine. An alternate interpretation is if these occupational exposures were eliminated, 52 cases of bladder cancer per year in Ontario alone could be avoided. Conclusion and Recommendations: The current study advances our knowledge of the extent to which specific occupational bladder carcinogens contribute to the overall bladder cancer burden in Ontario. The current study highlights the utility of the CAREX Canada database in advancing current knowledge on the burden of occupational cancer in Ontario. The methods used to estimate the proportion of bladder cancer attributable to occupational exposure in Ontario may be replicated to estimate the proportion of cancer in Ontario that is due to occupational exposure. / Thesis (Master, Community Health & Epidemiology) -- Queen's University, 2008-08-29 20:08:46.713

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